Workability Limits of Magnesium Alloy AZ31B Subjected to Equal Channel Angular Pressing
NASA Astrophysics Data System (ADS)
Arun, M. S.; Chakkingal, Uday
2018-03-01
Equal channel angular pressing (ECAP) is an important severe plastic deformation process to produce ultrafine grained microstructures in metals and alloys. Magnesium and its alloys generally possess poor workability at temperatures below 250 °C. This investigation examines the influence of different passes and processing routes of ECAP on improving the workability of Mg alloy AZ31B. ECAP was carried out for three passes using a die of angle 120° using processing routes Bc and C. The operating temperature was 523 K for the first pass and 423 K for the subsequent two passes. The resultant microstructure and mechanical properties were determined. Workability of the alloy at 423 K (150 °C) was determined using upsetting experiments on cylindrical specimens machined from the annealed and ECAPed samples. Workability limit diagrams have been constructed for the various processed conditions. The workability data generated were also analyzed using five different workability criteria (also referred to as ductile fracture models) and the material constants for these five models were evaluated. Specimens processed by two passes through route C (pass 2C) exhibits better workability compared to other passes since the workability limit line after this pass shows maximum safe working area and lies above the other workability lines. Among the five different workability criteria investigated, the Freudenthal workability criterion is more suitable for prediction of failure in this alloy.
Kustas, Andrew B.; Johnson, David R.; Trumble, Kevin P.; ...
2018-07-01
Enhanced workability, as characterized by the magnitude and heterogeneity of accommodated plastic strains during sheet processing, is demonstrated in high Si content Fe-Si alloys containing 4 and 6.5 wt% Si using two single-step, simple-shear deformation techniques – peeling and large strain extrusion machining (LSEM). The model Fe-Si material system was selected for its intrinsically poor material workability, and well-known applications potential in next-generation electric machines. In a comparative study of the deformation characteristics of the shear processes with conventional rolling, two distinct manifestations of workability are observed. For rolling, the relatively diffuse and unconfined deformation zone geometry leads to crackingmore » at low strains, with sheet structures characterized by extensive deformation twinning and banding. Workpiece pre-heating is required to improve the workability in rolling. In contrast, peeling and LSEM produce continuous sheet at large plastic strains without cracking, the result of more confined deformation geometries that enhances the workability. Peeling, however, results in heterogeneous, shear-banded microstructures, pointing to a second type of workability issue – flow localization – that limits sheet processing. This shear banding is to a large extent facilitated by unrestricted flow at the sheet surface, unavoidable in peeling. With additional confinement of this free surface deformation and appropriately designed deformation zone geometry, LSEM is shown to suppress shear banding, resulting in continuous sheet with homogeneous microstructure. Thus LSEM is shown to produce the greatest enhancement in process workability for producing sheet. In conclusion, these workability findings are explained and discussed based on differences in process mechanics and deformation zone geometry.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kustas, Andrew B.; Johnson, David R.; Trumble, Kevin P.
Enhanced workability, as characterized by the magnitude and heterogeneity of accommodated plastic strains during sheet processing, is demonstrated in high Si content Fe-Si alloys containing 4 and 6.5 wt% Si using two single-step, simple-shear deformation techniques – peeling and large strain extrusion machining (LSEM). The model Fe-Si material system was selected for its intrinsically poor material workability, and well-known applications potential in next-generation electric machines. In a comparative study of the deformation characteristics of the shear processes with conventional rolling, two distinct manifestations of workability are observed. For rolling, the relatively diffuse and unconfined deformation zone geometry leads to crackingmore » at low strains, with sheet structures characterized by extensive deformation twinning and banding. Workpiece pre-heating is required to improve the workability in rolling. In contrast, peeling and LSEM produce continuous sheet at large plastic strains without cracking, the result of more confined deformation geometries that enhances the workability. Peeling, however, results in heterogeneous, shear-banded microstructures, pointing to a second type of workability issue – flow localization – that limits sheet processing. This shear banding is to a large extent facilitated by unrestricted flow at the sheet surface, unavoidable in peeling. With additional confinement of this free surface deformation and appropriately designed deformation zone geometry, LSEM is shown to suppress shear banding, resulting in continuous sheet with homogeneous microstructure. Thus LSEM is shown to produce the greatest enhancement in process workability for producing sheet. In conclusion, these workability findings are explained and discussed based on differences in process mechanics and deformation zone geometry.« less
ERIC Educational Resources Information Center
Van Patten, Betsy
1984-01-01
Grant proposals are most likely to succeed when they are based on solid, well-conceived ideas. Long-range planning is the best way to come up with workable ideas that will convince small foundations of a project's merits. Planning helps identify an institution's top priorities and achieve a consensus. (MLW)
Influence of Cellulosic Fibres on the Physical Properties of Fibre Cement Composites
NASA Astrophysics Data System (ADS)
Hospodarova, V.; Stevulova, N.; Vaclavik, V.; Dvorsky, T.
2017-10-01
Nowadays, there are new approaches directing to processing of non-conventional fibre-cement composites for application in the housing construction. Vegetable cellulosic fibres coming from natural resources used as reinforcement in cost-effective and environmental friendly building products are in the spotlight. The applying of natural fibres in cement based composites is narrowly linked to the ecological building sector, where a choice of materials is based on components including recyclable, renewable raw materials and low-resource manufacture techniques. In this paper, two types of cellulosic fibres coming from wood pulp and recycled waste paper with 0.2%; 0.3% and 0.5% of fibre addition into cement mixtures were used. Differences in the physical characteristics (flowability, density, coefficient of thermal conductivity and water absorbability) of 28 days hardened fibre-cement composites are investigated. Addition of cellulosic fibres to cement mixture caused worsening the workability of fresh mixture as well as absorbability of hardened composites due to hydrophilic nature of biomaterial, whereas density and thermal conductivity of manufactured cement based fibre plaster are enhanced. The physical properties of cement plasters based on cellulosic fibres depend on structural, physical characteristics of cellulosic fibres, their nature and processing.
A Comparison of Increment Core Sampling for Estimating Tree Specific Gravity
Michael A. Taras; Harold E. Wadlgren
1963-01-01
Increment cores have been used to evaluate such tree characteristics as age, rate of growth, percentage of various types of tissue, chemical composition, and density. Of the wood characteristics listed, density has come to be of considerable interest to numerous researchers, since it is highly correlated with the strength properties, workability, and weight of wood....
Effects of TEA·HCl hardening accelerator on the workability of cement-based materials
NASA Astrophysics Data System (ADS)
Pan, Wenhao; Ding, Zhaoyang; Chen, Yanwen
2017-03-01
The aim of the test is to research the influence rules of TEA·HCl on the workability of cement paste and concrete. Based on the features of the new hardening accelerator, an experimental analysis system were established through different dosages of hardening accelerator, and the feasibility of such accelerator to satisfy the need of practical engineering was verified. The results show that adding of the hardening accelerator can accelerate the cement hydration, and what’s more, when the dosage was 0.04%, the setting time was the shortest while the initial setting time and final setting time were 130 min and 180 min, respectively. The initial fluidity of cement paste of adding accelerator was roughly equivalent compared with that of blank. After 30 min, fluidity loss would decrease with the dosage increasing, but fluidity may increase. The application of the hardening accelerator can make the early workability of concrete enhance, especially the slump loss of 30 min can improve more significantly. The bleeding rate of concrete significantly decreases after adding TEA·HCl. The conclusion is that the new hardening accelerator can meet the need of the workability of cement-based materials in the optimum dosage range.
Cold-workability limits for carbon and alloy steels
NASA Astrophysics Data System (ADS)
El-Domiaty, A.
1999-04-01
In metalforming, the success in accomplishing the required deformation without failure of the forming tools or cracking of the work material represents the major concern for manufacture and design engineers. The degree of deformation that can be achieved in a particular metalworking process without creating an undesirable condition is defined as workability. In the present work, an experimental investigation was carried out to determine the cold-workability limits for five different types of steel: AISI 1018, 1045, 1078, 4140, and 4340. The upset (compression) test was used to determine the workability limit for each type. The upset dies and specimen geometries were designed to give different strain paths covering the range from homogeneous deformation (ɛz/ɛθ=-2.0) to close to plane-strain condition (ɛz/ɛθ=0.0). Grid pattern was printed on the specimen surface in order to measure the axial and hoop strain components during deformation. Specific elements were selected on the specimen surface, and their strain paths were determined. Each strain path was terminated once surface cracking had been observed. The ends of the strain paths, at which macrocracks were observed, were connected to obtain the workability limit on the forming-limit diagram. The workability limit of AISI 1018 is the highest among the other types of steel.
Hazardous Material Transportation Risks in the Puget Sound Region
DOT National Transportation Integrated Search
1981-09-01
In order to contribute to workable hazardous materials accident prevention and response systems, public safety risks of transporting hazardous materials in the Central Puget Sound Region of Washington State are determined. Risk spectrums are obtained...
NASA Astrophysics Data System (ADS)
Lima, Nathan B.; Rogerio, V. A.; Belarmino, Marcia K. D. L.; Silva, Anderson I. S.; Ioras, Renan U. F.; Oliveira, Romilde A.; Lima, Nathalia B. D.
2018-07-01
A chemical rationalization of the processing and application of the roughcast and plaster mortar coatings was advanced. The results revealed that the structural and thermodynamic nature of the hydrogen-bonded complexes between the inorganic precursors and water molecules are associated with the physical properties of both coatings. In this sense, the workability and curing time of the roughcast and the plaster mortars studied, seemingly, are related to the nature of the water solvation in the main components of these materials: calcium hydroxide and silicon dioxide. In addition, PM7 and PM7/COSMO results indicate that the enthalpy of solvation of water by hydrogen bonds in calcium hydroxide is stronger when compared with silicon dioxide systems. Therefore, the presence of free hydrated lime (calcium hydroxide) in the precursor mixture of plaster mortar leads to the large workability and elapsed curing time of this material. On the other hand, the absence of free hydrated lime in the precursor mixture of the roughcast mortar leads to its poor workability and faster elapsed curing time. Further, fluorescence microscopy experiments revealed that the inorganic compounds present in the cement precursor were transformed into different materials, that exhibit red and blue fluorescence. Finally, mechanical tests showed a tensile strength average 0.67 MPa for the plaster mortar material, whereas for the roughcast material is 0.53 MPa.
Long, Wu-Jian; Khayat, Kamal Henri; Lemieux, Guillaume; Hwang, Soo-Duck; Han, Ning-Xu
2014-03-27
Adequate selection of material constituents and test methods are necessary for workability specifications and performance of hardened concrete. An experimental program was performed to evaluate the suitability of various test methods for workability assessment and to propose performance specifications of prestressed concrete. In total, 33 self-consolidating concrete (SCC) mixtures made with various mixture proportioning parameters, including maximum size and type of aggregate, type and content of binder, and w/cm were evaluated. Correlations among various test results used in evaluating the workability responses are established. It is recommended that SCC should have slump flow values of 635-760 mm. To ensure proper filling capacity greater than 80%, such concrete should have a passing ability that corresponds to L-box blocking ratio (h₂/h₁) ≥ 0.5, J-Ring flow of 570-685 mm, slump flow minus J-Ring flow diameter ≤75 mm. Moreover, Stable SCC should develop a column segregation index lower than 5%, and rate of settlement at 30 min of 0.27%/h for SCC proportioned with 12.5 or 9.5 mm MSA. It is recommended that SCC should have a plastic viscosity of 100-225 Pa·s and 100-400 Pa·s for concrete made with crushed aggregate and gravel, respectively, to ensure proper workability.
Effects of using blended binder of RHA and GGBS on the properties of concrete: A review
NASA Astrophysics Data System (ADS)
Ishak, Nuril Izzeaty; Johari, Megat Azmi Megat; Hashim, Syed Fuad Saiyid
2017-10-01
Concern about protecting and preserving the environment has driven many researchers to innovate the concrete materials in pursuing better mechanical and physical properties of the fresh and hardened concrete. This paper presents an overview of the microstructural properties, workability, and strength performance of concrete incorporated with mineral admixtures from rice husk ash (RHA) and ground granulated blast-furnace slag (GGBS). The substitution of these supplementary cementitious materials as a ternary blended binder concrete has also been included. It was found that, the average of RHA replacement in concrete is about 10%, while for GGBS is in the range of 40 to 50 % replacement of Portland cement. The results from previous studies yield to a better strength and could potentially be used as high performance concrete, but the high replacement with RHA decreased workability and required more water demand due to the micro porous character, high specific surface area and higher in carbon content of the material. Thus, the necessity of using superlasticizer is crucial to improve the workability and strength. The collection of comprehensive literatures elaborated that the usage of RHA and GGBS enhanced the properties of concrete while gives a better solution for the plenteous of waste produced from the agricultural and industrial sectors.
Optimization of superplasticizer in portland pozzolana cement mortar and concrete
NASA Astrophysics Data System (ADS)
Sathyan, Dhanya; Anand, K. B.; Mini, K. M.; Aparna, S.
2018-02-01
Chemical Admixtures are added to concrete at the time of mixing of its constituents to impart workability. The requirement of right workability is the essence of good concrete. It has been found that the use of optimum use of admixtures is very important since low dosage may result in loss of fluidity and over dosage could lead to segregation, bleeding, excessive air entrainment etc in concrete. Hence it is essential to find optimum dosage of superplasticizer for getting good strength and workability. But large number of trial tests are required in the field to find the saturation dosage of superplasticizer in concrete which requires more materials and consume more time. The paper deals with developing a co-relation between the quantity requirements of superplasticiser in mortar to that of cement concrete to get good workability. In this work for preparing mortar and concrete 4 brands of locally available Portland pozzolana cement (PPC) and superplasticizer (SP) belonging to 4 different families namely Polycarboxylate Ether (PCE), Lignosulphate (LS), Sulfonated Naphthalene Formaldehyde (SNF) and Sulfonated Melamine Formaldehyde (SMF) are used. Two different brands of SP’s are taken from each family. Workability study on the superplasticized mortar with cement to sand ratio 1:1.5 and water cement ratio of 0.4 was performed using marsh cone and flow table test and workability study on the concrete with same cement/sand ratio and water cement ratio was done using slump cone and flow table test. Saturation dosage of superplasticizer in mortar and concrete determined experimentally was compared to study the correlation between two. Compressive strength study on concrete cubes were done on concrete mixes with a superplasticizer dosage corresponding to the saturation dosage and a comparative study were done to analyse the improvement in the compressive strength with addition of superplasticizer from different family.
NASA Astrophysics Data System (ADS)
Wardhono, Arie; Law, David W.; Sutikno, Dani, Hasan
2017-09-01
This paper presents the effect of slag addition on strength development and workability of fly ash/slag based geopolymer (FASLG) concrete cured at normal temperature. Class C fly ash with high ferrite (Fe) content was used as the primary material. The proportions of fly ash (FA) to slag (SL) are: 1 FA : 0 SL, 0.9 FA : 0.1 SL, 0.7 FA : 0.3 SL, and 0.5 FA : 0.5 SL. The workability and strength properties were determined by slump, vikat, and compressive strength tests. The result shows that the highest compressive strength was achieved by FASLG-3 concrete with 30% slag addition and exhibited a comparable strength to that normal concrete at 28 days. The 30% slag addition also improve the workability and increase the setting time of FASLG concrete specimens. It can be concluded that the slag inclusion on fly ash will improve the performance of geopolymer concrete at normal temperature.
Aerospace Materials Process Modelling
1988-08-01
development of advanced technologies for the fabrication of close-tolerance parts, in conjunction with the development of advanced materials, plays a key...1883. 17. Gegel, H. L., et al., "Materials Modeling and Intrinsic Workability for Simulation of Bulk Deformiti6n," Advanced Technology of Plasticity, Vol...process in the last three decades. As a result of technological advances gained in aerospace industry there has been an increasing demand for the
Applying workability in the Australian residential aged care context.
Brooke, Elizabeth; Goodall, Joanne; Handrus, Maxwell; Mawren, Daveena
2013-06-01
The study is based on an innovative demonstration project which trialled the implementation of the Finnish 'workability' framework and research measures. It aimed, firstly, to test the applicability of the Workability Index (WAI) to the Australian residential aged care workforce, focusing on personal care assistants (PCAs), and secondly, to assess the effectiveness of actions aimed at improving workability. The facility manager implemented multidimensional 'actions' according to the workability framework. The Workability Survey (WAS) and WAI and intervention instruments were administered (n = 64). Completed responses to 'pre' and 'post' instruments formed matched pairs (n = 15). WAI scores increased significantly, by 3 points on average, after all 'actions' were implemented. The only significant 'action' was increasing the number of PCAs in high care. Workability provides a useful research workforce development instrument measuring interactions between aged care workers and organisational demands and the outcomes of 'actions'. © 2013 The Authors. Australasian Journal on Ageing © 2013 ACOTA.
Evaluation of concrete recycling system efficiency for ready-mix concrete plants.
Vieira, Luiz de Brito Prado; Figueiredo, Antonio Domingues de
2016-10-01
The volume of waste generated annually in concrete plants is quite large and has important environmental and economic consequences. The use of fresh concrete recyclers is an interesting way for the reuse of aggregates and water in new concrete production. This paper presents a study carried out for over one year by one of the largest ready-mix concrete producers in Brazil. This study focused on the evaluation of two recyclers with distinct material separation systems, herein referred to as drum-type and rotary sieve-type equipment. They were evaluated through characterization and monitoring test programs to verify the behaviour of recovered materials (aggregates, water, and slurry). The applicability of the recovered materials (water and aggregates) was also evaluated in the laboratory and at an industrial scale. The results obtained with the two types of recyclers used were equivalent and showed no significant differences. The only exception was in terms of workability. The drum-type recycler generated fewer cases that required increased pumping pressure. The analysis concluded that the use of untreated slurry is unfeasible because of its intense negative effects on the strength and workability of concrete. The reclaimed water, pre-treated to ensure that its density is less than 1.03g/cm(3), can be used on an industrial scale without causing any harm to the concrete. The use of recovered aggregates consequently induces an increase in water demand and cement consumption to ensure the workability conditions of concrete that is proportional to the concrete strength level. Therefore, the viability of their use is restricted to concretes with characteristic strengths lower than 25MPa. Copyright © 2016 Elsevier Ltd. All rights reserved.
Standard Specification for Language Laboratory.
ERIC Educational Resources Information Center
North Carolina State Dept. of Administration, Raleigh.
This specification covers the components of electronic and electromechanical equipment, nonelectronic materials for the teacher-student positions, and other items of a miscellaneous nature to provide for a complete and workable language laboratory facility. Language laboratory facilities covered by this specification are of two types: (1)…
Standard Specifications for Language Laboratory.
ERIC Educational Resources Information Center
North Carolina State Dept. of Administration, Raleigh.
Specifications are presented covering the components of electronic and electro-mechanical equipment, non-electrical materials for the teacher-student positions, and other items of a miscellaneous nature to provide for a complete, workable language laboratory facility. Instructions for the use of specifications are included for the purchaser,…
Vocational Preparation Curriculum: Welding.
ERIC Educational Resources Information Center
Usoro, Hogan
Designed to be a workable guide for instructors serving the occupational needs of various categories of disadvantaged and handicapped students, this welding curriculum contains fourteen units of self-paced and self-contained instructional materials. The instructional units cover the following topics: job opportunities in welding, safety rules in…
TECHNIQUES FOR EFFECTIVE TEACHING.
ERIC Educational Resources Information Center
HASTINGS, GERALDINE; AND OTHERS
A COMPENDIUM OF WORKABLE AND REASONABLE TECHNIQUES TO PROVIDE TEACHERS WITH ALTERNATIVES IN SELECTING LEARNING EXPERIENCES IS PRESENTED. MATERIALS ARE DESIGNED TO AID TEACHERS AND LEARNERS IN ALL SUBJECT MATTER AREAS. TEACHING TECHNIQUES DESCRIBED ARE (1) THE CASE STUDY, (2) DISCUSSIONS SUCH AS SYMPOSIUM, COLLOQUIUM, BUZZ SESSIONS, AND…
Cost-Effective Uses of Lightweight Aggregate Made from Dredged Material in Construction
DOT National Transportation Integrated Search
2018-01-31
Lightweight aggregate (LWA) can be used in concrete to reduce its self-weight and improve its workability and durability. It could potentially be used as borrow for embankment construction, which is expected to reduce the stresses on the subgrade fou...
Oxidation behaviour of silicon-free tungsten alloys for use as the first wall material
NASA Astrophysics Data System (ADS)
Koch, F.; Brinkmann, J.; Lindig, S.; Mishra, T. P.; Linsmeier, Ch
2011-12-01
The use of self-passivating tungsten alloys as armour material of the first wall of a fusion power reactor may be advantageous concerning safety issues. In earlier studies good performance of the system W-Cr-Si was demonstrated. Thin films of such alloys showed a strongly reduced oxidation rate compared to pure tungsten. However, the formation of brittle tungsten silicides may be disadvantageous for the powder metallurgical production of bulk W-Cr-Si alloys if a good workability is needed. This paper shows the results of screening tests to identify suitable silicon-free alloys with distinguished self-passivation and a potentially good workability. Of all the tested systems W-Cr-Ti alloys showed the most promising results. The oxidation rate was even lower than the one of W-Cr-Si alloys, the reduction factor was about four orders of magnitude compared to pure tungsten. This performance could be conserved even if the content of alloying elements was reduced.
Portland-cement concrete rheology and workability : final report.
DOT National Transportation Integrated Search
2011-04-01
Methods for determining the workability of freshly mixed Portland-cement concrete with : slumps less than 5 1 mm (2 in) were investigated. Four potential methods to determine the : workability of concrete were proposed for evaluation and development....
Influence of polymer fibers on rheological properties of cement mortars
NASA Astrophysics Data System (ADS)
Malaszkiewicz, Dorota
2017-10-01
The reinforcing effect of fibers in cement composites often results in the improvement of the brittle nature of cementitious materials. But the decrease in the workability of fresh concrete is often the disadvantage of fibers addition. Conventional single-point workability tests cannot characterize workability of concrete in terms of fundamental rheological parameters. To this end, this paper describes an investigation of the influence of synthetic fiber additions (fiber length in the range 12-50 mm and volume fraction in the range 0-4%) on the rheological properties of fiber reinforced fresh mortar (FRFM) and development of these properties over time. The rheometer Viskomat XL was used in this study. Within the limitations of the instrument and testing procedure it is shown that FRFMs conform to the Bingham model. Natural postglacial sand 0/4 mm was used as a fine aggregate and cement CEMI 42.5 R was used as a binder. Three commercial synthetic fibers were selected for these examinations. Rheological properties were expressed in terms of Bingham model parameters g (yield value ) and h (plastic viscosity). Based on the test results it was found out that the fiber type and volume fraction affected both the yield stress and plastic viscosity.
New class of thermosetting plastics has improved strength, thermal and chemical stability
NASA Technical Reports Server (NTRS)
Burns, E. A.; Dubrow, B.; Lubowitz, H. R.
1967-01-01
New class of thermosetting plastics has high hydrocarbon content, high stiffness, thermal stability, humidity resistance, and workability in the precured state. It is designated cyclized polydiene urethane, and is applicable as matrices to prepare chemically stable ablative materials for rocket nose cones of nozzles.
Elusive '68: The Challenge to Pedagogy
ERIC Educational Resources Information Center
Donahue, William Collins
2008-01-01
Teaching '68 presents pedagogical challenges far greater than assembling a set of workable classroom materials. Divisive controversies that were the hallmark of the time--e.g., the debate over the nature and appropriate use of violence--are with us still, though in a somewhat different form. Further, the instructor's own politics and positionality…
A Study of Tungsten-Technetium Alloys
NASA Technical Reports Server (NTRS)
Maltz, J. W.
1965-01-01
Technetium is a sister element to rhenium and has many properties that are similar to rhenium. It is predicted that technetium will have about the same effects on tungsten as rhenium in regard to increase in workability, lowered ductile to brittle transition temperature, and improved ductility. The objectives of the current work are to recover technetium from fission product wastes at Hanford Atomic Products Operation and reduce to purified metal; prepare W-Tc alloys containing up to 50 atomic% Tc; fabricate the alloy ingots to sheet stock, assessing the effect of technetium on workability; and perform metallurgical and mechanical properties evaluation of the fabricated alloys. Previous reports have described the separation and purification of 800 g of technetium metal powder, melting of technetium and W-Tc alloys, and some initial observation of the alloy material.
DOT National Transportation Integrated Search
2015-03-01
Due to the low workability of slipform concrete mixtures, the science of rheology is not strictly applicable for such concrete. However, : the concept of rheological behavior may still be considered useful. A novel workability test method (Vibrating ...
Work-ability evaluation: a piece of cake or a hard nut to crack?
Slebus, Frans G; Sluiter, Judith K; Kuijer, P Paul F M; Willems, J Han H B M; Frings-Dresen, Monique H W
2007-08-30
To describe what aspects, categorized according to the ICF model, insurance physicians (IPs) take into account in assessing short- and long-term work-ability. An interview study on a random sample of 60 IPs of the Dutch National Institute for Employee Benefit Schemes, stratified by region and years of experience. In determining work-ability, a wide range of aspects were used. In the case of musculoskeletal disease, 75% of the IPs considered the 'function and structures' component important. With psychiatric and other diseases, however, the 'participation factor' component was considered important by 85 and 80%, respectively. Aspects relating to the 'environmental factor' and 'personal factor' components were mentioned as important by fewer than 25%. In assessing the short- and long-term prognosis of work-ability, the 'disease or disorder' component was primarily used with a rate of over 75%. In determining work-ability, insurance physicians predominantly consider aspects relating to the 'functions and structures' and 'participation' components of the ICF model important. The 'environmental factor' and 'personal factor' components were not often mentioned. In assessing the short- and long-term prognosis of work-ability, the 'disease or disorder' component was predominantly used. It can be argued that 'environmental factors' and 'personal factors' should also more often be used in assessing work-ability.
48 CFR 1552.215-72 - Instructions for the Preparation of Proposals.
Code of Federal Regulations, 2010 CFR
2010-10-01
..., “Payments Under Time and Materials and Labor-Hour Contracts,” include in the cost proposal the estimated... to reflect the Government's estimate of the offeror's probable costs. Any inconsistency, whether real... hours are the workable hours required by the Government and do not include release time (i.e., holidays...
Budgeting: The Basics and Beyond. Learn at Home.
ERIC Educational Resources Information Center
Prochaska-Cue, Kathy; Sugden, Marilyn
Designed as an at-home course to help users develop a realistic budget plan and set up a workable record-keeping system, these course materials provide practical tips, ideas, and suggestions for budgeting. The course begins with a nine-step budgeting process which emphasizes communicating among family members, considering personal or family…
Study of Fresh and Hardening Process Properties of Gypsum with Three Different PCM Inclusion Methods
Serrano, Susana; Barreneche, Camila; Navarro, Antonia; Haurie, Laia; Fernandez, A. Inés; Cabeza, Luisa F.
2015-01-01
Gypsum has two important states (fresh and hardened states), and the addition of phase change materials (PCM) can vary the properties of the material. Many authors have extensively studied properties in the hardened state; however, the variation of fresh state properties due to the addition of Micronal® DS 5001 X PCM into gypsum has been the object of few investigations. Properties in fresh state define the workability, setting time, adherence and shrinkage, and, therefore the possibility of implementing the material in building walls. The aim of the study is to analyze, compare and evaluate the variability of fresh state properties after the inclusion of 10% PCM. PCM are added into a common gypsum matrix by three different methods: adding microencapsulated PCM, making a suspension of PCM/water, and incorporating PCM through a vacuum impregnation method. Results demonstrate that the inclusion of PCM change completely the water required by the gypsum to achieve good workability, especially the formulation containing Micronal® DS 5001 X: the water required is higher, the retraction is lower (50% less) due to the organic nature of the PCM with high elasticity and, the adherence is reduced (up to 45%) due to the difference between the porosity of the different surfaces as well as the surface tension difference. PMID:28793584
Morelock, Jeremiah C; McNamara, Tay K; James, Jacquelyn B
2017-11-01
This article investigates the effect of an intervention on the workability of older adults (i.e., the competence, health, and other mental and physical characteristics that workers need to meet the demands of their jobs). We used data from health care workers ( N = 437) who participated in a "time and place management" (TPM) intervention. Although related to flexible work options that aim to give workers more choice and control over the time and place of their work, TPM is conceptually distinct in that it focuses on the processes and guidelines necessary to the successful management of choice and control rather than the options alone. We focused on how the TPM intervention moderated the relationship between age and workability over time, with a particular focus on variation by baseline workability. Our results indicated that the intervention can benefit older workers with low workability.
1988-02-12
experimentally , a pulsed power system com- prising separate anode and cathode pulsers was designed and assembled. A double diode was developed to produce...be closed. To initiate this assessment, Mission Research Corporation (MRC) performed a two-year primarily experimental investigation of non - neutral...through from the cathode nad to be designed . Experimentation with several materials and setups produced a workable design , using nylon stocking hose
Relating Fresh Concrete Viscosity Measurements from Different Rheometers
Ferraris, Chiara F.; Martys, Nicos S.
2003-01-01
Concrete rheological properties need to be properly measured and predicted in order to characterize the workability of fresh concrete, including special concretes such as self-consolidating concrete (SCC). It was shown by a round-robin test held in 2000 [1,2] that different rheometer designs gave different values of viscosity for the same concrete. While empirical correlation between different rheometers was possible, for a procedure that is supposed to “scientifically” improve on the empirical slump tests, this situation is unsatisfactory. To remedy this situation, a new interpretation of the data was developed. In this paper, it is shown that all instruments tested could be directly and quantitatively compared in terms of relative plastic viscosity instead of the plastic viscosity alone. This should eventually allow the measurements from various rheometer designs to be directly calibrated against known standards of plastic viscosity, putting concrete rheometry and concrete workability on a sounder materials science basis. PMID:27413607
Some engineering properties of heavy concrete added silica fume
DOE Office of Scientific and Technical Information (OSTI.GOV)
Akkaş, Ayşe; Başyiğit, Celalettin; Esen, Serap
Many different types of building materials have been used in building construction for years. Heavy concretes can be used as a building material for critical building as it can contain a mixture of many heavy elements. The barite itself for radiation shielding can be used and also in concrete to produce the workable concrete with a maximum density and adequate structural strength. In this study, some engineering properties like compressive strength, elasticity modules and flexure strength of heavy concretes’ added Silica fume have been investigated.
Mechanical and Physical Performance of Concrete Including Waste Electrical Cable Rubber
NASA Astrophysics Data System (ADS)
Taner Yildirim, Salih; Pelin Duygun, Nur
2017-10-01
Solid wastes are important environmental problem all over the World. Consumption of the plastic solid waste covers big portion within the total solid waste. Although a numerous plastic material is subjected to the recycling process, it is not easy to be destroyed by nature. One of the recommended way to prevent is to utilize as an aggregate in cement-based material. There are many researches on use of recycling rubber in concrete. However, studies on recycling of waste electrical cable rubber (WECR) in concrete is insufficient although there are many research on waste tyre rubbers in concrete. In this study, fine aggregate was replaced with WECR which were 5%, 10%, and 15 % of the total aggregate volume in the concrete and researched workability, unit weight, water absorption, compressive strength, flexural strength, ultrasonic pulse velocity, modulus of elasticity, and abrasion resistance of concrete. As a result of experimental studies, increase of WECR amount in concrete increases workability due to lack of adherence between cement paste and WECR, and hydrophobic structure of WECR while it influences negatively mechanical properties of concrete. It is possible to use WECR in concrete taking into account the reduction in mechanical properties.
Rheological and Mechanical Response Modifications for a Self-Leveling Mortar
NASA Astrophysics Data System (ADS)
Katsiadramis, N. J.; Sotiropoulou, A. B.; Pandermarakis, Z. G.
2010-06-01
In many cases cement based materials demand a higher flowability and workability and this conventionally can’t be done without loss of its strength, due to the fact that the common practice to increase the workability is the addition of water. But, nowadays using a third generation superplasticizer (SP) we can achieve the desire flowability without loss of its strength. The action of superplastisizers is to spread efficiently the cement grains and so to wetting better the cement grains giving a more homogeneous mixture with higher strength. Nine different mixtures were prepared adding a small percentage of SP (1%). The conditions to get a self levelling mortar, have to do not only with rheological but also with mechanical demands. The bending and compression test gave the achieving mechanical strength whereas their rheological response came through slump flow and v-funnel flow tests. With the help of a small amount of stabilizer we obtain a robust mixture that deserves the desire response at the field too.
NASA Technical Reports Server (NTRS)
Fleming, J. R.
1979-01-01
Testing of low cost low suspension power slurry vehicles is presented. Cutting oils are unlikely to work, but a mineral oil with additives should be workable. Two different abrasives were tested. A cheaper silicon carbide from Norton gave excellent results except for excessive kerf loss: the particles were too big. An abrasive treated for lubricity showed no lubricity improvement in mineral oil vehicle. The bounce fixture was tested for the first time under constant cut rate conditions (rather than constant force). Although the cut was not completed before the blades broke, the blade lifetime of thin (100 micrometer) blades was 120 times the lifetime without the fixture. The large prototype saw completed a successful run, producing 90% cutting yield (849 wafers) at 20 wafers/cm. Although inexperience with large numbers of wafers caused cleaning breakage to reduce this yield to 74%, the yield was high enough that the concept of the large saw is proven workable.
Optimum mix for fly ash geopolymer binder based on workability and compressive strength
NASA Astrophysics Data System (ADS)
Arafa, S. A.; Ali, A. Z. M.; Awal, A. S. M. A.; Loon, L. Y.
2018-04-01
The request of concrete is increasing every day for sustaining the necessity of development of structure. The production of OPC not only consumes big amount of natural resources and energy, but also emit significant quantity of CO2 to the atmosphere. Therefore, it is necessary to find alternatives like Geopolymer to make the concrete environment friendly. Geopolymer is an inorganic alumino-silicate compound, produced from fly ash. This paper describes the experimental work conducted by casting 40 geopolymer paste mixes, and was cured at 80°C for 24 h to evaluate the effect of various parameters affecting the workability and compressive strength. Alkaline solution to fly ash ratio and sodium hydroxide (NaOH) concentration were chosen as the key parameters of strength and workability. Laboratory investigation with different percentage of sodium hydroxide concentration and different alkaline liquid to fly ash ratio reveals that the optimum ratios are 10 M, AL/FA=0.5. It has generally been found that the workability decreased and the compressive strength increased with an increase in the concentration of sodium hydroxide solution. However, workability was increased and the compressive strength was decreased with the increase in the ratio of fly ash to alkaline solution.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-20
... to develop a workable test to apply these principles that is clear, concise, administratively... was made available to researchers on generous terms. The USPTO seeks to develop a workable test to...
Morgan, Matthew M; Piers, Warren E
2016-04-14
Polycyclic aromatic hydrocarbons in which one or more CC units have been replaced by isoelectronic BN units have attracted interest as potentially improved organic materials in various devices. This promise has been hampered by a lack of access to gram quantities of these materials. However, the exploitation of keystone reactions such as ring closing metathesis, borylative cyclization of amino styrenes and electrophilic borylation has lead to strategies for access to workable amounts of material. These strategies can be augmented by judicious postfunctionalization reactions to diversify the library of materials available. This Frontier article highlights some of the recent successes and shows that the long promised applications of BN-doped PAHs are beginning to be explored in a meaningful way.
[Study on extraction process of Radix Bupleuri].
Zhao, Lei; Liu, Benliang; Wu, Fuxiang; Tao, Lanping; Liu, Jian
2004-10-01
The orthogonal design was used to optimize extraction process of Radix Bupleuri with content of total saponin and yield of the extract as markers. Factors that have been chosen were ethanol concentration, ethanol consumption, extraction times and extraction time. Each factor had three levels. The result showed that the optimum extraction condition was 80% ethanol, 4 times the amount of material, refluxing for 4 times, 60 minutes each time. The optimized process was stable and workable.
ERIC Educational Resources Information Center
TRAVERS, ROBERT M.W.
THE REVIEWER FAULTS THE AUTHOR FOR "SIMPLE AND UNCRITICAL PRESENTATIONS OF IDEAS" THAT FAIL TO RESULT IN THE PROMISED "WORKABLE DOCUMENT FOR PRACTICING TEACHER EDUCATORS TO USE." THE MATERIAL "SHOWS SO COMPLETE A LACK OF CONCERN FOR SUCH MATTERS AS WHETHER A MODEL HAS OR HAS NOT BEEN DERIVED FROM EMPIRICAL RESEARCH, WHETHER THE MODEL HAS OR HAS…
In-Vehicle Safety Advisory And Warning System (Ivsaws), Volume II: Final Report
DOT National Transportation Integrated Search
2001-04-01
Methods for determining the workability of freshly mixed portland-cement concrete with slumps less than 51 mm (2 in) were investigated. Four potential methods to determine the workability of concrete were proposed for evaluation and development. The ...
Kitajima, Sakihito; Kamei, Kaeko; Nishitani, Maiko; Sato, Hiroyuki
2010-01-01
Clay wall (tsuchikabe in Japanese) material for Japanese traditional buildings is manufactured by fermenting a mixture of clay, sand, and rice straw. The aim of this study was to understand the fermentation process in order to gain insight into the ways waste biomass can be used to produce useful materials. In this study, in addition to Clostridium, we suggested that the family Nectriaceae and the Scutellinia sp. of fungi were important in degrading cell wall materials of rice straw, such as cellulose and/or lignin. The microorganisms in the clay wall material produced sulfur-containing inorganic compounds that may sulfurate minerals in clay particles, and polysaccharides that give viscosity to clay wall material, thus increasing workability for plastering, and possibly giving water-resistance to the dried clay wall.
Workability of hot mix asphalt
DOT National Transportation Integrated Search
2003-04-01
Workability in the field can be defined as a property that describes the ease with which hot mix asphalt (HMA) can be placed, worked by hand and compacted. Use of polymer-modified binders has increase in the U.S. due to the resultant performance bene...
Optimization of agricultural field workability predictions for improved risk management
USDA-ARS?s Scientific Manuscript database
Risks introduced by weather variability are key considerations in agricultural production. The sensitivity of agriculture to weather variability is of special concern in the face of climate change. In particular, the availability of workable days is an important consideration in agricultural practic...
Effects of Different Mineral Admixtures on the Properties of Fresh Concrete
Nuruddin, Muhammad Fadhil; Shafiq, Nasir
2014-01-01
This paper presents a review of the properties of fresh concrete including workability, heat of hydration, setting time, bleeding, and reactivity by using mineral admixtures fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA). Comparison of normal and high-strength concrete in which cement has been partially supplemented by mineral admixture has been considered. It has been concluded that mineral admixtures may be categorized into two groups: chemically active mineral admixtures and microfiller mineral admixtures. Chemically active mineral admixtures decrease workability and setting time of concrete but increase the heat of hydration and reactivity. On the other hand, microfiller mineral admixtures increase workability and setting time of concrete but decrease the heat of hydration and reactivity. In general, small particle size and higher specific surface area of mineral admixture are favourable to produce highly dense and impermeable concrete; however, they cause low workability and demand more water which may be offset by adding effective superplasticizer. PMID:24701196
Effects of different mineral admixtures on the properties of fresh concrete.
Khan, Sadaqat Ullah; Nuruddin, Muhammad Fadhil; Ayub, Tehmina; Shafiq, Nasir
2014-01-01
This paper presents a review of the properties of fresh concrete including workability, heat of hydration, setting time, bleeding, and reactivity by using mineral admixtures fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA). Comparison of normal and high-strength concrete in which cement has been partially supplemented by mineral admixture has been considered. It has been concluded that mineral admixtures may be categorized into two groups: chemically active mineral admixtures and microfiller mineral admixtures. Chemically active mineral admixtures decrease workability and setting time of concrete but increase the heat of hydration and reactivity. On the other hand, microfiller mineral admixtures increase workability and setting time of concrete but decrease the heat of hydration and reactivity. In general, small particle size and higher specific surface area of mineral admixture are favourable to produce highly dense and impermeable concrete; however, they cause low workability and demand more water which may be offset by adding effective superplasticizer.
Tomasek, Bradley J; Williams, Martin M; Davis, Adam S
2017-01-01
As weather patterns become more volatile and extreme, risks introduced by weather variability will become more critical to agricultural production. The availability of days suitable for field work is driven by soil temperature and moisture, both of which may be altered by climate change. We projected changes in Illinois season length, spring field workability, and summer drought risk under three different emissions scenarios (B1, A1B, and A2) down to the crop district scale. Across all scenarios, thermal time units increased in parallel with a longer frost-free season. An increase in late March and Early April field workability was consistent across scenarios, but a decline in overall April through May workable days was observed for many cases. In addition, summer drought metrics were projected to increase for most scenarios. These results highlight how the spatial and temporal variability in climate change may present unique challenges to mitigation and adaptation efforts.
[Studies on extraction process of Radix Platycodi].
Wu, Biyuan; Sun, Jun; Jiang, Hongfang
2002-06-01
The orthogonal design was used to optimize the extraction process of Radix Platycodi with content of total saponin and yield of the extract as markers. Factors that have been chosen were alcohol concentration, alcohol consumption, extraction times and extraction time. Each factor has three levels. The result showed that the optimum extraction condition obtained was 70% alcohol, 3 times the amount of material, refluxing for 5 times, 60 minutes each time, the optimized process was stable and workable.
Electromagnetic density of modes for a finite-size three-dimensional structure.
D'Aguanno, Giuseppe; Mattiucci, Nadia; Centini, Marco; Scalora, Michael; Bloemer, Mark J
2004-05-01
The concept of the density of modes has been lacking a precise mathematical definition for a finite-size structure. With the explosive growth in the fabrication of photonic crystals and nanostructures, which are inherently finite in size, a workable definition is imperative. We give a simple and physically intuitive definition of the electromagnetic density of modes based on the Green's function for a generic three-dimensional open cavity filled with a linear, isotropic, dielectric material.
Workability of glass reinforced concrete (GRC) with granite and silica sand aggregates
NASA Astrophysics Data System (ADS)
Moceikis, R.; Kičaitė, A.; Keturakis, E.
2017-10-01
Glass fiber reinforced concrete (GRC) opens the door for lightweight and complex shaped innovative construction, adding architectural value to buildings. With panel thickness down to 15 mm, considerable amount of total loads and materials per square meter of facade can be saved, if compared to conventionally used 80 mm thickness outer layer in insulated precast concrete wall elements. Even though GRC is used for over 50 years in such countries as Great Britain, USA and Japan, there are very few examples and little research done in Eastern Europe with this building material. European Commission propagates sustainable design as commitment to energy efficiency, environmental stewardship and conservation. For this reason, GRC plays important role in mowing toward these goals. In this paper, GRC premix recipes including fine granite and silica sands, reinforced with 13mm length alkali resistant glass fibers are investigated. Two CEM I 52,5R cements with different particle sizes were used and severe water dissociation noticed in one of concrete mixes. Cement particle size distribution determined with laser diffraction particle analyser Cilas 1090LD. To determine modulus of rupture (M.O.R.) and limit of proportionality (L.O.P), plates thickness 15 and 20 mm were produced and tested for flexural resistance according to 4-point bending scheme. Concrete workability tests were made according EN 1170-1.
Compressive strength of marine material mixed concrete
NASA Astrophysics Data System (ADS)
Adnan; Parung, H.; Tjaronge, M. W.; Djamaluddin, R.
2017-11-01
Many cement factories have been incorporated fly ash with clinker cement to produce blended cement. PCC is a type of blended cement incorporated fly ash that produced in Indonesia cement factories. To promote the sustainable development in the remote islands this present paper attempted to study the suitability of sea water, marine sand that available abundantly surround the remote island with Portland Composite Cement (PCC) and crushed river stone to produce concrete. Slump test was conducted to evaluate the workability of fresh concrete and also compressive strength with stress-strain relationship was carried out to evaluate the hardened concrete that cured with two curing condition (e.g. sea water curing, and tap water-wet burlap curing). Test result indicated that fresh concrete had proper workability and all hardened specimens appeared a good compaction result. Compressive strength of specimens cured which sea water was higher than the specimens which cured by tap water-wet burlap where stress-strain behavior of specimens made with sea water, marine sand, and PCC had similar behavior with specimens which made with PCC and tap water.
Razi, Putri Zulaiha; Abdul Razak, Hashim; Khalid, Nur Hafizah A
2016-05-06
This study investigates the engineering performance and CO₂ footprint of mortar mixers by replacing Portland cement with 10%, 20%, 40% and 60% fly ash, a common industrial waste material. Samples of self-compacting mortar (SCM) were prepared with four different water/binder ratios and varying dosages of superplasticizer to give three ranges of workability, i.e. , normal, high and self-compacting mortar mix. The engineering performance was assessed in term of compressive strength after designated curing periods for all mixes. CO₂ footprint was the environmental impact indicator of each production stage. The optimum mix obtained was at 10% replacement rate for all mixes. Total production emission reduced by 56% when the fly ash replacement rate increased from 0% to 60% (maximum). This is translated to a reduction of 80% in eco-points (assuming that the energy consumption rate of production with 0% fly ash is at 100%). Such re-utilization is encouraged since it is able to reduce possible soil toxicity due to sulfur leaching by 5% to 27% and landfill area by 15% to 91% on average.
NASA Astrophysics Data System (ADS)
Liu, Yang; Geng, Cong; Zhu, Yunke; Peng, Jinfeng; Xu, Junrui
2017-04-01
Using a controlled thermal simulator system, hybrid carbon nanotube-aluminum reinforced ZA27 composites were subjected to hot compression testing in the temperature range of 473-523 K with strain rates of 0.01-10 s-1. Based on experimental results, a developed-flow stress model was established using a constitutive equation coupled with strain to describe strain softening arising from dynamic recrystallization. The intrinsic workability was further investigated by constructing three-dimensional (3D) processing maps aided by optical observations of microstructures. The 3D processing maps were constructed based on a dynamic model of materials to delineate variations in the efficiency of power dissipation and flow instability domains. The instability domains exhibited adiabatic shear band and flow localization, which need to be prevented during hot processing. The recommended domain is predicated to be within the temperature range 550-590 K and strain rate range 0.01-0.35 s-1. In this state, the main softening mechanism is dynamic recrystallization. The results from processing maps agree well with the microstructure observations.
Razi, Putri Zulaiha; Abdul Razak, Hashim; Khalid, Nur Hafizah A.
2016-01-01
This study investigates the engineering performance and CO2 footprint of mortar mixers by replacing Portland cement with 10%, 20%, 40% and 60% fly ash, a common industrial waste material. Samples of self-compacting mortar (SCM) were prepared with four different water/binder ratios and varying dosages of superplasticizer to give three ranges of workability, i.e., normal, high and self-compacting mortar mix. The engineering performance was assessed in term of compressive strength after designated curing periods for all mixes. CO2 footprint was the environmental impact indicator of each production stage. The optimum mix obtained was at 10% replacement rate for all mixes. Total production emission reduced by 56% when the fly ash replacement rate increased from 0% to 60% (maximum). This is translated to a reduction of 80% in eco-points (assuming that the energy consumption rate of production with 0% fly ash is at 100%). Such re-utilization is encouraged since it is able to reduce possible soil toxicity due to sulfur leaching by 5% to 27% and landfill area by 15% to 91% on average. PMID:28773465
Nuclear weapons are illegal threats
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyrowitz, E.L.
Challenging Harry Almond's position that nuclear deterrence is workable, the author contends that there is no historical basis for believing that anticipation of the horrors of war will be an effective deterrent. He questions the belief that the nuclear balance of terror has maintained the peace for the past 40 years because an arms race is inherently unstable. The argument that the pursuit of national interests takes precedence over any limitation imposed by international law reflects a perception of international law that is comparable to the Third Reich. The bases for a legal evaluation of the status of nuclear weaponsmore » under international law come from express and implicit treaty provisions, international custom, general principles of international law, judicial decisions, resolutions at the United Nations, and the opinions of qualified jurists as well as military necessity.« less
Application of P.O and R-SAC mortar for 3D printing in construction
NASA Astrophysics Data System (ADS)
Lin, J. C.; Wu, X.; Yang, W.; Zhao, R. X.; Qiao, L. G.
2018-01-01
Compared with traditional properties of building materials, 3D printing materials should have controllable setting time, appropriate workability and superior mechanical properties. Adaptability of two types of cementitious system on the 3D printing were investigated in this paper. Results showed that both of them can match of 3D printing process with the working window time required (10-90min) by using the compound adjustable solidification agents, which have the high mechanical properties (3d⩾30MPa, 28d> 63MPa), and appropriate suitable parameter range of fluidity (R-SAC:210-240mm,P.O:200-220mm).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malobabic, Sina; Jupe, Marco; Ristau, Detlev
Nowadays, Ion Beam Sputter (IBS) processes are very well optimized on an empirical basis. To achieve further progresses, a modification of the IBS process by guiding the coating material using an axial magnetic field and an additional electrical field has been studied. The electro-magnetic (EM) field leads to a significant change in plasma properties and deposition rate distributions, whereas an increase in deposition rate along the centerline of the axial EM field around 150% was observed. These fundamental studies on the prototype are the basis for the development of an applicable and workable design of a separation device.
Fatigue and fracture: Overview
NASA Technical Reports Server (NTRS)
Halford, G. R.
1984-01-01
A brief overview of the status of the fatigue and fracture programs is given. The programs involve the development of appropriate analytic material behavior models for cyclic stress-strain-temperature-time/cyclic crack initiation, and cyclic crack propagation. The underlying thrust of these programs is the development and verification of workable engineering methods for the calculation, in advance of service, of the local cyclic stress-strain response at the critical life governing location in hot section compounds, and the resultant crack initiation and crack growth lifetimes.
Preparation of low strategic metal content superalloys
NASA Technical Reports Server (NTRS)
Sczerzenie, F. E.; Maurer, G. E.
1982-01-01
The properties of modified NIMONIC 115 and UDIMET 720 with reduced levels of cobalt were evaluated. Vacuum induction melted and vacuum arc remelted ingots were hot rolled to 3/4 inch diameter bar. Hot workability was evaluated in terms of the ingot rolling behavior and the hot ductility of the as-rolled bar. Variations in workability and bar ductility were correlated to variations in incipient melting temperature and gamma prime solvus, both of which varied with cobalt content. Heat treatments were defined to yield, as far as possible, similar structures from alloy to alloy. At the lowest cobalt levels N-115 workability was severely limited and the alloys could not be worked to bar. It is suggested that incipient melting in combination with heavy grain boundary carbide precipitation reduced ingot workability. Final heat treatment of modified alloys was difficult in the situation where the gamma prime solvus temperature was close to the incipient melting point, indicating that it may not be feasible to fully solution low cobalt alloys to obtain the large grain size required for optimum creep resistance.
Extrinsic Contribution and Instability Properties in Lead-Based and Lead-Free Piezoceramics
García, José Eduardo
2015-01-01
Piezoceramic materials generally exhibit a notable instability of their functional properties when they work under real external conditions. This undesirable effect, known as nonlinear behavior, is mostly associated with the extrinsic contribution to material response. In this article, the role of the ferroelectric domain walls’ motion in the nonlinear response in the most workable lead-based and lead-free piezoceramics is reviewed. Initially, the extrinsic origin of the nonlinear response is discussed in terms of the temperature dependence of material response. The influence of the crystallographic phase and of the phase boundaries on the material response are then reviewed. Subsequently, the impact of the defects created by doping in order to control the extrinsic contribution is discussed as a way of tuning material properties. Finally, some aspects related to the grain-size effect on the nonlinear response of piezoceramics are surveyed. PMID:28793681
Aggregate assesment and durability evaluation of optimized graded concrete in the state of Oklahoma
NASA Astrophysics Data System (ADS)
Ghaeezadeh, Ashkan
This research is a part of a larger project that emphasizes on creating a more scientific approach to designing concrete mixtures for concrete pavements that use less cement and more aggregate which is called optimized graded concrete. The most challenging obstacle in optimized mixtures is reaching enough workability so that one doesn't have to add more cement or super-plasticizer to reach the desired level of flowability. Aggregate gradation and characteristics have found to be very important when it comes to the workabaility of optimized graded concrete. In this research a new automated method of aggregate assessment was used to compare the shape and the surface of different aggregates as well as their influence on the concrete flowability. At the end, the performance of optimized graded concrete against drying shrinkage and freezing and thawing condition were investigated.
Effect of Admixtures on the Yield Stresses of Cement Pastes under High Hydrostatic Pressures
Yim, Hong Jae; Kim, Jae Hong; Kwon, Seung Hee
2016-01-01
When cement-based materials are transported at a construction site, they undergo high pressures during the pumping process. The rheological properties of the materials under such high pressures are unknown, and estimating the workability of the materials after pumping is a complex problem. Among various influential factors on the rheology of concrete, this study investigated the effect of mineral and chemical admixtures on the high-pressure rheology. A rheometer was fabricated that could measure the rheological properties while maintaining a high pressure to simulate the pumping process. The effects of superplasticizer, silica fume, nanoclay, fly ash, or ground granulated blast furnace slag were investigated when mixed with two control cement pastes. The water-to-cement ratios were 0.35 and 0.50. PMID:28773273
Utilization of fly ash as partial sand replacement in oil palm shell lightweight aggregate concrete
NASA Astrophysics Data System (ADS)
Nazrin Akmal, A. Z. Muhammad; Muthusamy, K.; Mat Yahaya, F.; Hanafi, H. Mohd; Nur Azzimah, Z.
2017-11-01
Realization on the increasing demand for river sand supply in construction sector has inspired the current research to find alternative material to reduce the use of natural sand in oil palm shell lightweight aggregate concrete (OPS LWAC) production. The existence of fly ash, a by-product generated from coal power plant, which pose negative impact to the environment when it is disposed as waste, were used in this research. The effect of fly ash content as partial sand replacement towards workability and compressive strength of OPS lightweight aggregate concrete were investigated. Four concrete mixes containing various percentage of fly ash that are 0%, 10%, 20% and 30% by weight of sand were used in the experimental work. All mixes were cast in form of cubes before subjected to water curing until the testing age. Compressive strength test were conducted at 1, 3, 7 and 28 days. The finding shows that the workability of the OPS LWAC decreases when more fly ash are used as sand replacement. It was found that adding of 10% fly ash as sand replacement content resulted in better compressive strength of OPS LWAC, which is higher than the control mix.
Casting of superconducting composite materials (M-4)
NASA Technical Reports Server (NTRS)
Togano, Kazumasa
1993-01-01
An aluminum-lead-bismuth alloy is a flexible alloy and is promising for easily workable embedded-type, filament-dispersed superconducting wire material. It is difficult to produce homogeneous ingots of this material because it is easily separated into elements when melted on Earth due to the large specific gravity differences. In this experiment, a homogeneous alloy will first be produced in molten state in microgravity. It will then be returned to Earth and processed into a wire or tape form. It will then be dispersed as the second phase in micro texture form into the primary phase of aluminum. Superconducting wire material with high-critical-magnetic-field characteristics will be produced. The texture of the material will be observed, and its performance will be evaluated. In addition to the above alloy, a four-element alloy will be produced from silver, a rare Earth element, barium, and copper. The alloys will be oxidized and drawn into wire after being returned to Earth. The materials are expected to be forerunners in obtaining superconducting wire materials from oxide superconductors.
Is There a "Workable" Race-Neutral Alternative to Affirmative Action in College Admissions?
ERIC Educational Resources Information Center
Long, Mark C.
2015-01-01
The 2013 decision by the U.S. Supreme Court in the Fisher v. University of Texas at Austin case clarified when and how it is legally permissible for universities to use an applicant's race or ethnicity in its admissions decisions. The court concluded that such use is permissible when "no workable race-neutral alternatives would produce…
NASA Astrophysics Data System (ADS)
Akhlaghi, Omid; Menceloglu, Yusuf Ziya; Akbulut, Ozge
2017-01-01
Calcium aluminate cement (CAC) suffers from loss of workability in less than an hour (~15 minutes) after first touch of water. Current superplasticizers that are utilized to modify the viscosity of cement admixtures are designed to target ordinary Portland cement (OPC). The high affinity between these superplasticizers and cement particles were found to be detrimental in CAC systems. Utilization of a monomer that, instead, facilitates gradual adsorption of a superplasticizer provides workability retention. For the first time in literature, we report a superplasticizer that caters to the properties of CAC such as high rate of surface development and surface charge. While neat CAC was almost unworkable after 1 hour, with the addition of only 0.4% of the optimized superplasticizer, 90% fluidity retention was achieved.
A single cell penetration system by ultrasonic driving
NASA Astrophysics Data System (ADS)
Zhou, Zhaoying; Xiao, Mingfei; Yang, Xing; Wu, Ting
2008-12-01
The researches of single cell's control and operation are the hotspots in whole world. Among the various technologies, the transmission of ectogenic genetic materials between cell membrane is very significant. Imitating the Chinese traditional acupuncture therapy, a new ultrasonic resonance driving method, is imported to drive a cell's penetration probe. A set of the single cell penetration system was established to perform this function. This system includes four subsystems: driving part, micromanipulation part, observation and measurement part, and actuation part. Some fish egg experiments indicate that this system is workable and effective.
Design and Implementation of the PMS Module for ’Argos’
1989-12-01
designing , and implementing a fully workable Planned Maintenance System (PMS). This implementation demonstrates both the capabilities and benefits such a...analyzing, designing , and implementing a fully workable Planned Maintenance System (PMS). This implementation demonstrates both the capabilities and... design and implementation. PMS is the system developed by the navy to provide each ship, department, and supervisor with the tools needed to plan
ERIC Educational Resources Information Center
Ayodele, Rachael B.; Olubayo-Fatiregun, Martina A.
2013-01-01
This study determined the workability of Safety Education and Training for Workers' strategy in reducing accidents. A descriptive survey research design was used. A total of 20 Managerial staff with mean work experience of 13.5 years was selected from 10 manufacturing industries in Lagos State, using intact group method. They were 100% males. Data…
Moosberg, Helena; Lagerblad, Björn; Forssberg, Eric
2003-02-01
This investigation has been made in order to make it possible to increase the use of by-products in cement-based materials. Use of by-products requires a screening procedure that will reliably determine their impact on concrete. A test procedure was developed. The most important properties were considered to be strength development, shrinkage, expansion and workability. The methods used were calorimetry, flow table tests, F-shape measurements, measurements of compressive and flexural strength and shrinkage/expansion measurements. Scanning electron microscopy was used to verify some results. Twelve by-products were collected from Swedish metallurgical and mineral industries and classified according to the test procedure. The investigation showed that the test procedure clearly screened out the materials that can be used in the production of concrete from the unsuitable ones.
Hearing loss and work participation: a cross-sectional study in Norway.
Svinndal, Elisabeth Vigrestad; Solheim, Jorunn; Rise, Marit By; Jensen, Chris
2018-04-27
To study work participation of persons with hearing loss, and associations with hearing disabilities, self-reported workability, fatigue and work accommodation. Cross-sectional internet-based survey. A total of 10,679 persons with hearing loss within working-age were invited to answer the survey, where 3330 answered (35.6%). Degree of hearing loss was associated with low workability, fatigue and work place accommodation, while sick leave was associated with fatigue. Degree of hearing loss was positively associated with being unemployed (p < .001) and having part-time work (p < .01) (often combined with disability benefits) for women. Work place accommodation was more frequently provided among respondents working with sedentary postures, high seniority, long-term sick leave or low workability. Additional unfavourable sensory conditions were associated with decreased employment (p < .001) and workability, and an increase in sick leave (p < .01) and fatigue (p < .001). Hearing loss seemed to influence work participation factors negatively; particularly, for moderate hearing loss and for women, even though the degree of employment was high. A lack of work place accommodation when there was a need for such was found. This implies increased attentiveness towards individual needs concerning the experienced disability a hearing loss may produce. A more frequent use of hearing disability assessment is suggested.
NASA Astrophysics Data System (ADS)
Muthusamy, K.; Zamri, N. A.; Kusbiantoro, A.; Lim, N. H. A. S.; Ariffin, M. A. Mohd
2018-04-01
Both palm oil fuel ash (POFA) and palm oil boiler stone (POBS) are by-products which has been continuously generated by local palm oil mill in large amount. Both by products is usually disposed as profitless waste and considered as nuisance to environment. The present research investigates the workability and compressive strength performance of lightweight aggregate concrete (LWAC) made of palm oil boiler stone (POBS) known as palm oil boiler stone lightweight aggregate concrete (POBS LWAC) containing various content of palm oil fuel ash. The control specimen that is POBS LWAC of grade 60 were produced using 100% OPC. Then, another 4 mixes were prepared by varying the POFA percentage from 10%, 20%, 30% and 40% by weight of cement. Fresh mixes were subjected to slump test to determine its workability before casted in form of cubes. Then, all specimens were subjected to water curing up to 28 days and then tested for its compressive strength. It was found out that utilizing of optimum amount of POFA in POBS LWAC would improve the workability and compressive strength of the concrete. However, inclusion of POFA more than optimum amount is not recommended as it will increase the water demand leading to lower workability and strength reduction.
Negim, El-Sayed; Kozhamzharova, Latipa; Gulzhakhan, Yeligbayeva; Khatib, Jamal; Bekbayeva, Lyazzat; Williams, Craig
2014-01-01
This paper investigates the physicomechanical properties of mortar containing high volume of fly ash (FA) as partial replacement of cement in presence of copolymer latexes. Portland cement (PC) was partially replaced with 0, 10, 20, 30 50, and 60% FA. Copolymer latexes were used based on 2-hydroxyethyl acrylate (2-HEA) and 2-hydroxymethylacrylate (2-HEMA). Testing included workability, setting time, absorption, chemically combined water content, compressive strength, and scanning electron microscopy (SEM). The addition of FA to mortar as replacement of PC affected the physicomechanical properties of mortar. As the content of FA in the concrete increased, the setting times (initial and final) were elongated. The results obtained at 28 days of curing indicate that the maximum properties of mortar occur at around 30% FA. Beyond 30% FA the properties of mortar reduce and at 60% FA the properties of mortar are lower than those of the reference mortar without FA. However, the addition of polymer latexes into mortar containing FA improved most of the physicomechanical properties of mortar at all curing times. Compressive strength, combined water, and workability of mortar containing FA premixed with latexes are higher than those of mortar containing FA without latexes.
Kozhamzharova, Latipa; Gulzhakhan, Yeligbayeva; Bekbayeva, Lyazzat; Williams, Craig
2014-01-01
This paper investigates the physicomechanical properties of mortar containing high volume of fly ash (FA) as partial replacement of cement in presence of copolymer latexes. Portland cement (PC) was partially replaced with 0, 10, 20, 30 50, and 60% FA. Copolymer latexes were used based on 2-hydroxyethyl acrylate (2-HEA) and 2-hydroxymethylacrylate (2-HEMA). Testing included workability, setting time, absorption, chemically combined water content, compressive strength, and scanning electron microscopy (SEM). The addition of FA to mortar as replacement of PC affected the physicomechanical properties of mortar. As the content of FA in the concrete increased, the setting times (initial and final) were elongated. The results obtained at 28 days of curing indicate that the maximum properties of mortar occur at around 30% FA. Beyond 30% FA the properties of mortar reduce and at 60% FA the properties of mortar are lower than those of the reference mortar without FA. However, the addition of polymer latexes into mortar containing FA improved most of the physicomechanical properties of mortar at all curing times. Compressive strength, combined water, and workability of mortar containing FA premixed with latexes are higher than those of mortar containing FA without latexes. PMID:25254256
Chemical Sensors Based on Metal Oxide Nanostructures
NASA Technical Reports Server (NTRS)
Hunter, Gary W.; Xu, Jennifer C.; Evans, Laura J.; VanderWal, Randy L.; Berger, Gordon M.; Kulis, Mike J.; Liu, Chung-Chiun
2006-01-01
This paper is an overview of sensor development based on metal oxide nanostructures. While nanostructures such as nanorods show significan t potential as enabling materials for chemical sensors, a number of s ignificant technical challenges remain. The major issues addressed in this work revolve around the ability to make workable sensors. This paper discusses efforts to address three technical barriers related t o the application of nanostructures into sensor systems: 1) Improving contact of the nanostructured materials with electrodes in a microse nsor structure; 2) Controling nanostructure crystallinity to allow co ntrol of the detection mechanism; and 3) Widening the range of gases that can be detected by using different nanostructured materials. It is concluded that while this work demonstrates useful tools for furt her development, these are just the beginning steps towards realizati on of repeatable, controlled sensor systems using oxide based nanostr uctures.
NASA Astrophysics Data System (ADS)
Turuallo, Gidion; Mallisa, Harun
2018-03-01
The use of waste materials in concrete gave many advantages to prove the properties of concrete such as its workability, strength and durability; as well to support sustaianable development programs. Fly ash was a waste material produced from coal combustion. This research was conducted to find out the effect of fly ash as a part replacement of cement to produce high strength concrete. The fly ash, which was used in this research, was taken from PLTU Mpanau Palu, Central Sulawesi. The water-binder ratio used in this research was 0.3 selected from trial mixes done before. The results of this research showed that the strength of fly ash concretes were higher than concrete with PCC only. The replacement of cement with fly ash concrete could be up to 20% to produce high strength concrete.
Engaging with the political imaginaries of science: Near misses and future targets.
Nowotny, Helga
2014-01-01
The current economic and financial crisis is also a political crisis that requires a rethinking of public engagement with science. In the past, the dominant focus of science, technology and society (STS) has led to a blind spot: political understanding and engagement of policy-makers and politicians with science, which is an integral part of any public engagement. Arguably, it is bound to and emerges from what Ezrahi calls collective political imaginaries. These are necessary fictions, which are causative and performative. In crude form, they manifest themselves in short-term impact measurements of every unit of scientific activity with citizens as the fictitious ultimate beneficiaries. In the future, STS can gain from coming up with a workable definition of the public interest with a focus on the public value of science. It can investigate collective imaginaries as they emerge from interactions with new media. As necessary fictions they may hold answers we never imagined them to hold.
Study on cement mortar and concrete made with sewage sludge ash.
Chang, F C; Lin, J D; Tsai, C C; Wang, K S
2010-01-01
This study investigated the feasibility of reusing wastewater sludge ash in construction materials to replace partial materials. Wastewater sludge sampled from thermal power plant was burned into sludge ash at 800°C in the laboratory. The sludge incineration ash has low heavy metal including Pb, Cd, Cr and Cu, so it belongs to general enterprise waste. The chemical composition of sludge incineration ash was summed up in SiO₂, CaO, Fe₂O₃ and MgO. Then the wastewater sludge ash is also found to be a porous material with irregular surface. When the sludge ash was used to replace mortar or concrete cement, its water-adsorption capability will result in the reduction of mortar workability and compressive strength. Cement is being substituted for sludge ash, and 10 percent of sludge ash is more appropriate. Sludge ash is reused to take the place of construction materials and satisfies the requests of standard specification except for higher water absorption.
NASA Astrophysics Data System (ADS)
Kim, Jeoung Han; Kim, Kyong Min; Yeom, Jong Taek; Young, Sung
2016-03-01
The effect of yttrium (< 5.5 at%) on the martensite-austenite phase transformation temperatures, microstructural evolution, and hot workability of Ti-Ni-Hf high-temperature shape memory alloys is investigated. For these purposes, differential scanning calorimetry, hot compression, and thermo-gravimetric tests are conducted. The phase transformation temperatures are not noticeably influenced by the addition of yttrium up to 4.5 at%. Furthermore, the hot workability is not significantly affected by the yttrium addition up to 1.0 at%. However, when the amount of yttrium addition exceeds 1.0 at%, the hot workability deteriorates significantly. In contrast, remarkable improvement in the high temperature oxidation resistance due to the yttrium addition is demonstrated. The total thickness of the oxide layers is substantially thinner in the Y-added specimen. In particular, the thickness of (Ti,Hf) oxide layer is reduced from 200 µm to 120 µm by the addition of 0.3 at% Y.
Workability enhancement of geopolymer concrete through the use of retarder
NASA Astrophysics Data System (ADS)
Umniati, B. Sri; Risdanareni, Puput; Zein, Fahmi Tarmizi Zulfikar
2017-09-01
Geopolymer concrete is a type of concrete manufactured without the addition of cement. In geopolymer concrete, along with an activator, cement as the concrete binder can be replaced by the fly ash. This will reduce global demand on cement, and therefore will reduce CO2 emission due to cement production. Thus, geopolymer concrete is commonly known as an eco-friendly concrete. Geopolymer concrete also offers a solution concerning with the utilization of the fly ash waste. However, despite of its environmental advantages, geopolymer concrete has a drawback, namelygeopolymer concrete set quickly, thus reducing its workability. This research aimed to increase the workability of geopolymer concrete by using retarder admixture (Plastocrete RT6 Plus). Retarder used varies within 0.2%, 0.4% and 0.6% of fly ash mass. As a control, geopolymer concrete without retarder (0%) were also made. Activator used in this research was Na2SiO3 mixed with NaOH 10 M solution, with ratio of 1:5. The results showed an optimum composition of geopolymer concrete with 0.6% retarder, where initial setting time occured after 6.75 hours, and the final setting time reached after 9.5 hours. Moreover, the slump of the geopolymer concrete was 8.8 cm, and the slump flow was 24 cm. The compressive strength of the geopolymer concrete at 28 days was 47.21 MPa. The experiment showed that the more retarder added, the setting time of the geopolymer concrete will be increased, thus increasing its workability.
NASA Technical Reports Server (NTRS)
Gamwell, W. R.; McGill, P. B.
2006-01-01
Aluminum-Beryllium metal matrix composite materials are useful due to their desirable performance characteristics for aerospace applications. Desirable characteristics of this material includes light-weight, dimensional stability, stiffness, good vibration damping characteristics, low coefficient of thermal expansion, and workability, This material is 3.5 times stiffer and 22% lighter than conventional aluminum alloys. electro-optical systems, advanced sensor and guidance components for flight and satellite systems, components for light-weight high-performance aircraft engines, and structural components for helicopters. Aluminum-beryllium materials are now available in the form of near net shape investment castings. In this materials properties characterization study, the cryogenic tensile and fracture properties of an investment casting alloy, Beralcast 363, were determined. Tensile testing was performed at 21 C (70 F), -73.3 C (-100 F), -195.5 C (-320 F) and -252.8 C (-423 F), and fracture (K(sub lc) and da/dN) testing was performed at -73.3 C (-100 F), -195.5 C (-320 F) and -252.8 C (-423 F). Their use is attractive for weight critical structural applications such as advanced
NASA Technical Reports Server (NTRS)
Thacher, E. F.
1972-01-01
Six subscale Intermold cylinder assemblies with a total of twelve different concepts for transition to AGCarb were fabricated. Three of the cylinder assemblies were made by helically winding the hoop fibers and three were of orthogonal configuration. The fabrication process is summarized and details of each manufacturing method are given. The objectives of the test program were to: (1) demonstrate the fabricability of the Intermold 3 subscale flanges, (2) produce an integral transition from Intermold 3 to AGCarb material, (3) define a workable manufacturing process, and (4) identify a best suited inspection method. The objectives were met and the results are described.
Ahrens, Ernst H.
1999-01-01
An ultrafine cementitious grout in three particle grades containing Portland cement, pumice as a pozzolanic material and superplasticizer in the amounts of about 30 wt. % to about 70 wt. % Portland cement; from about 30 wt. % to about 70 wt. % pumice containing at least 70% amorphous silicon dioxide; and from 1.2 wt. % to about 5.0 wt. % superplasticizer. The superplasticizer is dispersed in the mixing water prior to the addition of dry grout and the W/CM ratio is about 0.4 to 1/1. The grout has very high strength and very low permeability with good workability. The ultrafine particle sizes allow for sealing of microfractures below 10 .mu.m in width.
Low cost fabrication development for oxide dispersion strengthened alloy vanes
NASA Technical Reports Server (NTRS)
Perkins, R. J.; Bailey, P. G.
1978-01-01
Viable processes were developed for secondary working of oxide dispersion strengthened (ODS) alloys to near-net shapes (NNS) for aircraft turbine vanes. These processes were shown capable of producing required microstructure and properties for vane applications. Material cost savings of 40 to 50% are projected for the NNS process over the current procedures which involve machining from rectangular bar. Additional machining cost savings are projected. Of three secondary working processes evaluated, directional forging and plate bending were determined to be viable NNS processes for ODS vanes. Directional forging was deemed most applicable to high pressure turbine (HPT) vanes with their large thickness variations while plate bending was determined to be most cost effective for low pressure turbine (LPT) vanes because of their limited thickness variations. Since the F101 LPT vane was selected for study in this program, development of plate bending was carried through to establishment of a preliminary process. Preparation of ODS alloy plate for bending was found to be a straight forward process using currently available bar stock, providing that the capability for reheating between roll passes is available. Advanced ODS-NiCrAl and ODS-FeCrAl alloys were utilized on this program. Workability of all alloys was adequate for directional forging and plate bending, but only the ODS-FeCrAl had adequate workability for shaped preform extrustion.
Effect of boron waste on the properties of mortar and concrete.
Topçu, Iker Bekir; Boga, Ahmet Raif
2010-07-01
Utilization of by-products or waste materials in concrete production are important subjects for sustainable development and industrial ecology concepts. The usages as mineral admixtures or fine aggregates improve the durability properties of concrete and thus increase the economic and environmental advantages for the concrete industry. The effect of clay waste (CW) containing boron on the mechanical properties of concrete was investigated. CW was added in different proportions as cement additive in concrete. The effect of CW on workability and strength of concrete were analysed by fresh and hardened concrete tests. The results obtained were compared with control concrete properties and Turkish standard values. The results showed that the addition of CW had a small effect upon the workability of the concrete but an important effect on the reduction of its strength. It was observed that strength values were quite near to that of control concrete when not more than 10% CW was used in place of cement. In addition to concrete specimens, replacing cement with CW produced mortar specimens, which were investigated for their strength and durability properties. The tests of SO( 4) (2-) and Cl(-) effect as well as freeze-thaw behaviour related to the durability of mortar were performed. Consequently, it can be said that some improvements were obtained in durability properties even if mechanical properties had decreased with increasing CW content.
Single point incremental forming: Formability of PC sheets
NASA Astrophysics Data System (ADS)
Formisano, A.; Boccarusso, L.; Carrino, L.; Lambiase, F.; Minutolo, F. Memola Capece
2018-05-01
Recent research on Single Point Incremental Forming of polymers has slightly covered the possibility of expanding the materials capability window of this flexible forming process beyond metals, by demonstrating the workability of thermoplastic polymers at room temperature. Given the different behaviour of polymers compared to metals, different aspects need to be deepened to better understand the behaviour of these materials when incrementally formed. Thus, the aim of the work is to investigate the formability of incrementally formed polycarbonate thin sheets. To this end, an experimental investigation at room temperature was conducted involving formability tests; varying wall angle cone and pyramid frusta were manufactured by processing polycarbonate sheets with different thicknesses and using tools with different diameters, in order to draw conclusions on the formability of polymer sheets through the evaluation of the forming angles and the observation of the failure mechanisms.
Psychological well-being and workability in child abuse investigators.
Tehrani, N
2018-05-17
Working with victims and offenders of child abuse can impact on the health and well-being of police officers and staff. To identify the effects of tenure, work ability, gender and a personal experience of child abuse on symptoms of anxiety, depression and primary and secondary trauma in child abuse investigators (CAIs). Screening questionnaires were sent to police officers and staff. The officers and staff worked in child protection in seven police forces. The surveillance was undertaken online and the data were encrypted and personal identifiers removed. The four clinical measures were Goldberg Anxiety/Depression Scale, Professional Quality of Life and Impact of Events (extended). Eighty-two per cent of 2798 CAIs returned questionnaires. There was a statistically significant relationship between all four clinical symptoms and workability (P < 0.001), between tenure and primary trauma (P < 0.01) and between anxiety, depression, primary trauma and workability and adverse childhood experience (ACE) scores (P < 0.001). Regression analysis showed that workability, tenure and ACE scores explained between 12 and 23% of the variance. There were gender differences with women having higher levels of symptoms; however, the effect size and clinical significance were negligible for all but the primary trauma scores. Psychological surveillance can provide an important source of evidence for occupational health practitioners working with CAIs in informing them of the factors which could be considered in selecting, training, supporting and retaining officers and staff. Psychological surveillance can also help police management to identify ways to monitor the long-term effectiveness and well-being of CAIs.
Study on The Geopolymer Concrete Properties Reinforced with Hooked Steel Fiber
NASA Astrophysics Data System (ADS)
Abdullah, M. M. A. B.; Tahir, M. F. M.; Tajudin, M. A. F. M. A.; Ekaputri, J. J.; Bayuaji, R.; Khatim, N. A. M.
2017-11-01
In this research, Class F fly ash and a mixture of alkaline activators and different amount of hooked steel fiber were used for preparing geopolymer concrete. In order to analyses the effect of hooked steel fiber on the geopolymer concrete, the analysis such as chemical composition of fly ash, workability of fresh geopolymer, water absorption, density, compressive strength of hardened geopolymer concrete have been carried out. Mixtures were prepared with fly ash to alkaline liquid ratio of 2.0 with hooked steel fibers were added to the mix with different amounts which are 1%, 3%, 5% and 7% by the weight of the concrete. Experimental results showed that the compressive strength of geopolymer concrete increases as the hooked steel fibers increases. The optimum compressive strength obtained was up to 87.83 MPa on the 14th day. The density of geopolymer concrete are in the range between 2466 kg/m3 to 2501 kg/m3. In addition, the workability value of geopolymer without hooked steel fibers is 100 mm while the workability value of geopolymer with hooked steel fibers are between 60 mm to 30 mm.
NASA Astrophysics Data System (ADS)
Fereshteh-Saniee, Faramarz; Asgari, Mohammad; Fakhar, Naeimeh
2016-08-01
Despite valuable electrical characteristics, the use of pure aluminum in different applications has been limited due to its low strength. Non-equal channel angular pressing (NECAP) is a recently proposed severe plastic deformation process with greater induced plastic strain and, consequently, better grain refinement in the product, compared with the well-known equal channel angular pressing technique. This research is concerned with the effects of the process temperature and ram velocity on the mechanical, workability and electrical properties of AA1060 aluminum alloy. Increasing the process temperature can concurrently increase the workability, ductility and electrical conductivity, while it has a reverse influence on the strength of the NECAPed specimen, although the strengths of all the products are higher than the as-received alloy. The influence of the ram speed on the mechanical properties of the processed samples is lower than the process temperature. Finally, a compromised process condition is introduced in order to attain a good combination of workability and strength with well-preserved electrical conductivity for electrical applications of components made of pure aluminum.
A novel process for preparing fireproofing materials from various industrial wastes.
Su, Yi; Wang, Lei; Zhang, Fu-Shen
2018-05-09
In the current study, the possibility of incorporating various industrial wastes into fireproofing materials was investigated. It was found that the newly developed materials showed excellent air sealing and fireproofing performance, with air permeability coefficients 3 to 4 orders of magnitude smaller than traditional fire prevention materials. The influence of different parameters on the air permeability was investigated, and the air sealing mechanisms were clarified through microstructure analysis. In addition, the workability and mechanical properties of the fireproofing materials for practical application in coal mine were studied. The new materials derived from industrial wastes had a compact and monolithic structure, and the excellent air tightness could be attributed to the pozzolanic activity of the industrial wastes and the film-forming property of organic polymers. Among the industrial wastes examined, a special coal fly ash with high pozzolanic activity and little free calcium oxide derived the best product with air permeability coefficient, tensile strength and breaking elongation of 4.17 × 10 -8 m 2 /s, 2.14 MPa and 48.90%, respectively. This study provides an economical, environmentally friendly and promising approach for industrial wastes recycling. Copyright © 2018 Elsevier Ltd. All rights reserved.
Second-law efficiency of solar-thermal cavity receivers
NASA Technical Reports Server (NTRS)
Moynihan, P. I.
1983-01-01
Properly quantified performance of a solar-thermal cavity receiver must not only account for the energy gains and losses as dictated by the First Law of thermodynamics, but it must also account for the quality of that energy. However, energy quality can only be determined from the Second Law. An equation for the Second Law efficiency of a cavity receiver is derived from the definition of available energy, which is a thermodynamic property that measures the maximum amount of work obtainable when a system is allowed to come into unrestrained equilibrium with the surrounding environment. The fundamental concepts of the entropy and availability of radiation were explored from which a workable relationship among the reflected cone half-angle, the insolation, and the concentrator geometric characteristics was developed as part of the derivation of the Second Law efficiency. First and Second Law efficiencies were compared for data collected from two receivers that were designed for different purposes. A Second Law approach to quantifying the performance of a solar-thermal cavity receiver lends greater insight into the total performance than does the conventional First Law method.
SGC Tests for Influence of Material Composition on Compaction Characteristic of Asphalt Mixtures
Chen, Qun
2013-01-01
Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes. PMID:23818830
Okumura, Tetsu; Okanoya, Kazuo; Tani, Jun
2007-01-01
In chronic recording experiments, self-curing dental acrylic resins have been used as a mounting base of electrodes or microdialysis-probes. Since these acrylics do not bond to the bone, screws have been used as anchors. However, in small experimental animals like finches or mouse, their craniums are very fragile and can not successfully hold the anchors. In this report, we propose a new application of light-curing dental resins for mounting base of electrodes or microdialysis probes in chronic experiments. This material allows direct bonding to the cranium. Therefore, anchor screws are not required and surgical field can be reduced considerably. Past experiences show that the bonding effect maintains more than 2 months. Conventional resin's window of time when the materials are pliable and workable is a few minutes. However, the window of working time for these dental adhesives is significantly wider and adjustable. PMID:18997897
SGC tests for influence of material composition on compaction characteristic of asphalt mixtures.
Chen, Qun; Li, Yuzhi
2013-01-01
Compaction characteristic of the surface layer asphalt mixture (13-type gradation mixture) was studied using Superpave gyratory compactor (SGC) simulative compaction tests. Based on analysis of densification curve of gyratory compaction, influence rules of the contents of mineral aggregates of all sizes and asphalt on compaction characteristic of asphalt mixtures were obtained. SGC Tests show that, for the mixture with a bigger content of asphalt, its density increases faster, that there is an optimal amount of fine aggregates for optimal compaction and that an appropriate amount of mineral powder will improve workability of mixtures, but overmuch mineral powder will make mixtures dry and hard. Conclusions based on SGC tests can provide basis for how to adjust material composition for improving compaction performance of asphalt mixtures, and for the designed asphalt mixture, its compaction performance can be predicted through these conclusions, which also contributes to the choice of compaction schemes.
Theoretical study of production of unique glasses in space
NASA Technical Reports Server (NTRS)
Larsen, D. C.
1974-01-01
Analytical functional relationships describing homogeneous nucleation and crystallization in various supercooled liquids were developed. The time and temperature dependent relationships of nucleation and crystallization (intrinsic properties) are being used to relate glass forming tendency to extrinsic parameters such as cooling rate through computer simulation. Single oxide systems are being studied initially to aid in developing workable kinetic models and to indicate the primary materials parameters affecting glass formation. The theory and analytical expressions developed for simple systems is then extended to complex oxide systems. A thorough understanding of nucleation and crystallization kinetics of glass forming systems provides a priori knowledge of the ability of a given system to form a glass.
Chakraborty, Pritam; Zhang, Yongfeng; Tonks, Michael R.
2015-12-07
In this study, the fracture behavior of brittle materials is strongly influenced by their underlying microstructure that needs explicit consideration for accurate prediction of fracture properties and the associated scatter. In this work, a hierarchical multi-scale approach is pursued to model microstructure sensitive brittle fracture. A quantitative phase-field based fracture model is utilized to capture the complex crack growth behavior in the microstructure and the related parameters are calibrated from lower length scale atomistic simulations instead of engineering scale experimental data. The workability of this approach is demonstrated by performing porosity dependent intergranular fracture simulations in UO 2 and comparingmore » the predictions with experiments.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chakraborty, Pritam; Zhang, Yongfeng; Tonks, Michael R.
In this study, the fracture behavior of brittle materials is strongly influenced by their underlying microstructure that needs explicit consideration for accurate prediction of fracture properties and the associated scatter. In this work, a hierarchical multi-scale approach is pursued to model microstructure sensitive brittle fracture. A quantitative phase-field based fracture model is utilized to capture the complex crack growth behavior in the microstructure and the related parameters are calibrated from lower length scale atomistic simulations instead of engineering scale experimental data. The workability of this approach is demonstrated by performing porosity dependent intergranular fracture simulations in UO 2 and comparingmore » the predictions with experiments.« less
NASA Astrophysics Data System (ADS)
Aslaksen Aasly, Kari; Meyer, Gurli Birgitte; Kløve Keiding, Jakob; Langås, Rune; Lund, Vegard
2017-04-01
The Nidaros Cathedral situated in Trondheim, Norway is a restored cathedral resting on the remnants of an original medieval church sanctified St Olav. The cathedral became one of the most important sanctuary for pilgrimage during the Middle Ages and still is today. In a European context the cathedral, along with a certain group of other churches and monasteries in Norway, is unique by being build from soapstone (steatite). This talc and chlorite dominated metamorphic rock is relatively soft, heat resistant and dense making the material ideal for cooking pots, stoves and all kinds of utensils. Soapstone has therefore been appreciated, used and quarried since the Stone Age in Norway. At the onset of Christianity the choice of soapstone from harder rock types was not difficult for the building owners combining the vision of stone churches in Norway with the skills of wood carving traditions of local handicraftsmen. The best example is the Nidaros Cathedral built in the 11th to 14th century. In 1869, the Nidaros Cathedral Restoration Workshop (NDR) was founded with the purpose of restoring the cathedral using original craftsman's techniques and authentic materials. The restoration was originally completed in 1969, but is still ongoing due to weathering of certain used soapstone types. A major challenge remains to find soapstone resources of the right quality. Core issues relate to avoid rocks with cracks and cleavage, a demand for homogeneity, maintaining esthetic authenticity, resistance to weathering (disintegration) and last but not least the ultimatum of workability. Thus locating new soapstone resources depends strongly on geological understanding, quarry experience and stone carver's knowledge. The present work is based on close cooperation between stone carvers and geologists in a common goal of uniting knowledge and experience in defining qualities of soapstone for various purposes of restoration. Cooperate observations of geology and carving properties in the very same spots has been performed during fieldwork, through studies of drill cores and during carving in the workshop of NDR. Through careful geological translation of terms and experience from the stone carvers, a series of stone properties have been outlined. Supplementary studies of alteration and damages to stone has added significantly to the present bank of knowledge. The internal qualities of a soapstone has subsequently been described in terms of the geological processes forming it and the cycles of deformation altering it. The most important conclusion from this work is, that most deposits holds contradictions between workability and durability. The workability calls for soft minerals while the durability is dependent on weathering resistant and hard minerals. Only a narrow window exists in which the softness is united with resistance to alteration.
Visualization of Concrete Slump Flow Using the Kinect Sensor
Park, Minbeom
2018-01-01
Workability is regarded as one of the important parameters of high-performance concrete and monitoring it is essential in concrete quality management at construction sites. The conventional workability test methods are basically based on length and time measured by a ruler and a stopwatch and, as such, inevitably involves human error. In this paper, we propose a 4D slump test method based on digital measurement and data processing as a novel concrete workability test. After acquiring the dynamically changing 3D surface of fresh concrete using a 3D depth sensor during the slump flow test, the stream images are processed with the proposed 4D slump processing algorithm and the results are compressed into a single 4D slump image. This image basically represents the dynamically spreading cross-section of fresh concrete along the time axis. From the 4D slump image, it is possible to determine the slump flow diameter, slump flow time, and slump height at any location simultaneously. The proposed 4D slump test will be able to activate research related to concrete flow simulation and concrete rheology by providing spatiotemporal measurement data of concrete flow. PMID:29510510
The Effect of Graphene Oxide on Cement Mortar
NASA Astrophysics Data System (ADS)
Kjaernsmo, Henrik; Kakay, Samdar; Fossa, Kjell T.; Gronli, John
2018-05-01
This paper investigates the effect of water dispersed- and powder Graphene oxide (GO) nanoparticle on fresh cement mortar, microstructure and mechanical strength after 3,7, and 28 days of curing. These properties were studied by treating the cement mortar with 0.03 wt%, 0.05 wt%, and 0.2 wt% GO of the cement weight combined with 0.8wt % polycarboxylate superplasticizer. The results show that the workability decreases as increasing the content of water dispersed GO. The heat of hydration is increased for both types of GO systems. The percent air content in 0.03 wt% and 0.05 wt% GO is almost constant, but increased from 3.2 % to 4.9 % in 0.2 wt% water dispersed GO. The increased air content has effect on poor compaction and workability. GO has the potential of accelerating the hydration process and enhance the early mechanical strength (3 and 7 days), but the workability seems to diminish the mechanical strength after 28 days of curing, particularly for the highest content of water dispersed GO. No distinct influence of GO on the microstructure. The overall results showed that the impact of water dispersed GO was found out to be higher than the powder GO.
Visualization of Concrete Slump Flow Using the Kinect Sensor.
Kim, Jung-Hoon; Park, Minbeom
2018-03-03
Workability is regarded as one of the important parameters of high-performance concrete and monitoring it is essential in concrete quality management at construction sites. The conventional workability test methods are basically based on length and time measured by a ruler and a stopwatch and, as such, inevitably involves human error. In this paper, we propose a 4D slump test method based on digital measurement and data processing as a novel concrete workability test. After acquiring the dynamically changing 3D surface of fresh concrete using a 3D depth sensor during the slump flow test, the stream images are processed with the proposed 4D slump processing algorithm and the results are compressed into a single 4D slump image. This image basically represents the dynamically spreading cross-section of fresh concrete along the time axis. From the 4D slump image, it is possible to determine the slump flow diameter, slump flow time, and slump height at any location simultaneously. The proposed 4D slump test will be able to activate research related to concrete flow simulation and concrete rheology by providing spatiotemporal measurement data of concrete flow.
Pilegis, Martins; Gardner, Diane; Lark, Robert
2016-06-02
Manufactured sand differs from natural sea and river dredged sand in its physical and mineralogical properties. These can be both beneficial and detrimental to the fresh and hardened properties of concrete. This paper presents the results of a laboratory study in which manufactured sand produced in an industry sized crushing plant was characterised with respect to its physical and mineralogical properties. The influence of these characteristics on concrete workability and strength, when manufactured sand completely replaced natural sand in concrete, was investigated and modelled using artificial neural networks (ANN). The results show that the manufactured sand concrete made in this study generally requires a higher water/cement (w/c) ratio for workability equal to that of natural sand concrete due to the higher angularity of the manufactured sand particles. Water reducing admixtures can be used to compensate for this if the manufactured sand does not contain clay particles. At the same w/c ratio, the compressive and flexural strength of manufactured sand concrete exceeds that of natural sand concrete. ANN proved a valuable and reliable method of predicting concrete strength and workability based on the properties of the fine aggregate (FA) and the concrete mix composition.
Pilegis, Martins; Gardner, Diane; Lark, Robert
2016-01-01
Manufactured sand differs from natural sea and river dredged sand in its physical and mineralogical properties. These can be both beneficial and detrimental to the fresh and hardened properties of concrete. This paper presents the results of a laboratory study in which manufactured sand produced in an industry sized crushing plant was characterised with respect to its physical and mineralogical properties. The influence of these characteristics on concrete workability and strength, when manufactured sand completely replaced natural sand in concrete, was investigated and modelled using artificial neural networks (ANN). The results show that the manufactured sand concrete made in this study generally requires a higher water/cement (w/c) ratio for workability equal to that of natural sand concrete due to the higher angularity of the manufactured sand particles. Water reducing admixtures can be used to compensate for this if the manufactured sand does not contain clay particles. At the same w/c ratio, the compressive and flexural strength of manufactured sand concrete exceeds that of natural sand concrete. ANN proved a valuable and reliable method of predicting concrete strength and workability based on the properties of the fine aggregate (FA) and the concrete mix composition. PMID:28773560
Baiguini, Alessandro; Colletta, Stefano; Rebella, Valentina
2011-01-01
For some time, packaging materials and articles intended to come into contact with food are included in the system of controls, early warnings and risk communication provided by the European Commission (EU) regulation 178/2002. Data analysis of the EU rapid alert system for food allows one to define a specific risk profile and to establish an effective plan for official control of materials intended to come into contact with food. In the 2008-2010 period the rapid alert system has ratified alert notifications, mostly related to plastic materials of Chinese origin.
How to pitch a brilliant idea.
Elsbach, Kimberly D
2003-09-01
Coming up with creative ideas is easy; selling them to strangers is hard. Entrepreneurs, sales executives, and marketing managers often go to great lengths to demonstrate how their new concepts are practical and profitable--only to be rejected by corporate decision makers who don't seem to understand the value of the ideas. Why does this happen? Having studied Hollywood executives who assess screenplay pitches, the author says the person on the receiving end--the "catcher"--tends to gauge the pitcher's creativity as well as the proposal itself. An impression of the pitcher's ability to come up with workable ideas can quickly and permanently overshadow the catcher's feelings about an idea's worth. To determine whether these observations apply to business settings beyond Hollywood, the author attended product design, marketing, and venture-capital pitch sessions and conducted interviews with executives responsible for judging new ideas. The results in those environments were similar to her observations in Hollywood, she says. Catchers subconsciously categorize successful pitchers as showrunners (smooth and professional), artists (quirky and unpolished), or neophytes (inexperienced and naive). The research also reveals that catchers tend to respond well when they believe they are participating in an idea's development. As Oscar-winning writer, director, and producer Oliver Stone puts it, screen-writers pitching an idea should "pull back and project what he needs onto your idea in order to make the story whole for him." To become a successful pitcher, portray yourself as one of the three creative types and engage your catchers in the creative process. By finding ways to give your catchers a chance to shine, you sell yourself as a likable collaborator.
The role of material engineering within the concept of an integrated water resources management
NASA Astrophysics Data System (ADS)
Breiner, Raphael; Müller, Harald S.
2016-09-01
By means of a case study, the successful implementation of a rheologically optimised cement-based mortar for the construction as well as for the rehabilitation of rain water cisterns is presented in this paper. The material was developed within the scope of a German-Indonesian joint project ["Integrated Water Resources Management" (IWRM)], funded by the German Federal Ministry of Education and Research. Comprehensive rheological investigations are presented which provide the database for the optimization of the mortar with regard to its intended range of application. For the selection of the source materials, special emphasis was placed on the ready availability at low cost. The rheological properties of the fresh mortar allow an easy workability by hand while the hardened mortar shows a durable and tight appearance at the same time. The developed material can be used as a coating for walls, floors and ceilings of cisterns, for the local rehabilitation of damaged areas only or even as a construction material for complete new cisterns. The future multiplication of the IWRM project results within the region was assured by a local capacity development when the presented material concept was applied in practise in Indonesia for the construction of sustainable rain water cisterns in Gunung Kidul.
NASA Astrophysics Data System (ADS)
Ananthkumar, M.; Sathyan, Dhanya; Prabha, B.
2018-02-01
The cost of construction materials is increasing day by day because of high demand, scarcity of raw materials and high price of energy. From the view point of energy saving and over consumption of resources, the use of alternative constituents in construction materials is now a global concern. From this, the extensive research and development works towards exploring new ingredients are required for producing sustainable and environment friendly construction materials. Bagasse pulp liquor is one such material that can be used as a chemical admixture which is obtained as a by-product of paper manufacturing process. Around 5 million tons of bagasse pulp is obtained throughout the world each year. since the material is a waste product from paper industry, this can be changed as a admixture by its effective use in concrete. In the present investigation black pulp liquor is added to fresh concrete in different dosages, the concrete is then tested for workability, compressive strength, flexural, split tensile strength and setting time. From results it is shown that 1% replacement of water with black pulp liquor increases the fresh properties of the concrete, 2% replacement of water with black pulp liquor increases the mechanical properties of the concrete and acts as a set retarder.
Superplasticizer Addition to Carbon Fly Ash Geopolymers Activated at Room Temperature.
Carabba, Lorenza; Manzi, Stefania; Bignozzi, Maria Chiara
2016-07-18
Present concerns about global warming due to the greenhouse emissions in the atmosphere have pushed the cement industry to research alternatives to ordinary Portland cement (OPC). Geopolymer binder may constitute a possible breakthrough in the development of sustainable materials: understanding the effectiveness and the influences of superplasticizers on geopolymer systems is one of the essential requirements for its large-scale implementation. This study aims to investigate the possibility of using commercially available chemical admixtures designed for OPC concrete, to improve fresh properties of fly ash-based geopolymers and mortars. A special emphasis is laid upon evaluating their influence on mechanical and microstructural characteristics of the hardened material realized under room-temperature curing conditions. Results indicate that the addition of a polycarboxylic ether-based superplasticizer, in the amount of 1.0 wt. % by mass of fly ash, promotes an improvement in workability without compromising the final strength of the hardened material. Moreover, the addition of the polycarboxylic ether- and acrylic-based superplasticizers induces a refinement in the pore structure of hardened mortar leading to a longer water saturation time.
Superplasticizer Addition to Carbon Fly Ash Geopolymers Activated at Room Temperature
Carabba, Lorenza; Manzi, Stefania; Bignozzi, Maria Chiara
2016-01-01
Present concerns about global warming due to the greenhouse emissions in the atmosphere have pushed the cement industry to research alternatives to ordinary Portland cement (OPC). Geopolymer binder may constitute a possible breakthrough in the development of sustainable materials: understanding the effectiveness and the influences of superplasticizers on geopolymer systems is one of the essential requirements for its large-scale implementation. This study aims to investigate the possibility of using commercially available chemical admixtures designed for OPC concrete, to improve fresh properties of fly ash-based geopolymers and mortars. A special emphasis is laid upon evaluating their influence on mechanical and microstructural characteristics of the hardened material realized under room-temperature curing conditions. Results indicate that the addition of a polycarboxylic ether-based superplasticizer, in the amount of 1.0 wt. % by mass of fly ash, promotes an improvement in workability without compromising the final strength of the hardened material. Moreover, the addition of the polycarboxylic ether- and acrylic-based superplasticizers induces a refinement in the pore structure of hardened mortar leading to a longer water saturation time. PMID:28773707
NASA Astrophysics Data System (ADS)
Landrou, Gnanli; Brumaud, Coralie; Habert, Guillaume
2017-06-01
In the ceramic industry and in many sectors, clay minerals are widely used. In earthen construction technique, clay plays a crucial role in the processing. The purpose of this research is to understand and modify the clay properties in earth material to propose an innovative strategy to develop a castable earth-based material. To do so, we focused on the modification of clay properties at fresh state with inorganic additives. As the rheological behaviour of clays is controlled by their surface charge, the addition of phosphate anion allows discussing deep the rheology of concentrated clay suspensions. We highlighted the thixotropic and shear thickening behaviour of a dispersed kaolinite clay suspensions. Indeed, by adding sodium hexametaphosphate the workability of clay paste increases and the behaviour is stable during time after a certain shear is applied. Moreover, we stress that the aging and the shift in critical strain in clay system are due to the re-arrangement of clay suspension and a decrease of deformation during time. The understanding of both effect: thixotropy and aging are crucial for better processing of clay-based material and for self-compacting clay concrete. Yet, studies need to pursue to better understand the mechanism.
NASA Astrophysics Data System (ADS)
Krasikov, E.; Nikolaenko, V.
2017-01-01
Fast neutron intensity influence on reactor materials radiation damage is a critically important question in the problem of the correct use of the accelerated irradiation tests data for substantiation of the materials workability in real irradiation conditions that is low neutron intensity. Investigations of the fast neutron intensity (flux) influence on radiation damage and experimental data scattering reveal the existence of non-monotonous sections in kinetics of the reactor pressure vessels (RPV) steel damage. Discovery of the oscillations as indicator of the self-organization processes presence give reasons for new ways searching on reactor pressure vessel (RPV) steel radiation stability increasing and attempt of the self-restoring metal elaboration. Revealing of the wavelike process in the form of non monotonous parts of the kinetics of radiation embrittlement testifies that periodic transformation of the structure take place. This fact actualizes the problem of more precise definition of the RPV materials radiation embrittlement mechanisms and gives reasons for search of the ways to manage the radiation stability (nanostructuring and so on to stimulate the radiation defects annihilation), development of the means for creating of more stableness self recovering smart materials.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Cindy Xiaohui; Lim, Chao Voon; Castagne, Sylvie
Titanium and its alloys have a wide range of applications in various industries such as aerospace, medical, automotive and even commercial products. However, formability of titanium alloys has always been an issue. This study presents the results of an investigation on the workability and response of Ti-6Al-4V deformed at different strain rates and lower elevated temperatures with different initial microstructures. Compression tests of cylindrical specimens were performed at various temperatures (300 deg. C, 400 deg. C, 450 deg. C, 500 deg. C) and at different strain rates (0.001 s{sup -1}, 0.02 s{sup -1} and 0.1 s{sup -1}). The effects ofmore » strain rate, temperature and initial microstructure on the workability of the Ti alloy were investigated. Based on these experimental results, workability maps for the respective initial microstructures were developed. Results showed that temperature played an important role in the formability of Ti-6Al-4V titanium alloys unlike strain rate. In addition, feasibility study on Multi-Directional Forging (MDF) was performed and positive results were obtained. It was demonstrated that Ti-6Al-4V titanium alloys can undergo severe plastic deformation at lower elevated temperature (400-500 deg. C) and at a higher strain rate of 0.1 s{sup -1}.« less
Life Cycle Assessment of Completely Recyclable Concrete.
De Schepper, Mieke; Van den Heede, Philip; Van Driessche, Isabel; De Belie, Nele
2014-08-21
Since the construction sector uses 50% of the Earth's raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW) is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC) is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C) principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA) needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete.
Use of selected waste materials in concrete mixes.
Batayneh, Malek; Marie, Iqbal; Asi, Ibrahim
2007-01-01
A modern lifestyle, alongside the advancement of technology has led to an increase in the amount and type of waste being generated, leading to a waste disposal crisis. This study tackles the problem of the waste that is generated from construction fields, such as demolished concrete, glass, and plastic. In order to dispose of or at least reduce the accumulation of certain kinds of waste, it has been suggested to reuse some of these waste materials to substitute a percentage of the primary materials used in the ordinary portland cement concrete (OPC). The waste materials considered to be recycled in this study consist of glass, plastics, and demolished concrete. Such recycling not only helps conserve natural resources, but also helps solve a growing waste disposal crisis. Ground plastics and glass were used to replace up to 20% of fine aggregates in concrete mixes, while crushed concrete was used to replace up to 20% of coarse aggregates. To evaluate these replacements on the properties of the OPC mixes, a number of laboratory tests were carried out. These tests included workability, unit weight, compressive strength, flexural strength, and indirect tensile strength (splitting). The main findings of this investigation revealed that the three types of waste materials could be reused successfully as partial substitutes for sand or coarse aggregates in concrete mixtures.
Life Cycle Assessment of Completely Recyclable Concrete
De Schepper, Mieke; Van den Heede, Philip; Van Driessche, Isabel; De Belie, Nele
2014-01-01
Since the construction sector uses 50% of the Earth’s raw materials and produces 50% of its waste, the development of more durable and sustainable building materials is crucial. Today, Construction and Demolition Waste (CDW) is mainly used in low level applications, namely as unbound material for foundations, e.g., in road construction. Mineral demolition waste can be recycled as crushed aggregates for concrete, but these reduce the compressive strength and affect the workability due to higher values of water absorption. To advance the use of concrete rubble, Completely Recyclable Concrete (CRC) is designed for reincarnation within the cement production, following the Cradle-to-Cradle (C2C) principle. By the design, CRC becomes a resource for cement production because the chemical composition of CRC will be similar to that of cement raw materials. If CRC is used on a regular basis, a closed concrete-cement-concrete material cycle will arise, which is completely different from the current life cycle of traditional concrete. Within the research towards this CRC it is important to quantify the benefit for the environment and Life Cycle Assessment (LCA) needs to be performed, of which the results are presented in a this paper. It was observed that CRC could significantly reduce the global warming potential of concrete. PMID:28788174
Katabira, Kenichi; Yoshida, Yu; Masuda, Atsuji; Watanabe, Akihito; Narita, Fumio
2018-01-01
The inverse magnetostrictive effect is an effective property for energy harvesting; the material needs to have large magnetostriction and ease of mass production. Fe–Co alloys being magnetostrictive materials have favorable characteristics which are high strength, ductility, and excellent workability, allowing easy fabrication of Fe–Co alloy fibers. In this study, we fabricated magnetostrictive polymer composites, in which Fe–Co fibers were woven into polyester fabric, and discussed their sensor performance. Compression and bending tests were carried out to measure the magnetic flux density change, and the effects of magnetization, bias magnetic field, and the location of the fibers on the performance were discussed. It was shown that magnetic flux density change due to compression and bending is related to the magnetization of the Fe–Co fiber and the bias magnetic field. The magnetic flux density change of Fe–Co fiber reinforced plastics was larger than that of the plastics with Terfenol-D particles. PMID:29522455
Konował, Emilia; Sybis, Marta; Modrzejewska-Sikorska, Anna; Milczarek, Grzegorz
2017-11-01
Various commercial dextrins were used as reducing and stabilizing agents for a novel one-step synthesis of silver nanoparticles from ammonia complexes of silver ions. As a result, stable colloids of silver were formed during the reaction with the particle size being the function of the dextrin type. The obtained colloids were characterized by UV-vis spectrophotometry, size distribution (using Non-Invasive Backscatter optics) and transmission electron microscopy (TEM). The achieved results clearly indicate the possibility of low-cost production of large quantities of colloidal silver nanoparticles using materials derived from renewable sources. The resulting silver colloids can be used for different purposes, e.g. as bactericidal agents. Combination of the aforementioned properties of nanosilver particles with plasticizing properties of dextrin enables to obtain cement mortars with increased workability and enhanced compressive strength. Moreover, the obtained material is also characterized by increased immunity to adverse impact of microorganisms. Copyright © 2017 Elsevier B.V. All rights reserved.
Di Maria, Francesco; Bianconi, Francesco; Micale, Caterina; Baglioni, Stefano; Marionni, Moreno
2016-02-01
The size distribution of aggregates has direct and important effects on fundamental properties of construction materials such as workability, strength and durability. The size distribution of aggregates from construction and demolition waste (C&D) is one of the parameters which determine the degree of recyclability and therefore the quality of such materials. Unfortunately, standard methods like sieving or laser diffraction can be either very time consuming (sieving) or possible only in laboratory conditions (laser diffraction). As an alternative we propose and evaluate the use of image analysis to estimate the size distribution of aggregates from C&D in a fast yet accurate manner. The effectiveness of the procedure was tested on aggregates generated by an existing C&D mechanical treatment plant. Experimental comparison with manual sieving showed agreement in the range 81-85%. The proposed technique demonstrated potential for being used on on-line systems within mechanical treatment plants of C&D. Copyright © 2015 Elsevier Ltd. All rights reserved.
Goddard Space Flight Center's Structural Dynamics Data Acquisition System
NASA Technical Reports Server (NTRS)
McLeod, Christopher
2004-01-01
Turnkey Commercial Off The Shelf (COTS) data acquisition systems typically perform well and meet most of the objectives of the manufacturer. The problem is that they seldom meet most of the objectives of the end user. The analysis software, if any, is unlikely to be tailored to the end users specific application; and there is seldom the chance of incorporating preferred algorithms to solve unique problems. Purchasing a customized system allows the end user to get a system tailored to the actual application, but the cost can be prohibitive. Once the system has been accepted, future changes come with a cost and response time that's often not workable. When it came time to replace the primary digital data acquisition system used in the Goddard Space Flight Center's Structural Dynamics Test Section, the decision was made to use a combination of COTS hardware and in-house developed software. The COTS hardware used is the DataMAX II Instrumentation Recorder built by R.C. Electronics Inc. and a desktop Pentium 4 computer system. The in-house software was developed using MATLAB from The MathWorks. This paper will describe the design and development of the new data acquisition and analysis system.
Haring, Catharina M; van der Meer, Jos W M; Postma, Cornelis T
2013-09-01
Performance of a focused physical examination will induce a high cognitive load for medical students in the early phase of the clinical clerkships. To come to a workable and clinically applicable standard physical examination for medical students to be used in every new patient in the daily clinical practice of internal medicine. A questionnaire held among physicians that supervise students during the clerkship of internal medicine in one Dutch training region. Of the complete list of physical examination 55 items were considered to be an integral part of the standard general physical examination for medical students. Most emphasized were elements of the physical examination aimed at general parameters, thorax and abdomen, vascular status, lymph nodes, spinal column, skin and some parts of the neurological examination. The standard physical examinations performed by supervisors themselves contain fewer items than they expected from the students. The expectations a supervisor has towards the student correlates with the frequency with which they apply the various components in their own physical examination. This study provides us with a 'core' physical examination for medical students that can be applied in the early phase of the clinical clerkships.
Goddard Space Flight Center's Structural Dynamics Data Acquisition System
NASA Technical Reports Server (NTRS)
McLeod, Christopher
2004-01-01
Turnkey Commercial Off The Shelf (COTS) data acquisition systems typically perform well and meet most of the objectives of the manufacturer. The problem is that they seldom meet most of the objectives of the end user. The analysis software, if any, is unlikely to be tailored to the end users specific application; and there is seldom the chance of incorporating preferred algorithms to solve unique problems. Purchasing a customized system allows the end user to get a system tailored to the actual application, but the cost can be prohibitive. Once the system has been accepted, future changes come with a cost and response time that's often not workable. When it came time to replace the primary digital data acquisition system used in the Goddard Space Flight Center's Structural Dynamics Test Section, the decision was made to use a combination of COTS hardware and in-house developed software. The COTS hardware used is the DataMAX II Instrumentation Recorder built by R.C. Electronics Inc. and a desktop Pentium 4 computer system. The in-house software was developed using MATLAF3 from The Mathworks. This paper will describe the design and development of the new data acquisition and analysis system.
Studies of thermochemical water-splitting cycles
NASA Technical Reports Server (NTRS)
Remick, R. J.; Foh, S. E.
1980-01-01
Higher temperatures and more isothermal heat profiles of solar heat sources are developed. The metal oxide metal sulfate class of cycles were suited for solar heat sources. Electrochemical oxidation of SO2 and thermochemical reactions are presented. Electrolytic oxidation of sulfur dioxide in dilute sulfuric acid solutions were appropriate for metal oxide metal sulfate cycles. The cell voltage at workable current densities required for the oxidation of SO2 was critical to the efficient operation of any metal oxide metal sulfate cycle. A sulfur dioxide depolarized electrolysis cell for the splitting of water via optimization of the anode reaction is discussed. Sulfuric acid concentrations of 30 to 35 weight percent are preferred. Platinized platinum or smooth platinum gave the best anode kinetics at a given potential of the five materials examined.
Pedraz, Jose Luis; Igartua, Manoli; Maria, Rosa; Hernando, Sara
2018-05-09
Nanomedicine is a field of science that employs materials in the nanometer scale. Specifically, the use of nanoparticles (NPs) has some medical applications due to their structure, for example, the ability to cross the biological barriers, and their effectiveness avoiding some drug delivery problems. Because of that, in the last years, the use of NPs has been raised as a workable solution for neurodegenerative diseases (ND) treatment [1,2]. NDs are characterized by a continuous structural and functional neuronal loss, usually correlated with neuronal death. Between NDs, Alzheimer disease (AD) and Parkinson's disease (PD) are the most common disorders worldwide, becoming a serious economic burden and public health problem [3]. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Comparing the use of sewage sludge ash and glass powder in cement mortars.
Chen, Zhen; Poon, Chi Sun
2017-06-01
This study explored the suitability of using sewage sludge ash (SSA) and mixed-colored glass powder (MGP) as construction materials in cement mortars. Positive findings from this study may help promote the recycling of waste SSA and MGP in construction works. The results indicated that the SSA decreased while MGP improved the mortar workability. The SSA exhibited very low pozzolanic activity, but the cement mortar prepared with 20% SSA yielded strength values slightly superior to those of the glass mortars due to its water absorption ability. MGP can serve as a pozzolan and when 20% of cement was replaced by MGP, apparent compressive strength gains were found at later curing ages. The SSA could be used to mitigate ASR expansion while the MGP was superior in resisting drying shrinkage.
Use of steel slag as a new material for roads
NASA Astrophysics Data System (ADS)
Ochoa Díaz, R.; Romero Farfán, M.; Cardenas, J.; Forero, J.
2017-12-01
This research paper aims to analyse the behaviour of MDC-19 hot dense asphalt mixtures with steel slag as coarse aggregate, by using asphalt 80-100, in order to verify if this residue has suitable characteristics that allow its use. The physical and mechanical characterization was accomplished using phosphorous slag from the company Acerías Paz del Río S.A. The working formula was then determined for each mixture using the RAMCODES methodology, the briquettes were produced in the laboratory and then, the design verification was performed. Taking into account the results obtained, it is concluded that the use of phosphorous slag as coarse aggregate in asphalt mixtures is workable, since acceptable design parameters and verification are obtained that meet the specifications for use as a rolling layer.
Digital image transformation and rectification of spacecraft and radar images
Wu, S.S.C.
1985-01-01
Digital image transformation and rectification can be described in three categories: (1) digital rectification of spacecraft pictures on workable stereoplotters; (2) digital correction of radar image geometry; and (3) digital reconstruction of shaded relief maps and perspective views including stereograms. Digital rectification can make high-oblique pictures workable on stereoplotters that would otherwise not accommodate such extreme tilt angles. It also enables panoramic line-scan geometry to be used to compile contour maps with photogrammetric plotters. Rectifications were digitally processed on both Viking Orbiter and Lander pictures of Mars as well as radar images taken by various radar systems. By merging digital terrain data with image data, perspective and three-dimensional views of Olympus Mons and Tithonium Chasma, also of Mars, are reconstructed through digital image processing. ?? 1985.
NASA Astrophysics Data System (ADS)
Ahmed, Ahmed S. F.; Raghavan, Vijaya
2018-01-01
Amendment of soil with biochar has been shown to enhance fertility and increase crop productivity, but the specific influence of biochar on soil workability remains unclear. Select physico-mechanical and chemical properties of clay loam and sandy loam soils were measured after amendment with wood-derived biochar of two particle size ranges (0.5-425 and 425-850 µm) at five dosages ranging from 0.5 to 10% dry weight. Whereas the clay loam soil workability decreased when the finer wood-derived biochar was applied at rates of 6 or 10%, soil fertility was not enhanced. The sandy loam soil, due to Proctor compaction, significantly decreased in bulk density with 6 and 10% wood-derived biochar amendments indicating higher soil resistance to compaction.
NASA Astrophysics Data System (ADS)
Ismail, Isham; Shahidan, Shahiron; Bahari, Nur Amira Afiza Saiful
2017-12-01
Self-compacting concrete (SCC) mixtures are usually designed to have high workability during the fresh state through the influence of higher volumes of paste in concrete mixtures. Asphalt dust waste (ADW) is one of disposed materials obtained during the production of asphalt premix. These fine powder wastes contribute to environmental problems today. However, these waste materials can be utilized in the development of sustainable and economical SCC. This paper focuses on the preliminary evaluations of the fresh properties and compressive strength of developed SCC for 7 and 28 days only. 144 cube samples from 24 mixtures with varying water binder ratios (0.2, 0.3 and 0.4) and ADW volume (0% to 100%) were prepared. MD940 and MD950 showed a satisfactory performance for the slump flow, J-Ring, L-Box and V-Funnel tests at fresh state. The compressive strength after 28 days for MD940 and MD950 was 36.9 MPa and 28.0 MPa respectively. In conclusion, the use of ADW as paste volume should be limited and a higher water binder ratio will significantly reduce the compressive strength.
NASA Astrophysics Data System (ADS)
2015-12-01
A new climate agreement won't solve climate change, but it should nudge the world onto a lower-emissions path. Research must drive deeper transformations by translating proposed solutions into workable action.
Video and Second Language Learning. Special Issue.
ERIC Educational Resources Information Center
Gillespie, Junetta B., Ed.
1985-01-01
The extent to which video has come of age with respect to language learning is the focus of this special issue, which provides information on sources of materials and offers practical ideas for the effective and creative use of those materials in second language instruction. Articles include: "Video and Language Learning: A Medium Comes of Age"…
40 CFR 419.11 - Specialized definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) The term runoff shall mean the flow of storm water resulting from precipitation coming into contact... come into direct contact with any raw material, intermediate, or finished product. (f) The following... barrel is equivalent to 42 gallons). (g) The term contaminated runoff shall mean runoff which comes into...
A Theoretical Study of Microwave Beam Absorption by a Rectenna
NASA Technical Reports Server (NTRS)
Ott, J. H.; Rice, J. S.; Thorn, D. C.
1981-01-01
The theoretical operational parameters for the workable satellite power system were examined. The system requirements for efficient transmission and reception of an environmentally benign microwave beam were determined.
NASA Astrophysics Data System (ADS)
Rostock, Roseanne
The challenge of attracting and retaining the next generation of teachers who are skilled and committed to meeting the growing demands of the profession is of increasing concern to researchers and policy makers, particularly since 45--50% of beginning teachers leave the profession within five years (Ingersoll & Smith, 2003). Reasons for such attrition include compensation, status and working conditions; however, there is growing evidence that a critical factor in new teacher retention hinges on teachers' ability to accomplish the difficult task of forming a workable professional identity in the midst of competing discourses about teaching (Alsup, 2006; Britzman, 2003). There is little research on professional identity development among those beginning teachers at highest risk for attrition (secondary math and science teachers, and those with strong academic backgrounds). This study explores the professional identity development of early-career math and science teachers who are part of the Knowles Science Teaching Foundation's (KSTF) teaching fellowship program, an external support network that aims to address many of the issues leading to high attrition among this particular population of teachers. Using narrative research methods, I examine three case studies of beginning teachers, exploring how they construct professional identity in relation to various discourse communities and negotiate tensions across multiple discourses. The cases identify both dominant discourses and counter-discourses that the teachers draw upon for important identity development resources. They also demonstrate that the way a teacher manages tensions across competing discourses is important to how well one can negotiate a workable professional identity. In particular, they emphasize the importance of engaging in borderland discourses (Gee, 1996) as a way of taking agency in one's own identity development as well as in transforming one's discourse communities. These cases shed light on how these beginning teachers work to negotiate a workable professional identity that may sustain them in a teaching career. In addition, they help us understand how a support network like KSTF can serve as a resource for helping new teachers construct professional identities, therefore addressing some of the issues that may lead to attrition among this population of new teachers.
NASA Astrophysics Data System (ADS)
Hartono, Rachmad; Raharno, Sri; Yuwana Martawirya, Yatna; Arthaya, Bagus
2018-03-01
This paper described a methodology to monitor the availability of products in a production unit in the automotive component industry. Automotive components made are automotive components made through sheet metal working. Raw material coming into production unit in the form of pieces of plates that have a certain size. Raw materials that come stored in the warehouse. Data of raw each material in the warehouse are recorded and stored in a data base system. The material will then undergo several production processes in the production unit. When the material is taken from the warehouse, material data are also recorded and stored in a data base. The data recorded are the amount of material, material type, and date when the material is out of the warehouse. The material coming out of the warehouse is labeled with information related to the production processes that the material must pass. Material out of the warehouse is a product will be made. The products have been completed, are stored in the warehouse products. When the product is entered into the product warehouse, product data is also recorded by scanning the barcode contained on the label. By recording the condition of the product at each stage of production, we can know the availability of the product in a production unit in the form of a raw material, the product being processed and the finished product.
Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S.; Katman, Herdayati; Husain, Nadiah Md
2014-01-01
Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout. PMID:24526911
Koting, Suhana; Karim, Mohamed Rehan; Mahmud, Hilmi; Mashaan, Nuha S; Ibrahim, Mohd Rasdan; Katman, Herdayati; Husain, Nadiah Md
2014-01-01
Semi-flexible pavement surfacing is a composite pavement that utilizes the porous pavement structure of the flexible bituminous pavement, which is subsequently grouted with appropriate cementitious materials. This study aims to investigate the compressive strength, flexural strength, and workability performance of cementitious grout. The grout mixtures are designed to achieve high strength and maintain flow properties in order to allow the cement slurries to infiltrate easily through unfilled compacted skeletons. A paired-sample t-test was carried out to find out whether water/cement ratio, SP percentages, and use of silica fume influence the cementitious grout performance. The findings showed that the replacement of 5% silica fume with an adequate amount of superplasticizer and water/cement ratio was beneficial in improving the properties of the cementitious grout.
Electric Motors for Non-Cryogenic Hybrid Electric and Turboelectric Propulsion
NASA Technical Reports Server (NTRS)
Duffy, Kirsten P.
2015-01-01
NASA Glenn Research Center is investigating hybrid electric and turboelectric propulsion concepts for future aircraft to reduce fuel burn, emissions, and noise. Systems studies show that the weight and efficiency of the electric system components need to be improved for this concept to be feasible. However, advances in motor component materials such as soft magnetic materials, hard magnetic materials, conductors, thermal insulation, and structural materials are expected in the coming years, and should improve motor performance. This study investigates several motor types for a one megawatt application, and projects the motor performance benefits of new component materials that might be available in the coming decades.
Electric Motor Considerations for Non-Cryogenic Hybrid Electric and Turboelectric Propulsion
NASA Technical Reports Server (NTRS)
Duffy, Kirsten P.
2015-01-01
NASA Glenn Research Center is investigating hybrid electric and turboelectric propulsion concepts for future aircraft to reduce fuel burn, emissions, and noise. Systems studies show that the weight and efficiency of the electric system components need to be improved for this concept to be feasible. However, advances in motor component materials such as soft magnetic materials, hard magnetic materials, conductors, thermal insulation, and structural materials are expected in the coming years, and should improve motor performance. This study investigates several motor types for a one megawatt application, and projects the motor performance benefits of new component materials that might be available in the coming decades.
Military engine computational structures technology
NASA Technical Reports Server (NTRS)
Thomson, Daniel E.
1992-01-01
Integrated High Performance Turbine Engine Technology Initiative (IHPTET) goals require a strong analytical base. Effective analysis of composite materials is critical to life analysis and structural optimization. Accurate life prediction for all material systems is critical. User friendly systems are also desirable. Post processing of results is very important. The IHPTET goal is to double turbine engine propulsion capability by the year 2003. Fifty percent of the goal will come from advanced materials and structures, the other 50 percent will come from increasing performance. Computer programs are listed.
DOT National Transportation Integrated Search
1974-02-01
Our work to date has involved working with aggregate gradations to minimize the voids and with different combinations of monomers, catalysts and promoters to achieve suitable strengths and workability. At present, tests are being made to evaluate the...
Characteristics of SCC with Fly Ash and Manufactured Sand
NASA Astrophysics Data System (ADS)
Praveen Kumar, K.; Radhakrishna
2016-09-01
Self compacting concrete (SCC) of M40 grade was designed. The binder in SCC consists of OPC and fly ash in the ratio of 65:35. River sand was replaced by manufactured sand (M-sand) at replacement levels of 20,40,60,80 and 100%. An attempt was made to evaluate the workability and strength characteristics of self compacting concrete with river sand and manufactured sand as fine aggregates. For each replacement level, constant workability was maintained by varying the dosage of superplasticizer. T50 flow time, V Funnel time, V-funnel T5 time as well as compressive, split tensile and flexural strength of SCC were found at each replacement level of M-sand. They were compared to SCC with river sand. Results indicate favourable use of M-sand in preparation of Self Compacting Concrete.
Studies on use of Copper Slag as Replacement Material for River Sand in Building Constructions
NASA Astrophysics Data System (ADS)
Madheswaran, C. K.; Ambily, P. S.; Dattatreya, J. K.; Rajamane, N. P.
2014-09-01
This work focuses on the use of copper slag, as a partial replacement of sand for use in cement concrete and building construction. Cement mortar mixtures prepared with fine aggregate made up of different proportions of copper slag and sand were tested for use as masonry mortars and plastering. Three masonry wall panels of dimensions 1 × 1 m were plastered. The studies showed that although copper slag based mortar is suitable for plastering, with the increase in copper slag content, the wastage due to material rebounding from the plastered surfaces increases. It is therefore suggested that the copper slag can be used for plastering of floorings and horizontal up to 50 % by mass of the fine aggregate, and for vertical surfaces, such as, brick/block walls it can be used up to 25 %. In this study on concrete mixtures were prepared with two water cement ratios and different proportions of copper slag ranging from 0 % (for the control mix) to 100 % of fine aggregate. The Concrete mixes were evaluated for workability, density, and compressive strength.
NASA Technical Reports Server (NTRS)
Graham, C. D., Jr.; Pope, D. P.; Kulkarni, S.; Wolf, M.
1978-01-01
The hot workability of polycrystalline silicon was studied. Uniaxail stress-strain curves are given for strain rates in the range of .0001 to .1/sec and temperatures from 1100 to 1380 C. At the highest strain rates at 1380 C axial strains in excess of 20% were easily obtainable without cracking. After deformations of 36%, recrystallization was completed within 0.1 hr at 1380 C. When the recrystallization was complete, there was still a small volume fraction of unrecyrstallized material which appeared very stable and may degrade the electronic properties of the bulk materials. Texture measurements showed that the as-produced vapor deposited polycrystalline rods have a 110 fiber texture with the 110 direction parallel to the growth direction and no preferred orientation about this axis. Upon axial compression perpendicular to the growth direction, the former 110 fiber axis changed to 111 and the compression axis became 110 . Recrystallization changed the texture to 110 along the former fiber axis and to 100 along the compression axis.
Physical and rheological properties of Titanium Dioxide modified asphalt
NASA Astrophysics Data System (ADS)
Buhari, Rosnawati; Ezree Abdullah, Mohd; Khairul Ahmad, Mohd; Chong, Ai Ling; Haini, Rosli; Khatijah Abu Bakar, Siti
2018-03-01
Titanium Dioxide (TiO2) has been known as a useful photocatalytic material that is attributed to the several characteristics includes high photocatalytic activity compared with other metal oxide photocatalysts, compatible with traditional construction materials without changing any original performance. This study investigates the physical and rheological properties of modified asphalt with TiO2. Five samples of asphalt with different concentration of TiO2 were studied, namely asphalt 2%, 4%, 6% 8% and 10% TiO2. The tests includes are penetration, softening point, ductility, rotational viscosity and dynamic shear rheometer (DSR) test. From the results of this study, it is noted that addition of TiO2 has significant effect on the physical properties of asphalt. The viscosity tests revealed that asphalt 10% TiO2 has good workability among with reducing approximately 15°C compared to base asphalt. Based on the results from DSR measurements, asphalt 10% TiO2 has reduced temperature susceptibility and increase stiffness and elastic behaviour in comparison to base asphalt. As a result, TiO2 can be considered to be an additive to modify the properties of asphalt.
Alternative nuclear technologies
NASA Astrophysics Data System (ADS)
Schubert, E.
1981-10-01
The lead times required to develop a select group of nuclear fission reactor types and fuel cycles to the point of readiness for full commercialization are compared. Along with lead times, fuel material requirements and comparative costs of producing electric power were estimated. A conservative approach and consistent criteria for all systems were used in estimates of the steps required and the times involved in developing each technology. The impact of the inevitable exhaustion of the low- or reasonable-cost uranium reserves in the United States on the desirability of completing the breeder reactor program, with its favorable long-term result on fission fuel supplies, is discussed. The long times projected to bring the most advanced alternative converter reactor technologies the heavy water reactor and the high-temperature gas-cooled reactor into commercial deployment when compared to the time projected to bring the breeder reactor into equivalent status suggest that the country's best choice is to develop the breeder. The perceived diversion-proliferation problems with the uranium plutonium fuel cycle have workable solutions that can be developed which will enable the use of those materials at substantially reduced levels of diversion risk.
NASA Astrophysics Data System (ADS)
Hussein, Asma Abd Elhameed; Shafiq, Nasir; Nuruddin, Muhd Fadhil
2015-05-01
Agricultural and industrial by-products are commonly used in concrete production as cement replacement materials (CRMs) or as admixtures to enhance both fresh and hardened properties of concrete as well as to save the environment from the negative effects caused by their disposal. Sugar Cane Bagasse Ash (SCBA) is one of the promising CRMs, it is used as a partial replacement of cement for producing concrete; properties of such concrete depend on the chemical composition, fineness, and burning temperature of SCBA. Approximately 1500 Million tons of sugarcane are annually produced over all the world which leave about 40-45% bagasse after juice crushing for sugar industry giving an average annual production of about 600 Million tons of bagasse as a waste material. This paper presents some findings on the effect of SCBA on workability, compressive strength and microstructure of interfacial zone of concrete and its performance is compared to some of the established CRMs namely Densified Silica Fume, Fly Ash and Microwave Incinerated Rice Husk Ash.
Constraints on Transport and Emplacement Mechanisms of Labile Fractions in Lunar Cold Traps
NASA Technical Reports Server (NTRS)
Rickman, D.; Gertsch, L.
2014-01-01
Sustaining the scientific exploration of the Solar System will require a significant proportion of the necessary fuels and propellants, as well as other bulk commodities, to be produced from local raw materials [1]. The viability of mineral production depends on the ability to locate and characterize mineable deposits of the necessary feedstocks. This requires, among other things, a workable understanding of the mechanisms by which such deposits form, which is the subject of Economic Geology. Multiple deposition scenarios are possible for labile materials on the Moon. This paper suggests labile fractions moved diffusely through space; deposits may grow richer with depth until low porosity rock; lateral transport is likely to have occurred with the regolith, at least for short distances; crystalline ice may not exist; the constituent phases could be extremely complex. At present we can constrain the sources only mildly; once on the Moon, the transport mechanisms inherently mix and therefore obscure the origins. However, the importance of expanding our understanding of ore-forming processes on the Moon behooves us to make the attempt. Thus begins a time of new inquiry for Economic Geology.
NASA Astrophysics Data System (ADS)
Byeon, J. H.; Ahmed, F.; Ko, T. J.; lee, D. K.; Kim, J. S.
2018-03-01
As the industry develops, miniaturization and refinement of products are important issues. Precise machining is required for cutting, which is a typical method of machining a product. The factor determining the workability of the cutting process is the material of the tool. Tool materials include carbon tool steel, alloy tool steel, high-speed steel, cemented carbide, and ceramics. In the case of a carbide material, the smaller the particle size, the better the mechanical properties with higher hardness, strength and toughness. The specific heat, density, and thermal diffusivity are also changed through finer particle size of the material. In this study, finite element analysis was performed to investigate the change of heat generation and cutting power depending on the physical properties (specific heat, density, thermal diffusivity) of tool material. The thermal conductivity coefficient was obtained by measuring the thermal diffusivity, specific heat, and density of the material (180 nm) in which the particle size was finer and the particle material (0.05 μm) in the conventional size. The coefficient of thermal conductivity was calculated as 61.33 for 180nm class material and 46.13 for 0.05μm class material. As a result of finite element analysis using this value, the average temperature of exothermic heat of micronized particle material (180nm) was 532.75 °C and the temperature of existing material (0.05μm) was 572.75 °C. Cutting power was also compared but not significant. Therefore, if the thermal conductivity is increased through particle refinement, the surface power can be improved and the tool life can be prolonged by lowering the temperature generated in the tool during machining without giving a great influence to the cutting power.
Code of Federal Regulations, 2011 CFR
2011-10-01
... section provides special requirements for the materials of construction of equipment that may come into..., valves, fittings, and other items of equipment that may come in contact with the cargo liquid or vapor... of equipment that may come in contact with the cargo liquid or vapor. (Equivalent to § 151.56-1(b),(c...
Code of Federal Regulations, 2010 CFR
2010-10-01
... section provides special requirements for the materials of construction of equipment that may come into..., valves, fittings, and other items of equipment that may come in contact with the cargo liquid or vapor... of equipment that may come in contact with the cargo liquid or vapor. (Equivalent to § 151.56-1(b),(c...
Code of Federal Regulations, 2014 CFR
2014-10-01
... section provides special requirements for the materials of construction of equipment that may come into..., valves, fittings, and other items of equipment that may come in contact with the cargo liquid or vapor... of equipment that may come in contact with the cargo liquid or vapor. (Equivalent to § 151.56-1(b),(c...
Code of Federal Regulations, 2012 CFR
2012-10-01
... section provides special requirements for the materials of construction of equipment that may come into..., valves, fittings, and other items of equipment that may come in contact with the cargo liquid or vapor... of equipment that may come in contact with the cargo liquid or vapor. (Equivalent to § 151.56-1(b),(c...
Code of Federal Regulations, 2013 CFR
2013-10-01
... section provides special requirements for the materials of construction of equipment that may come into..., valves, fittings, and other items of equipment that may come in contact with the cargo liquid or vapor... of equipment that may come in contact with the cargo liquid or vapor. (Equivalent to § 151.56-1(b),(c...
Learner-Centered (LCI) vs. Teacher-Centered (TCI) Instruction: A Classroom Management Perspective
ERIC Educational Resources Information Center
Minter, Mary Kennedy
2011-01-01
Teacher education should incorporate management and leadership training with an emphasis on student audience analysis. Macro perspectives of teaching are needed for a workable approach to the management of education.
Portland-cement concrete rheology and workability : final report
DOT National Transportation Integrated Search
2012-12-10
Based on research including four best practice studies, the report proposes a framework for Metropolitan Planning Organizations (MPOs) and partners to use to integrate health into metropolitan area transportation planning. The framework addresses bot...
Management: Curse, Cure-All, or Workable Concept?
ERIC Educational Resources Information Center
Prentice, Marjorie
1973-01-01
In order for curriculum workers to plan and organize in an orderly, rational manner, an operating model is described which identifies the necessary components of the system and clearly states relationships between such components. (Author/CB)
Code of Federal Regulations, 2010 CFR
2010-01-01
... equipment, pipeline and instrumentation surfaces (that come in contact with the gas) must be made of materials that remain stable in contact with UF6. All surfaces which come into contact with the process gas... compressors or gas blowers made of or protected by materials resistant to UF6 corrosion and with a suction...
DOT National Transportation Integrated Search
2008-12-01
Warm Mix Asphalt (WMA) technology, recently developed in Europe, is gaining strong interest in the US. By : lowering the viscosity of asphalt binder and/or increasing the workability of mixture using minimal heat, WMA : technology allows the mixing, ...
Self-Consolidating Concrete for Prestressed Bridge Girders : Research Brief
DOT National Transportation Integrated Search
2017-08-01
Self-consolidating concrete (SCC) is commonly used as an alternative to conventional concrete (CC) in precast, prestressed concrete (PSC) bridge girders. The high strength, highly workable mixture can flow through dense reinforcement to fill formwork...
NASA Astrophysics Data System (ADS)
Peng, Xiaoyan; Su, Wusen; Xiao, Dan; Xu, Guofu
2018-06-01
Hot deformation behaviors of the homogenized Al-Zn-Mg-Cu alloy were studied by uniaxial compression tests carried out at 623-743 K and strain rates of 0.01-10 s-1. The constitutive equation was developed for the activation energy, and thus the activation energy map was constructed. During the hot deformation, the dominated softening mechanisms were the dynamic recovery and dynamic recrystallization, which were most likely to be driven with increasing temperature and decreasing activation energy. Based on the superposition of the activation energy map and the processing map, together with the microstructure characteristics, the optimized hot workability of the alloy was proposed at the domain (670-743 K and 0.01-0.16 s-1), where the peak efficiency was 0.39 and the activation energy range was 196-260 kJ mol-1.
Properties of concrete containing ground palm oil fuel ash as fine aggregate replacement
NASA Astrophysics Data System (ADS)
Saffuan, W. A.; Muthusamy, K.; Salleh, N. A. Mohd; Nordin, N.
2017-11-01
Environmental degradation resulting from increasing sand mining activities and disposal of palm oil fuel ash (POFA), a solid waste generated from palm oil mill needs to be resolved. Thus, the present research investigates the effect of ground palm oil fuel ash as partial fine aggregate replacement on workability, compressive and flexural strength of concrete. Five mixtures of concrete containing POFA as partial sand replacement designed with 0%, 10%, 20%, 30% and 40% of POFA by the weight of sand were used in this experimental work. The cube and beam specimens were casted and water cured up to 28 days before subjected to compressive strength and flexural strength testing respectively. Finding shows that concrete workability reduces as the amount of POFA added become larger. It is worth to note that 10% of POFA is the best amount to be used as partial fine aggregate replacement to produce concrete with enhanced strength.
NASA Astrophysics Data System (ADS)
Khed, Veerendrakumar C.; Mohammed, Bashar S.; Fadhil Nuruddin, Muhd
2018-04-01
The different sizes of crumb rubber have been used to investigate the effects on flowability and the compressive strength of the hybrid fibre reinforced engineered cementitious composite. Two sizes of crumb rubber 30 mesh and 1 to 3mm were used in partial replacement with the fine aggregate up to 60%. The experimental study was carried out through mathematical and statistical analysis by response surface methodology (RSM) using the Design Expert software. The response models have been developed and the results were validated by analysis of variance (ANOVA). It was found that finer sized crumb rubber inclusion had produced better workability and higher compressive strength when compared to the larger size and it was concluded that crumb rubber has negative effect on compressive strength and positive effect on workability. The optimization results are found to an approximately good agreement with the experimental results.
von Thiele Schwarz, Ulrica; Augustsson, Hanna; Hasson, Henna; Stenfors-Hayes, Terese
2015-02-01
To test the effects of integrating health protection and health promotion with a continuous improvement system (Kaizen) on proximal employee outcomes (health promotion, integration, and Kaizen) and distal outcomes (workability, productivity, self-rated health and self-rated sickness absence). Twelve units in a county hospital in Sweden were randomized to control or intervention groups using a quasiexperimental study design. All staff (approximately 500) provided self-ratings in questionnaires at baseline, and a 12- and 24-month follow-up (response rate, 79% to 87.5%). There was a significant increase in the proximal outcomes over time in the intervention group compared with the control group, and a trend toward improvement in the distal outcomes workability and productivity. Integration seems to promote staff engagement in health protection and promotion, as well as to improve their understanding of the link between work and health.
Evaluation of Sandwich Structure Bonding In Out-of-Autoclave Processing
NASA Technical Reports Server (NTRS)
Hou, Tan-Hung; Baughman, James M.; Zimmerman, Thomas J.; Sutter, James K.; Gardner, John M.
2010-01-01
The out-of-autoclave-vacuum-bag-only (OOA-VBO) process is low in capital expenditures compared to the traditional autoclave, however, the material challenges for OOA-VBO workable material systems are high. Presently there are few such aerospace grade prepreg materials available commercially. In this study, we evaluated processing and properties of honeycomb sandwich structure (HC/SS) panels fabricated by co-curing composite face sheet with adhesives by the OOA-VBO process in an oven. The prepreg materials were IM7/MTM 45-1 and T40-800B/5320. Adhesives studied were AF-555M, XMTA-241/PM15, FM-309-1M and FM-300K. Aluminum H/C cores with and without perforations were included. It was found that adhesives in IM7/MTM 45-1/AF-555M, T40-800B/5320/FM 309-1M and T40-800B/5320/FM-300K panels all foamed but yielded high flatwise tensile (FWT) strength values above 8,275 kPA (1,200 psi). IM7/MTM 45-1/XMTA-241/PM15 did not foam, yet yielded a low FWT strength. SEM photomicrographs revealed that the origin of this low strength was poor adhesion in the interfaces between the adhesive and face sheet composite due to poor wetting associated with the high initial viscosity of the XMTA-241/PM15 adhesive.
Performance Using Bamboo Fiber Ash Concrete as Admixture Adding Superplasticizer
NASA Astrophysics Data System (ADS)
Vasudevan, Gunalaan
2017-06-01
The increasing demand on natural resources for housing provisions in developing countries have called for sourcing and use of sustainable local materials for building and housing delivery. Natural materials to be considered sustainable for building construction should be ‘green’ and obtained from local sources, including rapidly renewable plant materials like palm fronds and bamboo, recycled materials and other products that are reusable and renewable. Each year, tens of millions of tons of bamboo are utilized commercially, generating a vast amount of waste. Besides that, bamboo fiber is easy availability, low density, low production cost and satisfactory mechanical properties. One solution is to activate this waste by using it as an additive admixture in concrete to keep it out of landfills and save money on waste disposal. The research investigates the mechanical and physical properties of bamboo fiber powder in a blended Portland cement. The structural value of the bamboo fiber powder in a blended Portland cement was evaluated with consideration for its suitability in concrete. Varied percentage of bamboo fiber powder (BFP) at 0%, 5%, 10%, 15%, and 20% as an admixture in 1:2:4 concrete mixes. The workability of the mix was determined through slump; standard consistency test was carried on the cement. Compressive strength of hardened cured (150 x 150 x 150) mm concrete cubes at 7days, 14days and 28days were tested.
The influence of silanized nano-SiO{sub 2} on the hydration of cement paste: NMR investigations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bede, A., E-mail: Andrea.Bede@phys.utcluj.ro; Pop, A.; Ardelean, I.
2015-12-23
It is known that by adding a small amount of nanoparticles to the cement-based materials a strong influence on the workability, strength and durability is obtained. These characteristics of the material are fundamentally determined by the hydration process taking place after mixing the cement grains with water. In the present study the influence introduced by the addition of nano-silica with silanized surfaces on the hydration process was investigated using low-field nuclear magnetic resonance (NMR) relaxometry. The cement samples were prepared using gray cement at a water-to-cement ratio of 0.4 and a 5% addition of nanosilica. The surface of the nanoparticlesmore » was modified using a coating of Silane A174. The cement pastes were monitored during their standard curing time of 28 days. It was established that, by using unmodified nanosilica particles, an acceleration of the hydration process takes place as compared with the pure cement paste. On the other side, by adding silanized nanoparticles, the dormancy stage significantly extends and the hydration process is slower. This slowing down process could enhance the mechanical strength of cement based materials as a result of a better compaction of the hydrated samples.« less
Influence of bottom ash of palm oil on compressive strength of concrete
NASA Astrophysics Data System (ADS)
Saputra, Andika Ade Indra; Basyaruddin, Laksono, Muhamad Hasby; Muntaha, Mohamad
2017-11-01
The technological development of concrete demands innovation regarding the alternative material as a part of the effort in improving quality and minimizing reliance on currently used raw materials such as bottom ash of palm oil. Bottom ash known as domestic waste stemming from palm oil cultivation in East Kalimantan contains silica. Like cement in texture and size, bottom ash can be mixed with concrete in which the silica in concrete could help increase the compressive strength of concrete. This research was conducted by comparing between normal concrete and concrete containing bottom ash as which the materials were apart of cement replacement. The bottom ash used in this research had to pass sieve size (#200). The composition tested in this research involved ratio between cement and bottom ash with the following percentages: 100%: 0%, 90%: 10%, 85%: 15% and 80%: 20%. Planned to be within the same amount of compressive strength (fc 25 MPa), the compressive strength of concrete was tested at the age of 7, 14, and 28 days. Research result shows that the addition of bottom ash to concrete influenced workability in concrete, but it did not significantly influence the compressive strength of concrete. Based on the result of compressive strength test, the optimal compressive strength was obtained from the mixture of 100% cement and 0% bottom ash.
Geopolymers as potential repair material in tiles conservation
NASA Astrophysics Data System (ADS)
Geraldes, Catarina F. M.; Lima, Augusta M.; Delgado-Rodrigues, José; Mimoso, João Manuel; Pereira, Sílvia R. M.
2016-03-01
The restoration materials currently used to fill gaps in historical architectural tiles (e.g. lime or organic resin pastes) usually show serious drawbacks in terms of compatibility, effectiveness or durability. The existing solutions do not fully protect Portuguese faïence tiles ( azulejos) in outdoor conditions and frequently result in further deterioration. Geopolymers can be a potential solution for tile lacunae infill, given the chemical-mineralogical similitude to the ceramic body, and also the durability and versatile range of physical properties that can be obtained through the manipulation of their formulation and curing conditions. This work presents and discusses the viability of the use of geopolymeric pastes to fill lacunae in tiles or to act as "cold" cast ceramic tile surrogates reproducing missing tile fragments. The formulation of geopolymers, namely the type of activators, the alumino-silicate source, the quantity of water required for adequate workability and curing conditions, was studied. The need for post-curing desalination was also considered envisaging their application in the restoration of outdoor historical architectural tiles frequently exposed to adverse environmental conditions. The possible advantages and disadvantages of the use of geopolymers in the conservation of tiles are also discussed. The results obtained reveal that geopolymers pastes are a promising material for the restoration of tiles, when compared to other solutions currently in use.
Constitutive Model for Hot Deformation of the Cu-Zr-Ce Alloy
NASA Astrophysics Data System (ADS)
Zhang, Yi; Sun, Huili; Volinsky, Alex A.; Wang, Bingjie; Tian, Baohong; Liu, Yong; Song, Kexing
2018-02-01
Hot compressive deformation behavior of the Cu-Zr-Ce alloy has been investigated according to the hot deformation tests in the 550-900 °C temperature range and 0.001-10 s-1 strain rate range. Based on the true stress-true strain curves, the flow stress behavior of the Cu-Zr-Ce alloy was investigated. Microstructure evolution was observed by optical microscopy. Based on the experimental results, a constitutive equation, which reflects the relationships between the stress, strain, strain rate and temperature, has been established. Material constants n, α, Q and ln A were calculated as functions of strain. The equation predicting the flow stress combined with these materials constants has been proposed. The predicted stress is consistent with experimental stress, indicating that developed constitutive equation can adequately predict the flow stress of the Cu-Zr-Ce alloy. Dynamic recrystallization critical strain was determined using the work hardening rate method. According to the dynamic material model, the processing maps for the Cu-Zr and Cu-Zr-Ce alloy were obtained at 0.4 and 0.5 strain. Based on the processing maps and microstructure observations, the optimal processing parameters for the two alloys were determined, and it was found that the addition of Ce can promote the hot workability of the Cu-Zr alloy.
Microstructural Characterization and Modeling of SLM Superalloy 718
NASA Technical Reports Server (NTRS)
Smith, Tim M.; Sudbrack, Chantal K.; Bonacuse, Pete; Rogers, Richard
2017-01-01
Superalloy 718 is an excellent candidate for selective laser melting (SLM) fabrication due to a combination of excellent mechanical properties and workability. Predicting and validating the microstructure of SLM-fabricated Superalloy 718 after potential post heat-treatment paths is an important step towards producing components comparable to those made using conventional methods. At present, obtaining accurate volume fraction and size measurements of gamma-double-prime, gamma-prime and delta precipitates has been challenging due to their size, low volume fractions, and similar chemistries. A technique combining high resolution distortion corrected SEM imaging and with x-ray energy dispersive spectroscopy has been developed to accurately and independently measure the size and volume fractions of the three precipitates. These results were further validated using x-ray diffraction and phase extraction methods and compared to the precipitation kinetics predicted by PANDAT and JMatPro. Discrepancies are discussed in context of materials properties, model assumptions, sampling, and experimental errors.
NASA Technical Reports Server (NTRS)
1990-01-01
Johnson High School, Huntsville, Alabama started an international magnet program in 1987. One of the courses in the curriculum was in space science. They appealed to Marshall Space Flight Center (MSFC) when they couldn't find a suitable textbook, nor locate other classes in space science to provide a guideline. MSFC agreed to help and placed the school under an official 'Adopt-A-School' program. MSFC's chief scientist and others at the space center helped prepare a very comprehensive space science program. Examples of the subjects covered include problems of space travel, materials processing in space, technology utilization, robotics, space colonization, etc. MSFC followed up by working with Johnson High to determine if the curriculum is generally usable and workable. If it is, MSFC may make it available to other schools. MSFC not only developed the space science curriculum; they continue to support the program by sponsoring hands- on activities and tours of space research facilities.
The Effect of the Kind of Sands and Additions on the Mechanical Behaviour of S.C.C
NASA Astrophysics Data System (ADS)
Zeghichi, L.; Benghazi, Z.; Baali, L.
The sand is an inert element essential in the composition of concrete; its use ensures granular continuity between the cement and gravel for better cohesion of concrete. This paper presents the results of a study that investigated the influence of sand quality on the properties of fresh and hardened self-compacting concrete (SCC). The dune sands are very fine materials characterized by a high intergranular porosity, high surface area and low fineness modulus; on the other hand crushed (manufactured) sand has a high rate into thin and irregular shapes which are influencing the workability of concrete. The amount of dune sand varies from (0% 50%, to 100%) by weight of fine aggregates. The effect of additions is also treated (blast furnace slag and lime stone) The results show that the rheological properties favour the use of dune sands; however the mechanical properties support the use of crushed sand.
Effect of Power Exchange of India: An Overview and Key Issues
NASA Astrophysics Data System (ADS)
Singh, A.; Chauhan, D. S.; Upadhdhyay, K. G.
2013-09-01
There stands no guarantee that if potential market participants are simply provided with the opportunity for trading electricity, there shall be an efficient wholesale electricity market. India, as well as various other developed countries, relies on voluntary agreements as far as electricity trading is concerned. Self, private initiatives to standardize and commodities contracts play an important role in increasing the trading volume to improve efficiency, in developed countries. In accordance with their experiences, this paper suggested a specific strategy to promote bilateral/OTC trading; hence, India needed to develop a master agreement for electricity contracts. This paper discusses that the creating power exchange for short-term trading in the spot market materializing the contract for the convenience of market participants stands particularly important and henceforth is a necessary factor to make sure that spot market is workable and competitive prior to developing a financial contract for electricity trading.
NASA Technical Reports Server (NTRS)
Lahoti, G. D.; Akgerman, N.; Altan, T.
1978-01-01
Mild steel (AISI 1018) was selected as model cold rolling material and Ti-6A1-4V and Inconel 718 were selected as typical hot rolling and cold rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape rolling process were developed. These models utilized the upper bound and the slab methods of analysis, and were capable of predicting the lateral spread, roll separating force, roll torque, and local stresses, strains and strain rates. This computer-aided design system was also capable of simulating the actual rolling process, and thereby designing the roll pass schedule in rolling of an airfoil or a similar shape.
Radio- and photoluminescence properties of Ce/Tb co-doped glasses with huntite-like composition
NASA Astrophysics Data System (ADS)
Lorenzi, Roberto; Golubev, Nikita V.; Ziaytdinova, Mariyam Z.; Jarý, Vítězslav; Babin, Vladimir; Malashkevich, Georgii E.; Paleari, Alberto; Sigaev, Vladimir N.; Fasoli, Mauro; Nikl, Martin
2018-04-01
Optical properties of yttria-aluminoborate (YAB) glasses with general composition 10(CexTbyY(1-x-y))-30Al2O3-60B2O3 are investigated and compared with data available on YAB crystals with huntite-like structure. Ce doped samples show optical features ascribable to preferential location of rare earth ions in sites with specific geometry similar to that observed in crystalline structures. Samples prepared with Tb ions as emission activator and Ce ions as sensitizer have been studied within the framework of non-radiative energy transfer. The resulting Förster radius is of 4.6 ± 0.5 Å comparable with that observed in Ce/Tb co-doped YAl3(BO3)4 crystals. The investigated materials possess radio- and photoluminescence emission efficiencies and performances comparable to that of crystalline counterparts with the advantage of having easiness of preparation and workability typical of glassy systems.
Cyberbullying: the challenge to define.
Langos, Colette
2012-06-01
Cyberbullying is a reality of the digital age. To address this phenomenon, it becomes imperative to understand exactly what cyberbullying is. Thus, establishing a workable and theoretically sound definition is essential. This article contributes to the existing literature in relation to the definition of cyberbullying. The specific elements of repetition, power imbalance, intention, and aggression, regarded as essential criteria of traditional face-to-face bullying, are considered in the cyber context. It is posited that the core bullying elements retain their importance and applicability in relation to cyberbullying. The element of repetition is in need of redefining, given the public nature of material in the online environment. In this article, a clear distinction between direct and indirect cyberbullying is made and a model definition of cyberbullying is offered. Overall, the analysis provided lends insight into how the essential bullying elements have evolved and should apply in our parallel cyber universe.
Ahrens, E.H.
1998-07-07
An ultrafine cementitious grout is described having a particle size 90% of which are less than 6 {micro}m in diameter and an average size of about 2.5 {micro}m or less, and preferably 90% of which are less than 5 {micro}m in diameter and an average size of about 2 {micro}m or less containing Portland cement, pumice as a pozzolanic material and superplasticizer in the amounts of about 40 wt. % to about 50 wt. % Portland cement; from about 50 wt. % to about 60 wt. % pumice containing at least 60% amorphous silicon dioxide; and from 0.1 wt. % to about 1.5 wt. % superplasticizer. The grout is mixed with water in the W/CM ratio of about 0.4--0.6/1. The grout has very high strength and very low permeability with good workability. The ultrafine particle sizes allow for sealing of microfractures below 10 {micro}m in width. 4 figs.
Ahrens, Ernst H.
1998-01-01
An ultrafine cementitious grout having a particle size 90% of which are less than 6 .mu.m in diameter and an average size of about 2.5 .mu.m or less, and preferably 90% of which are less than 5 .mu.m in diameter and an average size of about 2 .mu.m or less containing Portland cement, pumice as a pozzolanic material and superplasticizer in the amounts of about 40 wt. % to about 50 wt. % Portland cement; from about 50 wt. % to about 60 wt. % pumice containing at least 60% amorphous silicon dioxide; and from 0.1 wt. % to about 1.5 wt. % superplasticizer. The grout is mixed with water in the W/CM ratio of about 0.4-0.6/1. The grout has very high strength and very low permeability with good workability. The ultrafine particle sizes allow for sealing of microfractures below 10 .mu.m in width.
Thermo-mechanical behaviors of thermoplastic starch derived from sugar palm tree (Arenga pinnata).
Sahari, J; Sapuan, S M; Zainudin, E S; Maleque, M A
2013-02-15
In recent years, increasing environmental concerns focused greater attention on the development of biodegradable materials. A thermoplastic starch derived from bioresources, sugar palm tree was successfully developed in the presence of biodegradable glycerol as a plasticizer. Sugar palm starch (SPS) was added with 15-40 w/w% of glycerol to prepare workable bioplastics and coded as SPS/G15, SPS/G20, SPS/G30 and SPS/G40. The samples were characterized for thermal properties, mechanical properties and moisture absorption on exposure to humidity were evaluated. Morphological studies through scanning electron microscopy (SEM) were used to explain the observed mechanical properties. Generally, the addition of glycerol decrease the transition temperature of plasticized SPS. The mechanical properties of plasticized SPS increase with the increasing of glycerol but up to 30 w/w%. Meanwhile, the water absorption of plasticized SPS decrease with increasing of glycerol. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bulakh, Andrey
2016-04-01
Soap stone represents soft Proterozoic rock type from the deposit Nunnalahti situated on the western shore of the big Lake Pielinen in Eastern Finland. It consists of talc (40 - 50 %), magnesite MgCO3 (40 - 50 %), chlorite (5 - 8 %), dolomite, calcite, etc. The colour of the stone is very spectacular and varies from yellow and brownish-yellow to grey, greenish grey. The soft stone is a highly workable material for a sculptor's chisel. It was one of the most popular ornamental rocks used architecture of the Modern style in St Petersburg, Helsinki, Turku, Tampere and other North European cities lately in the XIX-th centuries. Examples are given and discussed. References: Bulakh, A.G., Abakumova, N.B., and Romanovsky, J.V. St Petersburg: a History in Stone. 2010. Print House of St Petersburg State University. 173 p. (In English).
Properties of concrete containing scrap-tire rubber--an overview.
Siddique, Rafat; Naik, Tarun R
2004-01-01
Solid waste management is one of the major environmental concerns in the United States. Over 5 billion tons of non-hazardous solid waste materials are generated in USA each year. Of these, more than 270 million scrap-tires (approximately 3.6 million tons) are generated each year. In addition to this, about 300 million scrap-tires have been stockpiled. Several studies have been carried out to reuse scrap-tires in a variety of rubber and plastic products, incineration for production of electricity, or as fuel for cement kilns, as well as in asphalt concrete. Studies show that workable rubberized concrete mixtures can be made with scrap-tire rubber. This paper presents an overview of some of the research published regarding the use of scrap-tires in portland cement concrete. The benefits of using magnesium oxychloride cement as a binder for rubberized concrete mixtures are also presented. The paper details the likely uses of rubberized concrete.
Evaluation of Fracture Initiation in the Mannesmann Piercing Process
NASA Astrophysics Data System (ADS)
Fanini, S.; Ghiotti, A.; Bruschi, S.
2007-04-01
One of the challenging objectives in studying the Mannesmann piercing process is to predict the fracture initiation, known as "Mannesmann effect", in order to design and optimize the working parameters of the piercing process. The objective of the paper is to investigate the workability of a tube steel tested in the same conditions of the Mannesman piercing process. The stress and strain states as well as temperature fields arising during the process are identified through numerical simulations. The hot tensile test is chosen for fundamental studies on fracture initiation, as a tensile state of stress in the centre of the billet in the first stages of the piercing process before the plug arrival seems to be one of the main causes of the crack initiation. The material constants of energy-based models implemented in FEM codes are calculated and numerical results are compared with non-plug piercing tests carried out on the industrial plant.
Defining a successful commercial asteroid mining program
NASA Astrophysics Data System (ADS)
Andrews, Dana G.; Bonner, K. D.; Butterworth, A. W.; Calvert, H. R.; Dagang, B. R. H.; Dimond, K. J.; Eckenroth, L. G.; Erickson, J. M.; Gilbertson, B. A.; Gompertz, N. R.; Igbinosun, O. J.; Ip, T. J.; Khan, B. H.; Marquez, S. L.; Neilson, N. M.; Parker, C. O.; Ransom, E. H.; Reeve, B. W.; Robinson, T. L.; Rogers, M.; Schuh, P. M.; Tom, C. J.; Wall, S. E.; Watanabe, N.; Yoo, C. J.
2015-03-01
This paper summarizes a commercial Asteroid Mining Architecture synthesized by the Senior Space Design Class at the University of Washington in Winter/Spring Quarters of 2013. The main author was the instructor for that class. These results use design-to-cost development methods and focused infrastructure advancements to identify and characterize a workable space industrialization architecture including space transportation elements, asteroid exploration and mining equipment, and the earth orbit infrastructure needed to make it all work. Cost analysis predicts that for an initial investment in time and money equivalent to that for the US North Slope Oil Field, the yearly world supply of Platinum Group Metals could be increased by 50%, roughly 1500 t of LOX/LH2 propellant/year would be available in LEO, and very low cost solar panels could be assembled at GEO using asteroidal materials. The investment also would have a discounted net present value return on investment of 22% over twenty years.
NASA Astrophysics Data System (ADS)
Khrisat, Bilal; Hamarneh, Catrina; Majeed Mjalli, Abdul
The mosaic floor of Cosmas and Damian church was unearthed by the Yale University expedition in 1928 - 1929 and since then the mosaic floor has been exposed to the different agents of deterioration. In this paper a comprehensive approach of six phases is suggested to minimize the deterioration: documentation, deterioration diagnostics, treatment, conservation and management. Understanding the physical properties of the tesserae using petrographic technique was found to be useful for the understanding and conservation of the mosaic floors' materials. The use of diluted ammonia based solvent is proved to be the best workable treatment to remove the microorganism and to hinder the diffusion of the colonization of lichens on the mosaic floors in Jerash. With modification to suit local parameters, the comprehensive approach might be applied for mosaic floor with different context.
Ni{sub 3}Al technology transfer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sikka, V.K.; Viswanathan, S.; Santella, M.L.
1997-04-01
Ductile Ni{sub 3}Al and Ni{sub 3}Al-based alloys have been identified for a range of applications. These applications require the use of material in a variety of product forms such as sheet, plate, bar, wire, tubing, piping, and castings. Although significant progress has been made in the melting, casting, and near-net-shape forming of nickel aluminides, some issues still remain. These include the need for: (1) high-strength castable composition for many applications that have been identified; (2) castability (mold type, fluidity, hot-shortness, porosity, etc.); (3) weld reparability of castings; and (4) workability of cast or powder metallurgy product to sheet, bar, andmore » wire. The four issues listed above can be {open_quotes}show stoppers{close_quotes} for the commercial application of nickel aluminides. This report describes the work completed to address some of these issues during FY 1996.« less
High strength nickel-base alloy with improved oxidation resistance up to 2200 degrees F
NASA Technical Reports Server (NTRS)
Freche, J. C.; Waters, W. J.
1968-01-01
Modifying the chemistry of the NASA TAZ-8 alloy and utilizing vacuum melting techniques provides a high strength, workable nickel base superalloy with improved oxidation resistance for use up to 2200 degrees F.
Optimizing cementious content in concrete mixtures for required performance.
DOT National Transportation Integrated Search
2012-01-01
"This research investigated the effects of changing the cementitious content required at a given water-to-cement ratio (w/c) on workability, strength, and durability of a concrete mixture. : An experimental program was conducted in which 64 concrete ...
Criteria for Solid Waste Disposal Facilities: A Guide for Owners/Operators
EPA's continuing mission to establish the minimum national standards for landfill design, operation, and management that will enhance landfill safety and boost public confidence in landfills as a component of a workable integrated waste management system.
Evaluation of methods to calculate a wetlands water balance.
DOT National Transportation Integrated Search
2000-08-01
The development of a workable approach to estimating mitigation site water budgets is a high priority for VDOT and the wetlands research and design community in general as they attempt to create successful mitigation sites. Additionally, correct soil...
Muck Utilization in Urban Transportation Tunneling Process
DOT National Transportation Integrated Search
1977-12-01
The purpose of this study is to develop a workable approach to muck utilization for transit tunnels, including cut and cover construction, in the urban area. This report presents the results of a detailed investigation into the potential for muck uti...
Report of concrete pavement evaluation : project 105 C-4181-01 Donahoo Road, Wyandotte County.
DOT National Transportation Integrated Search
2013-12-01
The physical properties of hardened concrete cores and fresh concrete test results were compared with aggregate : gradation workability differences. The concrete cores were taken from a rural two-lane concrete road in northeastern Kansas : constructe...
ERIC Educational Resources Information Center
Rose, Homer C., Jr.; Hample, Stephen R.
1982-01-01
Considerations that can help colleges and universities develop institutionally specific strategies for planning faculty reductions are addressed. It is suggested that an institution can provide a fair and workable reduction plan if it: thoroughly explores alternatives to faculty layoffs; develops explicit standards and procedures for reduction…
EPA's mission to establish the minimum national standards for landfill design, operation, and management that will enhance landfill safety and boost public confidence in landfills as a component of a workable integrated waste management system.
Optics from Euclid to Huygens.
Herzberger, M
1966-09-01
The salient contributions of writers on optics from Euclid to Newton and Huygens are outlined, with a workable bibliography, to encourage present-day workers to restudy the classical writings and to find ideas that lie outside the paths that orthodox optical science has taken.
The Virginia Department of Transportation's statistical specification for hydraulic cement concrete.
DOT National Transportation Integrated Search
1990-01-01
This report reviews some of the principles relating to the application of statistical concepts to be used in the quality assurance and acceptance testing of hydraulic cement concrete. The problems encountered in developing a workable system without a...
ERIC Educational Resources Information Center
Lawson, Robert F.; Ghosh, Ratna
1986-01-01
Discusses Canada's problems in searching for a national identity and the controversy of the Federal policy of multiculturalism. Presents its objectives within a bilingual framework and the contradictions involved. Suggests a workable model involving assimilation conditioned by regional or local circumstances, useful also as a development strategy.…
Circling through Text: Teaching Research through Multigenre Writing.
ERIC Educational Resources Information Center
Grierson, Sirpa T.
1999-01-01
Describes how the author incorporated her requirements for a term research paper into multigenre writing. Discusses what multigenre is, how it can be taught and assessed, and what makes it such a rich, workable alternative to the traditional research assignment. (SR)
Advertising Content in Physical Activity Print Materials.
ERIC Educational Resources Information Center
Cardinal, Bradley J.
2002-01-01
Evaluated the advertising content contained in physical activity print materials. Analysis of print materials obtained from 80 sources (e.g., physicians' offices and fitness events) indicated that most materials contained some form of advertising. Materials coming from commercial product vendors generally contained more advertising than materials…
Auditory Localization: An Annotated Bibliography
1983-11-01
tranverse plane, natural sound localization in ,-- both horizontal and vertical planes can be performed with nearly the same accuracy as real sound sources...important for unscrambling the competing sounds which so often occur in natural environments. A workable sound sensor has been constructed and empirical
DOT National Transportation Integrated Search
2016-10-01
The Louisiana Transportation Research Center has worked closely with the Bridge : Design section of the Louisiana Department of Transportation and Development : (DOTD) to develop a workable specification for standard and localized roughness : of brid...
ERIC Educational Resources Information Center
Bentsen, Lloyd
1982-01-01
Discusses the need to formulate a coherent trade policy in response to international economic realities. The author argues against a return to trade protectionism and supports efforts to establish workable reciprocity agreements. Increasing import tariffs on high technology products would control access to American markets. (AM)
Annual report of Iowa Highway Research Board research and development activities FY 2010.
DOT National Transportation Integrated Search
2010-12-01
The Highway Division of the Iowa Department of Transportation (Iowa DOT) engages in research and : development for two reasons: first, to find workable solutions to the many problems that require more than : ordinary, routine investigation; and secon...
Being a Teacher of the Behavior Disordered.
ERIC Educational Resources Information Center
Dolce, Russell
1984-01-01
Draws on 13 years experience teaching behavior-disordered students to identify effective teaching methods. Discusses the importance of honesty, fairness, consistency, persistence, intuition, praise, and humor in the teacher-student relationship. Provides eight guidelines for developing a workable and suitable classroom reward system. (JHZ)
A WORKABLE DEFINITION OF SUCCESS
The most desirable definition of success from the point of view of environmental stewardship is to treat the entire plume to MCLs. Technically, has proven impossible to attain at many sites. A less desirable definition of success is to contain the source of contamination and tr...
Investigation of optimize graded concrete for Oklahoma : phase 1 : final report.
DOT National Transportation Integrated Search
2013-10-01
Optimized Graded Concrete has been a subject widely discussed through the history of concrete. Since aggregates make up over 70% of the volume in a mixture, gradation is critical to the strength, workability, and durability of concrete. In practice o...
ERIC Educational Resources Information Center
Piascik, Mary M.; Lubawy, William C.
1988-01-01
Inclusion of a course in the pharmacy curriculum that deals primarily with the immune system, its function, malfunction, and therapeutic intervention provides what appears to be a workable focus for discussion of biotechnology. (MSE)
ALLOY FOR USE IN NUCLEAR FISSION
Spedding, F.A.; Wilhelm, H.A.
1958-03-11
This patent relates to an alloy composition capable of functioning as a solid homogeneous reactor fuel. The alloy consists of a beryllium moderator, together with at least 0.7% of U/sup 235/, and up to 50% thorium to give increased workability to the alloy.
Analytical study on the suitability of using bentonite coated gravel as a landfill liner material
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roberts, Anel A.; Shimaoka, Takayuki
2008-12-15
This study investigates the feasibility of using bentonite coated gravel (BCG) as a liner material for waste landfills. BCG has proven to be a very effective capping material/method for the remediation of contaminated sediments in aquatic environments. The concept of BCG is similar to that of peanuts/almonds covered with chocolate; each aggregate particle has been covered with the clayey material. Laboratory tests were aimed at evaluating regulated and non-regulated factors for liner materials, i.e., permeability and strength. Tests included X-ray diffraction, methylene blue absorption, compaction, free swelling, permeability, 1D consolidation, triaxial compression and cone penetration. The compactive efforts used formore » this study were the reduced Proctor, standard Proctor, intermediate Proctor, modified Proctor and super modified Proctor. The compactive energy corresponding to each effort, respectively, is as follows: 355.5, 592.3, 1196.3, 2693.3, and 5386.4 kJ/m{sup 3}. Results revealed that even though aggregate content represents 70% of the weight of the material, hydraulic conductivities as low as 6 x 10{sup -10} cm/s can be achieved when proper compactive efforts are used. Compressibility is very low for this material even at low (or no) compactive efforts. Results also demonstrated how higher compactive efforts can lower the permeability of BCG; however, over-compaction creates fractures in the aggregate core of BCG that could increase permeability. Moreover, higher compactive efforts create higher swelling pressures that could compromise the performance of a barrier constructed using BCG. As a result of this study, moderate compactive efforts, i.e., intermediate Proctor or modified Proctor, are recommended for constructing a BCG barrier. Using moderate compactive efforts, very low hydraulic conductivities, good workability and good trafficability are easily attainable.« less
Analytical study on the suitability of using bentonite coated gravel as a landfill liner material.
Roberts, Anel A; Shimaoka, Takayuki
2008-12-01
This study investigates the feasibility of using bentonite coated gravel (BCG) as a liner material for waste landfills. BCG has proven to be a very effective capping material/method for the remediation of contaminated sediments in aquatic environments. The concept of BCG is similar to that of peanuts/almonds covered with chocolate; each aggregate particle has been covered with the clayey material. Laboratory tests were aimed at evaluating regulated and non-regulated factors for liner materials, i.e., permeability and strength. Tests included X-ray diffraction, methylene blue absorption, compaction, free swelling, permeability, 1D consolidation, triaxial compression and cone penetration. The compactive efforts used for this study were the reduced Proctor, standard Proctor, intermediate Proctor, modified Proctor and super modified Proctor. The compactive energy corresponding to each effort, respectively, is as follows: 355.5, 592.3, 1196.3, 2693.3, and 5386.4 kJ/m(3). Results revealed that even though aggregate content represents 70% of the weight of the material, hydraulic conductivities as low as 6 x 10(-10)cm/s can be achieved when proper compactive efforts are used. Compressibility is very low for this material even at low (or no) compactive efforts. Results also demonstrated how higher compactive efforts can lower the permeability of BCG; however, over-compaction creates fractures in the aggregate core of BCG that could increase permeability. Moreover, higher compactive efforts create higher swelling pressures that could compromise the performance of a barrier constructed using BCG. As a result of this study, moderate compactive efforts, i.e., intermediate Proctor or modified Proctor, are recommended for constructing a BCG barrier. Using moderate compactive efforts, very low hydraulic conductivities, good workability and good trafficability are easily attainable.
Carbon Nanotube Chopped Fiber for Enhanced Properties in Additive Manufacturing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Menchhofer, Paul A.; Johnson, Joseph E.; Lindahl, John M.
2016-06-06
Nanocomp Technologies, Inc. is working with Oak Ridge National Laboratory to develop carbon nanotube (CNT) composite materials and evaluate their use in additive manufacturing (3D printing). The first phase demonstrated feasibility and improvements for carbon nanotube (CNT)- acrylonitrile butadiene styrene (ABS) composite filaments use in additive manufacturing, with potential future work centering on further improvements. By focusing the initial phase on standard processing methods (developed mainly for the incorporation of carbon fibers in ABS) and characterization techniques, a basis of knowledge for the incorporation of CNTs in ABS was learned. The ability to understand the various processing variables is criticalmore » to the successful development of these composites. From the degradation effects on ABS (caused by excessive temperatures), to the length of time the ABS is in the melt state, to the order of addition of constituents, and also to the many possible mixing approaches, a workable flow sequence that addresses each processing step is critical to the final material properties. Although this initial phase could not deal with each of these variables in-depth, a future study is recommended that will build on the lessons learned for this effort.« less
Alkali-silica reactivity of expanded glass granules in structure of lightweight concrete
NASA Astrophysics Data System (ADS)
Bumanis, G.; Bajare, D.; Locs, J.; Korjakins, A.
2013-12-01
Main component in the lightweight concrete, which provides its properties, is aggregate. A lot of investigations on alkali silica reaction (ASR) between cement and lightweight aggregates have been done with their results published in the academic literature. Whereas expanded glass granules, which is relatively new product in the market of building materials, has not been a frequent research object. Therefore lightweight granules made from waste glass and eight types of cement with different chemical and mineralogical composition were examined in this research. Expanded glass granules used in this research is commercially available material produced by Penostek. Lightweight concrete mixtures were prepared by using commercial chemical additives to improve workability of concrete. The aim of the study is to identify effect of cement composition to the ASR reaction which occurs between expanded glass granules and binder. Expanded glass granules mechanical and physical properties were determined. In addition, properties of fresh and hardened concrete were determined. The ASR test was processed according to RILEM AAR-2 testing recommendation. Tests with scanning electron microscope and microstructural investigations were performed for expanded glass granules and hardened concrete specimens before and after exposing them in alkali solution.
[Osteosynthesis in facial bones: silicon nitride ceramic as material].
Neumann, A; Unkel, C; Werry, C; Herborn, C U; Maier, H R; Ragoss, C; Jahnke, K
2006-12-01
The favorable properties of silicon nitride (Si3N4) ceramic, such as high stability and biocompatibility suggest its biomedical use as an implant material. The aim of this study was to test its suitability for osteosynthesis. A Si3N4 prototype minifixation system was manufactured and implanted for osteosynthesis of artificial frontal bone defects in three minipigs. After 3 months, histological sections, CT and MRI scans were obtained. Finite element modeling (FEM) was used to simulate stresses and strains on Si3N4 miniplates and screws to calculate survival probabilities. Si3N4 miniplates and screws showed satisfactory intraoperative workability. There was no implant loss, displacement or fracture. Bone healing was complete in all animals and formation of new bone was observed in direct contact to the implants. Si3N4 ceramic showed a good biocompatibility outcome both in vitro and in vivo. This ceramic may serve as biomaterial for osteosynthesis, e.g. of the midface including reconstruction of the floor of the orbit and the skull base. Advantages compared to titanium are no risk of implantation to bone with mucosal attachment, no need for explantation, no interference with radiological imaging.
Blasted copper slag as fine aggregate in Portland cement concrete.
Dos Anjos, M A G; Sales, A T C; Andrade, N
2017-07-01
The present work focuses on assessing the viability of applying blasted copper slag, produced during abrasive blasting, as fine aggregate for Portland cement concrete manufacturing, resulting in an alternative and safe disposal method. Leaching assays showed no toxicity for this material. Concrete mixtures were produced, with high aggregate replacement ratios, varying from 0% to 100%. Axial compressive strength, diametrical compressive strength, elastic modulus, physical indexes and durability were evaluated. Assays showed a significant improvement in workability, with the increase in substitution of fine aggregate. With 80% of replacement, the concrete presented lower levels of water absorption capacity. Axial compressive strength and diametrical compressive strength decreased, with the increase of residue replacement content. The greatest reductions of compressive strength were found when the replacement was over 40%. For tensile strength by diametrical compression, the greatest reduction occurred for the concrete with 80% of replacement. After the accelerated aging, results of mechanic properties showed a small reduction of the concrete with blasted copper slag performance, when compared with the reference mixture. Results indicated that the blasted copper slag is a technically viable material for application as fine aggregate for concrete mixtures. Copyright © 2017 Elsevier Ltd. All rights reserved.
The evolution of our knowledge of HIV-associated kidney disease in Africa.
Swanepoel, Charles R; Wearne, Nicola; Duffield, Maureen S; Okpechi, Ikechi G
2012-10-01
Human immunodeficiency virus (HIV) infection started in Africa circa 1930. South Africa has the highest prevalence rate in the world. Although reports of HIV-associated nephropathy (HIVAN) appeared in the early 1980s, the earliest report from sub-Saharan Africa (SSA) came in 1994. Geographical, socioeconomic, political, and ethical factors have worked in concert to shape the character of HIV disease as it is seen in SSA. Political leaders within SSA have, through their actions, significantly contributed to the incidence of HIV infection. Black females, who often face cultural suppression and disadvantage, have a higher prevalence of HIV than males. Too few studies and outcomes data have bedeviled the statistics in SSA in relation to HIVAN prevalence and its management. Much of what is written is approximation and anecdotal. The largest reliable biopsy series comes from the University of Cape Town, where a workable classification of HIVAN has been developed to enable standardization of terminology. Histologic and clinical prognostic indicators with outcomes have been evaluated using this classification. Patients with HIV who present with acute kidney injury appear to have mainly acute tubular necrosis due to sepsis, dehydration, and nephrotoxic drugs. Since the rollout of combination antiretroviral therapy, the extent of HIV infection and kidney disease continues to be modified and possibly retarded. Copyright © 2012 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Chemical modification of uniform soils and soils with high/low plasticity index.
DOT National Transportation Integrated Search
2016-08-01
The addition of chemicals into the subgrade has been widely used during construction to improve the soil properties. The chemicals, often Lime Kiln Dust (LKD) and Portland cement, are added to the soil to improve its workability, compactability and e...
Classroom Management in the Elementary Grades. Research Series No. 32.
ERIC Educational Resources Information Center
Brophy, Jere E.; Putnam, Joyce G.
The literature on elementary school classroom management is reviewed. Topics include student characteristics and individual differences, preparing the classroom as a learning environment, organizing instruction and support activities to maximize student engagement in productive tasks, developing workable housekeeping procedures and conduct rules,…
Code of Federal Regulations, 2010 CFR
2010-07-01
... workable program. The right of orderly campus dissent is recognized. However, anti-ROTC activities which... accomplish program objectives of the host institution. Activities which are part of the host school's... that each cadet realizes the importance of choice of branch preferences and what is involved in making...
DOT National Transportation Integrated Search
2013-12-01
The physical properties of hardened concrete cores and fresh concrete test results were compared with aggregate gradation workability differences. The concrete cores were taken from a rural two-lane concrete road in northeastern Kansas constructed in...
Final report : sampling plan for pavement condition ratings of secondary roads.
DOT National Transportation Integrated Search
1984-01-01
The purpose of this project was to develop a random sampling plan for use in selecting segments of the secondary highway system for evaluation under the Department's PMS. The plan developed is described here. It is a simple, workable, random sampling...
An adaptive bit synchronization algorithm under time-varying environment.
NASA Technical Reports Server (NTRS)
Chow, L. R.; Owen, H. A., Jr.; Wang, P. P.
1973-01-01
This paper presents an adaptive estimation algorithm for bit synchronization, assuming that the parameters of the incoming data process are time-varying. Experiment results have proved that this synchronizer is workable either judged by the amount of data required or the speed of convergence.
MSIAC’s M&S Journal Online: Volume 2, September 2006
2006-09-01
engineering fields, such as mechanical and electrical , rely on composability and interchangeability (substitutability) of components into workable systems...Terrain Data for the Vector-in-Command and Engineer Functional Area Models”, Technical Report GL-90-9, September 1990, USAEWES, Vicksburg 8. Frankenstein
Every Child. Volume 13, Number 2, 2007
ERIC Educational Resources Information Center
Elliott, Alison, Ed.
2007-01-01
The theme of this issue of "Every Child" is "Challenging Practice and Challenging Practices." It covers a range of issues challenging the images of a "traditional" children's service. Contents include an editorial by Alison Elliott, "Wise Vision, Workable Solutions and Early Childhood Action," a guest…
Policy-Making in a Negotiating Society
ERIC Educational Resources Information Center
Carey, William D.
1976-01-01
A national disenchantment with knowledge, which sets up a contest between reason and mindlessness, and a strong tilt in the direction of conservative fiscal policy are cited as cause for those seeking support for science to take the initiative and negotiate a workable policy future. (JT)
Criteria Underlying the Formation of Alternative IMS Configurations.
ERIC Educational Resources Information Center
Dave, Ashok
To assist the formation of IMS (Instructional Management System) configurations, three categories of characteristics are developed and explained. Categories 1 and 2 emphasize automation, and the necessity of forming workable configurations to carry out instructional management for Southwest Regional Laboratory developed instructional and/or…
Conditioned Demand and Professional Response.
ERIC Educational Resources Information Center
Rhoades, Gary
1984-01-01
Two basic features of British higher education administration bearing on the workability of recent Leverhulme study proposals for the future of British higher education are examined. Vertical integration, (the relationship of secondary and higher education systems) and a high degree of professionalism enhancing it will influence reforms…
Code of Federal Regulations, 2010 CFR
2010-04-01
... 23 Highways 1 2010-04-01 2010-04-01 false Objective. 669.5 Section 669.5 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS ENFORCEMENT OF HEAVY VEHICLE USE TAX § 669.5 Objective. The objective of this regulation is to establish realistic and workable...
A Workable In-Depth Curriculum Evaluation Plan.
ERIC Educational Resources Information Center
Wakim, Judith H.
1983-01-01
Describes the six-year evolution of a comprehensive evaluation plan used to enhance a nursing program. Includes the plan with specific questions, deadlines, and documentation procedures. The plan provides a rational basis for improvements, orients newcomers, and lets everyone know what their evaluation responsibilities are. (JOW)
NASA Astrophysics Data System (ADS)
Muthusamy, K.; Mohamad Hafizuddin, R.; Mat Yahaya, F.; Sulaiman, M. A.; Syed Mohsin, S. M.; Tukimat, N. N.; Omar, R.; Chin, S. C.
2018-04-01
Concerns regarding the negative impact towards environment due to the increasing use of natural sand in construction industry and dumping of industrial solid wastes namely coal bottom ash (CBA) and oil palm shell (OPS) has resulted in the development of environmental friendly lightweight concrete. The present study investigates the effect of coal bottom ash as partial fine aggregate replacement towards workability and compressive strength of oil palm shell lightweight aggregate concrete (OPS LWAC). The fresh and mechanical properties of this concrete containing various percentage of coal bottom ash as partial fine aggregate replacement were investigated. The result was compared to OPS LWAC with 100 % sand as a control specimen. The concrete workability investigated by conducting slump test. All specimens were cast in form of cubes and water cured until the testing age. The compressive strength test was carried out at 7 and 28 days. The finding shows that integration of coal bottom ash at suitable proportion enhances the strength of oil palm shell lightweight aggregate concrete.
Performance of steel wool fiber reinforced geopolymer concrete
NASA Astrophysics Data System (ADS)
Faris, Meor Ahmad; Abdullah, Mohd Mustafa Al Bakri; Ismail, Khairul Nizar; Muniandy, Ratnasamy; Ariffin, Nurliayana
2017-09-01
In this paper, performance of geopolymer concrete was studied by mixing of Class F fly ash from Manjung power station, Lumut, Perak, Malaysia with alkaline activator which are combination of sodium hydroxide and sodium silicate. Steel wool fiber were added into the geopolymer concrete as reinforcement with different weight percentage vary from 0 % - 5 %. Chemical compositions of Malaysian fly ash was first analyzed by using X-ray fluorescence. All geopolymer concrete reinforced with steel wool fiber with different weight percentage were tested in terms of density, workability, and compression. Result shows Malaysian fly ash identified by using XRF was class F. Density of geopolymer concrete close to density of OPC which is approximately 2400 kg/m3 and the density was increase gradually with the additions of steel fiber. However, the inclusions of steel fibers also shows some reduction to the workability of geopolymer concrete. Besides, the compressive strength was increased with the increasing of fibers addition until maximum of 18.6 % improvement at 3 % of steel fibers.
Effects of aggregate grading on the properties of steel fibre-reinforced concrete
NASA Astrophysics Data System (ADS)
Acikgens Ulas, M.; Alyamac, K. E.; Ulucan, Z. C.
2017-09-01
This study investigates the effects of changing the aggregate grading and maximum aggregate size (D max ) on the workability and mechanical properties of steel fibre-reinforced concrete (SFRC). Four different gradations and two different D max were used to produce SFRC mixtures with constant cement dosages and water/cement ratios. Twelve different concrete series were tested. To observe the properties of fresh concrete, slump and Ve-Be tests were performed immediately after the mixing process to investigate the effects of time on workability. The hardened properties, such as the compressive, splitting tensile and flexural strengths, were also evaluated. In addition, the toughness of the SFRC was calculated. Based on our test results, we can conclude that the grading of the aggregate and the D max have remarkable effects on the properties of fresh and hardened SFRC. In addition, the toughness of the SFRC was influenced by changing the grading of the aggregate and the D max .
View from the center: Supercities conference
NASA Astrophysics Data System (ADS)
Knox, J. B.
The Supercities Conference (26-30 October 1992) was the initial activity planned and executed by the Pacific Basin Study Center (PBSC), a research center founded by San Francisco State University and the University of California, Davis. The Conference focused on issues of environmental quality and the quest for sustainable development in the great urban centers—Supercities—of the Pacific. The Conference, with its working group process, highlighted the long-term commitment of the PBSC to education, training, and research in regard to environmental, energy, and resource utilization issues that challenge society now and the coming century. We define a "Supercity" as a large metropolitan area of about eight million population currently undergoing rapid growth in population and urbanization. Some of the cities considered at the conference are emerging "Supercities"—large urban complexes destined to soon be "Supercities". Supercities in both the developing and developed nations are at critical stages of development, with the size and number of Supercities appearing to be unstoppable. These urban centers and their surrounding areas are large users of resources and energy. In many cases, the national demand for energy and materials will be largely patterned by the strategies, management, and actions taken within the Supercities. It is for this reason that our focus is on these dynamic, urban entities of the Pacific. Appropriate technology transfer, sharing of common concerns and knowledge, and the seeking of workable conservation and remediation efforts within Supercities could improve living conditions within these centers, and address regional and global environmental issues in parallel. The Conference focused on urban air quality conditions in 14 metropolitan areas, common health impacts, and projected emissions; a working group process defined needed areas for research and development of key information. Through the medium of panels, the progress of several major cities in addressing urban air quality issues was reported, as well as the rationale for the documented successes of environmental improvement. The Conference played a key role in the definition of the early research directions of the PBSC, and in the establishment of a Pacific Basin network of researchers and planners committed to the pursuit of sustainable development.
NASA Astrophysics Data System (ADS)
Schloffer, Daniel; Bozorgi, Salar; Sherstnev, Pavel; Lenardt, Christian; Gollas, Bernhard
2017-11-01
The fabrication of thin foils of magnesium for use as anode material in rechargeable magnesium ion batteries is described. In order to improve its workability, the magnesium was alloyed by melting metallurgy with zinc and/or gadolinium, producing saturated solid solutions. The material was extruded to thin foils and rolled to a thickness of approximately 100 μm. The electrochemical behavior of Mg-1.63 wt% Zn, Mg-1.55 wt% Gd and Mg-1.02 wt% Zn-1.01 wt% Gd was studied in (PhMgCl)2-AlCl3/THF electrolyte by cyclic voltammetry and galvanostatic cycling in symmetrical cells. Analysis of the current-potential curves in the Tafel region and the linear region close to the equilibrium potential show almost no effect of the alloying elements on the exchange current densities (5-45 μA/cm2) and the transfer coefficients. Chemical analyses of the alloy surfaces and the electrolyte demonstrate that the alloying elements not only dissolve with the magnesium during the anodic half-cycles, but also re-deposit during the cathodic half-cycles together with the magnesium and aluminum from the electrolyte. Given the negligible corrosion rate in aprotic electrolytes under such conditions, no adverse effects of alloying elements are expected for the performance of magnesium anodes in secondary batteries.
Pozzolanic Activity Assessment of LUSI (LUmpur SIdoarjo) Mud in Semi High Volume Pozzolanic Mortar
Hardjito, Djwantoro; Antoni; Wibowo, Gunadi M.; Christianto, Danny
2012-01-01
LUSI mud obtained from the mud volcano in Sidoarjo, Indonesia, is a viable aluminosilicate material to be utilized as pozzolanic material. LUSI is an abbreviation of the local name of the mud, i.e., Lumpur Sidoarjo, meaning Sidoarjo mud. This paper reports the results of an investigation to assess the pozzolanic activity of LUSI mud, especially in semi high volume pozzolanic mortar. In this case, the amount of mud incorporated is between 30% to 40% of total cementitious material, by mass. The content of SiO2 in the mud is about 30%, whilst the total content of SiO2, Fe2O3 and Al2O3 is more than 70%. Particle size and degree of partial cement replacement by treated LUSI mud affect the compressive strength, the strength activity index (SAI), the rate of pozzolanic activity development, and the workability of mortar incorporating LUSI mud. Manufacturing semi high volume LUSI mud mortar, up to at least 40% cement replacement, is a possibility, especially with a smaller particle size of LUSI mud, less than 63 μm. The use of a larger percentage of cement replacement by LUSI mud does not show any adverse effect on the water demand, as the flow of the fresh mortar increased with the increase of percentage of LUSI mud usage.
Development of highly porous scaffolds based on bioactive silicates for dental tissue engineering
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goudouri, O.M., E-mail: menti.goudouri@ww.uni-erlangen.de; Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki; Theodosoglou, E.
Graphical abstract: - Highlights: • Synthesis of an Mg-based glass-ceramic via the sol–gel technique. • The heat treatment of the glass-ceramic promoted the crystallization of akermanite. • Akermanite scaffolds coated with gelatin were successfully fabricated. • An HCAp layer was developed on the surface of all scaffolds after 9 days in SBF. - Abstract: Various scaffolding materials, ceramics and especially Mg-based ceramic materials, including akermanite (Ca{sub 2}MgSi{sub 2}O{sub 7}) and diopside (CaMgSi{sub 2}O{sub 6}), have attracted interest for dental tissue regeneration because of their improved mechanical properties and controllable biodegradation. The aim of the present work was the synthesis ofmore » an Mg-based glass-ceramic, which would be used for the construction of workable akermanite scaffolds. The characterization of the synthesized material was performed by Fourier Transform Infrared Spectroscopy (FTIR) X-Ray Diffractometry (XRD) and Scanning Electron Microscopy (SEM). Finally, the apatite forming ability of the scaffolds was assessed by immersion in simulated body fluid. The scaffolds were fabricated by the foam replica technique and were subsequently coated with gelatin to provide a functional surface for increased cell attachment. Finally, SEM microphotographs and FTIR spectra of the scaffolds after immersion in SBF solution indicated the inorganic bioactive character of the scaffolds suitable for the intended applications in dental tissue engineering.« less
An Analysis of the Alteration Specialist Occupation.
ERIC Educational Resources Information Center
Buerkel, Elaine; Rehling, Joseph H.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the textile service occupation. The industry needs properly trained alteration specialists, bushelmen and dressmakers, in the repairing, remodeling, altering or renovating of garments. Their personal…
ERIC Educational Resources Information Center
Tolmach, Judy
This publication describes economical ways to provide better housing for students and provides examples of workable solutions to the problem at various colleges and universities. For more economical and better housing, the author recommends (1) humanizing existing dormitories by changing the standard double rooms into suites of bedrooms with a…
ERIC Educational Resources Information Center
Sills, Angelyn C.
1995-01-01
Describes a straightforward, workable strategy that involves a teacher checklist and short individual or student group conferences, with the goal of academic or behavioral improvements. Teachers can easily tick off marks on the checklist and return the form to the counselor; additionally, students can easily understand the format of the checklist.…
A Cognitive Perspective in the Treatment of Incarcerated Clients.
ERIC Educational Resources Information Center
Walsh, Thomas C.
1990-01-01
Proposes a cognitive therapy model as a workable approach in treating incarcerated clients. Reviews principal components and techniques of cognitive theory. Uses case vignettes to illustrate application of this approach. Delineates key features of cognitive model which relate to treatment of incarcerated population. (Author/ABL)
Yes, the GIGP Really Does Work--And Is Workable!
ERIC Educational Resources Information Center
Burrell, Quentin L.; Fenton, Michael R.
1993-01-01
Discusses the generalized inverse Gaussian-Poisson (GIGP) process for informetric modeling. Negative binomial distribution is discussed, construction of the GIGP process is explained, zero-truncated GIGP is considered, and applications of the process with journals, library circulation statistics, and database index terms are described. (50…
Repeated Prescribed Burning in Aspen
Donald A. Perala
1974-01-01
Infrequent burning weather, low flammability of the aspen-hardwood association, and prolific sprouting and seeding of shrubs and hardwoods made repeated dormant season burning a poor tool to convert good site aspen to conifers. Repeat fall burns for wildlife habitat maintenance is workable if species composition changes are not important.
Student Credit Card Debt in the 21st Century: Options for Financial Aid Administrators.
ERIC Educational Resources Information Center
Oleson, Mark
2001-01-01
Provides multiple workable solutions financial aid offices can offer students throughout their college experience to deal with debt: preventive solutions for avoiding problems with credit card debt, holistic solutions for other related problems, and remedial solutions for existing problems. (EV)
National Defense on the High Frontier.
ERIC Educational Resources Information Center
Graham, Daniel O.
1983-01-01
A new American defense policy based on satellites which can track down and destroy Soviet missiles is less expensive and more workable than is commonly believed. Such a policy would provide a greater margin of safety than the present policy of deterence based on mutually assured destruction. (IS)
QUANTITATIVE DECISION TOOLS AND MANAGEMENT DEVELOPMENT PROGRAMS.
ERIC Educational Resources Information Center
BYARS, LLOYD L.; NUNN, GEOFFREY E.
THIS ARTICLE OUTLINED THE CURRENT STATUS OF QUANTITATIVE METHODS AND OPERATIONS RESEARCH (OR), SKETCHED THE STRENGTHS OF TRAINING EFFORTS AND ISOLATED WEAKNESSES, AND FORMULATED WORKABLE CRITERIA FOR EVALUATING SUCCESS OF OPERATIONS RESEARCH TRAINING PROGRAMS. A SURVEY OF 105 COMPANIES REVEALED THAT PERT, INVENTORY CONTROL THEORY AND LINEAR…
Action Research and Narrative Inquiry: Five Principles for Validation Revisited
ERIC Educational Resources Information Center
Heikkinen, Hannu L. T.; Huttunen, Rauno; Syrjala, Leena; Pesonen, Jyri
2012-01-01
The article continues the discussion of the five quality principles proposed by Heikkinen, Huttunen, and Syrjala, published in 2007 in "Educational Action Research". In the present article, the authors reconsider the five principles: historical continuity; reflexivity; dialectics; workability; and evocativeness. These five principles are…
An Extension Case Study in Institutional Innovation: Microfinance Intermediary Formation
ERIC Educational Resources Information Center
Edelman, Mark A.
2015-01-01
An institutional innovation process led by Extension created a statewide microfinance intermediary. The intermediary provides business technical assistance and microloans to entrepreneurs having difficulty securing conventional credit but having workable business plans. The process included (1) gathering indicators of a problem; (2) formation of a…
Censorship: Managing the Controversy.
ERIC Educational Resources Information Center
National School Boards Association, Alexandria, VA.
In this monograph, certain viewpoints, strategies, and policy tips have been separated from the main text. These "notebooks" of information, taken together, comprise a useful handbook for school officials who want to recognize censorship, put it in perspective, and prepare for consequent controversy. The purpose is to provide workable strategies…
An Analysis of the Landscaping Occupation.
ERIC Educational Resources Information Center
Stemple, Lynn L.; Dilley, John E.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the landscape services occupation. Depending on the preparation and abilities of the individual student, he may enter the landscape area as (1) nursery worker, (2) landscape planter, (3) landscape…
Business Services' Impact on Student Retention: Exploring Student and Administrator Perceptions
ERIC Educational Resources Information Center
Hassabis, Haris
2014-01-01
High student attrition rates for first-year university students affect the financial and long-term sustainability of institutions. Previous researchers failed to provide workable solutions to improving student retention. This study was an exploration of students' and administrators' perceptions of business services and their potential impact on…
ERIC Educational Resources Information Center
Robinson, Andrew A.
1976-01-01
Describes four distinct periods in the history of black education in this country prefacing his description by the assertion that America's genius is its ability to weld together a nation of different peoples into a workable, if not efficient, social order. (Author/AM)
ERIC Educational Resources Information Center
Hoff, Dianne L.; Mitchell, Sidney N.
2010-01-01
Designing school accommodations for students with potentially life-threatening peanut allergies is a daunting challenge for schools. Parents of children with peanut allergies put a lot of pressure on schools to make them peanut-free, even though medical and legal experts say that is not a sound, or even workable, solution. One solution is to…
Improving Bilingual Program Management. A Handbook for Title VII Directors.
ERIC Educational Resources Information Center
DeGeorge, George P., Ed.
Filled with practical advice and workable techniques and strategies to help bilingual program directors deal with the problems they face, this handbook brings together ideas and suggestions from Title VII program directors, state coordinators, and superintendents with experience in bilingual programs. The handbook, written in question and answer…
Cyber Bullying and Academic Performance
ERIC Educational Resources Information Center
Faryadi, Qais
2011-01-01
This research investigates the emotional and physiological effects of cyber bullying on the university students. The primary objective of this investigation is to identify the victims of cyber bullying and critically analyze their emotional state and frame of mind in order to provide them with a workable and feasible intervention in fighting cyber…
Portfolios in Practice: What Is a Portfolio?
ERIC Educational Resources Information Center
Arter, Judith A.
A consortium effort sponsored by the Northwest Regional Evaluation Association has arrived at a workable definition of a portfolio that takes into account the viewpoints of teachers and those interested in large-scale assessment. The modified definition states that: "A student portfolio is a purposeful collection of student work that tells…
Can Your District Survive a Data Disaster?
ERIC Educational Resources Information Center
Smith, Gary
2011-01-01
School business administrators have long recognized the need for a workable data recovery plan regardless of cause. Yet many have not reassessed their current data backup and recovery capabilities, perhaps because they have not experienced a catastrophic failure. There are three reasons school business administrators may not realize or recognize…
Personality Types as an Indicator of Online Student Success and Retention
ERIC Educational Resources Information Center
Meredith, Ben P.
2011-01-01
With online education courses within public institutions realizing lower than average retention and success rates for students, current retention practices and models are falling woefully short of providing workable, viable answers to keeping students and helping them be successful without lowering academic standards. While a relationship between…
An Analysis of the Baking Occupation.
ERIC Educational Resources Information Center
Boyadjid, Thomas A; Paoletti, Donald J.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the baking occupation. Such tasks as choosing ingredients and the actual baking process are logical primary concerns, but also explored are the safety and sanitation factors and management problems in a…
Gardening for All: The Accessible Garden. Revised Edition.
ERIC Educational Resources Information Center
Brock, Holly; Mefford, Gayle
1990-01-01
This pamphlet presents some innovative thoughts and suggestions to make gardening an "accessible" activity for any gardener, able-bodied or disabled. For gardeners with special needs, workability of the garden must take precedence over a conventional garden design. Designs to consider include raised bed gardens, garden containers such as whiskey…
Copyright: A Guide for Public Humanities Projects. Federation Resources 3.
ERIC Educational Resources Information Center
Rozeen, Mark
As public humanities programs increasingly make use of media products, an understanding of copyrights is essential. Some problems pertaining to copyrights may be alleviated by advanced planning, a clear division of responsibilities, and by using reason to determine that policies are workable and fair. The problem involves a growing…
Appraisal and Evaluation: Chimera, Fantasy, or Practicality?
ERIC Educational Resources Information Center
Marland, Michael
1986-01-01
Looks beyond the threatening and remunerative aspects of teacher appraisal in the United Kingdom to the contribution that evaluation can make to professional and school development. Considers five sound reasons for appraisal, the roles and behaviors to be appraised, and some workable approaches and techniques. Effective leadership is the key.…
An Analysis of the Auto Mechanic Occupation.
ERIC Educational Resources Information Center
Conner, Michael; Thoman, LeRoy
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the auto mechanic occupation. It identifies the broad area of skills and knowledge necessary to perform various tasks involved in diagnosis, maintenance, and repair of automotive systems. Selected…
Planning the Library Media Center Facility for the 1990s and Beyond.
ERIC Educational Resources Information Center
Texas Education Agency, Austin.
This manual presents recommendations for incorporating present and future technological changes into workable, efficient, pleasant school library media facilities in two major sections: Planning the Facility and Activity Areas. The first section addresses the planning process (appointing the building committee, evaluating the library media…
ERIC Educational Resources Information Center
Florida A and M Univ., Tallahassee.
At the beginning of the l974-75 term, Florida A & M University innovated the concept of the miniquarter. Its central purpose was to foster the development of the collegiate life styles, attitudes, motivations, and work-study habits almost absolutely demanded by competitive curricula. The idea appeared to be rational, relevant, and workable.…
Classroom Dialogues: Connections amid Incongruities (New Teachers Workshop).
ERIC Educational Resources Information Center
Kroll, Catherine W.
1990-01-01
Describes the workable strategies a student teacher found to deal with student apathy and disinterest. Discusses the use of script writing; balancing "old" literature with writing hot off the presses; using writing about real subjects which captivate student interest to work on writing arguments; and exploring cultural incongruities through…
78 FR 75483 - Federal Travel Regulation (FTR); Relocation Allowances; Commuted Rate
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-12
... Allowances; Commuted Rate AGENCY: Office of Governmentwide Policy (OGP), U.S. General Services Administration (GSA). ACTION: Final rule. SUMMARY: The GSA, OGP, is providing a workable commuted rate to be used by.... 5724(c) requires that GSA maintain a commuted rate incorporating all aspects of household goods...
Dan Says - Continuum Magazine | NREL
good science will reward you with unexpected insights - some more profound than you ever could have insights we gain through the basic science we perform is essential to our applied technology R&D, and answer the fundamental questions of science. Their colleagues forge those new insights into workable
PROCESS OF PRODUCING ACTINIDE METALS
Magel, T.T.
1959-07-14
The preparation of actinide metals in workable, coherent form is described. In general, the objects of the invention are achieved by heating a mixture of an oxide and a halide of an actinide metal such as uranium with an alkali metal on alkaline earth metal reducing agent in the presence of iodine.
Analyzing Prosocial Content on T.V.
ERIC Educational Resources Information Center
Davidson, Emily S.; Neale, John M.
To enhance knowledge of television content, a prosocial code was developed by watching a large number of potentially prosocial television programs and making notes on all the positive acts. The behaviors were classified into a workable number of categories. The prosocial code is largely verbal and contains seven categories which fall into two…
An Analysis of the Automobile Sales Occupation.
ERIC Educational Resources Information Center
Bohac, Robert D.; Vernon, Robert C.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the auto sales occupation. The analysis follows the salesperson through the essential everyday performance of the tasks in the occupation. The duties involve the process of obtaining the prospects and…
DOT National Transportation Integrated Search
2009-03-01
Self-consolidating concrete (SCC) is a highly workable concrete that flows through densely reinforced or : complex structural elements under its own weight. The benefits of using SCC include: a) Reducing labor costs : by eliminating the need for mech...
How to Build Public Relationships That Motivate Real Support.
ERIC Educational Resources Information Center
Jackson, Patrick
1986-01-01
Public relations is a process that should produce relationships (not merely favorable public opinion) and should target a few opinion leaders and others who really care about individual schools. As chief public relations officers, principals need to understand the information diffusion process and use workable tactics to produce solid community…
Carbon Mineralization by Aqueous Precipitation for Beneficial Use of CO2 from Flue Gas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brent Constantz; Randy Seeker; Martin Devenney
2010-06-30
Calera's innovative Mineralization via Aqueous Precipitation (MAP) technology for the capture and conversion of CO{sub 2} to useful materials for use in the built environment was further developed and proven in the Phase 1 Department of Energy Grant. The process was scaled to 300 gallon batch reactors and subsequently to Pilot Plant scale for the continuous production of product with the production of reactive calcium carbonate material that was evaluated as a supplementary cementitious material (SCM). The Calera SCM{trademark} was evaluated as a 20% replacement for ordinary portland cement and demonstrated to meet the industry specification ASTM 1157 which ismore » a standard performance specification for hydraulic cement. The performance of the 20% replacement material was comparable to the 100% ordinary portland cement control in terms of compressive strength and workability as measured by a variety of ASTM standard tests. In addition to the performance metrics, detailed characterization of the Calera SCM was performed using advanced analytical techniques to better understand the material interaction with the phases of ordinary portland cement. X-ray synchrotron diffraction studies at the Advanced Photon Source in Argonne National Lab confirmed the presence of an amorphous phase(s) in addition to the crystalline calcium carbonate phases in the reactive carbonate material. The presence of carboaluminate phases as a result of the interaction of the reactive carbonate materials with ordinary portland cement was also confirmed. A Life Cycle Assessment was completed for several cases based on different Calera process configurations and compared against the life cycle of ordinary portland cement. In addition to the materials development efforts, the Calera technology for the production of product using an innovative building materials demonstration plant was developed beyond conceptual engineering to a detailed design with a construction schedule and cost estimate.« less
NASA Astrophysics Data System (ADS)
Jagalur Mahalingasharma, Srishaila; Prakash, Parasivamurthy; Vishwanath, K. N.; Jawali, Veena
2017-06-01
This paper presents experimental investigations made on the influence of chemical, physical, morphological and mineralogical properties of mineral admixtures such as fly ash, ground granulate blast furnace slag, metakaoline and micro silica used as a replacement of cement in self compacting concrete on workability and compressive strength. Nineteen concrete mixes were cast by replacing with cement by fly ash or ground granulated blast furnace slag as binary blend at 30%, 40%, 50% and with addition of micro silica and metakaoline at 10% as a ternary blend with fly ash, ground granulated blast furnace slag and obtained results were compare with control mix. Water powder ratio 0.3 and super plasticizer dosage 1% of cementitious material was kept constant for all the mixes. The self compacting concrete tested for slump flow, V-funnel, L-Box, J-Ring, T50, and compressive strength on concrete cube were determined at age of 3, 7, 28, 56, 90 days.
The politics of verification and the control of nuclear tests, 1945-1980
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallagher, N.W.
1990-01-01
This dissertation addresses two questions: (1) why has agreement been reached on verification regimes to support some arms control accords but not others; and (2) what determines the extent to which verification arrangements promote stable cooperation. This study develops an alternative framework for analysis by examining the politics of verification at two levels. The logical politics of verification are shaped by the structure of the problem of evaluating cooperation under semi-anarchical conditions. The practical politics of verification are driven by players' attempts to use verification arguments to promote their desired security outcome. The historical material shows that agreements on verificationmore » regimes are reached when key domestic and international players desire an arms control accord and believe that workable verification will not have intolerable costs. Clearer understanding of how verification is itself a political problem, and how players manipulate it to promote other goals is necessary if the politics of verification are to support rather than undermine the development of stable cooperation.« less
Galvanic corrosion behaviour of HE 20 / MDN 138 & HE 20 / MDN 250 alloys in natural seawater
NASA Astrophysics Data System (ADS)
Subramanian, G.; Parthiban, G. T.; Muthuraman, K.; Ramakrishna rao, P.
2016-09-01
In view of their excellent mechanical properties, workability and heat treatment characteristics, MDN 138 & MDN 250 have been widely used in missile, rocket and aerospace industries. With light weight and high performance characteristics HE 20 aluminium alloy acts as an important material in defence and aerospace applications. The galvanic corrosion behaviour of the metal combinations HE 20 / MDN 138 and HE 20 / MDN 250, with 1:1 area ratio, has been studied in natural seawater using the open well facility of CECRI's Offshore Platform at Tuticorin for a year. The open circuit potentials of MDN 138, MDN 250 and HE 20 of the individual metal, the mixed potential and galvanic current of the couples HE 20 / MDN 138 and HE 20 / MDN 250 were periodically monitored throughout the study period. The calcareous deposits on MDN 138 and MDN 250 were analysed using XRD. The results of the study reveal that that HE 20 has offered required amount of protection to MDN 138 & MDN 250.
The Feasibility of Palm Kernel Shell as a Replacement for Coarse Aggregate in Lightweight Concrete
NASA Astrophysics Data System (ADS)
Itam, Zarina; Beddu, Salmia; Liyana Mohd Kamal, Nur; Ashraful Alam, Md; Issa Ayash, Usama
2016-03-01
Implementing sustainable materials into the construction industry is fast becoming a trend nowadays. Palm Kernel Shell is a by-product of Malaysia’s palm oil industry, generating waste as much as 4 million tons per annum. As a means of producing a sustainable, environmental-friendly, and affordable alternative in the lightweight concrete industry, the exploration of the potential of Palm Kernel Shell to be used as an aggregate replacement was conducted which may give a positive impact to the Malaysian construction industry as well as worldwide concrete usage. This research investigates the feasibility of PKS as an aggregate replacement in lightweight concrete in terms of compressive strength, slump test, water absorption, and density. Results indicate that by using PKS for aggregate replacement, it increases the water absorption but decreases the concrete workability and strength. Results however, fall into the range acceptable for lightweight aggregates, hence it can be concluded that there is potential to use PKS as aggregate replacement for lightweight concrete.
Effect of chitosan ethers on fresh state properties of lime mortars
NASA Astrophysics Data System (ADS)
Vyšvařil, M.; Žižlavský, T.
2017-10-01
The fresh state properties of mortars are eminently important since determine the material workability and also have a great influence on its hardened state characteristics. In this paper, the behaviour of fresh lime mortars modified by etherified derivatives of chitosan (hydroxypropylchitosan (HPCH) and carboxymethylchitosan (CMCH)) is assessed with the purpose of exploring a new application of such derivatives as lime mortar admixtures. The rheological parameters (relative yield stress, consistency coefficient and fluidity index) and viscoelastic properties were correlated with flow table tests, relative density measurements, water retention abilities of mortars and air content in mortars. Results were seen to be strongly dependent on substituents of the chitosan. Non-ionic derivative (HPCH) had a plasticizing influence on the mortars; the ionic CMCH showed the thickening effect. The effect of chitosan ethers was found to be dosage-dependent. CMCH had low impact on water retention, while HPCH displayed high water retention capability. It was concluded, that the ionic derivative (CMCH) is very similar by its viscosity enhancing effect to starch ether.
Adsorption behaviour of SF6 decomposed species onto Pd4-decorated single-walled CNT: a DFT study
NASA Astrophysics Data System (ADS)
Cui, Hao; Zhang, Xiaoxing; Zhang, Jun; Tang, Ju
2018-07-01
Metal nanocluster decorated single-walled carbon nanotubes (SWCNT) with improved adsorption behaviour towards gaseous molecules compared with intrinsic ones, have been widely accepted as a workable media for gas interaction due to their strong catalysis. In this work, Pd4 cluster is determined as a catalytic centre to theoretically study the adsorption property of Pd4-decorated SWCNT upon SF6 decomposed species. Results indicate that Pd4-SWCNT possessing good responses and sensitivities towards three composed species of SF6 could realise selective detection for them according to the different conductivity changes resulting from the varying adsorption ability. The response of Pd4-SWCNT upon three molecules in order is SOF2 > H2S > SO2, and the conductivity of the proposed material is about to increase in SOF2 and H2S systems, while declining in SO2 system. Such conclusions would be helpful for experimentalists to explore novel SWCNT-based sensors in evaluating the operating state of SF6 insulation devices.
75 FR 80064 - National Offshore Safety Advisory Committee
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-21
... by coming to Room 5-0622, U.S. Coast Guard Headquarters Building, 2100 Second Street, SW., Washington... first come basis. Written material and requests to make oral presentations should be sent to Commander P... standards for Offshore Supply Vessels with a gross registered tonnage greater than 6000 GRT in light of the...
ERIC Educational Resources Information Center
Steiner, Stan
For more than 400 years the ancestors of the Mexican American have contributed to the spiritual and material wealth of this land, yet recognition of their cultural and national rights has been slow to come. Like the American Indians, Chicanos can claim, "We did not come to America, America came to us". As a conquered people, they have…
An Analysis of the Horticulture Equipment and Services Occupation.
ERIC Educational Resources Information Center
Harbage, Monroe; Lechner, Donald L.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the horticulture equipment and services occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Fourteen duties are…
Implementing the Regular Education Initiative in Secondary Schools: A Different Ball Game.
ERIC Educational Resources Information Center
Schumaker, Jean B.; Deshler, Donald D.
1988-01-01
The article reviews potential barriers to implementing the Regular Education Initiative (REI) in secondary schools and then discusses a set of factors central to developing a workable partnership, one that is compatible with the goals of the REI but that also responds to the unique parameters of secondary schools. (Author/DB)
Eliminating Standardized Tests in College Admissions: The New Affirmative Action?
ERIC Educational Resources Information Center
Zwick, Rebecca
1999-01-01
Eliminating the Scholastic Aptitude Test for college admissions might seem a form of covert affirmative action. Although it is possible to design a workable admissions policy that excludes standardized tests (as 15 percent of colleges have done), banishing admissions tests to further a social-policy goal indirectly is unsound policy. (Contains 25…
An Effective Approach to Drug Education.
ERIC Educational Resources Information Center
Frank, Peter R.
Traditionally, drug abuse education in the public schools has been approached through the use of scare tactics and scientific data. This document suggests that the old methods are not workable, and therefore attention should be directed toward helping the child develop a good self-concept and teaching decision-making skills. In the You and Your…
The Interactive Effects of Rules on Teaching Timetable Flexibility and Resource Utilization.
ERIC Educational Resources Information Center
Wesson, David A.
1995-01-01
Effect of administrative rules concerning scheduling on college faculty's productivity is examined. Three potential effects are that rules interact with other rules to produce rigidity; scheduling changes cause greater disruption as rules and rigidity increase; and at some point, rules prohibit creation of a workable schedule for teaching facility…
Pay-for-Knowledge Compensation Plans: Hypotheses and Survey Results.
ERIC Educational Resources Information Center
Gupta, Nina; And Others
1987-01-01
The authors describe the concept of "pay-for-knowledge" compensation plans and report results from a survey of 20 personnel directors in pay-for-knowledge plants. Results indicate that companies using this system have generally found it workable and feel it would be a mistake to revert to traditional compensation plans. (CH)
Building International Relations for Children through Sister Schools.
ERIC Educational Resources Information Center
Pryor, Carolyn B.
1992-01-01
Inspired by Sister Cities International and the NASSP's school-to-school exchange program, "sister school" pairings have proved to be workable educational programs with long-range impact on participants. Some post-cold war efforts include U.S.-USSR High School Academic Partnerships, Project Harmony, and Center for U.S.-USSR Initiatives.…
Tractor Hydraulics. A Teaching Reference.
ERIC Educational Resources Information Center
American Association for Vocational Instructional Materials, Athens, GA.
The manual was developed to help provide a better understanding of how and why hydraulic principles serve the purposes of weight reduction, increase of physical effort, and more precise control to machines of all types. The four components that are necessary to have a workable hydraulic system--a reservoir, a pump, a valve, and a motor (cylinder)…
SECOND-ORDER PROBLEMS IN STUDIES OF PERCEPTUAL DEVELOPMENT.
ERIC Educational Resources Information Center
WHITE, BURTON L.
RECENT RESEARCH FINDINGS ON THE PERCEPTUAL DEVELOPMENT OF YOUNG INFANTS WERE SURVEYED, AND THE NEED FOR SYNTHESIZING THESE NEW FINDINGS INTO WORKABLE CONCEPTS WAS SUGGESTED FOR THE FRUITFUL STUDY OF HIGHER ORDER CONSIDERATIONS IN THE FUTURE. A DISCUSSION WAS MADE ON THE DEVELOPMENTAL ISSUES OF--(1) SUPERORDINATE CATEGORIES OF PERCEPTUAL FUNCTION,…
An Analysis of the Billing and Bookkeeping Machine Operator Occupation.
ERIC Educational Resources Information Center
Six, Joseph E., Jr.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the billing and bookkeeping machine operating occupation. The analysis was written in general terms due to the diversity in bookkeeping machines on the market, increasing number and variation of the tasks…
Renewable energy and wildlife conservation
Khalil, Mona
2016-09-09
The renewable energy sector is rapidly expanding and diversifying the power supply of the country. Yet, as our Nation works to advance renewable energy and to conserve wildlife, some conflicts arise. To address these challenges, the U.S. Geological Survey (USGS) is conducting innovative research and developing workable solutions to reduce impacts of renewable energy production on wildlife.
A Love towards a Thing Eternal: Spinoza and the Classroom
ERIC Educational Resources Information Center
Shann, Steve; Bauer, Michele; Cunneen, Rachel; Troy, Jaki; Van Blerk, Courtney
2015-01-01
There is a growing concern about the struggles of early career teachers and an understandable questioning of the preparation being offered by teacher education courses. Are our preservice teachers being given workable strategies and techniques to allow them to survive the early years? Is it strategies and techniques that are primarily at issue…
An Analysis of the Commercial Art Occupation.
ERIC Educational Resources Information Center
Mowen, Kenneth A.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the commercial artist occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Seventeen duties are broken down into a…
Inferior Blueberries and Other Excuses I've Heard
ERIC Educational Resources Information Center
Van Winkle, David
2005-01-01
In this article, the author relates the blueberry story, as one of many excuses for barely advancing the status quo, and suggests a workable framework that is common to both education and business. Unfortunately, many business and education leaders seem intent on fixing specific issues and fail to acquire a systemic perspective. These isolated…
Health Education Teaching Ideas: Secondary. Revised Edition.
ERIC Educational Resources Information Center
Loya, Richard, Ed.; Bensley, Loren B., Jr., Ed.
Part I of this teaching guide contains teaching strategies which originally appeared in the "Journal of Health Education" (JHE) and were included in the first edition of this guide, published in 1983. Part II includes teaching strategies published in JHE since 1983. The guide is designed to be a reference for those seeking workable ideas in…
An Analysis of the Machine Trades Occupation.
ERIC Educational Resources Information Center
Hall, Charles W.; Emory, Harold L.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the machine trades occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Fifteen duties are broken down into a number…
Designing a Workable Framework for Evaluating Distance Language Instruction
ERIC Educational Resources Information Center
Madyarov, Irshat
2009-01-01
Teaching foreign languages at distance is now becoming widespread; so is the need for evaluating online language courses. This article discusses an example of a framework that was applied to evaluate an online English as a foreign language (EFL) course at a Middle Eastern university. The development of the framework investigated areas of interest…
Global Interdependence Education: A Key Resource for the Transformation of Civilization.
ERIC Educational Resources Information Center
Siegmund, Mark
1983-01-01
We must acquire the fullest understanding and use of our life support system and begin a movement of energies away from scarcity and toward self-sufficiency. Global interdependence education can assist in this process. Educators will be called on to demonstrate the workability and necessity of whole-system approaches. (SR)
An Analysis of the Laboratory Assisting Occupation.
ERIC Educational Resources Information Center
McGee, Patricia; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the laboratory assistant occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Eleven duties are broken down into a…
ERIC Educational Resources Information Center
Deek, Fadi; Espinosa, Idania
2005-01-01
Traditionally, novice programmers have had difficulties in three distinct areas: breaking down a given problem, designing a workable solution, and debugging the resulting program. Many programming environments, software applications, and teaching tools have been developed to address the difficulties faced by these novices. Along with advancements…
ERIC Educational Resources Information Center
Goldman, Paul; Tindal, Gerald
This paper explores the difficulties of extending good, workable educational ideas to entire schools or districts. Two restructured schools that participated in a 4-year collaborative project that involved multi-age primary classrooms, inclusion of special-needs students in regular classrooms, and increasing specificity in assessing student…
ERIC Educational Resources Information Center
National Univ. Extension Association, Washington, DC.
Seven 1979 innovative programs in continuing education are described which won awards from the American College Testing Program and the National University Extension Association. Awards were granted according to programs' transferability, innovativeness, workability, and impact in one of four categories: instructional programs, student services…
Chapter Innovators Guide, 2000: Models of Innovation Award Winners.
ERIC Educational Resources Information Center
National FFA Organization, Indianapolis, IN.
This guide presents the Future Farmers of America (FFA) 2000 Model of Innovation award winners' projects. Chapters demonstrated abilities to identify goals and objectives, create a workable plan of action, attain and evaluate results, and identify items learned and ways to improve. Chapter 1 discusses the FFA National Chapter Award program that…
Evaluating the Impact of Instructional Multimedia: Workable Techniques.
ERIC Educational Resources Information Center
Rathbun, Gail A.; Goodrum, David A.
A framework is proposed for the formative evaluation of multimedia. It describes techniques that have worked well in the evaluation of software development and gives examples of the use of evaluation results. The focus is primarily on the degree to which the instructional multimedia program supports the user's activities and tasks in the user's…
On the road: workable solutions to the problems of roads and highways
Mary M. Rowland
2004-01-01
Fourteen authors, ranging from transportation specialists to ecologists, have collaborated to write this very useful compendium describing the newly minted discipline of "road ecology." The authors state that road ecology "uses the science of ecology and landscape ecology to explore, understand, and address the interactions of roads and vehicles with...
An Analysis of the Insurance Sales Occupation.
ERIC Educational Resources Information Center
Moore, Gordon; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the insurance sales occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Eleven duties are broken down into a number…
ERIC Educational Resources Information Center
Clendening, Beverly
2004-01-01
Two molecular genetic projects were undertaken in Drosophila Molecular Genetics in partnership with teachers from High Schools. The students gained experience with DNA extraction through the project and 75% of produce data was usable for research, but the time put in to obtain success was excessive.
An Analysis of the Purchasing Occupation.
ERIC Educational Resources Information Center
Lustic, Gary; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the purchasing occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Fourteen duties are broken down into a number of…
Opening Doors: Students' Perspectives on Juggling Work, Family, and College.
ERIC Educational Resources Information Center
Matus-Grossman, Lisa; Gooden, Susan
Information gathered in focus groups of current, former, and potential students at six community colleges was used to explore institutional and personal access and retention issues faced by students seeking a workable balance of their college, work, and family responsibilities. The six community colleges were as follows: Cabrillo College (Aptos,…
An Analysis of the Lithographic Printing Occupation.
ERIC Educational Resources Information Center
Innis, Gene A.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the lithographic printing occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Nine duties are broken down into a…
Planting Yellow-Poplar--Where We Stand Today
T.E. Russell
1977-01-01
Yellow-poplar can be established on a wide variety of sites with bare-rooted seedlings and standard planting techniques. Many past plantings have performed poorly because substandard seedlings have been planted on unsuitable sites and competing vegetation has not been adequately controlled. Research over the past two decades, however, provides workable guides for site...
The Choctaw Home-Centered Family Education Demonstration Project. Final Report.
ERIC Educational Resources Information Center
Quigley, Patrick A.; And Others
The final report of the four-year (1972-1976) Choctaw Family Education Project identifies the major goal, "to demonstrate a workable early childhood model for rural reservation groups," and consists of an executive summary, a comprehensive report, and a personalized report. Objectives of the project, carried out in 6 Choctaw reservation…
An Analysis of the Residential Remodeling Occupation.
ERIC Educational Resources Information Center
Scruggs, Kenneth
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the residential remodeling occupation. The analysis only briefly covers the many areas of residential remodeling. The document opens with a brief introduction followed by a job description. The bulk of the…
An Analysis of the Carpentry Occupation.
ERIC Educational Resources Information Center
McKinney, Oral O.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the carpentry occupation. The analysis starts with the progress of a house from the first study of the blueprints to the laying out of the excavations and continuing step-by-step until the interior finish…
ERIC Educational Resources Information Center
Smith, Stacie Nicole; Fairman, David
2004-01-01
Conflict resolution education (CRE) grew out of several parallel efforts: integrating social justice into schools, concerns about safety and youth violence, and desires to enhance responsible citizenship. Today, CRE encompasses, or is a component of, a broad range of initiatives in schools: violence prevention programs, diversity and tolerance…
ERIC Educational Resources Information Center
Nist, Joan Stidham
Many prospective language arts teachers are unsure of what poetry really is. While it is impossible to present them with a definitive statement about the nature of poetry, they can be given a workable outline of the attributes of poetry to help them teach poetry to children. Rhythmic patterns can be emphasized to enhance children's enjoyment of…
An Analysis of the Information Receptionist Occupation.
ERIC Educational Resources Information Center
Sams, Helen C.; Snyder, Lois M.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the information receptionist occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Ten duties are broken down into a…
Workability of Mass Concrete. Report 2. Supplemental Proportioning Parameters.
1996-09-01
Information given in the report shall not be used in advertising or sales promotion to indicate endorsement of this product by U.S. Government. 14 Chapter 2... SALES PROMOTION TO INDICATE EITHER EXPLICITLY OR IMPLICITLY ENDORSEMENT OF THIS PRODUCT BY THE U.S. GOVERNMENT. FORM EDITION OF 1 SEP 84 IS OBSOLETE
An Analysis of the Industrial Sales Occupation.
ERIC Educational Resources Information Center
Kitzmiller, Charles C.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the industrial sales occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Eight duties are broken down into a number…
Target: Tomorrow. Second Career Planning for Military Retirees.
ERIC Educational Resources Information Center
Office of the Assistant Secretary of Defense for Manpower and Reserve Affairs (DOD), Washington, DC.
Intended for the career serviceman, this booklet attempts to provide the retiree with workable solutions to his own retirement situation and to assist him in resolving the transition between military and civilian life. The four steps the serviceman must take in approaching second career employment are given as follows: (1) review his experience,…
Teaching the Best Practice Way: Methods That Matter, K-12
ERIC Educational Resources Information Center
Daniels, Harvey; Bizar, Marilyn
2004-01-01
Everyone talks about "best practice" teaching--what does it actually look like in the classroom? How do working teachers translate complex curriculum standards into simple, workable classroom structures that embody exemplary instruction--and still let kids find joy in learning? In this book, the authors present seven basic teaching structures that…
NASA Astrophysics Data System (ADS)
Pavia, S.; Caro, S.
2007-07-01
Polarised-light (or petrographic) microscopy has been widely applied to heritage materials to assess composition and diagnose damage. However, instead, this paper focuses on the petrographic investigation of brick and mortar technologies for the production of quality repair materials compatible with their adjacent fabrics. Furthermore, the paper relates production technologies to the physical properties of the materials fabricated, and thus their final quality and durability. According to Cesare Brandi´s theory of compatibility (the 20th century architect on whose work modern conservation theory and practice are largely based) existing historic materials should be replaced with their equivalent. This paper demonstrates that polarised-light microscopy provides data on the origin and nature of raw materials, and processing parameters such as blending, mixing, firing, calcination and slaking, and how these relate to the quality of the final product. In addition, this paper highlights the importance of production technologies as these directly impact the physical properties of the materials fabricated and thus determine their final quality and durability. In this context, the paper investigates mortar calcination and slaking, two important operations in the manufacture of building limes that govern the reactivity, shrinkage and water retention of a lime binder which will impact mortar's properties such as workability, plasticity and carbonation speed, and these in turn will determine the ease of execution, durability and strength of a lime mortar. Petrographic analysis also provides evidence of ceramic technology including identification of local or foreign production and processing parameters such as sieving, blending, mixing and firing. A petrographic study of the ceramic matrix coupled to the diagnosis of mineral phases formed during firing allows to quantify sintering and vitrification and thus determine firing temperatures. Finally, certain features of the raw clay such as the grading and the amount and nature of the non-plastic material inform, not only on the raw material's origin, but also impact the physical properties of the ceramic ware.
Using TRIPS flexibilities to facilitate access to medicines
Owoeye, Olasupo
2013-01-01
Abstract The problem of how to mitigate the impact of pharmaceutical patents on the delivery of essential medicines to the world’s poor is as far from being resolved as it has ever been. Extensive academic commentary and policy debate have achieved little in terms of practical outcomes. Although international instruments are now in place allowing countries to enact legislation that permits the generic manufacture of patented pharmaceuticals, many countries have not yet enacted appropriate legislation and most of those that have yet to make use of it. One major problem is that the requirements of international instruments and implementing legislation are seen as being so stringent as to be unworkable. This paper calls for fresh attempts to enact workable legislation that fits within the prescribed requirements of international law without going beyond them. It argues that high-income nations should refocus on their moral obligation to enact appropriate legislative mechanisms and provide appropriate incentives for their use. Draft legislation currently being considered in Australia is used to illustrate how workable legislative frameworks can be developed. PMID:23825881
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kustas, Andrew B.; Susan, Donald F.; Johnson, Kyle L.
Processing of the low workability Fe-Co-1.5V (Hiperco® equivalent) alloy is demonstrated using the Laser Engineered Net Shaping (LENS) metals additive manufacturing technique. As an innovative and highly localized solidification process, LENS is shown to overcome workability issues that arise during conventional thermomechanical processing, enabling the production of bulk, near net-shape forms of the Fe-Co alloy. Bulk LENS structures appeared to be ductile with no significant macroscopic defects. Atomic ordering was evaluated and significantly reduced in as-built LENS specimens relative to an annealed condition, tailorable through selection of processing parameters. Fine equiaxed grain structures were observed in as-built specimens following solidification,more » which then evolved toward a highly heterogeneous bimodal grain structure after annealing. The microstructure evolution in Fe-Co is discussed in the context of classical solidification theory and selective grain boundary pinning processes. In conclusion, magnetic properties were also assessed and shown to fall within the extremes of conventionally processed Hiperco® alloys.« less
Kustas, Andrew B.; Susan, Donald F.; Johnson, Kyle L.; ...
2018-02-21
Processing of the low workability Fe-Co-1.5V (Hiperco® equivalent) alloy is demonstrated using the Laser Engineered Net Shaping (LENS) metals additive manufacturing technique. As an innovative and highly localized solidification process, LENS is shown to overcome workability issues that arise during conventional thermomechanical processing, enabling the production of bulk, near net-shape forms of the Fe-Co alloy. Bulk LENS structures appeared to be ductile with no significant macroscopic defects. Atomic ordering was evaluated and significantly reduced in as-built LENS specimens relative to an annealed condition, tailorable through selection of processing parameters. Fine equiaxed grain structures were observed in as-built specimens following solidification,more » which then evolved toward a highly heterogeneous bimodal grain structure after annealing. The microstructure evolution in Fe-Co is discussed in the context of classical solidification theory and selective grain boundary pinning processes. In conclusion, magnetic properties were also assessed and shown to fall within the extremes of conventionally processed Hiperco® alloys.« less
Evaluation of workability and strength of green concrete using waste steel scrap
NASA Astrophysics Data System (ADS)
Neeraja, D.; Arshad, Shaik Mohammed; Nawaz Nadaf, Alisha K.; Reddy, Mani Kumar
2017-11-01
This project works on the study of workability and mechanical properties of concrete using waste steel scrap from the lathe industry. Lathe industries produce waste steel scrap from the lathe machines. In this study, an attempt is made to use this waste in concrete, as accumulation of waste steel scrap cause disposal problem. Tests like compressive test, split tensile test, NDT test (UPV test) were conducted to determine the impact of steel scrap in concrete. The percentages of steel scrap considered in the study were 0%, 0.5%, 1%, 1.5%, and 2% respectively by volume of concrete, 7 day, 28 days test were conducted to find out strength of steel scrap concrete. It is observed that split tensile strength of steel scrap concrete is increased slightly. Split tensile strength of Steel scrap concrete is found to be maximum with volume fraction of 2.0% steel scrap. The steel scrap gives good result in split tensile strength of concrete. From the study concluded that steel scrap can be used in concrete to reduce brittleness of concrete to some extent.
NASA Technical Reports Server (NTRS)
Hou, Tan-Hung
2014-01-01
For the fabrication of resin matrix fiber reinforced composite laminates, a workable cure cycle (i.e., temperature and pressure profiles as a function of processing time) is needed and is critical for achieving void-free laminate consolidation. Design of such a cure cycle is not trivial, especially when dealing with reactive matrix resins. An empirical "trial and error" approach has been used as common practice in the composite industry. Such an approach is not only costly, but also ineffective at establishing the optimal processing conditions for a specific resin/fiber composite system. In this report, a rational "processing science" based approach is established, and a universal cure cycle design protocol is proposed. Following this protocol, a workable and optimal cure cycle can be readily and rationally designed for most reactive resin systems in a cost effective way. This design protocol has been validated through experimental studies of several reactive polyimide composites for a wide spectrum of usage that has been documented in the previous publications.
Workability and mental wellbeing among therapeutic prison officers.
Walker, E J; Jackson, C A; Egan, H H; Tonkin, M
2015-10-01
Previous research has examined how age and health can shape workability (WA). This study seeks to explore how a lack of WA (inability) may affect the health of the employee. To explore the effects of work inability on mental wellbeing among therapeutic prison officers. An anonymous cross-sectional study of prison officers conducted in a category B English prison using the Work Ability Index (WAI) and General Health Questionnaire-28 (GHQ). Fifty-seven officers (59%) participated and of those 95% achieved GHQ caseness. Officers with poorer WA reported significantly higher GHQ scores. Work inability for mental demands had significant associations with anxiety (β = -0.58, 95% CI -4.21 to -1.88, particularly sleep loss; Pearson's r = -0.66). Our findings present clear associations between poor WA and its impact upon mental wellbeing. The results of this study may help to focus on areas for intervention such as improving WA and promoting mental wellbeing. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Petro-state constraints on health policy: guidelines for workable reform in Venezuela.
Trujillo, Antonio J
2004-01-01
This article reviews the performance of the Venezuelan health care sector and suggests guidelines for workable health policy under difficult conditions. Two special circumstances constrain policy options. First, Venezuelans share a traditional value, solidarity, which includes a strong desire for equity. Reforms must comply with this norm to succeed. Second, foreign sales of state-controlled oil constitute the bulk of the government budget and the gross domestic product (GDP). Petroleum market fluctuations expose the country to extreme economic cycles. In response, policy making and stakeholders adopt a rentier attitude, focusing on preserving or enlarging entitlements to government oil monies. The side effects of this largesse include poor productivity, a weak private sector, a widespread sense of entitlement without accountability, and a crippled state which controls most of the available resources yet is unable to effectively tax, regulate, steer the economy, or pursue long-term policies. The health care sector shares these problems. As a result, Venezuela's health systems are fragmented, poorly coordinated, excessively centralized, inequitable, and ineffective. Policies to improve public health and public and private medical care must take into account these constraints.
Ahn, Tae-Ho; Kim, Hong-gi; Ryou, Jae-Suk
2016-01-01
This study focused on the development of a crack repair stick as a new repair method along with self-healing materials that can be used to easily repair the cracks in a concrete structure at the construction site. In developing this new repair technique, the self-healing efficiency of various cementitious materials was considered. Likewise, a crack repair stick was developed to apply to concrete structures with 0.3 mm or lower crack widths. The crack repair stick was made with different materials, such as cement, an expansive material (C12A7), a swelling material, and calcium carbonate, to endow it with a self-healing property. To verify the performance of the crack repair stick for concrete structures, two types of procedures (field experiment and field absorption test) were carried out. As a result of such procedures, it was concluded that the developed crack repair stick could be used on concrete structures to reduce repair expenses and for the improved workability, usability, and serviceability of such structures. On the other hand, to evaluate the self-healing performance of the crack repair stick, various tests were conducted, such as the relative dynamic modulus of elasticity test, the water tightness test, the water permeability test, observation via a microscope, and scanning electron microscope (SEM) analysis. From the results, it is found that water leakage can be prevented and that the durability of a concrete structure can be improved through self-healing. Also, it was verified that the cracks were perfectly closed after 28 days due to application of the crack repair stick. These results indicate the usability of the crack repair stick for concrete structures, and its self-healing efficiency. PMID:28773776
Food-resources and the influence of spatial pattern on feeding in the phoronid Phoronopsis viridis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ronan, T.E. Jr.
1978-06-01
In the intertidal zone of Bodega Harbor, California, the phoronid, Phoronopsis viridis, aggregates in clusters often composed of thousands of tightly aggregated individuals (up to 150,000/m/sup 2/). Within a dense cluster, there is a spacing problem for expansion of the lophophores. When nearest-neighbor distances are small, a stratification of feeding appendages is a workable solution to the spacing problem, allowing simultaneous expansion of clustered feeding appendages. Suspension-feeding specimens of Phoronopsis expand their lophophores and collect food items from the turbid near-bottom layers of water. Comparison of ingested items with material collected where the phoronids feed indicates a preference for smallmore » (<100 ..mu..m) organic encrusted mineral grains, floc aggregates, and fecal material, all resuspended from the depositional interface. Also taken to a lesser extent are plankton bloom species, such as diatoms and dinoflagellates. The fact that Phoronopsis forms dense assemblages in the intertidal zone has consequences when the community structure of sandflat areas is considered. Although it is probable that no single factor can explain aggregation in Phoronopsis, two possible factors, constituting strong selection pressures for cluster formation, are relative immunity from disturbance by large burrowing infauna and protection from predation by crawling predators.« less
Performance evaluation of high modulus asphalt concrete mixes
NASA Astrophysics Data System (ADS)
Haritonovs, V.; Tihonovs, J.; Zaumanis, M.
2016-04-01
Dolomite is one of the most available sedimentary rocks in the territory of Latvia. Dolomite quarries contain about 1000 million tons of this material. However, according to Latvian Road Specifications, this dolomite cannot be used for average and high intensity roads because of its low quality (mainly, LA index). Therefore, mostly imported magmatic rocks (granite, diabase, gabbro, basalt) or imported dolomite are used which makes asphalt expensive. However, practical experience shows that even with these high quality materials roads exhibit rutting, fatigue and thermal cracks. The aim of the research is to develop a high performance asphalt concrete for base and binder courses using only locally available aggregates. In order to achieve resistance against deformations at a high ambient temperature, a hard grade binder was used. Workability, fatigue and thermal cracking resistance, as well as sufficient water resistance is achieved by low porosity (3-5%) and higher binder content compared to traditional asphalt mixtures. The design of the asphalt includes a combination of empirical and performance based tests, which in laboratory circumstances allow simulating traffic and environmental loads. High performance AC 16 base asphalt concrete was created using local dolomite aggregate with polymer modified (PMB 10/40-65) and hard grade (B20/30) bitumen. The mixtures were specified based on fundamental properties in accordance to EN 13108-1 standard.
Xu, Hui; Gong, Weiliang; Syltebo, Larry; Lutze, Werner; Pegg, Ian L
2014-08-15
The binary furnace slag-metakaolin DuraLith geopolymer waste form, which has been considered as one of the candidate waste forms for immobilization of certain Hanford secondary wastes (HSW) from the vitrification of nuclear wastes at the Hanford Site, Washington, was extended to a ternary fly ash-furnace slag-metakaolin system to improve workability, reduce hydration heat, and evaluate high HSW waste loading. A concentrated HSW simulant, consisting of more than 20 chemicals with a sodium concentration of 5 mol/L, was employed to prepare the alkaline activating solution. Fly ash was incorporated at up to 60 wt% into the binder materials, whereas metakaolin was kept constant at 26 wt%. The fresh waste form pastes were subjected to isothermal calorimetry and setting time measurement, and the cured samples were further characterized by compressive strength and TCLP leach tests. This study has firstly established quantitative linear relationships between both initial and final setting times and hydration heat, which were never discovered in scientific literature for any cementitious waste form or geopolymeric material. The successful establishment of the correlations between setting times and hydration heat may make it possible to efficiently design and optimize cementitious waste forms and industrial wastes based geopolymers using limited testing results. Copyright © 2014 Elsevier B.V. All rights reserved.
Ash from a pulp mill boiler--characterisation and vitrification.
Ribeiro, Ana S M; Monteiro, Regina C C; Davim, Erika J R; Fernandes, M Helena V
2010-07-15
The physical, chemical and mineralogical characterisation of the ash resulting from a pulp mill boiler was performed in order to investigate the valorisation of this waste material through the production of added-value glassy materials. The ash had a particle size distribution in the range 0.06-53 microm, and a high amount of SiO(2) (approximately 82 wt%), which was present as quartz. To favour the vitrification of the ash and to obtain a melt with an adequate viscosity to cast into a mould, different amounts of Na(2)O were added to act as fluxing agent. A batch with 80 wt% waste load melted at 1350 degrees C resulting in a homogeneous transparent green-coloured glass with good workability. The characterisation of the produced glass by differential thermal analysis and dilatometry showed that this glass presents a stable thermal behaviour. Standard leaching tests revealed that the concentration of heavy metals in the leaching solution was lower than those allowed by the Normative. As a conclusion, by vitrification of batch compositions with adequate waste load and additive content it is possible to produce an ash-based glass that may be used in similar applications as a conventional silicate glass inclusively as a building ecomaterial. 2010 Elsevier B.V. All rights reserved.
Effect of unground oil palm ash as mixing ingredient towards properties of concrete
NASA Astrophysics Data System (ADS)
Sulaiman, M. A.; Muthusamy, K.; Mat Aris, S.; Rasid, M. H. Mohd; Paramasivam, R.; Othman, R.
2018-04-01
Malaysia being one of the world largest palm oil producers generates palm oil fuel ash (POFA), a by-product in increasing quantity. This material which usually disposed as solid waste causes pollution to the environment. Success in converting this waste material into benefitting product would reduce amount of waste disposed and contributes towards cleaner environment. This research explores the potential of unground oil palm ash being used as partial sand replacement in normal concrete production. Experimental work has been conducted to determine the workability, compressive strength and flexural strength of concrete when unground oil palm ash is added as partial sand replacement. A total of five mixes containing various percentage of oil palm ash, which are 0%, 5%, 10%, 15% and 20% have been prepared. All specimens were water cured until the testing date. The slump test, compressive strength test and flexural strength test was conducted. The findings show that mix produced using 10% of palm oil fuel ash exhibit higher compressive strength and flexural strength as compared to control specimen. Utilization of unground oil palm ash as partial sand replacement would be able to reduce dependency of construction industry on natural sand supply and also as one of the solution to reuse palm oil industry waste.
Communities, self-causation and the natural lottery.
Loewy, E H
1988-01-01
This paper examines the various notions of community, and of the 'natural lottery' as well as investigating the role that 'self-causation' plays in communal obligations. In examining community, two opposing views are juxtaposed: (1) the view that community consists merely of persons united by duties of refraining from harm one to another, resulting in autonomy based justice which makes freedom an absolute condition of mortality; and (2) a broader view which sees the concept of community as entailing obligations of beneficence, resulting in beneficence based justice and which, therefore, sees freedom as a value to be cautiously traded with other values. In examining the 'natural lottery' in the light of community, the various consequences of viewing the lottery in various ways and the impact that our view of community has on these consequences, is explored. A third option, the option that the 'natural lottery' as the cause of illness and health is a shaky concept, is offered. Self-causation of illness and its linkage to concepts of community and of the 'natural lottery' is then briefly examined. It is concluded that (1) community implies a social contract which, in order to be conceived in the first place, necessitates more than a minimalist ethic: to come about, a degree of beneficence inspiring trust is presupposed; (2) conceiving community narrowly is neither what we ordinarily do when we think of the term nor, for that matter, workable in our world.(ABSTRACT TRUNCATED AT 250 WORDS)
NASA Astrophysics Data System (ADS)
Maravelaki-Kalaitzaki, P.; Galanos, A.; Doganis, I.; Kallithrakas-Kontos, N.
2011-07-01
Mortars and plasters from the ancient aqueduct on the island of Naxos, Greece, were studied with regard to mineralogical and chemical composition, grain size distribution, raw materials and hydraulic properties, in order to assess their characteristics and design compatible repair mortars. The authentic materials contained lime, crushed-brick, siliceous and calcitic aggregates, in different proportions according to mortar type. Crushed-bricks fired at low temperatures and lightweight volcanic aggregates contained amorphous phases, which upon reaction with lime yielded hydraulic components capable of protecting the construction from the continuous presence of water. Hydraulic calcium silicate/aluminate hydrates, the proportions and the perfect packing of the raw materials, along with the diligent application justify the longevity and durability of the studied samples. The hydraulic properties of samples were pointed out through (a) the well-established CO2/H2O ratio derived from the thermogravimetric analysis and (b) by introducing two powerful indices issued from the chemical analysis, namely CaOhydr and soluble SiO2 hydr. These indices improved the clustering of hydraulic mortars and provided better correlation between mortars, plasters and their binders. By comparing grain size distribution and hydraulicity indices it was possible to distinguish among the construction phases. Based on this study, repair mortars were formulated by hydraulic lime, siliceous sand, calcareous and crushed-brick aggregates, with the optimal water content, ensuring optimum workability and compatible appearance with the authentic ones.
[Progress in bio-based polyamides].
Huang, Zhengqiang; Cui, Zhe; Zhang, Heming; Fu, Peng; Zhao, Qingxiang; Liu, Minying
2016-06-25
Bio-based polyamides are environment-friendly polymers. The precursors of bio-based polyamides come from bio-based materials such as castor oil, glucose and animal oil. Bio-based polyamides precursors include bio-based amino acids, bio-based lactams, bio-based diprotic acid and bio-based diamines. In this paper, we discussed the route of the precursors of bio-based polyamides that come from bio-based materials. We discussed the properties of bio-based polyamides. Bio-based PA11and bio-based PA1010 are well-known bio-based polyamides; we discussed the origin materials of the precursors, the route of manufacturing bio-based PA11 and PA1010, and their modifications status. The variety, classification and commercial production of bio-based polyamides were described in details, as well as bio-based polyamides development in China.
Making the Journey: Being and Becoming a Teacher of English Language Arts. Second Edition.
ERIC Educational Resources Information Center
Christenbury, Leila
This book takes a look at the realities of classroom life, offering specific suggestions for dealing effectively with today's students. More than a compendium of activities, the first edition of the book introduced educators to a philosophy of teaching illustrated and implemented by workable, realistic techniques. The second edition of the book…
Teamwork, Soft Skills, and Research Training.
Gibert, Anaïs; Tozer, Wade C; Westoby, Mark
2017-02-01
We provide a list of soft skills that are important for collaboration and teamwork, based on our own experience and from an opinion survey of team leaders. Each skill can be learned to some extent. We also outline workable short courses for graduate schools to strengthen teamwork and collaboration skills among research students. Copyright © 2016 Elsevier Ltd. All rights reserved.
An Analysis of the Real Estate Property Managing Occupation.
ERIC Educational Resources Information Center
Bryan, James E.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the real estate property manager occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Eleven duties are broken down…
An Analysis of the Payroll Clerking Occupation.
ERIC Educational Resources Information Center
Peal, Sharyn; Rose, Virginia
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the payroll clerk occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Ten duties are broken down into a number of…
ERIC Educational Resources Information Center
Educational Testing Service, Princeton, NJ.
Conference papers include: "The 'New Approach of the California State Colleges'" (Glenn S. Dumke); "Toward Institutional Goal-Consciousness" (Richard E. Peterson); "The Commission on Non-traditional Study - Who Needs It?" (John A. Valentine); "The Impact of Mandated Evaluation on Education" (Alexander I. Law); "A Workable Solution to the Demand…
ERIC Educational Resources Information Center
Darden, Edwin C., Ed.
This book is intended to help school leaders achieve a workable balance that allows schools to take advantage of the educational and administrative benefits of digital technologies while protecting the district from disruptive and expensive litigation. Chapter 1, "Student Learning and the Law of School Technology," focuses on developing policies…
Prisoners of Time: Implementing a Block Schedule in the High School.
ERIC Educational Resources Information Center
Mistretta, Gerald M.; Polansky, Harvey B.
1997-01-01
A committee comprised of six veteran teachers, the principal, and one parent initiated East Lyme (Connecticut) High School's search for a workable school schedule. The alternative-day block schedule featured semester and full-year course formats, 85-minute time blocks, a 45-minute lunch/club/activity period, and a closed campus. A survey found…
ERIC Educational Resources Information Center
Deroche, Timothy R.; Cooper, Bruce S.; Ouchi, William G.
2004-01-01
For more than a decade, education reformers have admired the achievements of the Edmonton Public Schools in Canada, and school districts across the United States have attempted to replicate Edmonton's success with school-site decision making. However, most districts have stopped short of implementing one policy that is central to Edmonton's…
A Workable Balance: Report to Congress on Family and Medical Leave Policies.
ERIC Educational Resources Information Center
Women's Bureau (DOL), Washington, DC.
The competing demands of the workplace and the home have intensified over the last 25 years as the nation has experienced dramatic social and economic changes affecting businesses, employees, and families. In 1993, Congress passed the Family and Medical Leave Act (FMLA) to provide a national policy that supports families in their efforts to strike…
Back to the Agora: Workable Solutions for Small Urban School Facilities. ERIC Digest.
ERIC Educational Resources Information Center
Lawrence, Barbara Kent
The ancient Athenian "agora" functioned as a marketplace for ideas and commerce and offered an ideal place for teaching and learning. This digest suggests adapting such a model to modern needs and describes successful small schools that have done so while reducing costs. Research shows that small schools offer many advantages for…
[Aerogenic risk factors and diagnosis of bauxite pneumoconiosis].
Peshkova, A O; Roslaia, N A; Roslyĭ, O F; Likhacheva, E I; Fedoruk, A A; Slyshkina, T V; Vagina, E R
2013-01-01
The research purpose is an estimation of influence of the bauxite dust on the state of the bronchopulmonary system of workers. It has been indicated that exposure of the poor fibrogenic dust while the process of the bauxite ore extraction, results in development of pnevmokoniosis characterized by substantial ventilatory and haemodynamic disorders limiting the workability of patients.
An Analysis of the Auto Body Repair Occupation.
ERIC Educational Resources Information Center
Stranke, Edward J.; Speck, Samuel R.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the auto body mechanic occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Eleven duties are broken down into a…
Open Learning in India: Evolution, Diversification and Reaching Out
ERIC Educational Resources Information Center
Sharma, Ramesh C.
2005-01-01
Distance education has a history of over four decades in India. There has been a vast growth in the number of learners who need education and thus also the corresponding channels of providing education. Due to the constraints of the traditional educational sector, open and distance learning has been found to be a workable alternative strategy in…
ERIC Educational Resources Information Center
Siegel, Peggy M.; Smoley, Eugene R., Jr.
The differences and similarities between education and the private sector are analyzed as they both engage in efforts to fundamentally restructure their operations. To bridge the cultural gap between business and education, a workable strategy that advances direct and sustained private-sector involvement in education reform is proposed. Part 1 of…
An Analysis of the Waste Water Treatment Maintenance Mechanic Occupation.
ERIC Educational Resources Information Center
Clark, Anthony B.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the waste water treatment mechanics occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Twelve duties are broken…
Times Change, but This Ten-Year-Old School Plan Remains Fresh and Functional.
ERIC Educational Resources Information Center
Rist, Marilee C.
1989-01-01
The 1979 passive solar design for Meadow Park Elementary School (Irvine, California) was not used until 1986. Architects had incorporated workable energy-saving features that would give a sizable return on the investment. They maximized use of natural light and used solar features (clerestory windows and interior courtyards) to reduce heat…
Policy Development of Quality Assurance: A Critical Perspective on Past and Future Issues.
ERIC Educational Resources Information Center
van der Westhuizen, L. J.
2000-01-01
Provides an overview of the initiatives and development of policies to establish a workable quality assurance system for institutions of higher education in South Africa in the last decade. Notes challenges such as the government's emphasis on programs of study and its requirement that quality assurance systems include institutional auditing,…
An Analysis of the Television and Radio Service Occupation.
ERIC Educational Resources Information Center
Pomeroy, James W.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the television and radio service occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Eight duties are broken down…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-01
... WHD to determine how those policies affect the work-life balance of workers and the productivity and work flow of employers. The study enables DOL to shape future regulatory options, craft interpretive... Family and Medical Leave. The final report on this survey, titled ``A Workable Balance: Report to...
W. Henry McNab; David L. Loftis
2013-01-01
Characteristic arborescent communities of mesophytic or xerophytic species have long been recognized as indicative of forest site quality in the Southern Appalachians, where soil moisture availability is the primary environmental variable affecting productivity. But, a workable quantitative system of site classification based on species composition is not available. We...
Unwritten: (Re)Imagining FE as Social Purpose Education
ERIC Educational Resources Information Center
Mycroft, Lou
2018-01-01
Drawing on stories from ten years of social purpose teacher education in the UK, this paper assumes that the future of further education is still unwritten. It illustrates complex and workable ideas via a theorised sketch of the fictional Bee Learning Programme, an imagined education setting of the future. The narrative that follows is designed to…
Experimental autoimmune hearing loss
Billings, Peter
2004-01-01
Understanding of autoimmune sensorineural hearing loss (ASNHL) has been hindered by the inaccessibility of the inner ear to biopsy and the lack of workable animal models. A report in this issue of the JCI describes a mouse model of CD4+ T cell–mediated ASNHL induced by immunization with peptides from the inner ear–specific proteins cochlin and β-tectorin. PMID:15085190
An Analysis of the Air Conditioning, Refrigerating and Heating Occupation.
ERIC Educational Resources Information Center
Frass, Melvin R.; Krause, Marvin
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the air conditioning, refrigerating, and heating occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Six duties are…
An Analysis of the Diesel Truck Mechanic Occupation.
ERIC Educational Resources Information Center
Kilo, Joseph L.
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the diesel truck mechanic occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Thirteen duties are broken down into a…
Motor Development and Movement Experiences for Young Children (3-7).
ERIC Educational Resources Information Center
Gallahue, David L.
This book's main objective is to help teachers and parents deal more knowledgeably and effectively with children through the medium of movement. The book has been written in such a manner that current theory, research, and practical application are merged into a workable whole. The first five chapters provide the reader with a basis of knowledge…
Classroom Software for the Information Age. Technical Report No. 23.
ERIC Educational Resources Information Center
Sheingold, Karen; And Others
Consumers and producers of educational software must make decisions about what kind of software to buy and create. Both groups must base these decisions on criteria that consider what it is important to learn in our technological era, what is workable, and what is currently practical and cost-effective. Five criteria that are central to these…
Hang in there! Quick takes on Y2K.
Lewis, A G; Weingart, V S
1998-11-01
Cliffhangers in movies are great fun. But not in real life. Think Y2K. If you haven't scripted a way to beat the millennium bug, there are workable solutions that can be created in six months. Here's how to begin production: Prioritize activities, expenditures and resources, and apply them to the most vital problems first.
An Analysis of the Real Estate Occupation.
ERIC Educational Resources Information Center
Harestad, Clifford E.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the real estate occupation. It represents an accounting of what must be done, but not how the entire cycle of a residential sale is completed through the services of a real estate person and the…
ERIC Educational Resources Information Center
Kaplan, Linda; And Others
This four-part report describes Directions for Success, a school-college collaborative project between Middlesex Community College and 15 area school districts designed to provide learning disabled students and their parents with career assessment services and access to information which will enable them to make workable, long-range career plans.…
Proposed Multiconjugate Adaptive Optics Experiment at Lick Observatory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bauman, B J; Gavel, D T; Flath, L M
2001-08-15
While the theory behind design of multiconjugate adaptive optics (MCAO) systems is growing, there is still a paucity of experience building and testing such instruments. We propose using the Lick adaptive optics (AO) system as a basis for demonstrating the feasibility/workability of MCAO systems, testing underlying assumptions, and experimenting with different approaches to solving MCAO system issues.
Non-Formal Vocational Education in Uganda: Practical Empowerment through a Workable Alternative
ERIC Educational Resources Information Center
Blaak, Marit; Openjuru, George L.; Zeelen, Jacques
2013-01-01
This article reflects on the potential of non-formal vocational education in Uganda to improve the quality of life of those excluded from formal education. Based on an exploration of humanizing development theorists Sen, Freire and Nyerere, together with two case studies, practical empowerment is described as a desirable outcome of education for…
PLUTONIUM-URANIUM-TITANIUM ALLOYS
Coffinberry, A.S.
1959-07-28
A plutonium-uranium alloy suitable for use as the fuel element in a fast breeder reactor is described. The alloy contains from 15 to 60 at.% titanium with the remainder uranium and plutonium in a specific ratio, thereby limiting the undesirable zeta phase and rendering the alloy relatively resistant to corrosion and giving it the essential characteristic of good mechanical workability.
Military Power in a Democratic Society. Teacher and Student Manuals.
ERIC Educational Resources Information Center
Zarlengo, F. John
This unit focuses on the classic problem of the place of military power in a democratic society. Early sections examine the relationship between civil and military authority as developed in colonial America and written into the Constitution. The second half of the unit invites consideration of the relevance and workability of the earlier tradition…
The Pros and Cons of Individualized Programmed Instruction for Indian Students. A Position Paper....
ERIC Educational Resources Information Center
Corcoran, Bert W.
Based on observations and experiences in a Title III (Elementary and Secondary Education Act) project to individualize instruction in the ungraded Rocky Boy Elementary School (grades 1-6, Rocky Boy Indian Reservation, Box Elder, Montana), this position paper considers the problem of finding a suitable or workable curriculum and classroom climate…
Marvelous Signals: The Usefulness of the In-Class Essay.
ERIC Educational Resources Information Center
Crafton, John Micheal
Based on his experience of being trained in a process-centered pedagogy and of working in a product-centered program, a writing instructor discovers that the in-class essay is not only a useful or workable part of a regressive curriculum, but that it is effective and necessary for any progressive process orientation as well. Pragmatic, ethical,…
ERIC Educational Resources Information Center
Haas, Tanni
Given the increasing influence of public journalism on the daily routines of newspapers across the United States, students need to be taught how to find a workable balance between consulting and reporting on conventional information sources and consulting and reporting on the perspectives provided by ordinary citizens. This paper discusses ways in…
An Analysis of the Dental Assisting Occupation.
ERIC Educational Resources Information Center
Hough, Sharon L.; And Others
The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the dental assistant occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Six duties are broken down into a number of…
ERIC Educational Resources Information Center
Research and Planning Group for California Community Colleges (RP Group), 2005
2005-01-01
This report to the Legislature and Governor provides recommendations on the design of a workable structure for the annual evaluation of district-level performance for California Community College districts. Under contract with the California Community Colleges Chancellor's Office, a six-member panel of the Research and Planning Group for…
Making It Rich and Personal: Crafting an Institutional Personal Learning Environment
ERIC Educational Resources Information Center
White, Su; Davis, Hugh C.
2011-01-01
Many of the communities interested in learning and teaching technologies within higher education now accept the view that a conception of personal learning environments provides the most realistic and workable perspective of learners' interactions with and use of technology. This view may not be reflected in the behaviour of those parts of a…
ERIC Educational Resources Information Center
Myer, Teresa A.
This study examined four teacher in-service environmental education programs to: (1) suggest a workable evaluative model for such programs; (2) assess their content with respect to stated activities and objectives; and (3) determine whether or not the experiences correlated with changes in selected teaching behaviors. The research design included…
ERIC Educational Resources Information Center
Ulrich, Mary Eileen
2016-01-01
How does higher education contribute to finding workable and lasting solutions to complex social issues that face communities globally today? How does higher education contribute to global sustainable development goals? The scholarship of engagement encourages faculty, scholars, and students to work together with communities on solutions to…
Achieving Youth Employment and National Security in Nigeria: TVET Imperatives
ERIC Educational Resources Information Center
Ogbuanya, T. C.; Ofonmbuk, Michael
2015-01-01
The rate of unemployment in Nigeria is alarming and could promote social vices some of which are kidnapping, armed robbery, child trafficking, Cultism, Drug peddling and ritual killing. These social vices could in no small measure constitute a threat to national security as a matter of fact. Therefore, the development of a workable Technical and…
Teaching Content Material through Reader's Theater
ERIC Educational Resources Information Center
Forney, Melissa
2013-01-01
When it comes to content area material, much of what students read and learn is predicated on information they have read before and are supposed to remember. Teachers often use silent reading and round robin reading as preferred reading methods to help students learn content area material. The objective of this study was to test reader's theater…
Use of Biochar from the Pyrolysis of Waste Organic Material as a Soil Amendment
USDA-ARS?s Scientific Manuscript database
Biochar is a charcoal-like material produced by the thermochemical pyrolysis of biomass materials. It is being considered as a potentially significant means of storing carbon for long periods to mitigate greenhouse gases. Much of the interest comes from studies of Amazonian soils that appear to have...
New Comparative Measures of Income, Material Deprivation, and Well-Being
ERIC Educational Resources Information Center
Smeeding, Timothy M.
2009-01-01
Most societies, rich and poor, seek to measure progress in reducing poverty and need, as indicated by material deprivation or social exclusion. The yardsticks used to assess progress and policy impact mainly include income-based poverty, but broader measures of poverty based on consumption, wealth, and material deprivation are also now coming into…
How much improvement in thermoelectric performance can come from reducing thermal conductivity?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gaultois, Michael W., E-mail: mgaultois@mrl.ucsb.edu; Sparks, Taylor D., E-mail: sparks@eng.utah.edu
Large improvements in the performance of thermoelectric materials have come from designing materials with reduced thermal conductivity. Yet as the thermal conductivity of some materials now approaches their amorphous limit, it is unclear if microstructure engineering can further improve thermoelectric performance in these cases. In this contribution, we use large data sets to examine 300 compositions in 11 families of thermoelectric materials and present a type of plot that quickly reveals the maximum possible zT that can be achieved by reducing the thermal conductivity. This plot allows researchers to quickly distinguish materials where the thermal conductivity has been optimized frommore » those where improvement can be made. Moreover, through these large data sets we examine structure-property relationships to identify methods that decrease thermal conductivity and improve thermoelectric performance. We validate, with the data, that increasing (i) the volume of a unit cell and/or (ii) the number of atoms in the unit cell decreases the thermal conductivity of many classes of materials, without changing the electrical resistivity.« less
Coming Together, Coming Apart. Black Settlers in Rural Wisconsin. Teachers' Manual.
ERIC Educational Resources Information Center
Cooper, Zachary L.; Tari, Emilie
This teaching manual, designed to accompany a Wisconsin State television series, focuses on that State's rural black families and their lives in the 19th and early 20th centuries. The manual begins with notes on its organization and use, as well as major objectives for students who study the material presented. Four units follow. Unit 1 explores…
Lendrum, J.
1980-01-01
Alternatives to conventional skin flap cover for limb wounds extend both the number and type of defects which can now be closed with reconstruction of both form and function for patients who might otherwise come to amputation. The old adage that where a sinus leads to dead or foreign material it can only be closed after removal of that dead or foreign material is no longer true. The number of patients coming to above-knee amputation after prosthetic replacement of the knee joint could be reduced by muscle flap cover of exposed arthroplasty prostheses. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:7377695
Assessments of low emission asphalt mixtures produced using combinations of foaming agents
NASA Astrophysics Data System (ADS)
Mohd Hasan, Mohd Rosli
The asphalt foaming techniques have been used over the last couple of decades as an alternative to the traditional method of preparing asphalt mixtures. Based on positive feedback from the industry, this study was initiated to explore and evaluate the performance of the Warm Mix Asphalt (WMA) mixture produced through a foaming process using physical and chemical foaming agents, which are ethanol and sodium bicarbonate (NaHCO3), respectively. The success of this project may lead to new theories and provide an environmentally friendly technique to produce asphalt mixtures. This may advance the understanding of the foaming process and improve the performance of WMA to support sustainable development. Theoretically, ethanol can function in the same manner as water but requires less energy to foam due to its lower boiling point, 78°C. During the asphalt foaming process, numerous bubbles were generated by the vaporized ethanol, which significantly increased the volume of the asphalt binder, hence the coating potential of aggregates improves. The sodium bicarbonate was incorporated to enhance the quantity of bubbles and its stability. Therefore, understanding foaming agents, their solubility, chemical reactions, chemical function groups and rheological properties of the foamed binder are essential to help control the foam structure and final properties of the foamed WMA mixture. In order to understand the overall performance of newly developed foaming WMA, this material was evaluated for moisture susceptibility, rutting potential, and resistance to fracture and thermal cracking. The coatability, workability and compactability of foamed asphalt mixtures during production were also evaluated. Based on the results, it was found that the newly proposed foaming WMA has high potential to promote sustainable development by lowering the energy consumption and impacts on the environment. The ethanol is efficient in lowering the viscosity of asphalt binders, enhancing the workability, and having a higher expulsion rate from the foamed binder compared to water as a foaming agent. The addition of foaming agents to the asphalt binder has also lowered the activation energy of the asphalt binder, which has high potential in lowering the energy demand during production processes. The foamed WMA mixture prepared at 100°C was found to have behavior comparable with the control Hot Mix Asphalt (HMA) prepared at 155°C in terms of coatability, workability and compactability. Based on the mixture performance tests, the foamed WMA has a comparable or better performance than the HMA in terms of resistance to moisture damage, permanent deformation, fracture cracking and thermal cracking. The application of nano-hydrated lime is efficient in enhancing the aggregate coatability and improving the bearing capacity of asphalt pavement to lower the rutting potential and moisture susceptibility of foamed WMA mixtures. Limitations for each of the related parameters are also reported in this dissertation for the lab production of foamed WMA mixtures using ethanol and NaHCO 3 as foaming agents. The specified values were made based on the binder test, service characteristics and performance of foamed WMA mixtures in order to yield a comparable or better performance than the control HMA. Field validations should be carried out to understand the overall performance and durability of the proposed foaming WMA.
The Materiality of Digital Collections: Theoretical and Historical Perspectives
ERIC Educational Resources Information Center
Manoff, Marlene
2006-01-01
Digital and textual objects are coming under a new kind of scrutiny as scholars are becoming more interested in physical artifacts and their relation to their social and cultural environment. This study of material culture suggests a need to explore the nature of digital materiality, as well as the broader historical context in which electronic…
Christopher E. Langum; Vikram Yadama; Eini C. Lowell
2009-01-01
Diversity in land management objectives has led to changes in the character of raw material available to the forest products industries in the US Pacific Northwest. Increasing numbers of logs from small-diameter trees, both plantation grown and those from suppressed or young stands, now constitute a large proportion of logs coming into the mill yard. Wood coming from...
ERIC Educational Resources Information Center
Vazquez, Jose J.; Chiang, Eric P.
2016-01-01
Motivating students to come prepared to class is often a futile exercise. The consequences are magnified as more instructors adopt the flipped classroom teaching model, in which students are expected to come to class with some knowledge of the material. This paper analyzed the implementation of a pedagogical tool that addresses this problem:…
Tactile-Sensing Based on Flexible PVDF Nanofibers via Electrospinning: A Review
Wang, Xiaomei; Sun, Fazhe; Yin, Guangchao; Wang, Yuting; Liu, Bo
2018-01-01
The flexible tactile sensor has attracted widespread attention because of its great flexibility, high sensitivity, and large workable range. It can be integrated into clothing, electronic skin, or mounted on to human skin. Various nanostructured materials and nanocomposites with high flexibility and electrical performance have been widely utilized as functional materials in flexible tactile sensors. Polymer nanomaterials, representing the most promising materials, especially polyvinylidene fluoride (PVDF), PVDF co-polymer and their nanocomposites with ultra-sensitivity, high deformability, outstanding chemical resistance, high thermal stability and low permittivity, can meet the flexibility requirements for dynamic tactile sensing in wearable electronics. Electrospinning has been recognized as an excellent straightforward and versatile technique for preparing nanofiber materials. This review will present a brief overview of the recent advances in PVDF nanofibers by electrospinning for flexible tactile sensor applications. PVDF, PVDF co-polymers and their nanocomposites have been successfully formed as ultrafine nanofibers, even as randomly oriented PVDF nanofibers by electrospinning. These nanofibers used as the functional layers in flexible tactile sensors have been reviewed briefly in this paper. The β-phase content, which is the strongest polar moment contributing to piezoelectric properties among all the crystalline phases of PVDF, can be improved by adjusting the technical parameters in electrospun PVDF process. The piezoelectric properties and the sensibility for the pressure sensor are improved greatly when the PVDF fibers become more oriented. The tactile performance of PVDF composite nanofibers can be further promoted by doping with nanofillers and nanoclay. Electrospun P(VDF-TrFE) nanofiber mats used for the 3D pressure sensor achieved excellent sensitivity, even at 0.1 Pa. The most significant enhancement is that the aligned electrospun core-shell P(VDF-TrFE) nanofibers exhibited almost 40 times higher sensitivity than that of pressure sensor based on thin-film PVDF. PMID:29364175
ERIC Educational Resources Information Center
Collins, Terence; Price, Lynda
As part of a three-year federally funded research program intended to shed light on the writing processes of learning disabled college-aged writers (with special emphasis on the use of technology in creating workable mainstreamed curricula), this paper records in an interview format the responses of students to the program, including word…
Construction of a microscopic agent-based model for firms' dynamics
NASA Astrophysics Data System (ADS)
Iyetomi, Hiroshi; Aoyama, Hideaki; Fujiwara, Yoshi; Ikeda, Yuichi; Kaizoji, Taisei; Soma, Wataru
2005-07-01
A workable microscopic model for firms' dynamics has been constructed. The model consists of firm agents and a bank agent dynamics of which are described by balance sheets. The size distribution of firms and the temporal evolution of the bank show critical dependence on whether or not firms use perfect information on their financial conditions to draw up next production plans.
FABRICATION OF URANIUM-ALUMINUM ALLOYS
Saller, H.A.
1959-12-15
A process is presented for producing a workable article of a uranium- aluminum alloy in which the uranium content is between 14 and 70% by weight; aluminum powder and powdered UAl/sub 2/, UAl/sub 3/, UAl/sub 5/, or UBe/sub 9/ are mixed, and the mixture is compressed into the shape desired and sintered at between 450 and 600 deg C.
ERIC Educational Resources Information Center
Guhse, David
This report presents case studies illustrating successful public-private financing of school construction. The efforts occurred in Canada, Florida, South Carolina, New York, the District of Columbia, and Texas. The case studies are offered to encourage policy makers in Virginia to consider such an approach to meet the state's school construction…
Shan Gao; Xiping Wang; Lihai Wang; R. Bruce. Allison
2012-01-01
The goals of this study were to investigate the effect of environment temperature on acoustic velocity of standing trees and green logs and to develop workable models for compensating temperature differences as acoustic measurements are performed in different climates and seasons. The objective of Part 1 was to investigate interactive effects of temperature and...
METHOD OF SUPPRESSING UAl$sub 4$ FORMATION IN U-Al ALLOYS
Picklesimer, M.L.; Thurber, W.C.
1960-08-23
A method is given for suppressing the formation of UAl/sub 4/ in uranium- - aluminum alloys, thereby rendering these alloys more easily workable. The method comprises incorporating in the base alloy a Group Four element selected from the group consisting of Si, Ti, Ge, Zr, and Sn, the addition preferably being within the range of 0.5to20at.%.
ERIC Educational Resources Information Center
LaGuardia, Cheryl, Ed.; Mitchell, Barbara A., Ed.
Adapting today's libraries to better serve tomorrow's needs challenges even the most forward-thinking library staff. This book offers practical, workable solutions from several authorities in the industry. Fifty-five conference papers are included and divided into the following subject areas: "Technology and the Network: Daimons or Demons?";…
Utilization of the Eastern Hardwood Resource by the Hardwood Sawmilling Industry
William Luppold; John Baumgras; John Baumgras
2001-01-01
The eastern hardwood resource contains numerous species that differ in grain, color, texture, and workability. Because the value of hardwoods is derived from appearance, these variations in physical attributes can cause the price for identical grades of hardwood lumber to vary by as much as 600% between species. As a result, there is incentive for primary processors to...
ERIC Educational Resources Information Center
Bloxham, Sue
2012-01-01
This article considers the failure of theory to provide a workable model for academic standards in use. Examining the contrast between theoretical perspectives, it argues that there are four dimensions for which the academy has failed to provide an adequate theoretical account of standards: documented or tacit knowledge of standards; norm or…
Soviet Maintenance Training and the Technological Imperative.
1980-06-01
competition arid obligations, the rise of innovators, inventors arid rationalizers , as well as thle irmportance placed on technolo2 ical awareness are...the Communist Party in the training process, socialist competition and obligations, the use of innovators, inventors and rationalizers , as well as the...current military-technical environment . The paper concludes that the Soviets have a workable and relatively effective system for peacetime maintenance
ERIC Educational Resources Information Center
Friedman, Brenda G.; And Others
The manual is intended to help students with language learning disabilities master the academic task of research paper writing. A seven-step procedure is advocated for students and their tutors: (1) select a workable topic, then limit and focus it; (2) use library references to identify sources from which to prepare a working bibliography; (3)…
A Special Section on International Education--What We Can Learn from Russia's Schools
ERIC Educational Resources Information Center
Post, Becky
2005-01-01
Russia's educational system has been successful in producing graduates who excel in mathematics, the sciences, and foreign languages, but these are not the only areas that we might look to as models. Russian and American cultures and educational practices differ in significant ways, and not all of the practices described here would be workable in…
ERIC Educational Resources Information Center
Lloyd, Jennifer E. V.; Zumbo, Bruno D.; Siegel, Linda S.
2009-01-01
In the past 20 years, the analysis of individual change has become a key focus in educational research. There are several parametric analyses that centre upon quantifying change. Some researchers state that such analyses should only occur if the measure itself remains completely unchanged across waves, arguing that it is not possible to link or…
1991-10-28
Markets [TIGAI XINXI No 14] ......................................... 28 Cotton Purchases Increased To Stabilize Supply [CHINA DAILY 14 Oct...workable measures, and they have received in markets . After 10 years of reform, an over- begun to take action in accordance with the separate whelming...lack the boldness Village and at Taihuangshan Village in Ganquan, and needed to develop markets . In many things they do, they the very large scale on
Managers Confront Competing Practical, Legal, and Ethical Claims: A Comprehensive Teaching Case
ERIC Educational Resources Information Center
McAdams, Tony
2009-01-01
Law classes help reveal the successes of the American legal system. Students observe that the law is honorable, workable, and effective. At the same time, law classes offer the opportunity to look at those situations where the legal system sometimes struggles to achieve its justice goals. Students certainly need to learn that lesson, but they also…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-07
... analysis of private sector FMLA policies allows WHD to determine how those policies affect the work-life balance of workers and the productivity and work flow of employers. The study enables DOL to shape future... Commission on Family and Medical Leave. The final report on this survey, titled ``A Workable Balance: Report...
It Is Not Just about the Schedule: Key Factors in Effective Reference Desk Scheduling and Management
ERIC Educational Resources Information Center
Sciammarella, Susan; Fernandes, Maria Isabel; McKay, Devin
2008-01-01
Reference desk scheduling is one of the most challenging tasks in the organizational structure of an academic library. The ability to turn this challenge into a workable and effective function lies with the scheduler and indirectly the cooperation of all librarians scheduled for reference desk service. It is the scheduler's sensitivity to such…
A Framework for Action To Make Private Housing Lead-Safe: A Proposal To Focus National Attention.
ERIC Educational Resources Information Center
Alliance to End Childhood Lead Poisoning, Washington, DC.
This framework sets forth detailed proposals that are crucial to eliminating the epidemic of childhood lead poisoning in the United States. Private housing units can and must be made lead-safe, and this framework is designed to achieve that goal through specific requirements for property owners, a workable schedule, and mechanisms that reinforce…
Your Family Land: Legacy or Memory? An Introduction to the Family Land Protection Process
USDA Forest Service, Northeastern Area, State and Private Forestry
2008-01-01
If you have this perspective, protecting your land from development is a task you certainly can accomplish. Virtually every situation is workable and every problem can be solved. It does require some planning and decisionmaking; however, so the sooner you start the better. Experience has shown that the number one obstacle to the protection of family land...
Systems in Tension: Perceptions of Business and Education in Partnership
ERIC Educational Resources Information Center
Despres, Blane Rolland
2003-01-01
The aim of this research project has been to map the range of perceptions of a sample of people concerning business in partnership with education. From the range of perceptions held by the participants in this dissertation, we can conclude that partnering is not a simple matter of two parties agreeing to some workable union between them for mutual…
Teaching French Vocabulary to English Speaking Students. A Comprehensive and Eclectic Approach.
ERIC Educational Resources Information Center
Howlett, Frederick G.
The greatest need of language teachers today is a workable approach to teaching vocabulary. This is essential if students are to be enabled to achieve communicative competence, that is, to make a transfer from the textbook to the real world of French, as reflected in the French media. An effective and comprehensive approach to teaching vocabulary…
Life Span as the Measure of Performance and Learning in a Business Gaming Simulation
ERIC Educational Resources Information Center
Thavikulwat, Precha
2012-01-01
This study applies the learning curve method of measuring learning to participants of a computer-assisted business gaming simulation that includes a multiple-life-cycle feature. The study involved 249 participants. It verified the workability of the feature and estimated the participants' rate of learning at 17.4% for every doubling of experience.…
School Discipline: Best Practices for Administrators. Second Edition
ERIC Educational Resources Information Center
Rosen, Louis
2005-01-01
In this book, the author offers the best ideas and most workable discipline practices from more than 1,000 school leaders. The book is loaded with updates and gives administrators all the tools they need to create a safe environment, from dealing effectively with the 5% of students who take up 90% of their time, to creating a positive public image…
ERIC Educational Resources Information Center
Home Builders Inst., Washington, DC.
This guide presents a focused, structured method of facilitating ex-offender employment. Section 1 takes classic marketing techniques and adapts them to the needs of the particular situation, placing ex-offenders in meaningful employment. The set of specific requirements for creating a workable marketing plan is condensed to six basic steps that…
Advanced Solar Observatory (ASO) accommodations requirements study
NASA Technical Reports Server (NTRS)
1989-01-01
Results of an accommodations analysis for the Advanced Solar Observatory on Space Station Freedom are reported. Concepts for the High Resolution Telescope Cluster, Pinhole/Occulter Facility, and High Energy Cluster were developed which can be accommodated on Space Station Freedom. It is shown that workable accommodations concepts are possible. Areas of emphasis for the next stage of engineering development are identified.
Measurement of Workability of Fresh Concrete Using a Mixing Truck
Amziane, Sofiane; Ferraris, Chiara F.; Koehler, Eric P.
2005-01-01
The main objective of this study is to evaluate the workability of fresh portland cement concrete while it is still in the mixing truck by determining fundamental rheological parameters (plastic viscosity and yield stress). Nine concrete mixtures with different values of yield stress and plastic viscosity were tested in a concrete truck. The measurements made with the truck were based on the typical method of determining the flow behavior in a traditional fluid rheometer; that is, the shear rate in the mixing truck was swept from high to low by varying the rotation speed of the drum. The results of these experiments are discussed and compared with data provided by the ICAR rheometer, a portable rheometer designed for measuring concrete rheology. The test results indicate that the mixing truck equipment is sufficiently sensitive to detect differences in yield stress, slump, and plastic viscosity. However, the plastic viscosity determined by the truck measurement did not correlate with plastic viscosity as measured by the ICAR rheometer, while the yield stress determined by the truck measurement did correlate well with the measured slump and the ICAR rheometer results Suggestions are given on how to improve the mixing truck for better use as a rheometer. PMID:27308103
VALUE: A trans-disciplinary research project - and some challenges in its implementation
NASA Astrophysics Data System (ADS)
Huebener, Heike
2013-04-01
The EU-COST-action VALUE ("Validating and Integrating Downscaling Methods for Climate Change Research") is composed as a trans-disciplinary network activity, meaning that stakeholders and end-users not only from different scientific disciplines (i.e. inter-disciplinary research) but also from outside science are included in the design, planning and progress of the project. This gives the optimal chance to produce really workable project results for the intended end-users. However, some considerable challenges lie this way. These challenges start with identifying and motivating the target-stakeholders, they cover communication in different user-specific languages and reach as far as the question of the freedom of research when under the prompting of politics or economy. We will cover only some of the mentioned challenges; focusing on the identification of the target-stakeholders or end-users, their motivation to participate in the project and on some typical problems arising in this constellation. First experiences from the project will be presented. The aim of the presentation is to instigate discussion on developing workable project structures for trans-disciplinary research, as this will become more and more relevant in future research funding.
NASA Astrophysics Data System (ADS)
Galkina, N. V.; Nosova, Y. A.; Balyakin, A. V.
2018-03-01
This research is relevant as it tries to improve the mechanical and service performance of the Ti–6Al–4V titanium alloy obtained by selective laser sintering. For that purpose, sintered samples were annealed at 750 and 850°C for an hour. Sintered and annealed samples were tested for hardness, workability and microstructure. It was found that incomplete annealing of selectively laser-sintered Ti–6Al–4V samples results in an insignificant reduction in hardness and ductility. Sintered and incompletely annealed samples had a hardness of 32..33 HRC, which is lower than the value of annealed parts specified in standards. Complete annealing at temperature 850°C reduces the hardness to 25 HRC and ductility by 15...20%. Incomplete annealing lowers the ductility factor from 0.08 to 0.06. Complete annealing lowers that value to 0.025. Complete annealing probably results in the embrittlement of sintered samples, perhaps due to their oxidation and hydrogenation in the air. Optical metallography showed lateral fractures in both sintered and annealed samples, which might be the reason why they had lower hardness and ductility.
Development of 6.1 A Materials for IR Applications
2011-12-01
growth and electrical characterization. Additionally, we would like to thank Dr. Sudhir Trivedi of Brimrose Corporation for his assistance with etchant...ARL from Brimrose Corp with extensive 7 knowledge of chemistry related to materials science, we have come across a promising solution that reveals
Code of Federal Regulations, 2011 CFR
2011-07-01
... control devices, friable asbestos waste material, and bags or other similar packaging contaminated with... in the Act and in subpart A of this part. Active waste disposal site means any disposal site other... release of particulates. If visible emissions are observed coming from asbestos-containing material, then...
Replacing noble metals with alternative materials in plasmonics and metamaterials: how good an idea?
NASA Astrophysics Data System (ADS)
Khurgin, Jacob B.
2017-03-01
Noble metals that currently dominate the fields of plasmonics and metamaterials suffer from large ohmic losses. Some of the new plasmonic materials, such as doped oxides and nitrides, have smaller material loss, and using them in place of metals carries the promise of reduced-loss plasmonic and metamaterial structures, with sharper resonances and higher field concentrations. This promise is put to a rigorous analytical test in this work, which reveals that having low material loss is not sufficient to have reduced modal loss in plasmonic structures. To reduce the modal loss, it is absolutely necessary for the plasma frequency to be significantly higher than the operational frequency. Using examples of nanoparticle plasmons and gap plasmons one comes to the conclusion that, even in the mid-infrared spectrum, metals continue to hold an advantage over alternative media when it comes to propagation distances and field enhancements. Of course, the new materials still have an application niche where high absorption loss is beneficial, e.g. in medicine and thermal photovoltaics. This article is part of the themed issue 'New horizons for nanophotonics'.
NASA Technical Reports Server (NTRS)
Sharpe, E. L.; Jackson, L. R.
1975-01-01
A model which consisted of a hot structure and a nonintegral tank protected by a carbon dioxide frost thermal protection system was tested under the following conditions: (1) room temperature loading and (2) heating and loading corresponding to the Mach 8 flight of an air-breathing launch vehicle. In the simulated flight tests, liquid nitrogen inside the tank was withdrawn at the rate fuel would be consumed. Prior to each simulated flight test, carbon dioxide was cryodeposited in the insulation surrounding the tank; during the tests, subliming CO2 frost absorbed heat and provided a purge gas for the space between the tank and the structure. A method of flame spraying the joints between panels with a nickel-aluminum material was developed to prevent excessive leakage of the purge gas through the outer structure. The tests indicated that the hot structure (with a joint repaired by riveting), the nonintegral tank and suspension system, and the carbon dioxide frost thermal protection system provide a workable concept with predictable performance.
Clinical informatics in undergraduate teaching of health informatics.
Pantazi, Stefan V; Pantazi, Felicia; Daly, Karen
2011-01-01
We are reporting on a recent experience with Health Informatics (HI) teaching at undergraduate degree level to an audience of HI and Pharmacy students. The important insight is that effective teaching of clinical informatics must involve highly interactive, applied components in addition to the traditional theoretical material. This is in agreement with general literature underlining the importance of simulations and role playing in teaching and is well supported by our student evaluation results. However, the viability and sustainability of such approaches to teaching hinges on significant course preparation efforts. These efforts consist of time-consuming investigations of informatics technologies, applications and systems followed by the implementation of workable solutions to a wide range of technical problems. In effect, this approach to course development is an involved process that relies on a special form of applied research whose technical complexity could explain the dearth of published reports on similar approaches in HI education. Despite its difficulties, we argue that this approach can be used to set a baseline for clinical informatics training at undergraduate level and that its implications for HI education in Canada are of importance.
Effect of chemical admixtures on properties of high-calcium fly ash geopolymer
NASA Astrophysics Data System (ADS)
Rattanasak, Ubolluk; Pankhet, Kanokwan; Chindaprasirt, Prinya
2011-06-01
Owing to the high viscosity of sodium silicate solution, fly ash geopolymer has the problems of low workability and rapid setting time. Therefore, the effect of chemical admixtures on the properties of fly ash geopolymer was studied to overcome the rapid set of the geopolymer in this paper. High-calcium fly ash and alkaline solution were used as starting materials to synthesize the geopolymer. Calcium chloride, calcium sulfate, sodium sulfate, and sucrose at dosages of 1wt% and 2wt% of fly ash were selected as admixtures based on concrete knowledge to improve the properties of the geopolymer. The setting time, compressive strength, and degree of reaction were recorded, and the microstructure was examined. The results show that calcium chloride significantly shortens both the initial and final setting times of the geopolymer paste. In addition, sucrose also delays the final setting time significantly. The degrees of reaction of fly ash in the geopolymer paste with the admixtures are all higher than those of the control paste. This contributes to the obvious increases in compressive strength.
NASA Technical Reports Server (NTRS)
Lahoti, G. D.; Akgerman, N.; Altan, T.
1978-01-01
Mild steel (AISI 1018) was selected as model cold-rolling material and Ti-6Al-4V and INCONEL 718 were selected as typical hot-rolling and cold-rolling alloys, respectively. The flow stress and workability of these alloys were characterized and friction factor at the roll/workpiece interface was determined at their respective working conditions by conducting ring tests. Computer-aided mathematical models for predicting metal flow and stresses, and for simulating the shape-rolling process were developed. These models utilize the upper-bound and the slab methods of analysis, and are capable of predicting the lateral spread, roll-separating force, roll torque and local stresses, strains and strain rates. This computer-aided design (CAD) system is also capable of simulating the actual rolling process and thereby designing roll-pass schedule in rolling of an airfoil or similar shape. The predictions from the CAD system were verified with respect to cold rolling of mild steel plates. The system is being applied to cold and hot isothermal rolling of an airfoil shape, and will be verified with respect to laboratory experiments under controlled conditions.
Wang, Chao-Qiang; Lin, Xiao-Yan; He, Ming; Wang, Dan; Zhang, Si-Lan
2017-09-15
The overall objective of this research project is to investigate the feasibility of incorporating oil-based drilling cuttings pyrolysis residues (ODPR) and fly ash serve as replacements for fine aggregates and cementitious materials in concrete. Mechanical and physical properties, detailed environmental performances, and microstructure analysis were carried out. Meanwhile, the early hydration process and hydrated products of ODPR concrete were analyzed with X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results indicated that ODPR could not be categorize into hazardous wastes. ODPR had specific pozzolanic characteristic and the use of ODPR had certain influence on slump and compressive strength of concrete. The best workability and optimal compressive strength were achieved with the help of 35% ODPR. Environmental performance tests came to conclusion that ODPR as recycled aggregates and admixture for the preparation of concrete, from the technique perspective, were the substance of mere environmental contamination. Copyright © 2017 Elsevier B.V. All rights reserved.
An experimental investigation on mechanical behaviour of eco - friendly concrete
NASA Astrophysics Data System (ADS)
Narender Reddy, A.; Meena, T.
2017-11-01
Fly ash (FA) and Alccofine are the eco-friendly materials that can be used in the production of concrete composites. Initially, concrete mixes of M30 grade with replacement of cement by 0%, 5%, 10%, 15%, 20% and 25% by weight of Fly ash were prepared. They were subjected to compression test so as to select the optimum replacement percentage of FA. Keeping this optimum percentage of FA as constant, additional replacement of cement with Alccofine was done varying its replacement in the range of 8%, 10%, 12% and 14%. The mechanical properties such as compressive, split tensile and flexural strengths of these mixes were computed for 7, 14 and 28 days. The results of Eco-Friendly Concrete (EFC) are compared with those of control concrete. It was observed that EFC mixes exhibited superior qualities like quick setting and enhanced workability, their mechanical properties were found to be higher than that of the conventional concrete. This goes to prove that the combination of FA and Alccofine together as replacement for cement would enhance the properties of EFC.
NASA Astrophysics Data System (ADS)
Rum, R. H. M.; Jaini, Z. M.; Boon, K. H.; Khairaddin, S. A. A.; Rahman, N. A.
2017-11-01
This study presents the utilization of rice husk ash (RHA) as sand replacement in foamed concrete. The study focuses on the effect of RHA on the compressive strength of foamed concrete. RHA contains high pozzolanic material that reacts with cementitious to enhance the strength and durability of foamed concrete. RHA also acts as filler causing the foamed concrete to become denser while retaining its unique low density. A total 243 cube specimens was prepared for the compression test. Two sets of mix design were employed at water-cement (W/C) ratio of 0.55, 0.60 and cement-sand ratio of 0.50, 0.33. The results revealed that the presence of RHA as sand replacement resulted in an increase in the compressive strength of foamed concrete. Moreover, 30% to 40% RHA was the optimum content level, contributing to the compressive strength of 18.1 MPa to 22.4 MPa. The W/C ratio and superplasticiser dosage play small roles in improving workability. In contrast, density governs the compressive strength of foamed concrete.
A Dimensional Bus model for integrating clinical and research data
Hum, Richard C; Murphy, James R
2011-01-01
Objectives Many clinical research data integration platforms rely on the Entity–Attribute–Value model because of its flexibility, even though it presents problems in query formulation and execution time. The authors sought more balance in these traits. Materials and Methods Borrowing concepts from Entity–Attribute–Value and from enterprise data warehousing, the authors designed an alternative called the Dimensional Bus model and used it to integrate electronic medical record, sponsored study, and biorepository data. Each type of observational collection has its own table, and the structure of these tables varies to suit the source data. The observational tables are linked to the Bus, which holds provenance information and links to various classificatory dimensions that amplify the meaning of the data or facilitate its query and exposure management. Results The authors implemented a Bus-based clinical research data repository with a query system that flexibly manages data access and confidentiality, facilitates catalog search, and readily formulates and compiles complex queries. Conclusion The design provides a workable way to manage and query mixed schemas in a data warehouse. PMID:21856687
Code of Federal Regulations, 2010 CFR
2010-01-01
... and instrumentation surfaces (that come in contact with the gas) must be made of materials that remain... into contact with the process gas are wholly made of, or lined with, UF6-resistant materials. For the... REGULATORY COMMISSION (CONTINUED) EXPORT AND IMPORT OF NUCLEAR EQUIPMENT AND MATERIAL Pt. 110, App. C...
High Modulus Asphalt Concrete with Dolomite Aggregates
NASA Astrophysics Data System (ADS)
Haritonovs, V.; Tihonovs, J.; Smirnovs, J.
2015-11-01
Dolomite is one of the most widely available sedimentary rocks in the territory of Latvia. Dolomite quarries contain about 1,000 million tons of this material. However, according to Latvian Road Specifications, this dolomite cannot be used for average and high intensity roads because of its low quality, mainly, its LA index (The Los Angeles abrasion test). Therefore, mostly the imported magmatic rocks (granite, diabase, gabbro, basalt) or imported dolomite are used, which makes asphalt expensive. However, practical experience shows that even with these high quality materials roads exhibit rutting, fatigue, and thermal cracks. The aim of the research is to develop a high performance asphalt concrete for base and binder courses using only locally available aggregates. In order to achieve resistance against deformations at a high ambient temperature, a hard grade binder was used. Workability, fatigue and thermal cracking resistance, as well as sufficient water resistance is achieved by low porosity (3-5%) and higher binder content compared to traditional asphalt mixtures. The design of the asphalt includes a combination of empirical and performance based tests, which in laboratory circumstances allow simulating traffic and environmental loads. High performance AC 16 base asphalt concrete was created using local dolomite aggregate with polymer modified (PMB 10/40-65) and hard grade (B20/30) bitumen. The mixtures were specified based on fundamental properties in accordance with EN 13108-1 standard.
Sigaev, Vladimir N; Golubev, Nikita V; Ignat'eva, Elena S; Paleari, Alberto; Lorenzi, Roberto
2014-01-01
Wide-bandgap nanocrystals are an inexhaustible source of tuneable functions potentially addressing most of the demand for new light emitting systems. However, the implementation of nanocrystal properties in real devices is not straightforward if a robust and stable optical component is required as a final result. The achievement of efficient light emission from dense dispersions of Ga-oxide nanocrystals in UV-grade glass can be a breakthrough in this regard. Such a result would permit the fabrication of low cost UV-to-visible converters for monitoring UV-emitting events on a large-scale - from invisible hydrogen flames to corona dispersions. From this perspective, γ-Ga₂O₃ nanocrystals are developed by phase separation in Ga-alkali-germanosilicate glasses, obtaining optical materials based on a UV transparent matrix. Band-to-band UV-excitation of light emission from donor-acceptor pair (DAP) recombination is investigated for the first time in embedded γ-Ga₂O₃. The analysis of the decay kinetics gives unprecedented evidence that nanosized confinement of DAP recombination can force a nanophase to the efficient response of exactly balanced DAPs. The results, including a proof of concept of UV-to-visible viewer, definitely demonstrate the feasibility of workable glass-based fully inorganic nanostructured materials with emission properties borrowed from Ga₂O₃ single-crystals and tailored by the nanocrystal size.
NASA Technical Reports Server (NTRS)
Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.; Underwood, M. L.; Suitor, J.; O'Connor, D.
1993-01-01
Alkali metal thermal to electric converter (AMTEC) designs for space power are numerous, but selection of materials for construction of long-lived AMTEC devices has been limited to electrodes, current collectors, and the solid electrolyte. AMTEC devices with lifetimes greater than 5 years require careful selection and life testing of all hot-side components. The likely selection of a remote condensed design for initial flight test and probable use with a GPHS in AMTEC powered outer planet probes requires the device to be constructed to tolerate T greater than 1150K, as well as exposure to Na(sub (g)), and Na(sub (liq)) on the high pressure side. The temperatures involved make critical high strength and chemical resistance to Na containing Na(sub 2)O. Selection among materials which can be worked should not be driven by ease of fabricability, as high temperature stability is the critical issue. These concepts drive the selection of Mo alloys for Na(sub (liq)) containment in AMTEC cells for T to 1150K operation, as they are significantly stronger than comparable NB or Ta alloys, are less soluble in Na(sub (liq)) containing dissolved Na(sub 2)O, are workable compared to W alloys (which might be used for certain components), and are ductile at the T greater than 500K of proposed AMTEC modules in space applications.
Computer Simulation and ESL Reading.
ERIC Educational Resources Information Center
Wu, Mary A.
It is noted that although two approaches to second language instruction--the communicative approach emphasizing genuine language use and computer assisted instruction--have come together in the form of some lower level reading instruction materials for English as a second language (ESL), advanced level ESL reading materials using computer…
NASA Astrophysics Data System (ADS)
Karolina, R.; Muhammad, W.; Saragih, M. D. S. M.; Mustaqa, T.
2018-02-01
Self Compacting Concrete is a concrete variant that has a high degree of workability and also has great initial strength, but low water cement factor. It is also self-flowable that can be molded on formwork with a very little or no compacted use of compactors. This concrete, using a variety of aggregate sizes, aggregate portions and superplasticizer admixture to achieve a special viscosity that allows it to flow on its own without the aid of a compactor. Lightweight concrete brick is a type of brick made from cement, sand, water, and developers. Lightweight concrete bricks are divided into 2 based on the developed materials used are AAC (Autoclave Aerated Concrete) using aluminum paste and CLC (Cellular Lightweight Concrete) that use Foaming Agent from BASF as a developer material. In this experiment, the lightweight bricks that will be made are CLC type which uses Foaming Agent as the developer material by mixing the Ash Stone produced by Stone Crusher machine which has the density of 2666 kg / m3 as Partial Pair Substitution. In this study the variation of Ash Stone used is 10%, 15%, and 20% of the planned amount of sand. After doing the tasting the result is obtained for 10% variation. Compressive Strength and Absorption Increase will decrease by 25.07% and 39.005% and Variation of 15% compressive strength will decrease by 65,8% and decrease of absorbtion equal to 17,441% and variation of 20% compressive strength will decreased by 67,4 and absorption increase equal to 17,956%.
Ashwell, Douglas James
2016-04-01
The news media play an important role in informing the public about scientific and technological developments. Some argue that restructuring and downsizing result in journalists coming under increased pressure to produce copy, leading them to use more public relations material to meet their deadlines. This article explores science journalism in the highly commercialised media market of New Zealand. Using semi-structured interviews with scientists, science communication advisors and journalists, the study finds communication advisors and scientists believe most media outlets, excluding public service media, report science poorly. Furthermore, restructuring and staff cuts have placed the journalists interviewed under increasing pressure. While smaller newspapers appear to be printing press releases verbatim, metropolitan newspaper journalists still exercise control over their use of such material. The results suggest these journalists will continue to resist increasing their use of public relations material for some time to come. © The Author(s) 2014.
Schlossberg, D
1996-03-01
The combination of fever and rash comprises an extensive differential diagnosis. Many of the causes of this presentation are life-threatening. In this article, rashes are categorized as petechial, maculopapular, vesicular, erythematous, and urticarial. Each type of rash is then divided into infectious etiologies, both treatable and nontreatable, and noninfectious etiologies. It is usually possible to arrive at a workable differential diagnosis when clinical, historical, and epidemiologic factors are considered.
Digital Adultery, "Meta-Anon Widows," Real-World Divorce, and the Need for a Virtual Sexual Ethic
NASA Astrophysics Data System (ADS)
Spencer, William David
Ethical issues that have emerged around relationships in virtual worlds can inform the way we approach the ethics of human/robot relationships. A workable ethic would be one that treats marriage as an enduring human institution and, while we value robots as worthy works of our hands, they are inappropriate partners for marital or sexual relationships.
Quality mind-set overcomes barriers to success.
Anderson, C A; Daigh, R D
1991-02-01
To remove hindrances to fiscal strength, a healthcare facility needs a long-term, organization-wide strategy. Total quality management (TQM) can offer such a solution, but it requires a revised management philosophy. Under TQM, a hospital must adopt a workable definition of quality; develop a customer orientation; form organizational teams to study and revise work processes; involve all employees in quality efforts; and strive for continuous improvements.
1987-03-23
solution . Using the battalion training NCO, senior guidance counselor, operations NCO, SGM, XO and operations officer as trainers will assist both the... towsrd justification of additional advertising funds, if needed. SProviding a workable Total Army Involvement in Recruiting (TAIR) plan on a quarterly... solution to this problem. 0 Have your CLT visit local reserve canters for assistance in gaining access to schools. Many times, members of the reserve units
The need for expanded exploration of matter-antimatter annihilation for propulsion application
NASA Technical Reports Server (NTRS)
Massier, P. F.
1982-01-01
The use of matter-antimatter annihilation as a propulsion application for interstellar travel is discussed. The physical basis for the superior energy release in such a system is summarized, and the problems associated with antimatter production, collection and storage are assessed. Advances in devising a workable propulsion system are reported, and the parameters of an antimatter propulsion system are described.
DoD Implementation of the Better Buying Power Initiatives
2012-12-01
statutory measures (Budget Control Act of 2011), Congress has been directed to face this problem and provide a workable solution or face the evils...Defense Support Program (DSP) to provide the capabilities that the SBIRS has had problems delivering (Richelson, 2007; Werner, 2011). The purpose of the...Defense David Packard took office. They were keen on addressing the problems plaguing defense acquisition: excessive centralization, inefficiencies
Multi-stained whole slide image alignment in digital pathology
NASA Astrophysics Data System (ADS)
Déniz, Oscar; Toomey, David; Conway, Catherine; Bueno, Gloria
2015-03-01
In Digital Pathology, one of the most simple and yet most useful feature is the ability to view serial sections of tissue simultaneously on a computer monitor. This enables the pathologist to evaluate the histology and expression of multiple markers for a patient in a single review. However, the rate limiting step in this process is the time taken for the pathologist to open each individual image, align the sections within the viewer, with a maximum of four slides at a time, and then manually move around the section. In addition, due to tissue processing and pre-analytical steps, sections with different stains have non-linear variations between the two acquisitions, that is, they will stretch and change shape from section to section. To date, no solution has come close to a workable solution to automatically align the serial sections into one composite image. This research work address this problem to obtain an automated serial section alignment tool enabling the pathologists to simply scroll through the various sections in a single viewer. To this aim a multi-resolution intensity-based registration method using mutual information as a similarity metric, an optimizer based on an evolutionary process and a bilinear transformation has been used. To characterize the performance of the algorithm 40 cases x 5 different serial sections stained with hematoxiline-eosine (HE), estrogen receptor (ER), progesterone receptor (PR), Ki67 and human epidermal growth factor receptor 2 (Her2), have been considered. The qualitative results obtained are promising, with average computation time of 26.4s for up to 14660x5799 images running interpreted code.
Rigidified pneumatic composites
NASA Astrophysics Data System (ADS)
van Dessel, Steven
2000-10-01
The overall objective of the research presented in this dissertation was to address global issues of adequate housing for all and the need for more sustainable human settlement. In order to address these, the emerging technology of rigidified pneumatic composites was investigated. Rigidified pneumatic composites (RPC) are defined as thin flexible membrane structures that are pneumatically deployed. After deployment, these structures harden due to chemical or physical change of the membrane. Because of this change, these structures do no longer require pneumatic pressure to maintain their shape. For the first time, a systematic listing of the various means available to develop polymeric materials useful in RPC technology is presented. With the aim to reduce the cost of RPC structures, a new material was proposed, developed, and evaluated. This material involved the formation of a semi-interpenetrating polymer network based on poly vinyl chloride and an acrylate based reactive plasticizer. The economical and environmental performances of RPC structures using this new material were assessed by means of a case study. In this study, the performance of RPC technology was compared with that of a typical wood light frame structure in the application of a small single-family house. The study indicated that the cost of ownership in present day value for the RPC structure was approximately 33% less than the cost of a comparable wood light frame structure. The study also indicated that significant environmental benefits exist with the use of RPC structures. It was found that the RPC structure used significantly less resources compared to the wood light frame structure. About 3.5 times less materials coming from non-renewable fossil resources, about 2.5 times less materials coming from trees, and about 19 times less materials coming from inorganic resources was used in the RPC structure relative to the wood light frame structure. The study concluded with pointing out various means available to further increase the economical and environmental performance of RPC technology. Directions were provided to guide future developments of RPC technology.
9 CFR 3.75 - Housing facilities, general.
Code of Federal Regulations, 2012 CFR
2012-01-01
... nonhuman primates come in contact must be spot-cleaned daily and sanitized in accordance with § 3.84 of... bedding, sand, gravel, grass, or other similar material, and planted enclosures must be raked or spot.... Contaminated material must be removed or replaced whenever raking and spot cleaning does not eliminate odors...
Reuse of “Waste” in Making Building Products –Methodology and Evaluation
The use of industrial by-products as a replacement to mined or extracted materials can save energy and other natural resources. However, it is important that you consider changes in the environmental conditions that a material may come into contact with either through chemical ...
Dynamic Camouflage Materials Based on Silk-Reflectin Chimeras
2012-08-01
Dynamic Camouflage Materials Based on Silk -Reflectin Chimeras Final Performance Report for FA9550-09-1-0513 (Program Manager: Hugh DeLong...efforts to bioengineer silk -reflectin chimeric proteins, with the silk component serving as one of the organizing elements for material functions and...Further contributions may also come from the silk due to its novel light guiding properties and diffractive optics. Variants in silk block sizes
Literature Review of Spin On Glass
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, Reuben James
2016-03-02
Spin on glass (SOG) is a promising material that combines the planarization properties of a low-viscosity liquid with a dielectric constant lower than that of silicon dioxide. However, as this paper will show, this material comes with significant processing and material properties challenges that must be understood and overcome. Significant research has been accomplished through a variety of processing techniques that will be reviewed here.
Biocompatibility of root-end filling materials: recent update
Gupta, Saurabh Kumar; Newaskar, Vilas
2013-01-01
The purpose of a root-end filling is to establish a seal between the root canal space and the periradicular tissues. As root-end filling materials come into contact with periradicular tissues, knowledge of the tissue response is crucial. Almost every available dental restorative material has been suggested as the root-end material of choice at a certain point in the past. This literature review on root-end filling materials will evaluate and comparatively analyse the biocompatibility and tissue response to these products, with primary focus on newly introduced materials. PMID:24010077
49 CFR 173.124 - Class 4, Divisions 4.1, 4.2 and 4.3-Definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... exothermic decomposition even without participation of oxygen (air). A material is excluded from this... external ignition source, can ignite within five (5) minutes after coming in contact with air when tested... material that through a process where the gradual reaction of that substance with oxygen (in air) generates...
Changes Coming to the International System of Units
ERIC Educational Resources Information Center
Aubrecht, Gordon J., II
2012-01-01
The International System of Units (SI) is a coherent system based originally on measurements of properties of material objects. In more recent times, the adopted definitions depend on setting values of universal constants wherever possible. The last remaining human-made material object on which a standard is based is a platinum-iridium kilogram…
Theatrical Makeup Enhances the Drama.
ERIC Educational Resources Information Center
Aiex, Patrick K.
With a little practice, even an amateur or classroom technician can learn the fundamentals of simple theatrical makeup. The principles of stage makeup and its application begin with a knowledge of the materials and the tools used to apply them. Base, liner, rouge, eye shadow, lipstick, and finishing powder are the basic materials. Base comes in…
ERIC Educational Resources Information Center
Science Teacher, 2005
2005-01-01
Scientists using NASA's Swift satellite say they have found newborn black holes, just seconds old, in a confused state of existence. The holes are consuming material falling into them while somehow propelling other material away at great speeds. "First comes a blast of gamma rays followed by intense pulses of x-rays. The energies involved are much…
ERIC Educational Resources Information Center
Fair, Bryan K.
This book is a defense of remedial affirmative action and an assertion that it is a policy that is a fair and workable solution to the chronic problem of racial caste in the United States. The personal narrative of the author, eighth of 10 children born to a single mother on public assistance, is combined with the discussion of American history…
ERIC Educational Resources Information Center
Trump, J. Lloyd
The design described in this book incorporates experiences of the past eight years in a Model Schools Project that involved at various times 34 junior and senior high schools. It also translates many of the major statements issued by the NASSP as guidelines for improving schools into a workable model. The chapters show how the school develops the…
NASA Astrophysics Data System (ADS)
Kameda, Takao; Sugino, Naoto; Takei, Satoshi
2016-10-01
Shear viscosity measurement device was produced to evaluate the injection molding workability for high-performance resins. Observation was possible in shear rate from 10 to 10000 [1/sec] that were higher than rotary rheometer by measuring with a plasticization cylinder of the injection molding machine. The result of measurements extrapolated result of a measurement of the rotary rheometer.
Dark-bright soliton pairs in nonlocal nonlinear media.
Lin, Yuan Yao; Lee, Ray-Kuang
2007-07-09
We study the formation of dark-bright vector soliton pairs in nonlocal Kerr-type nonlinear medium. We show, by analytical analysis and direct numerical calculation, that in addition to stabilize of vector soliton pairs nonlocal nonlinearity also helps to reduce the threshold power for forming a guided bright soliton. With help of the nonlocality, it is expected that the observation of dark-bright vector soliton pairs in experiments becomes more workable.
Silk Purse from a Sow's Ear? Why Knowledge Matters and Why the Draft History NC Will Not Improve It
ERIC Educational Resources Information Center
Hall, Katie; Counsell, Christine
2013-01-01
Katie Hall and Christine Counsell attempt to construct a Key Stage 3 scheme of work out of the draft National Curriculum for history that was released for consultation in England in February 2013. They explain the process by which they attempted to convert the programme of study into a coherent, workable plan that would fulfil the stated aims.…
3rd Miami international conference on alternative energy sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nejat Veziroglu, T.
1980-01-01
The conference includes sessions on solar energy, ocean thermal energy, wind energy, hydro power, nuclear breeders and nuclear fusion, synthetic fuels from coal or wastes, hydrogen production and uses, formulation of workable policies on energy use and energy conservation, heat and energy storage, and energy education. The volume of the proceedings presents the papers and lectures in condensed format grouped by subject under forty-two sessions for 319 presentations.
Switching-angle sample spinning NMR probe with a commercially available 20 kHz spinning system
NASA Astrophysics Data System (ADS)
Mizuno, Takashi; Takegoshi, K.; Terao, Takehiko
2004-11-01
A switching-angle sample spinning (SASS) probe workable at high spinning speeds was developed using a commercially available rotor/housing system. Details of the construction are described. As application examples of the SASS probe, we report experiments of powder pattern separation at the spinning speed of 20 kHz and broadband 13C- 13C polarization transfer at 16 kHz.
ERIC Educational Resources Information Center
Classen, Albrecht
2018-01-01
Recent debates about the future of academia have focused primarily on teaching the STEM subjects. This is certainly a valuable call for action, but it also threatens to ignore the significant contributions of the humanities and other fields. This article presents a workable alternative by way of looking at more technical writings by 18th-century…
Remotely Operated Vehicle ROV/AUV Reliability Study. Phase 2.
1989-09-01
produce workable configurations for large diameter cyl nders strong enough to survive high compression forces. 11 1.4.5.1.1 Composites Although FWE...Since the main cylinder in manned submersibles is typically large diameter , and the interior is only partially filled with equipment, these systems...ceramics involve control of tolerances when manufacturing large diameter cylinders, although ongoing R&D may provide solutions to this. The major
Applying lessons learned in communities to programs and policies at the federal level.
Chang, Debbie I
2006-01-01
As solutions to the problems of the uninsured are debated, there are lessons to be learned from community-based initiatives. Such efforts can provide information on different models as well as key political lessons. Defining the specific role that community efforts play is also critical. Actively involving community stakeholders of such community initiatives in health care policy debates will result in more workable policies.
ERIC Educational Resources Information Center
Sharma, Mahesh C., Ed.; Travaglini, Lillian E., Ed.
1988-01-01
Math Notebook is a publication issued 10 times a year, with each issue focusing on a particular learning problem in mathematics and its diagnosis and remediation through practical, workable strategies for use by teaches, parents, and tutors. All the articles were written by Mahesh C. Sharma, with the exception of "The Japanese Soroban," by Frances…
Reliable Video Analysis Helps Security Company Grow
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meurer, Dave; Furgal, Dave; Hobson, Rick
Armed Response Team (ART) has grown to become the largest locally owned security company in New Mexico. With technical assistance from Sandia National Laboratories through the New Mexico Small Business Assistance (NMSBA) Program, ART got help so they could quickly bring workable video security solutions to market. By offering a reliable video analytic camera system, they’ve been able to reduce theft, add hundreds of clients, and increase their number of employees.
Waste tyre rubberized concrete: properties at fresh and hardened state.
Aiello, M A; Leuzzi, F
2010-01-01
The main objective of this paper is to investigate the properties of various concrete mixtures at fresh and hardened state, obtained by a partial substitution of coarse and fine aggregate with different volume percentages of waste tyres rubber particles, having the same dimensions of the replaced aggregate. Workability, unit weight, compressive and flexural strength and post-cracking behaviour were evaluated and a comparison of the results for the different rubcrete mixtures were proposed in order to define the better mix proportions in terms of mechanical properties of the rubberized concrete. Results showed in this paper were also compared to data reported in literature. Moreover, a preliminary geometrical, physical and mechanical characterization on scrap tyre rubber shreds was made. The rubberized concrete mixtures showed lower unit weight compared to plain concrete and good workability. The results of compressive and flexural tests indicated a larger reduction of mechanical properties of rubcrete when replacing coarse aggregate rather than fine aggregate. On the other hand, the post-cracking behaviour of rubberized concrete was positively affected by the substitution of coarse aggregate with rubber shreds, showing a good energy absorption and ductility indexes in the range observed for fibrous concrete, as suggested by standard (ASTM C1018-97, 1997). 2010 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Memon, Fareed Ahmed; Nuruddin, Muhd Fadhil; Shafiq, Nasir
2013-02-01
The effect of silica fume on the fresh and hardened properties of fly ash-based self-compacting geopolymer concrete (SCGC) was investigated in this paper. The work focused on the concrete mixes with a fixed water-to-geopolymer solid (W/Gs) ratio of 0.33 by mass and a constant total binder content of 400 kg/m3. The mass fractions of silica fume that replaced fly ash in this research were 0wt%, 5wt%, 10wt%, and 15wt%. The workability-related fresh properties of SCGC were assessed through slump flow, V-funnel, and L-box test methods. Hardened concrete tests were limited to compressive, splitting tensile and flexural strengths, all of which were measured at the age of 1, 7, and 28 d after 48-h oven curing. The results indicate that the addition of silica fume as a partial replacement of fly ash results in the loss of workability; nevertheless, the mechanical properties of hardened SCGC are significantly improved by incorporating silica fume, especially up to 10wt%. Applying this percentage of silica fume results in 4.3% reduction in the slump flow; however, it increases the compressive strength by 6.9%, tensile strength by 12.8% and flexural strength by 11.5%.
Antibiotics Smart Use: a workable model for promoting the rational use of medicines in Thailand
Chongtrakul, Pisonthi; Anuwong, Kunyada; Pumtong, Somying; Kongsomboon, Kedsenee; Butdeemee, Parichart; Khonglormyati, Jurairat; Chomyong, Santi; Tongyoung, Parnuchote; Losiriwat, Suraphol; Seesuk, Piyanooch; Suwanwaree, Pongthep; Tangcharoensathien, Viroj
2012-01-01
Abstract The Antibiotics Smart Use (ASU) programme was introduced in Thailand as a model to promote the rational use of medicines, starting with antibiotics. The programme’s first phase consisted of assessing interventions intended to change prescribing practices; the second phase examined the feasibility of programme scale-up. Currently the programme is in its third phase, which centres on sustainability. This paper describes the concept behind ASU, the programme’s functional modalities, the development of its conceptual framework and the implementation of its first and second phases. To change antibiotic prescription practices, multifaceted interventions at the individual and organizational levels were implemented; to maintain behaviour change and scale up the programme, interventions at the network and policy levels were used. The National Health Security Office has adopted ASU as a pay-for-performance criterion, a major achievement that has led to the programme’s expansion nationwide. Despite limited resources, programme scale-up and sustainability have been facilitated by the promotion of local ownership and mutual recognition, which have generated pride and commitment. ASU is clearly a workable entry point for efforts to rationalize the use of medicines in Thailand. Its long-term sustainability will require continued local commitment and political support, effective auditing and integration of ASU into routine systems with appropriate financial incentives. PMID:23284196
Antibiotics Smart Use: a workable model for promoting the rational use of medicines in Thailand.
Sumpradit, Nithima; Chongtrakul, Pisonthi; Anuwong, Kunyada; Pumtong, Somying; Kongsomboon, Kedsenee; Butdeemee, Parichart; Khonglormyati, Jurairat; Chomyong, Santi; Tongyoung, Parnuchote; Losiriwat, Suraphol; Seesuk, Piyanooch; Suwanwaree, Pongthep; Tangcharoensathien, Viroj
2012-12-01
The Antibiotics Smart Use (ASU) programme was introduced in Thailand as a model to promote the rational use of medicines, starting with antibiotics. The programme's first phase consisted of assessing interventions intended to change prescribing practices; the second phase examined the feasibility of programme scale-up. Currently the programme is in its third phase, which centres on sustainability. This paper describes the concept behind ASU, the programme's functional modalities, the development of its conceptual framework and the implementation of its first and second phases. To change antibiotic prescription practices, multifaceted interventions at the individual and organizational levels were implemented; to maintain behaviour change and scale up the programme, interventions at the network and policy levels were used. The National Health Security Office has adopted ASU as a pay-for-performance criterion, a major achievement that has led to the programme's expansion nationwide. Despite limited resources, programme scale-up and sustainability have been facilitated by the promotion of local ownership and mutual recognition, which have generated pride and commitment. ASU is clearly a workable entry point for efforts to rationalize the use of medicines in Thailand. Its long-term sustainability will require continued local commitment and political support, effective auditing and integration of ASU into routine systems with appropriate financial incentives.
Test of cold asphalt storability based on alternative approaches
NASA Astrophysics Data System (ADS)
Abaffyová, Zora; Komačka, Jozef
2017-09-01
Cold asphalt products for potholes repairs should be workable (soft enough) for long time to ensure their applicability. Storability is assessed indirectly using various tests of workability. Therefore, simple test methods (self-compaction and disintegration test) was developed and verified to investigate changes of storability of this group of cold asphalts. Selfcompaction of the tested mixture in the upturned Abram’s cone for the cement concrete slump test and in the mould for the California Bearing Ratio test was assessed in first stage. After that the video record of disintegration test was taken. During this test, the mould was lifted up and the mixture fell off the mould (Abram’s cone) or disintegrate (CBR mould). The drop of surface after 10 min self-compaction and netto time related to falling out or disintegration of the mixture were used to evaluate the mixture from storability point of view. It was found out the self-compaction test has not a potential to reveal and prove changes of mixture properties. Based on the disintegration test results it can be stated this test at 5 °C using the upturned Abram’s cone could be a suitable approach to determine qualitative changes of a cold mixture from storability point of view.
Tribe, David
2014-07-03
Australia is a federation of States. This political structure necessitates collaborative arrangements between Australian governments to harmonize national regulation of gene technology and food standards. Extensive political negotiation among institutions of federal government has managed regulation of GM crops and food. Well-developed human resources in Australian government provided numerous policy documents facilitating a transparent political process. Workable legislation has been devised in the face of criticisms of gene technology though the political process. Conflicts between potential disruptions to food commodity trade by precautionary proposals for environmental protection were one cause of political tensions, and differences in policy priorities at regional political levels versus national and international forums for negotiation were another. Australian policy outcomes on GM crops reflect (a) strong economic self-interest in innovative and productive farming, (b) reliance on global agricultural market reforms through the Cairns trade group and the WTO, and (c) the importance of Codex Alimentarius and WTO instruments SPS and TBT. Precautionary frameworks for GM food safety assurance that are inconsistent with WTO obligations were avoided in legislation. Since 2008 the 2 major parties, Australian Labor Party (ALP) and the Liberals appear to have reached a workable consensus at the Federal policy level about an important role for agricultural biotechnology in Australia's economic future.
Tribe, David
2014-01-01
Australia is a federation of States. This political structure necessitates collaborative arrangements between Australian governments to harmonize national regulation of gene technology and food standards. Extensive political negotiation among institutions of federal government has managed regulation of GM crops and food. Well-developed human resources in Australian government provided numerous policy documents facilitating a transparent political process. Workable legislation has been devised in the face of criticisms of gene technology though the political process. Conflicts between potential disruptions to food commodity trade by precautionary proposals for environmental protection were one cause of political tensions, and differences in policy priorities at regional political levels versus national and international forums for negotiation were another. Australian policy outcomes on GM crops reflect (a) strong economic self-interest in innovative and productive farming, (b) reliance on global agricultural market reforms through the Cairns trade group and the WTO, and (c) the importance of Codex Alimentarius and WTO instruments SPS and TBT. Precautionary frameworks for GM food safety assurance that are inconsistent with WTO obligations were avoided in legislation. Since 2008 the 2 major parties, Australian Labor Party (ALP) and the Liberals appear to have reached a workable consensus at the Federal policy level about an important role for agricultural biotechnology in Australia's economic future. PMID:25437242
Properties of concrete containing foamed concrete block waste as fine aggregate replacement
NASA Astrophysics Data System (ADS)
Muthusamy, K.; Budiea, A. M. A.; Zaidan, A. L. F.; Rasid, M. H.; Hazimmah, D. S.
2017-11-01
Environmental degradation due to excessive sand mining dumping at certain places and disposal of foamed concrete block waste from lightweight concrete producing industry are issues that should be resolved for a better and cleaner environment of the community. Thus, the main intention of this study is to investigate the potential of foamed concrete block waste as partial sand replacement in concrete production. The foamed concrete waste (FCW) used in this research that were supplied by a local lightweight concrete producing industry. The workability and compressive strength of concrete containing various percentage of foamed concrete waste as partial sand replacement has been investigated. Prior to the use, the foamed concrete waste were crushed to produce finer particles. Six concrete mixes containing various content of crushed foamed concrete waste that are 0%, 10%, 20%, 30%, 40% and 50% were used in this experimental work. Then the prepared specimens were placed in water curing until the testing age. Compressive strength test and flexural strength tests were conducted at 7, 14 and 28 days. The result shows that integration of crushed foamed concrete waste as partial sand replacement in concrete reduces the mix workability. It is interesting to note that both compressive strength and flexural strength of concrete improves when 30% crushed foamed concrete waste is added as partial sand replacement.
Van den Heede, Philip; Ringoot, Niels; Beirnaert, Arno; Van Brecht, Andres; Van den Brande, Erwin; De Schutter, Geert; De Belie, Nele
2015-01-01
Nowadays, more efforts towards sustainability are required from the concrete industry. Replacing traditional aggregates by recycled bottom ash (BA) from municipal solid waste incineration can contribute to this goal. Until now, only partial replacement has been considered to keep the concrete workability, strength and durability under control. In this research, the feasibility of a full aggregate replacement was investigated for producing prefabricated Lego bricks. It was found that the required compressive strength class for this purpose (C20/25) could be achieved. Nevertheless, a thorough understanding of the BA properties is needed to overcome other issues. As BA is highly absorptive, the concrete’s water demand is high. This workability issue can be dealt with by subjecting the fine BA fraction to a crushing operation to eliminate the porous elements and by pre-wetting the fine and coarse BA fractions in a controlled manner. In addition, a reactive NaOH washing is needed to avoid formation of longitudinal voids and the resulting expansion due to the metallic aluminum present in the BA. Regarding the long-term behavior, heavy metal leaching and freeze-thaw exposure are not problematic, though there is susceptibility to acetic and lactic acid attack and maybe increased sensitivity to alkali-silica reaction. PMID:28787809
Van den Heede, Philip; Ringoot, Niels; Beirnaert, Arno; Van Brecht, Andres; Van den Brande, Erwin; De Schutter, Geert; De Belie, Nele
2015-12-25
Nowadays, more efforts towards sustainability are required from the concrete industry. Replacing traditional aggregates by recycled bottom ash (BA) from municipal solid waste incineration can contribute to this goal. Until now, only partial replacement has been considered to keep the concrete workability, strength and durability under control. In this research, the feasibility of a full aggregate replacement was investigated for producing prefabricated Lego bricks. It was found that the required compressive strength class for this purpose (C20/25) could be achieved. Nevertheless, a thorough understanding of the BA properties is needed to overcome other issues. As BA is highly absorptive, the concrete's water demand is high. This workability issue can be dealt with by subjecting the fine BA fraction to a crushing operation to eliminate the porous elements and by pre-wetting the fine and coarse BA fractions in a controlled manner. In addition, a reactive NaOH washing is needed to avoid formation of longitudinal voids and the resulting expansion due to the metallic aluminum present in the BA. Regarding the long-term behavior, heavy metal leaching and freeze-thaw exposure are not problematic, though there is susceptibility to acetic and lactic acid attack and maybe increased sensitivity to alkali-silica reaction.
NASA Astrophysics Data System (ADS)
Hasan, Mohd Rosli Mohd; Hamzah, Meor Othman; Yee, Teh Sek
2017-10-01
Experimental works were conducted to evaluate the properties of asphalt binders and mixtures produced using a relatively new silane additive, named ZycoTherm. In this study, 0.1wt% ZycoTherm was blended with asphalt binder to enable production of asphalt mixture at lower than normal temperatures, as well as improve mix workability and compactability. Asphalt mixture performances towards pavement distresses in tropical climate region were also investigated. The properties of control asphalt binders (60/70 and 80/10 penetration grade) and asphalt binders incorporating 0.1% ZycoTherm were reported based on the penetration, softening point, rotational viscosity, complex modulus and phase angle. Subsequently, to compare the performance of asphalt mixture incorporating ZycoTherm with the control asphalt mixture, cylindrical samples were prepared at recommended temperatures and air voids depending on the binder types and test requirements. The samples were tested for indirect tensile strength (ITS), resilient modulus, dynamic creep, Hamburg wheel tracking and moisture induced damage. From compaction data using the Servopak gyratory compactor, specimen prepared using ZycoTherm exhibit higher workability and compactability compared to the conventional mixture. From the mixture performance test results, mixtures prepared with ZycoTherm showed comparable if not better performance than the control sample in terms of the resistance to moisture damage, permanent deformation and cracking.
EAST FACE OF REACTOR BASE. COMING TOWARD CAMERA IS EXCAVATION ...
EAST FACE OF REACTOR BASE. COMING TOWARD CAMERA IS EXCAVATION FOR MTR CANAL. CAISSONS FLANK EACH SIDE. COUNTERFORT (SUPPORT PERPENDICULAR TO WHAT WILL BE THE LONG WALL OF THE CANAL) RESTS ATOP LEFT CAISSON. IN LOWER PART OF VIEW, DRILLERS PREPARE TRENCHES FOR SUPPORT BEAMS THAT WILL LIE BENEATH CANAL FLOOR. INL NEGATIVE NO. 739. Unknown Photographer, 10/6/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
A primer on wood as dock construction material
Stan Lebow
2007-01-01
To be a successful marina owner and operator, itâs important to understand all the facets of oneâs facility, including the intricacies of one part of the marina that most boaters take for granted: the docks. When it comes to dock construction, marinas have a wide-range of materials to choose from, with one of the most commonly used materials being preservative-treated...
coming to NREL, Dave was an Air Force officer and led a variety of defense science and engineering efforts in fluid dynamics, combustion, structures, materials, nanotechnology, multidisciplinary design
Liu, Ming-Chung; Lee, Cheng-Chung; Kaneko, Masaaki; Nakahira, Kazuhide; Takano, Yuuichi
2006-03-01
MgF2 and GdF3 materials, used for a single-layer coating at 193 nm, are deposited by a resistive-heating boat at specific substrate temperatures. Optical characteristics (transmittance, refractive index, extinction coefficient, and optical loss) and microstructures (morphology and crystalline structure) are investigated and discussed. Furthermore, MgF2 is used as a low-index material, and GdF3 is used as a high-index material for multilayer coatings. Reflectance, stress, and the laser-induced damage threshold (LIDT) are studied. It is shown that MgF2 and GdF3 thin films, deposited on the substrate at a temperature of 300 degrees C, obtain good quality thin films with high transmittance and little optical loss at 193 nm. For multilayer coatings, the stress mainly comes from MgF2, and the absorption comes from GdF3. Among those coatings, the sixteen-layer design, sub/(1.4L 0.6H)8/air, shows the largest LIDT.
Village Science: A Resource Handbook for Rural Alaskan Teachers.
ERIC Educational Resources Information Center
Dick, Alan
A resource handbook for rural Alaskan teachers covers village science, to make basic science concepts relevant to the physical environment in villages. Material is intended for use as filler for weeks that come up short on science materials, to provide stimulation for students who cannot see the relevance of science in their lives, and to help…
Writers Handbook for the Development of Educational Materials. Bulletin, 1959, No. 19
ERIC Educational Resources Information Center
Nolen, Barbara; Goetz, Delia
1959-01-01
This "Writers' Handbook" was prepared in response to the many requests for "a book that tells how to write textbooks and other educational materials for schools." These requests have come from educators of other countries as well as from the United States. The authors believe that the handbook holds valuable information and suggestions for heads…
... your menstrual flow. They come in different sizes, styles, and thicknesses. Some have extra material on the ... Bulletins Patient Education Green Journal Clinical Updates Practice Management Coding Health Info Technology Professional Liability Managing Your ...
Promoting the use of crumb rubber concrete in developing countries.
Batayneh, Malek K; Marie, Iqbal; Asi, Ibrahim
2008-11-01
The use of accumulated waste materials in third world countries is still in its early phases. It will take courage for contractors and others in the construction industry to recycle selected types of waste materials in the concrete mixes. This paper addresses the recycling of rubber tires accumulated every year in Jordan to be used in concrete mixes. The main objectives of this research were to provide more scientific evidence to support the use of legislation or incentive-based schemes to promote the reuse of accumulated waste tires. This research focused on using crumb tires as a replacement for a percentage of the local fine aggregates used in the concrete mixes in Jordan. Different concrete specimens were prepared and tested in terms of uniaxial compression and splitting tension. The main variable in the mixture was the volumetric percentage of crumb tires used in the mix. The test results showed that even though the compressive strength is reduced when using the crumb tires, it can meet the strength requirements of light weight concrete. In addition, test results and observations indicated that the addition of crumb rubber to the mix has a limited effect toward reducing the workability of the mixtures. The mechanical test results demonstrated that the tested specimens of the crumb rubber concrete remained relatively intact after failure compared to the conventional concrete specimens. It is also concluded that modified concrete would contribute to the disposal of the non-decaying scrap tires, since the amount being accumulated in third world countries is creating a challenge for proper disposal. Thus, obliging authorities to invest in facilitating the use of waste tires in concrete, a fundamental material to the booming construction industry in theses countries, serves two purposes.
Micro-processing of NiMnGa shape memory alloy by using a nanosecond fiber laser
NASA Astrophysics Data System (ADS)
Biffi, C. A.; Tuissi, A.
2016-04-01
The interest on Ferromagnetic Shape Memory Alloys (FSMAs), such as NiMnGa, is growing up, thanks to their functional properties to be employed in a new class of micro-devices. The most evident critical issue, limiting the use of these systems in the production of industrial devices, is the brittleness of the bulk material; its workability by using convectional processing methods is very limited. Thus, alternative processing methods, including laser processing, are encouraged for the manufacture of FSMAs based new devices. In this work, the effect of the nanosecond laser microprocessing on Ni45Mn33Ga22 [at%] has been studied. Linear grooves were realized by a nanosecond 30 W fiber laser; the machined surfaces were analyzed with scanning electron microscopy, coupled with energetic dispersion spectroscopy for the composition analysis. The morphology of the grooves was affected by the laser scanning velocity and the number of laser pulses while the measured material removal rate appeared to be influenced mainly by the number of laser pulses. Compositional modification, associated to the loss of Ga content, was detected only for the lower scanning velocity, because of the high fluence. On the contrary, by increasing the velocity up to 1000 mm/s no Ga loss can be seen, making possible the laser processing of this functional alloy without its chemical modification. The use of short pulses allowed also to reduce the amount of recast material and the compositional change with respect to long pulses. Finally, the calorimetric analysis indicated that laser nanosecond microprocessing could affect the functional properties of this alloy: a larger decrease of the characteristic temperatures of the martensitic transformation was observed in correspondence of the low scanning velocity.
ERIC Educational Resources Information Center
Alaska Office of the Governor, Juneau.
In 1987, the Governor of Alaska's Interim Commission on Children and Youth was given two tasks: (1) to develop a plan for a first-class child care system for working parents statewide that is workable, fair and sensibly integrates with the public schools; and (2) to produce a comprehensive plan to combat the problems facing Alaskans so they are…
Clinical leadership: the elephant in the room.
Edmonstone, John
2009-01-01
The article explores the concept of clinical leadership in the National Health Service in the UK by seeking to establish a workable definition and by contrasting it with managerial leadership, focussing on the 'disconnected hierarchy' in professional organizations. It proposes that the problems faced by clinical leadership relate to the current nature of general management in the NHS and concludes by suggesting that clinical leadership is the 'elephant in the room'-often ignored or unaddressed.
Molecular Probes in Marine Ecology: Concepts, Techniques and Applications.
1991-08-16
AD-A240 938 FINAL TECNCAL REPORT Title: Molecular Probes In Marine Ecology: Concepts, Techniques and Applications Office of Naval Research Program ...Contact: Leslie D. Garrick, Office of Sponsored Programs (508) 548-3705, ext. 218 Date: August 16, 1991 91-11818 DISCLAIMER NOTICE THIS DOCUMENT IS BEST...disguise, embi-aces the many questions and seeks workable solutions. The 1990 MBL marine ecology course, entered into its second year of a program in
Environmental Early Warning Systems (EEWS): Equation Writer’s Manual.
1986-07-01
Flowchart 17 2-3 Preliminary Equation Form in Non-EEWS Format 20 2-4 Completed EEWS Form for a Coastal Zone Consideration 21 2-5 Data Ready to Be Loaded 24...Area into workable Subtopics. 4. Formulate flowcharts to separate and show interrelationships between Subtopic Areas and their desired outputs. 5...Army demand criteria (Army background). 9. Refine flowcharts for each specific Subtopic Area and estimate difficulty of accomplishing each step (Figure
ERIC Educational Resources Information Center
Swedish Parliament, Stockholm. Committee on Mass Media.
The Swedish government appointed a parliamentary committee on mass media in 1982 to investigate the mass media structure of the country. The committee was charged with the drafting of workable principles for the further development and utilization of new techniques, e.g., satellites and cable services. This report outlines the main tasks involved…
Reliable Video Analysis Helps Security Company Grow
Meurer, Dave; Furgal, Dave; Hobson, Rick
2018-05-11
Armed Response Team (ART) has grown to become the largest locally owned security company in New Mexico. With technical assistance from Sandia National Laboratories through the New Mexico Small Business Assistance (NMSBA) Program, ART got help so they could quickly bring workable video security solutions to market. By offering a reliable video analytic camera system, theyâve been able to reduce theft, add hundreds of clients, and increase their number of employees.
Army Sustainment. Volume 42, Issue 3. May-June 2010
2010-06-01
created smart cards, refined the content and layout of routine briefs, and developed a workable battle rhythm for the rotation. Many...of classroom MDMP exercise is their only MDMP experience. (Photo by MAJ Christopher LeCron) MAY–jUNE 2010 17 headquarters’ G/S–4 and LNO, ensuring...CTSSB proceed ing. After organizing the survey data, 10 Centra class- rooms were created in ALMS. These classrooms were designated as the sites for each
Hot working behavior of selective laser melted and laser metal deposited Inconel 718
NASA Astrophysics Data System (ADS)
Bambach, Markus; Sizova, Irina
2018-05-01
The production of Nickel-based high-temperature components is of great importance for the transport and energy sector. Forging of high-temperature alloys often requires expensive dies, multiple forming steps and leads to forged parts with tolerances that require machining to create the final shape and a large amount of scrap. Additive manufacturing offers the possibility to print the desired shapes directly as net-shape components, requiring only little additional effort in machining. Especially for high-temperature alloys carrying a large amount of energy per unit mass, additive manufacturing could be more energy-efficient than forging if the energy contained in the machining scrap exceeds the energy needed for powder production and laser processing. However, the microstructure and performance of 3d-printed parts will not reach the level of forged material unless further expensive processes such as hot-isostatic pressing are used. Using the design freedom and possibilities to locally engineer material, additive manufacturing could be combined with forging operations to novel process chains, offering the possibility to reduce the number of forging steps and to create near-net shape forgings with desired local properties. Some innovative process chains combining additive manufacturing and forging have been patented recently, but almost no scientific knowledge on the workability of 3D printed preforms exists. The present study investigates the flow stress and microstructure evolution during hot working of pre-forms produced by laser powder deposition and selective laser melting (Figure 1) and puts forward a model for the flow stress.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Batool, Syeda Adila; Chuadhry, Muhammad Nawaz
2009-01-15
The contribution of existing municipal solid waste management to emission of greenhouse gases and the alternative scenarios to reduce emissions were analyzed for Data Ganj Bukhsh Town (DGBT) in Lahore, Pakistan using the life cycle assessment methodology. DGBT has a population of 1,624,169 people living in 232,024 dwellings. Total waste generated is 500,000 tons per year with an average per capita rate of 0.84 kg per day. Alternative scenarios were developed and evaluated according to the environmental, economic, and social atmosphere of the study area. Solid waste management options considered include the collection and transportation of waste, collection of recyclablesmore » with single and mixed material bank container systems (SMBCS, MMBCS), material recovery facilities (MRF), composting, biogasification and landfilling. A life cycle inventory (LCI) of the six scenarios along with the baseline scenario was completed; this helped to quantify the CO{sub 2} equivalents, emitted and avoided, for energy consumption, production, fuel consumption, and methane (CH{sub 4}) emissions. LCI results showed that the contribution of the baseline scenario to the global warming potential as CO{sub 2} equivalents was a maximum of 838,116 tons. The sixth scenario had a maximum reduction of GHG emissions in terms of CO{sub 2} equivalents of -33,773 tons, but the most workable scenario for the current situation in the study area is scenario 5. It saves 25% in CO{sub 2} equivalents compared to the baseline scenario.« less
Design, properties, and weldability of advanced oxidation-resistant FeCrAl alloys
Gussev, M. N.; Field, K. G.; Yamamoto, Y.
2017-05-05
FeCrAl alloys are promising as corrosion- and oxidation-resistance materials for extreme high-temperature applications. However, further alloy design and improvement requires a delicate balance between workability, weldability, propensity for '-phase formation, among other factors. Here, a series of advanced oxidant resistant FeCrAl alloys were produced and investigated. Variants with Al (+2%), Nb (+1%), and TiC (0.1, 0.3, and 1%) additions over the reference alloy (Fe-13%Cr-5%Al) were characterized in detail before and after controlled laser beam welding using tensile tests with digital image correlation, SEM-EBSD analysis, and fractography. All investigated alloys demonstrated yield stress in the weldment over 500 MPa; no welding-inducedmore » cracking was observed. However, it was shown that the increase in the Al-content over 5% was detrimental leading to a brittle fracture mechanism and decreased ductility in the weldment. At the same time, Nb and TiC additions were beneficial for preventing grain growth and reducing local softening (yield stress reduction) in the heat-affected zone. The 1% TiC addition also effectively refined grain size in the weldment.« less