Physical Properties and Leachability of MLW Stream Containing Cr, Ni and Cd Immobilized in a Cement Matrix

1988 ◽  
Vol 127 ◽  
Author(s):  
E. Zamorani ◽  
I. A. Sheikh ◽  
M. Della Rossa ◽  
G. Serrini

ABSTRACTCement samples containing variable amounts of Cr(III) or Ni(II) or Cd(II) as chloride admixtures present in a MLW stream from reprocessing of spent fuel were prepared under established procedure. Due to the high pH generated in the cement clinker hydration, respective metal hydroxides are formed and improve the physical characteristics of the cement matrix. An increase in the value of the compressive strength was observed when about 7% of the above elements were blended in cement. The increase depends on the nature of the element in the sequence Cr >Ni >Cd.The leach tests confirm the formation of insoluble hydroxide presenting a low concentration in the leachate corresponding to 0.05, 0.004 and 0.052 mg.L−1 for Cr, Ni and Cd, respectively. On the other hand, the hydro-lyzed chloride ions seem to react with calcium with consequent increased degradation of the cement matrix.

Alloy Digest ◽  
1960 ◽  
Vol 9 (7) ◽  

Abstract HAYNES STELLITE 98M2 Alloy is a cobalt-base alloy having higher compressive strength and higher hardness than all the other cobalt-base alloys at room temperature and in the red heat range. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive strength as well as fracture toughness. It also includes information on heat treating, machining, and joining. Filing Code: Co-22. Producer or source: Haynes Stellite Company.


2018 ◽  
Vol 149 ◽  
pp. 01093
Author(s):  
Benyamina Smain ◽  
Siham Kamali-Bernard ◽  
Kenai Said ◽  
Menadi Belkacem

Self-compacting concretes (SCC), are hyper-fluid concretes, placed without vibration and are considered as one of the most important innovations of the last decade in construction. SCCs offer many advantages, due to their exceptional characteristics of flow and filling of formwork. Their compositions require a large quantity of fines in order to limit bleeding and segregation. Hence, the use of crushed sand (SC), rich in limestone fines (CF) in the manufacture of self-placing concretes (SCC), can be considered as an alternative source of fillers. These sands reduce the cost of SCC by reducing the high demand for fillers on the one hand and on the other hand, obtaining SCC with good physical and mechanical properties. The main purpose of this paper is to examine the effect of different percentages (0, 5, 10, 15, and 20%) of (CF) in crushed sand on SCC performance. The evolution of the compressive strength, the porosity accessible to water and the migration coefficient of the chloride ions were evaluated. The Okamura method was used for the formulation of all SCC mixtures. Sand/mortar (S/M), water/cement (W / C) ratios and superplasticizer content were kept constant. The results show that (CF) reduce the compressive strength but contribute to the reduction of porosity and migration of chloride ions.


2011 ◽  
Vol 396-398 ◽  
pp. 380-385
Author(s):  
Lei Wang ◽  
Ye Wang ◽  
Tian Hua Yang ◽  
Run Dong Li

Large amount of emissions from industrial waste residue to the environment has caused serious pollutions. Utilization way to using industrial waste residue preparing sulfoaluminate cement (SAC) is got much attention of scholars both at home and abroad. It summarized the present researches for preparation of SAC from industrial waste residue (IWR). Sintering temperature, mineral composition, physical properties (fineness, standard viscosity, setting time), mechanical properties (compressive strength, flexural strength) and corrosion resistance of cement clinker were analyzed. Preparation of SAC clinker using IWR is a very promising environmental technology.


1992 ◽  
Vol 73 (3) ◽  
pp. 941-945 ◽  
Author(s):  
G. Enhorning ◽  
B. Shumel ◽  
L. Keicher ◽  
J. Sokolowski ◽  
B. A. Holm

The hypophase exchanger is a recently developed device that makes it possible to replace the liquid in the sample chamber of a pulsating bubble surfactometer, after a bubble has been formed, without changing the size of the bubble. A surfactant film outlining the bubble will retain its surface properties, provided the liquid entering the sample chamber and replacing the hypophase is inert. If, on the other hand, the new hypophase consists of a phospholipase solution, the physical properties of the film are seriously affected. It was found that when phospholipase C, even at low concentration, entered the sample chamber, the physical properties were significantly changed. Phospholipase A2 had to be added at a higher concentration to exert a similar effect. It is postulated that the site of action of phospholipase A2 may be partly protected in the hydrophobic region of the tightly packed surfactant film.


1997 ◽  
Vol 37 (5) ◽  
pp. 509 ◽  
Author(s):  
P. J. Holst ◽  
R. S. Hegarty ◽  
N. M. Fogarty ◽  
D. L. Hopkins

Summary. Two hundred and eighty-three lambskins were derived from the progeny of Merino (M), Texel (T), Poll Dorset (PD) and Border Leicester (BL) sires individually mated to Merino and Border Leicester × Merino (BLM) ewes giving 6 genotypes (M × M, T × M, PD × M, BL × M, T × BLM and PD × BLM). The lambs were shorn at 14 weeks and slaughtered (about 20 weeks later) at minimum carcass weights of 18 and 22 kg for ewe and cryptorchid sexes respectively. The ewe lambskins were fellmongered and the pelts processed to nappa, while the cryptorchids were processed to wool-on tannage. Comparative information on fibre metrology, skin mensuration, physical strength of the leather and commercial utility was collected. Skins from all genotypes had a surface area >0.75 m2 and satisfactory physical properties. Pinhole was common amongst all genotypes, whereas ribbyness was largely a Merino trait. Ribbyness was associated with more frequent scarring from shearing damage and processing, indicating that Merino skins are least desirable for production of lamb nappa. The fine diameter and low medullation of Merino wool differed from all the other genotypes whose wool can be classed as industrial. After trimming to a 25 mm nap, lambskins of all genotypes were suitable for wool-on leather products. Skins from well managed lambs of all genotypes would be suitable as wool-on skins.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bharath Seshadri ◽  
Kaushik Selva Dhanush Ravi ◽  
Illias Hischier ◽  
Arno Schlueter

Purpose With a growing list of available materials and processes, the inherent mechanical and thermophysical properties of three-dimensional (3D) prints are important design targets. This paper aims to study the functionality of binder jet 3D printed objects for thermally activated building construction elements and recyclable formwork for concrete structures. Design/methodology/approach Binder jet printed sand samples with various material and post-processing parameters (infiltration and baking) are prepared and studied. Using a statistical experiment design, the mechanical (flexural and compressive strength) and thermal (conductivity and specific capacity) characteristics are quantified. Findings Relative to the unprocessed “green” print samples, post-processing improved the flexural and compressive strength of the samples by factors of 6.9 and 21.6, respectively; the thermal conductivity and specific heat capacity were improved by factors of 7.7 and 1.2, respectively. For the investigated temperature range (20°C–200°C), the “green” prints showed excellent stability while the stability of post-processed samples depended on the infiltrate used. Microscopic images of the microstructures offered evidence to support improvement in the mechanical and thermo-physical characteristics of the 3D printed sand elements. Research limitations/implications The literature review concluded that optimal printing parameters and infiltration under vacuum could further improve the mechanical and thermo-physical properties of the binder jet printed elements. However, both these factors were not explored in this research. The statistical experimental design approach provided more flexibility to choose the number of experiments for a fixed amount of time and resources. However, for future work, a more extensive number of experiments and reproducibility testing for each combination of binder-infiltrate is recommended. Practical implications 3D printing has been identified as a promising opportunity to reduce material usage and improve construction efficiency in the field of architecture and building engineering. The emerging fabrication technologies are further expected to significantly reduce the operational energy of buildings through performance integration, i.e. multi-functional building elements with integrated heat- and mass-transfer capabilities to replace conventional systems. Originality/value This study has quantified the impact of infiltration on the mechanical and thermo-physical characteristics of sand-printed elements and, as such, reports reproducible functional performance maps for sand-print applications. The research demonstrates a way to achieve the desired functional characteristics of 3D prints through combinations of material selection and process/post-processing parameters.


2009 ◽  
Vol 39 (2) ◽  
pp. 237-272 ◽  
Author(s):  
Oron Shagrir

The thesis that mental properties are dependent, or supervenient, on physical properties, but this dependence is not lawlike, has been influential in contemporary philosophy of mind. It is put forward explicitly in Donald Davidson's seminal ‘Mental Events.’ On the one hand, Davidson claims that the mental is anomalous, that ‘there are no strict deterministic laws on the basis of which mental events can be predicted and explained’ (1970, 208), and, in particular, that there are no strict psychophysical laws. On the other hand, he insists that the mental supervenes on the physical; that ‘mental characteristics are in some sense dependent, or supervenient, on physical characteristics’ (1970, 214).


Author(s):  
Adilson Martins de OLIVEIRA JUNIOR ◽  
Cláudia Scoton Antonio MARQUES

Com o desenvolvimento dos grandes centros urbanos e o aumento das áreas impermeáveis, surge a necessidade de aumentar as áreas permeáveis, sem abrir mão do pavimento de concreto e ainda assim ajudar na drenagem urbana, tirando a sobrecarga dos sistemas de drenagem tradicionais. Desse modo, o objetivo desta pesquisa é comparar dois traços de concreto permeável com as mesmas características físicas e mesmas compactações, mas tendo como diferença o tipo de cimento a ser empregado que serão o CP II-E e o CP II-Z, ambos com 32 MPa de resistência, com isso serão analisadas quais as mudanças na resistência e na permeabilidade dos corpos de prova que podem ocorrer. Serão moldados em laboratório cerca de 6 corpos de prova para ensaios de resistência à compressão e mais 4 corpos para os ensaios de permeabilidade que seguiram as especificações da NBR 16416 com algumas adaptações e foram cronometrados o tempo que o corpo de prova demorava para absorver certa quantidade de água e usando uma fórmula disponível na mesma norma. Os resultados indicam que não houve diferenças significativas entre os traços comparados, porém a resistência de ambos foram superiores às observadas em outras pesquisas e notou-se que os traços feitos com o CP II-Z tiveram uma ligeira vantagem, mas ainda ficam empatados com o outro traço. No quesito de permeabilidade, ambos têm um ótimo desempenho, pois atendem aos critérios mínimos da NBR 16416. Conclui-se que a comparação entre esses dois cimentos não mostrou tantas diferenças significativas, porém foi observado que a compactação e cura são elementos fundamentais para agregarem resistência aos pavimentos drenantes. Com isso, é possível ampliar o leque de aplicações para que no futuro se possa adotar o pavimento permeável até mesmo em vias públicas e rodovias.   A STUDY OF THE RELATIONSHIP BETWEEN STRENGTH AND HYDRAULIC CONDUCTIVITY OF THE PERMEABLE PAVING ADDED WITH POZZOLAN   ABSTRACT Along with the development of large cities and the increase in impermeable areas, it raises the need for permeable areas expansion without forgoing the concrete paving and after all promoting urban drainage in order to unburden the traditional drainage systems. Accordingly, this study sought to compare two traits of permeable concrete with the same physical characteristics, the same compaction, although they differ in the type of concrete to be applied, they are CP II-E and CP II-Z, both 32 MPa resistant, hence possible changes to occur in strength and permeability of the specimen will be analyzed. In the laboratory, six specimens will be mold for compressive strength testing, and four extra specimens for permeability testing following NBR 16416 standard with some adaptations, we measured the time the specimen takes for absorbing an amount of water, as well as an available formula following the same standards.  The results suggest that there were no significant differences between the traits when compared. However, the strength for both was higher when compared to other studies, it was noticed that traits made with CP II-Z presented a slight advantage, nevertheless, they are similar to the other trait. Regarding permeability, both had a great performance, since they meet the minimum NBR 16416 standards. We concluded that the comparison between those concretes had not presented significant differences, though we observed that compaction and drying are key elements to add strength to draining concrete paving. Hence, it is possible to broaden applications in order to adopt permeable paving even for public roads and highways.   Keywords: Permeable paving. Drainage. Concrete.


2013 ◽  
Vol 647 ◽  
pp. 133-138
Author(s):  
Di Wu ◽  
Jian Hua Wen ◽  
Li Hua Li ◽  
Yao Wu Zhao ◽  
Bo Li ◽  
...  

To mimic the alveolar bone and periodontal ligament interface, a chitosan(CS for short) composite polysaccharide scaffold was fabricated which was cross-linked with sodium alginate(SA for short). The conditions of physical crosslinking in the scaffolds were discussed. By characterization after biomineralization, it turns out that pH=5.0 and 40min crosslinking time can make for crosslinking. Better crosslinking makes the material more antiswelling and give more compressive strength. In the other hand, the biomineralization can improve the physical properties of the material. We hope that after further research it can come to a scaffold material with good properties.


2012 ◽  
Vol 4 (1) ◽  
pp. 1
Author(s):  
Djoko Purwanto

Timber Acacia mangium (Acacia mangium, Willd) for Furniture. The study aims to determine the mechanical and physical properties and the decorative value (color and fiber) wood of acacia mangium with using finishing materials. This type of finishing material used is ultran lasur natural dof ,ultran lasur classic teak, aqua politur clear dof, aqua politur akasia dan aqua politur cherry. After finishing the wood is stored for 3 months. Test parameters were observed, namely, physical and mechanical properties of wood, adhesion of finishing materials, color and appearance of the fiber, and timber dimensions expansion. The results showed that the mechanical physical properties of acacia wood qualified SNI. 01-0608-89 about the physical and mechanical properties of wood for furniture, air dry the moisture content from 13.78 to 14.89%, flexural strength from 509.25 to 680.50 kg/cm2, and compressive strength parallel to fiber 342.1 - 412.9 kg/cm2. Finishing the treatment process using five types of finishing materials can increase the decorative value (color and fiber) wood. Before finishing the process of acacia mangium wood has the appearance of colors and fibers and less attractive (scale scores 2-3), after finishing acacia wood fibers have the appearance of colors and interesting and very interesting (scale 4-5).Keywords: mangium wood, mechanical properties, decorative value, finishing, furniture.


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