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Determining the water permeability of concrete in structures remains a challenge because of difficulties in removing the influence of its moisture content. Saturating concrete with water could be one option, but this is not easy to achieve on site. This paper reports a testing programme carried out to assess the reliability and effectiveness of two field saturation methods, viz. vacuum saturation and ponding. The water permeability test results after applying the vacuum saturation and ponding were compared with that obtained after incremental immersion. It was found that ponding was unable to remove the influence of moisture, whilst vacuum saturation was effective for wet concretes. The results obtained from the electrical resistance measurements after incremental immersion suggested that the water permeability of concretes can be accurately determined by carrying out in situ permeability tests if the near surface region up to a depth of 25 mm is fully saturated.

Several techniques or capabilities are provided by DirectX, each of whichcan add effects on the designed graphics by using special functions in theapplication or program that written to design that graphics. Some of thesecapabilities are that, Lighting, Rotation, Texturing, Fog, Environment Mappingand Stencil Buffer capabilities.In this research, implementation of two capabilities are produced, the firstimplementation is of the Texturing capability and show several states of texturingby using variables values of tu and tv texture coordinates.The second implementation is of the Environment Mapping capability whichshows how a shiny teapot is rotated and only one face of the skybox is reflected byit.DirectX can be written in many programming languages, such as C, C++,Visual C++, and Visual Basic.When using the DirectX capabilities in many applications, not all cardssupport all that capabilities at the implementation time, some of these likeLighting, Rotation and Texturing capabilities can be implemented with 64-MegaByte VGA cards, but others like Fog, Environment Mapping and Stencil Buffercapabilities are implemented with 128-Mega Byte and over.

A new series of β-ketoesters in which the keto group is attached to the olefinic linkage were synthesized by the reaction of methyl acetoacetate and aromatic aldehydes under specified conditions. The existence of these compounds predominantly in the intramolecularly hydrogen bonded enol form was well demonstrated from their IR, 1H-NMR and mass spectral data. Details on the formation of their [ML2] complexes with Ni(II), Cu(II) and Zn(II) and the nature of the bonding are discussed on the basis of analytical and spectral data.

The coupling of diazotized 1-aminonaphthalene with 1,3-dicarbonyl compounds (acetylacetone, methylacetoacetate and acetoacetanilide) yielded a new series of bidentate ligand systems (HL). Analytical, IR, 1H-NMR and mass spectral data indicate that the compounds exist in the intramolecularly hydrogen bonded keto-hydrazone form. With Ni(II), Cu(II) and Zn(II), these potential monobasic bidentate ligands formed [ML2] type complexes. The IR, 1H- -NMR and mass spectral data of the complexes are consistent with the replacement of the chelated hydrazone proton of the ligand by a metal ion, thus leading to a stable six-membered chelate ring involving the hydrazone nitrogen and the hydrogen bonded carbonyl oxygen. The Ni(II) and Zn(II) chelates are diamagnetic, while the Cu(II) complexes are paramagnetic. In the metal complexes of the naphthylazo derivatives of acetylacetone and methylacetoacetate, the acetyl carbonyl is involved in coordination, whereas in the chelates of the naphthylazo derivative of acetoacetanilide, the anilide carbonyl is bonded with the metal ion.

Two new Schiff bases containing olefinic linkages have been synthesized by condensing aliphatic diamines with dicinnamoylmethane under specified conditions. The existence of these compounds predominantly in the intramolecularly hydrogen bonded keto-enamine form was well demonstrated by their IR, 1H-NMR and mass spectral data. Dibasic tetradentate N2O2 coordination of the compounds in their [ML] complexes (M = Ni(II), Cu(II) and Zn(II)) was established on the basis of analytical and spectral data.

Phenylazo- and thiazolylazo-2,4-pentanediones on reaction with 2-aminophenol and 2-aminothiophenol yielded a new series of polydentate Schiff’s base ligands. The structure and tautomeric nature of these compounds and their metal complexes were established on the basis of their IR, 1H-NMR and mass spectral data. The spectral and analytical data revealed the condensation of both carbonyl groups of 3-(2-thiazolylazo)- 2,4-pentanedione with 2-aminophenol to form an N2O2 tetradentate ligand. Details on the formation of its [ML] complexes with Ni(II), Cu(II) and Zn(II) and the nature of their bonding are discussed based on analytical, IR, 1H-NMR and mass spectral data.

This study examines the potential of using calcium‐rich precursors to improve the strength of alkali‐activated slag (AAS) cement at low temperature. To achieve this target, the effect of calcium‐rich precursors on the early strength development of AAS mortars cured at 5°C was assessed. The strength development was investigated along with its internal temperature, microstructure and reaction products. It is found that the calcium‐rich precursors can improve the early strength of AAS around 35% and the group with Portland cement clinker gave the highest strength. Calcium oxide can also increase the compressive strength of AAS cement, but its effectiveness is not as good as the sample with clinker. Adding calcium sulfoaluminate can increase the early strength, while no significant contribution to 28‐day strength could be found. The results highlight that compressive strength of modified AAS mortar can reach 15 MPa at 6 h and 20 MPa at 24 h at 5°C, suggesting that this binder could be a valuable alternative for low temperature construction. [ABSTRACT FROM AUTHOR]

Clustering is a common method for finding patterns in underlying data in data mining applications. The majority of conventional clustering methods are restricted to datasets with numeric or categorical characteristics. In real-world data mining applications, however, datasets containing various kinds of characteristics are frequent. To address this issue, we offer a new divide-and-conquer strategy in this article. To begin, the original mixed dataset is split into two sub-datasets: pure category and pure numeric. Then, to generate matching clusters, existing well-established clustering algorithms intended for various kinds of datasets are used. The superiority of our method is shown by comparisons with existing clustering algorithms on real-world datasets. Clustering is a well-known data mining method for pattern detection and retrieval of information. The data in the first clustering dataset may be categorised or numerical. Each kind of data has its own method for clustering. The k-means method for clustering numeric datasets and the k-modes technique for categorical datasets are proposed in this area. The transformation of categorical characteristics into numeric measurements and direct application of the k-means algorithm instead of the k-modes method is one of the major issues in achieving the clustering process on categorical values. In this article, it is suggested to test a method based on the preceding problem, which involves converting categorical data into numeric values by utilising the relative frequency of each modality in the characteristics. [ABSTRACT FROM AUTHOR]

Byline: W. John McCarter, Thomas M. Chrisp, Gerry Starrs, Muhammed Basheer Currently, the most predominant process associated with the deterioration of reinforced concrete structures is corrosion. Since it is the cover-zone concrete which protects the steel from the environment, the ability to study the protective qualities of the covercrete could assist in assessing the current and future performance of the structure. To this end, a multi-electrode array was used to study the surface 50 mm of concrete specimens, thereby, allowing a detailed picture of the response of the covercrete to the changing environment, both in the short- and long-term. In the current work, CEM I, CEM II/B-V and CEM III/A cements were used and comprised field studies on both 'mini slabs' and monoliths.

Determining the water permeability of concrete in structures remains a conundrum because of difficulties in removing the influences of moisture. This study describes the extended flow-net theory developed on the basis of the two-pressure-head concept, which provides a means of measuring permeability under the partially saturated condition. Surface-mounted tests and standard laboratory water penetration tests were carried out to verify this approach. Before determining the water permeability, steady-state flow rates at two different pressure levels were evaluated and the effects of initial moisture conditions on flow behavior were investigated. The results indicate that the proposed approach does offer a useful means of determining the water permeability of structural concrete, although it cannot be claimed to be universally applicable for all moisture conditions likely to be encountered in practice. [ABSTRACT FROM AUTHOR]