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The impacts of different replacement levels of micro silica (MS), fly ash (FA), and the combined usage of MS and FA on the behavior of concrete were investigated. Design of experts has been used incorporating the response surface methodology to find the synergetic effect of FA and MS on fresh and hardened concrete properties. A total of 15 and 30% of the binder content were replaced by FA. As well as a total of 5 and 10% of the binder content were replaced by MS. Experimental results of concrete mixtures have been used to construct ANOVA models. These models have also been confirmed to expect the properties of concrete mixtures based on different fractions of FA ash and MS. All statistical models are significant because P-value is less than 5%, and the difference between predicted R 2 and adjusted R 2 is lower than 20%. The variation between confirmation tests for the optimized mixture and test results are lower than 5%.

The present research studies the effect of adding sugar factory waste sugarcane molasses as an alternative to chemical inhibitory additives manufactured on concrete cast during hot weather in the summer of Iraq. The current study includes a study of the setting time for cement paste and workability for fresh concrete and some mechanical properties of hardened concrete with sugarcane molasses using percentage 0–0.3% of cement weight. The study also included studying the value of pH of concrete to investigate the effect of sugarcane molasses on reinforced concrete. The results showed that the sugarcane molasses can be used by about 0.1% of cement weight for medium projects and between 0.1 and 0.2% for large projects. It was also found that the compression strength increased by about 11.5% and the indirect tensile strength increased by about 7.5 and 7.4% for splitting and flexural test, respectively for concrete mixtures containing 0.2% of sugarcane molasses. [ABSTRACT FROM AUTHOR]

This article presents a mathematical model developed using the M5P tree to predict the shear strength of steel-fiber-reinforced concrete (SFRC) for slender beams using soft computing techniques. This method is becoming increasingly popular for addressing complex technical problems. Other approaches, such as semi-empirical equations, can show known inaccuracies, and some soft computing methods may not produce predictive equations. The model was trained and tested using 332 samples from an experimental database found in the previous literature, and it takes into account independent variables such as the effective depth d, beam width bw, longitudinal reinforcement ratio ρ, concrete compressive strength fc, shear span to effective depth ratio a/d, and steel fiber factor Fsf. The predictive performance of the proposed M5P-based model was also compared with the one of existing models proposed in the previous literature. The evaluation revealed that the M5P-based model provided a more consistent and accurate prediction of the actual strength compared to the existing models, achieving an R2 value of 0.969 and an RMSE value of 37.307 for the testing dataset. It was found to be a reliable and also straightforward model. The proposed model is likely to be highly helpful in assessing the shear capacity of SFRC beams during the pre-planning and pre-design stages and could also be useful to help for future revisions of design standards.

This study targeted to investigate a type of excavation slurry by local available material in Najaf region. On the other hand, chief practises is supported the deep sides of foundation in particular pile foundation and, drilling oil wells. The results of slurries are checking, for seven properties, which includes the viscosity (apparent plastic and funnel Marsh), yield stress, density, acidity, and gel power (10–0 min). Which are 11.7367, 8.8733, 38.1667, 11.5467 mPa·s, 1.1045 kg m−3, 10.9067, and 11.2683 mPa·s, respectively. On the basis of the results tests for the above properties, that is possible to produce a product that conforms to the specifications of American Petroleum Institute specifications, and according to the requirements of the standard ACI 336.3R-93:2006 without additives. The rheological behavior improvement is achieved through the breakdown of the bundles of palygorskite fibers that normally make up the texture of these mudstones by increasing the time and speed of the shear force as soon as increasing the concentration of clay powder. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) defines as a self-curing agent when it forms films prevent evaporation water required to hydration. In this study was found the effect of self-curing factor on some mechanical properties is studied by adding of PVA solution to cement ratio (P/C) with varying conditions of curing. The PVA dissolved in water from 1% by weight of cement. It was seen that PVA could service by self- curing through providing increase strength compare with traditional curing. The results showed increased percentages of flexural, tensile and compressive strength of cement mortars with PVA as self-curing agent under dry condition for 28 days were 62%, 101%and 1.5% respectably to compare with self-curing for cement mortars composite modified with PVA as curing agent under wet curing conditions as soon as cement mortars composite modified without PVA were 110%, 5%and14.5% respectably in dry condition also 48 %, 55%and 41% in wet curing conditions respectably. The use of Fourier Transforms Infrared (FTIR) spectra and techniques like scanning electron microscope (SEM) is very significant to show the impacts of the existence of PVA as water-soluble polymer in the fine structure of modified cement mortar by polymers.

Polyvinyl alcohol (PVA) defines as a self-curing agent when it forms films prevent evaporation water required to hydration. In this study was found the effect of self-curing factor on some mechanical properties is studied by adding of PVA solution to cement ratio (P/C) with varying conditions of curing. The PVA dissolved in water from 1% by weight of cement. It was seen that PVA could service by self- curing through providing increase strength compare with traditional curing. The results showed increased percentages of flexural, tensile and compressive strength of cement mortars with PVA as self-curing agent under dry condition for 28 days were 62%, 101%and 1.5% respectably to compare with self-curing for cement mortars composite modified with PVA as curing agent under wet curing conditions as soon as cement mortars composite modified without PVA were 110%, 5%and14.5% respectably in dry condition also 48 %, 55%and 41% in wet curing conditions respectably. The use of Fourier Transforms Infrared (FTIR) spectra and techniques like scanning electron microscope (SEM) is very significant to show the impacts of the existence of PVA as water-soluble polymer in the fine structure of modified cement mortar by polymers. [ABSTRACT FROM AUTHOR]

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Simple phenolic (SP) compounds are natural products that exhibit multiple pharmacological functions. The best known of these compounds is ß-D-salicin, the first discovered phenolic glycoside and salicylic acid, or 2-hydroxybenzoic acid (2-HBA). Both of these compounds have attracted the interest of scientists in various interdisciplinary fields, including chemistry, pharmacology and medicine. Although ß-D-salicin is found in various plants, it is often associated with willow, as it was first discovered in this species of plant. While the presence of glucose in ß-D-salicin improves the physicochemical properties of the benzyl moiety, ß-D-salicin itself does not have anti-inflammatory or anti-proliferative activity until it is metabolised into 2-HBA in the gastrointestinal tract and blood stream. Likewise, the majority of 2-acetoxybenzoic acid (2-ABA), or acetoxysalicylic acid also undergoes metabolic hydrolysis into 2-HBA. 2-HBA has been shown to play a role in modulating both inflammation and cancer partly through the inhibition of cyclooxygenase-2 (COX-2). It is now clear that 2-HBA most likely acts on the transcription factor NF-KB, which regulates the transcription of COX-2 thereby suppressing inflammation and cell proliferation and promoting apoptosis. Other phenolates, also exhibit anti-inflammation and anti-proliferation activities like the 4-hydroxybenzoate zinc (4-HBZn) complex, which was previously shown to preferentially inhibit COX-2 compared to 2-HBA and ASA. This review aims to collect all the available information related to ß-D-salicin and other SP compounds in order to promote a new perspective of this interesting class of compounds and encourage further research into their pharmacological and clinical properties. [ABSTRACT FROM AUTHOR]

Action Research Essentials by Dorothy Valcarcel Craig (2009) is an excellent resource for the emerging researcher; especially doctoral students in their first year of studies. Craig is successful in providing the reader with the essentials of action research while also addressing common challenges; one baby step at a time. In this review I will first explain the process of selecting and conducting the first reading of the book followed by identifying the author's objectives and intent. Then, I present a brief description of each chapter and note how their content relates to struggling research students' common challenges of the . I then put forth a quantitative description of one of the major strengths of the book, followed by online resources associated with each chapter. [ABSTRACT FROM AUTHOR]