Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efficiency (IWUE) of summer squash responses to different irrigation quantities were evaluated with a field study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefficients (Kcp1: 1.0; Kcp2: 0.85 and Kcp3: 0.70). Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield (80.0 Mg ha-1) was determined in the Kcp1 treatment, which applied the highest volume of irrigation water (452.9 mm). The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 Mg ha-1 , 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment (176.6 kg ha-1 mm-1) it was statistically similar to the value for Kcp3 treatment (157.1 kg ha-1 mm-1). Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 (44.27 µg GAE/mg fresh sample) and in the Kcp2 (84.75%) treatments, respectively. Major (Na, N, P, K, Ca, Mg and S) and trace (Fe, Cu, Mn, Zn and B) mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were significantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be most suitable due to the high fruit quality and relatively high yield in water shortage conditions.

The use of mineral admixtures and industrial waste as a replacement for Portland cement is recognized widely for its energy efficiency along with reduced CO2 emissions. The use of materials such as fly ash, blast-furnace slag or limestone powder in concrete production makes this process a sustainable one. This study explored a number of hardened concrete properties, such as compressive strength, ultrasonic pulse velocity, dynamic elasticity modulus, water absorption and depth of penetration under varying curing conditions having produced concrete samples using Portland cement (PC), slag cement (SC) and limestone cement (LC). The samples were produced at 0.63 and 0.70 w/c (water/cement) ratios. Hardened concrete samples were then cured under three conditions, namely standard (W), open air (A) and sealed plastic bag (B). Although it was found that the early-age strength of slag cement was lower, it was improved significantly on 90th day. In terms of the effect of curing conditions on compressive strength, cure W offered the highest compressive strength, as expected, while cure A offered slightly lower compressive strength levels. An increase in the w/c ratio was found to have a negative impact on pozzolanic reactions, which resulted in poor hardened concrete properties. Furthermore, carbonation effect was found to have positive effects on some of the concrete properties, and it was observed to have improved the depth of water penetration. Moreover, it was possible to estimate the compressive strength with high precision using artificial neural networks (ANN). The values of the slopes of the regression lines for training, validating and testing datasets were 0.9881, 0.9885 and 0.9776, respectively. This indicates the high accuracy of the developed model as well as a good correlation between the predicted compressive strength values and the experimental (measured) ones.

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This study aims to produce alkali-activated materials (AAM) under different curing conditions using a ceramic powder (CP) instead of a blast furnace slag (BFS) and a micro calcite (McK) instead of a calcareous aggregate. The water/binder (W/B) ratios of the AAMs range from 0.30-0.42 and the sodium silicate (SS) ratios range from 15-60 %. They were subjected to curing process in 80°C water and in an oven, in the air, and with a chemical curing method. Consequently, it was observed that an increase in the ratios of SS and W/B and using 25 % McK with a spherical structure, increased the workability. An increase in the CP and McK usage ratios reduced the 28-day compressive strengths. Using the CP while designing the AAMs, which were exposed to sodium sulfate and sulfuric acid, reduced the losses in strength. Also, an increase in the CP ratio has a positive influence on the AAM as it increases the high-temperature endurance of the mortars. For conventional concrete, permeability in freeze-thaw resistance is an important factor for AAMs. Hence, using McK in AAMs increases the freeze-thaw resistance. Consequently, it was observed that using a CP up to 40 % influences the AAM positively.

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