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Sorghum [Sorghum bicolor(L.) Moench] is one of the most important forage crops in arid and semiarid regions, and its yield and nutritive value are affected by the harvesting stage. A 2-year field experiment was carried out during the 2017 and 2018 growing seasons to evaluate the forage potential of sorghum cultivars at different harvesting stages. Experimental factors included four harvesting stages (grain milk stage, grain soft dough stage, grain hard dough stage, and grain physiological maturity stage) and seven sorghum cultivars. The highest dry matter and protein yields (38.13 and 3.11 Mg ha−1, respectively) were obtained from cultivar Mashhad-1 at the grain physiological maturity stage, whereas the maximum relative feed value was recorded in cv. Karaj-16 at the grain milk stage. Moreover, the highest crude protein content (116 g kg−1), digestible organic matter (734 g kg−1), and metabolizable energy (2.73 Mcal kg−1) were obtained at the grain milk stage. The maximum panicle dry matter yield (19.39 Mg ha−1) and panicle ratio (552 g kg−1) were found in cv. Karaj-9 at the grain physiological maturity stage. The results of the principal component analysis also showed that with increasing maturity, forage yield increased, and its quality decreased. Overall, when both high forage yield and quality were considered, forage harvesting between the grain soft dough and grain hard dough stages could be recommended. Among the cultivars, the cv. Mashhad-1 with the maximum dry matter and protein yield and high metabolizable energy, digestible organic matter, and crude protein content could be introduced as the superior genotype.

TiO 2 particles with desirable properties were produced by undergoing specific durations of ball milling. Characterizations of the TiO 2 particles before and after ball milling were investigated via X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), particle size analysis, zeta potential, and scanning electron microscope (SEM). The equilibrium adsorption data were well fitted to Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherms. Compared to the as-received TiO 2 (mean particle size d 50 = 0.78 μm, specific surface area = 88.17 m 2 g −1 , pore volume = 0.41 cm 3 g −1 ), the 60 min ball-milled TiO 2 ( d 50 = 0.55 μm, specific surface area = 99.48 m 2 g −1 , pore volume = 0.48 cm 3 g −1 ) enhanced the adsorption quantity of congo red and methylene blue from 10.4 mg g −1 to 13.6 mg g −1 , and from 17.0 mg g −1 to 22.2 mg g −1 , respectively; and also improved the kinetic rates from k = 0.1325 to 0.2193, and k = 0.0944 to 0.1553, respectively. Dye adsorption and degradation efficiency of congo red was enhanced in acidic pH range (2–5.14), and methylene blue was enhanced in alkaline pH range (7.58–12). [ABSTRACT FROM AUTHOR]

In this paper, a robust adaptive sliding-mode control scheme for rigid robotic manipulators with arbitrary bounded input disturbances is proposed. It is shown that the prior knowledge on the upper bound of the norm of the input disturbance vector is not required in the sliding-mode controller design. An adaptive mechanism is introduced to estimate the upper bound of the norm of the input disturbance vector. The estimate is then used as a controller gain parameter to guarantee that the output tracking error asymptotically converges to zero and strong robustness with respect to bounded input disturbances can be obtained. A simulation example is given in support of the proposed control scheme.