Plants provide a wealth of bioactive compounds which aid in exerting a substantial strategy for the treatment of neurological disorders such as Alzheimer's disease and dementia.

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The purpose of this research carried out in 2018 under Eskişehir ecological conditions was to determine the effect of six different harvest dates (T1: 16 August, T2: 29 August, T3: 14 September, T4: 28 September, T5: 15 October and T6: 31 October) on the yield and quality properties rosemary (Rosmarinus officinalis L.). The experiment was established according to a randomized complete-block design with four replications. The composition of the essential oil obtained by the hydro-distillation from the dry leaves of the rosemary plant was analyzed by GC-MS. In the experiment carried out, the mean values of plant height (cm), fresh herb yield (t ha -1 ), dry herb yield (t ha -1 ), dry leaf yield (t ha -1 ), essential oil ratio (%), essential oil yield were determined as 61.87 cm, 15.78 t ha -1 , 5.80 t ha-1, 3.55 t ha -1 , 0.69% and 23.92 l ha -1 , respectively. In the essential oil samples obtained from the harvests made at different dates, 35 different components were identified. The values of the camphor, 1-verbenone, α-pinene, borneol and 1,8-cineol components determined as the main component in the analyzed essential oil samples ranged from 11.67 to 14.78%, from 8.47 to 11.77%, from 8.74 to 11.82%, from 8.61 to 11.12% and from 7.01 to 9.07%, respectively.

A successful integration of two independent phases with good adhesion is imperative for effective translation of superior carbon nanofiber filler properties into a physically superior carbon nanocomposite. Carbon nanofibers were subjected to electrochemical oxidation in 0.1 M nitric acid for varying times. The strength of adhesion between the nanofiber and an epoxy matrix was characterized by flexural strength and modulus. The surface functional groups formed and their concentration of nanofibers showed a dependence on the degree of oxidation. The addition of chemical functional groups on the nanofiber surface allows them to physically and chemically adhere to the continuous resin matrix. The chemical interaction with the continuous epoxy matrix results in the creation of an interphase region. The ability to chemically and physically interact with the epoxy region is beneficial to the mechanical properties of a carbon nanocomposite. A tailored degree of surface functionalization was found to increase adhesion to the matrix and increase flexural modulus.

The definition of a nanocomposite material has broadened significantly to encompass a large variety of systems made of dissimilar components and mixed at the nanometer scale. The properties of nanocomposite materials also depend on the morphology, crystallinity, and interfacial characteristics of the individual constituents. In the current work, vapor-grown carbon nanofibers were subjected to varying heat-treatment temperatures. The strength of adhesion between the nanofiber and an epoxy (thermoset) matrix was characterized by the flexural strength and modulus. Heat treatment to 1800 • C demonstrated maximum improvement in mechanical properties over that of the neat resin, while heat-treatment to higher temperatures demonstrated a slight decrease in mechanical properties likely due to the elimination of potential bonding sites caused by the elimination of the truncated edges of the graphene layers. Both the electrical and thermal properties of the resulting nanocomposites increased in conjunction with the increasing heat-treatment temperature.

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Salvia officinalis L. is a medicinal plant extensively used in foods, traditional medicine, and the pharmacological industry. In the current study, the effects of different irrigation regimes [irrigation after 70 ± 5 (regular), 105 ± 5 (moderate drought stress), and 140 ± 5 (severe drought stress) mm evaporation] and nutrient sources (control, NPK, farmyard manure, foliar fertilizer, and hydrogel) were investigated on the growth parameters and essential oil (EO) components of S. officinalis in the greenhouse. The plants were harvested two times. The regular irrigation treatment had the most significant effect on plant height (51 cm), fresh and dry herb weight (51.5 and 18.1 g plant −1 ), and fresh and dry leaf weight (40.1 and 13.1 g plant −1 ). The highest amount of EO was observed after moderate drought stress (1.48%). The NPK treatment had the greatest effect on plant height (40 cm), branch number (19 per plant), fresh and dry herb weight (53.4 and 18.9 g plant −1 ), fresh and dry leaf weight (41.2 and 13.6 g plant −1 ), and EO content (1.67%). The 1 st cutting was superior in EO amount, while the 2 nd cutting had a high agronomic yield. α-Thujone (from 21.6 to 34.2%) was identified as the predominant compound. Additionally, the content of α-thujone in the 2 nd cutting was higher after moderate drought stress, NPK, and hydrogel treatments. Moreover, 1,8-cineole, β-thujone, camphene, α-pinene, α-humulene, viridiflorol, borneol, and bornyl acetate were the other main compounds. As a general result, regular irrigation and NPK treatments improved the agronomic yield of S. officinalis . The plants under drought stress produced high amounts of EO. The farmyard manure also improved plant yield by providing a part of the plant's nutritional needs. Therefore, it could be concluded that it is crucial to determine the effects of limited water availability and various nutrient sources on yield and chemical compositions for medicinal and aromatic plant growth.