This article describes the synthesis of curcumin complexes with metal ions. Properties of these complexes such as spectra IR and UV-Vis and solubility were investigated. The optimum parameters of ultrasound to enhance the solubility was figured out as follows: the capacity of ultrasound: 750 W/g; the time of ultrasound: 7 min; the concentration of the surfactant Tween 80 : 2%. The maximum solubility (mg/ml) of complexes was as follows: Cur-Fe(III): 0.162 ± 0.01; Cur-Zn(II): 0.267 ± 0.02; and Cur-Ca(II): 0.417 ± 0.05. Antioxidant capacity (DPPH, %I) of curcumin complexes was higher than that of curcumin-free complexes. All of these curcumin complexes revealed antimicrobial activities, in which calcium complex had the best resistance against Salmonella, followed by Fe(III) complexes. Meanwhile, the zinc complex was not resistant to this bacterium. These complexes showed antibacterial activity on Staphylococcus aureus, in which Cur-Ca (II) complexes had the highest antibacterial activity. For Escherichia coli, the Cur-Zn (II) complex had no resistance, while the Cur-Ca (II) complex showed the highest antibacterial activity.

New complexes of 5,11,17,23-tetra[(2-ethyl acetoethoxyphenyl)(azo)phenyl]calix[4]arene (TEAC) with Pb(II) and Cr(III) were prepared in basic solution with a mixture of MeOH and H2O as solvent. The ratio of TEAC and metal ion in complexes was found to be 1 : 1 under investigated condition. The complex formation constants (based on Benesi-Hildebrand method) for TEAC-Pb(II) and TEAC-Cr(III) were 4.03 × 104 and 1.2 × 104, respectively. Additionally, the molar extinction coefficients were 5 × 104 and 1.42 × 104 for TEAC-Pb(II) and TEAC-Cr(III), respectively. The H-Point Standard Addition Method (HPSAM) has been applied for simultaneous determination of complexes formation of Cr(III)/Pb(II) and TEAC with concentration from 2 : 1 to 1 : 20 (w/w). The proposed method was successfully utilized to invest lead and chromium contents in plating wastewater samples. The results for several analyzed samples were found to be in satisfied agreement with those acquired by using the inductively coupled plasma mass spectrometry (ICP-MS) technique.

Among soil pollutants, lead (Pb) is one of the toxic metal pollutants widely used in many industrial processes and occurs as a contaminant in environment. In this study, a field experiment was carried out to investigate the accumulation of lead from soil contaminated by this metal ion on the biomass of some vegetables, including spinach, lettuce, carrots, and potatoes. The results showed that lead was cumulative metal. Besides, the level of lead accumulation in soil of the studied vegetables decreased in the order of tubers of carrots, tubers of potato, spinach root, lettuce root, stems and leaves of spinach, stem and leaves of carrot, stems and leaves of potato, and stem and leaves of lettuce, respectively. Our investigations demonstrate the effect of copper and zinc micronutrient elements which play an important role in the growth and development of plants, on the accumulation of lead from contaminated soil of the studied vegetables. The obtained results showed that high concentration of copper and zinc in soil cause competition with lead in the process of absorption and accumulation in the plant. Specifically, copper and zinc showed the inhibition effect on the uptake and accumulation of lead by these plants.

In this paper, curcumin nano-emulsions were successfully prepared by combining hominization and ultra-sonication methods which have been mentioned. The optimal conditions for the hominization method have been established as follows: 3% emulsifier concentration, 20,000 rpm of capacity in 60 minutes, the average size of nano drops was 78 nm. Meanwhile, the optimal conditions of the ultrasonic method are also constructed as follows: 2% emulsifier concentration, 450 w/g of ultrasonic power, 20 kHz frequency, the average size of the droplet was 58 nm. Nano-emulsion system has been stable after 4 months of cold storage.

Trong bài báo này, bụi mịn PM2.5 sinh ra do quá trình nổ mìn trên mỏ lộ thiên đã được dự báo bởi các mô hình trí tuệ nhân tạo dựa trên mạng nơ-ron truyền thẳng nhiều lớp (Multi-layer Perceptron Neural Network -MLP) và các giải thuật "tối ưu hóa bầy đàn" được cải tiến (Accelerated Particle Swarm Optimization -APSO), giải thuật di truyền (Genetic Algorithm -GA), có tên gọi APSO-MLP và GA-MLP. Các thông số nổ mìn và điều kiện khí tượng đã được xem xét trong nghiên cứu này. Một mạng MLP đã được thiết kế để dự báo nồng độ bụi mịn PM2.5. Các giải thuật tối ưu hóa APSO và GA đã được đưa vào để tối ưu hóa các trọng số của mô hình MLP nhằm cải thiện mức độ chính xác của mô hình MLP truyền thống trong quá trình dự báo. Các kết quả cho thấy cả hai mô hình được phát triển đều có khả năng dự báo nồng độ bụi mịn PM2.5 sinh ra do nổ mìn với mức độ chính xác tương đối cao. Trong đó, mô hình APSO-MLP cung cấp mức độ chính xác cao hơn so với mô hình GA-MLP (RMSE = 5,102; R 2 = 0,900 và MAPE = 0,063). Trong khi đó, mô hình GA-MLP chỉ cung cấp mức độ chính xác với RMSE = 5,331, R 2 = 0,890 và MAPE = 0,073.Từ khóa: Mỏ lộ thiên; Nổ mìn; PM2.5; Mạng nơ-ron nhân tạo; Giải thuật tối ưu; Phát triển bền vững.