Horticulture is a widespread activity in family farming in the Transamazonian region—Pará, with emphasis on production aimed at the family’s own consumption. The lettuce cultivar Vanda (Lactuca sativa L.) represents a significant part of this production, which prioritizes the use of internal labor. The main objective of this work was to evaluate the development of lettuce CV Vanda grown in beds using organic compost and chemical fertilization (NPK). The criteria considered to evaluate this performance were: Root system development, plant height and total fresh mass production. The best averages in relation to root development occurred in the plots cultivated with organic compost in the proportion of 5 kg/m2, due to its characteristics as a fertilizer and soil conditioner. The cultivation with the use of NPK provided the best averages in relation to the production of total fresh mass and plant height, results that were mainly attributed to the extra supply of nitrogen in the covering fertilization, which consisted in the addition of 10 g urea per square meter via soil. Statistical analysis showed no statistically significant difference regarding plant height for both treatments. And in relation to root development, the difference was statistically significant.
The challenge of rural electrification has become more challenging today than ever before. Grid-connected and off-grid microgrid systems are playing a very important role in this problem. Examining each component’s ideal size, facility system reactions, and other microgrid analyses, this paper proposes the design and implementation of an off-grid hybrid microgrid in Chittagong and Faridpur with various load dispatch strategies. The hybrid microgrids with a load of 23.31 kW and the following five dispatch algorithms have been optimized: (i) load following, (ii) HOMER predictive, (iii) combined dispatch, (iv) generator order, and (v) cycle charging dispatch approach. The proposed microgrids have been optimized to reduce the net present cost, CO2 emissions, and levelized cost of energy. All five dispatch strategies for the two microgrids have been analyzed in HOMER Pro. Power system reactions and feasibility analyses of microgrids have been performed using ETAP simulation software. For both the considered locations, the results propound that load-following is the outperforming approach, which has the lowest energy cost of $0.1728/kWh, operational cost of $2944.13, present cost of $127,528.10, and CO2 emission of 2746 kg/year for the Chittagong microgrid and the lowest energy cost of $0.2030/kWh, operating cost of $3530.34, present cost of 149,287.30, and CO2 emission of 3256 kg/year for the Faridpur microgrid with a steady reaction of the power system.
According to the United Nations, by 2050, about 68% of the world’s population will live in urban areas. This population increase requires environmental resilience and planning ability to reduce the negative environmental impacts associated with growth. In this scenario, life cycle analysis, whose standards were introduced by ISO 14000 series, is an essential tool. From this perspective, smart cities whose concern about environmental sustainability is paramount corroborating SDG 11. This study aims to provide a holistic view of environmental technologies developed by Brazilian inventors, focused on life cycle analysis, which promotes innovation by helping cities build greener, more efficient, resilient, and sustainable environments. The methodology of this article was an exploratory study and investigated the scenario of patents in the life cycle. 209 patent processes with Brazilian inventors were found in the Espacenet database. Analyzing each of the results individually revealed processes related to air quality, solid waste, and environmental sanitation. The review of patent processes allowed mapping of the technological advances linked to life cycle analysis, finding that the system is still little explored and can present competitive advantages for cities.
The Cu2–xSe nanoparticles were synthesized by high temperature pyrolysis, modified with aminated polyethylene glycol in aqueous solution and loaded with compound 2,2′–azobis[2–(2–imidazolin–2–yl)propane] dihydrochloride (AIPH). The obtained nanomaterials can induce photothermal effect and use heat to promote the generation of toxic AIPH radicals under the irradiation of near-infrared laser (808 nm), which can effectively kill cancer cells. A series of in vitro experiments can preliminarily prove that Cu2–xSe–AIPH nanomaterials have strong photothermal conversion ability, good biocompatibility and anticancer properties.
Potassium dihydrogen phosphate, KH2PO4 (KDP) crystal is an excellent electro-optical nonlinear optical crystal with large electro-optical nonlinear coefficient, high laser damage threshold, and laser frequency doubling effect, electro-optical effect , Piezoelectric effects and other special features, widely used in inertial confinement fusion engineering (ICF) and electro-optical switching devices. Therefore, its growth mechanism, growth process and performance have been systematically studied. In the process of KDP crystal growth, it is found that the stability of the growth solution is an important factor affecting the quality of crystal growth. Therefore, in recent years, more and more research on the stability of the solution, such as the study of ph, doping, supersaturation, overheating time on the stability of the solution. Among them, the research on the doping is mostly reported, and the research on this aspect is mainly focused on two aspects. On the one hand, it is the study of the stability of the solution under doping, and the other is the effect of doping on the optical quality of the crystal. In fact, the stability of the growth solution and the quality of crystal growth is directly related to the quality, but the existing research to isolate the two researches. Therefore, the experiment will be carried out in the case of double-doped KDP solution stability, KDP crystal growth and crystal optical quality and other experiments, and in-depth analysis of the impact of solution stability and crystal optical quality of the reasons, while the solution stability and The relationship between the optical quality of the crystal is briefly analyzed.
The effects of Zn2+ stress on seed germination, seedling growth and chlorophyll content were studied in order to better understand the effect of heavy metal Zn on the growth and development of green plants. The concentration gradient of Zn2+ was 20, 50,100,150,200,300,500,700mg / L, and deionized water was used as control. The results showed that under the Zn2+ stress condition, the germination index of the rhubarb seeds increased with the increase of Zn2+ concentration. Germination potential, germination rate and germination index were the highest when Zn2+concentration was 100mg / L, the conductivity was the lowest at zinc concentration of 100mg / L, the root length, stem length and chlorophyll content of Zn2+ gradually reduced. The results showed that the amount of Zn2+ could promote seed germination, but the root length, bud length and chlorophyll content of seedlings could be affected by different degrees. The zinc fertilizer should be used in the production.
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