The need for global energy conservation has become more urgent because of the negative effects of excessive energy use, such as higher fuel consumption, greater environmental pollution, and depletion of the ozone layer. There has been a significant increase in the demand for central and high-capacity household air conditioning systems in Muscat in recent years. The need for this is influenced by factors such as arid climate, increasing temperatures, air pollution, and population increase. As a result, there has been a significant increase in electricity use, putting a strain on power resources. To tackle this difficulty, the incorporation of solar collectors as supplementary thermal compressors in air conditioning systems offers a chance to utilise renewable energy sources. The objective of this hybrid technique is to enhance the effectiveness of cooling systems, hence minimising the need for electricity and lowering the release of environmental pollutants.

The interest in smart grids and new technologies is growing around the world. Countries are investing in the development of new technologies that will help achieve environmental goals, energy supply efficiency, improve energy efficiency and increase consumer involvement in the energy generation. One of such technology is a blockchain. It is believed that the blockchain, combined with a smart grid, provides an opportunity to integrate the activities of all stakeholders, including: generators, distributors and consumers of electricity. The aim of the article is to identify the key research areas discussed by the researchers of both the smart grid and the blockchain issues. An analysis of the Scopus database from 2015 to 2023 was conducted. Using a created bibliometric query, a systematic literature review was conducted. 476 scientific publications relating to the issues addressed were identified. Using the VOSviewer software, a bibliometric analysis was performed using the author’s keywords. The bibliometric maps obtained allowed for the identification of key research areas. The article also presents potential future directions of scientific considerations, which should be focused on the issue of green smart grid and green blockchain. The results presented in the article can inspire researchers looking for research gaps or describing the current state of knowledge in the field of the smart grid and the blockchain issues.

Herein, we report a facile preparation of super-hydrophilic sand by coating the sand particles with cross-linked polyacrylamide (PAM) hydrogels for enhanced water absorption and controlled water release aimed at desert agriculture. To prepare the sample, 4 wt% of aqueous PAM solution is mixed with organic cross-linkers of hydroquinone (HQ) and hexamethylenetetramine (HMT) in a 1:1 weight ratio and aqueous potassium chloride (KCl) solution. A specific amount of the above solution is added to the sand, well mixed, and subsequently cured at 150 °C for 8 h. The prepared super-hydrophilic sands were characterized by Fourier-transform infrared spectroscopy (FT-IR) for chemical composition and X-ray diffraction (XRD) for successful polymer coating onto the sand. The water storage for the samples was studied by absorption kinetics at various temperature conditions, and extended water release was studied by water desorption kinetics. The water swelling ratio for the super-hydrophilic sand has reached a maximum of 900% (9 times its weight) at 80 °C within 1 h. The desorption kinetics of the samples showed that the water can be stored for up to a maximum of 3 days. Therefore, super-hydrophilic sand particles were successfully prepared by coating them with PAM hydrogels, which have great potential to be used in sustainable desert agriculture.

As the technical support for economic activities and social development, standards play a great role in modern society. However, with the increasing digitization of various industries, the traditional form of standards can no longer meet the needs of the new era, and there is an urgent need to digitally transform standards using advanced technologies. The digital transformation of standards involves the standard itself and all stages of its life cycle, is a very complex systematic project, in the transformation process, technology plays a key role. Therefore, this paper summarizes the key technologies involved in the process of digital transformation of standards, sorted out and evaluated them according to different purposes for which they were used, while giving the digitalization of standards transformation technology development trends and planning as well as typical cases, hoping to provide a comprehensive and clear perspective for those engaged in the related work, as well as reference for the subsequent research and application of digital transformation of standards.

Objective: To evaluate the radiographic characteristics of dentigerous cysts (DC) diagnosed at the School of Stomatology of the Universidad Peruana Cayetano Heredia (UPCH) during the period of 2010–2017. Material and methods: Retrospective, descriptive, observational and cross-sectional study, where the panoramic radiographs of 37 cases of DC were selected. Results: The total number of diagnosed cases of dentigerous cysts was 233, which after inclusion and exclusion criteria, 37 cases were obtained, of which 45.9% of cysts were found in the second decade of life with a higher frequency of 51.4 percent for women, and a jaw predilection of 59.5% in all cases. In addition, it was found that 97.3% of the cases were radiolucent, defined limits were found in 67.6%, corticalized edges in 54.1% and unilocular in 94.6%. All dentigerous cysts were associated with a tooth, of which closed apex (48.6%) and tooth displacement (59.5%) were observed. The adjacent tooth was not affected in 56.8% of cases, but its hard lamina was affected (59.5%). The 68.2% of cases did not affect the basal mandibular cortex, but did displace the inferior dental canal (54.5%) and 46.7% of cases displaced the floor of the maxillary sinus. Conclusions: Most of the results obtained on the characteristics in the Peruvian population support previous studies reported in America, Europe and Asia. Radiographically the dentigerous cyst showed characteristics that support its clearly benign behavior.