The motivation of this study is to promote sustainability in the construction and mining industries from a research perspective, considering the CO2 emissions associated with cement production and the use of mining waste materials, such as copper tailings, as supplementary cementitious materials. In this study, copper tailings partially replaced cement as received between 0 to 50 wt.%. Mortar and reinforced mortar samples were manufactured for mechanical and corrosion analysis. The mechanical tests revealed that the maximum compressive and flexion strengths were maintained by adding copper tailings, which were delayed for a longer exposure time, possibly due to the hydration reaction. Morphological analysis revealed that the partial cement replacement increased the porosity in the mortar at earlier stages, which was similar for longer exposure time. In addition, electrochemical impedance spectroscopy allowed in-situ monitoring of the mortar\'s evolution and mortar/steel interface. The impedance response showed that partial cement replacement with 15 wt. % of copper tailings as received can improve steel passivation after prolonged exposure. Therefore, cement replacements can be a suitable solution to produce reinforced mortars.
This systematic review and meta-analysis aimed to assess the impact of contamination with eugenol-containing or eugenol-free temporary cement on the bond strength of self-adhesive resin cement. A comprehensive electronic search was conducted across Pubmed, Scopus, and ISI databases without language or publication date restrictions, up to August 18, 2020. Eligible studies were in vitro investigations measuring the bond strength of self-adhesive cement after contamination with eugenol-free or eugenol-containing provisional cement. Articles were categorized based on the type of temporary cement (with or without eugenol), and the effect size was presented as the standardized difference in means (SDM) between the intervention and control groups. A random-effects model was employed for the meta-analysis. Out of 450 initially identified articles, four met the inclusion criteria. The results indicated a significant reduction in the bond strength of self-adhesive cement when the temporary restoration was adhered with either eugenol-containing (SDM = -1.64, P < 0.001, I2 = 48.48%) or eugenol-free (SDM = -1.33, P < 0.001, I2 = 61.68%) provisional cement, compared to the control group. Contamination with temporary cement, regardless of eugenol presence, diminishes the bond strength of self-adhesive cement. It appears that the residue of temporary cement is a more critical factor than the presence or absence of eugenol in weakening the bonding quality of permanent cement to the tooth substrate.
Space colonisation will depend on our capacity to sustain a crew\'s metabolic demands (food, water, and oxygen) on a regular basis with little to no replenishment from Earth. Plant crops are cultivated on earth to support these tasks, hence developing plant-based food production systems is crucial in maintaining humankind\'s existence in space. For thousands of years, farming methods have changed on Earth to satisfy the needs of a growing population and the scarcity of resources. Currently, these methods need to change to account for the effects of global warming. Space farming is the practice of cultivating crops for food and other uses in space or on alien planets. Food supply to space stations and other long-term missions requires a lot of labour and money. The cost of refilling and the difficulties of resupplying interplanetary trips make the idea of manufacturing food in flight quite appealing. To supply water, nutrients, and oxygen to the plant roots, specialised space greenhouses use controlled release fertiliser, a porous clay base, and LED illumination. Comprehending the growth responses of plants to space-specific restrictions including changed gravity, ionising radiation, and constrained volume is essential, in addition to understanding the growth responses to all environmental elements that act on Earth. It is also necessary to modify farming methods in light of these constraints. The nature and degree of environmental aspects that need to be considered are contingent upon the specific mission situations. This paper deals with the historical perspective, need and basic concepts of space farming. It also provides insights on the impacts of space factors on plants and types of space farms.
This study investigates the effects of climate change on the diversity of alpine flora in the European Alps. Over the past two decades, data was collected from various altitudes and regions, analyzing shifts in plant species distribution and abundance. The research employs a combination of field surveys, remote sensing, and climate modeling to understand the impact of rising temperatures and changing precipitation patterns. Results indicate a significant shift in species composition, with some species migrating to higher altitudes while others face increased risk of extinction. This study underscores the importance of adaptive conservation strategies to preserve alpine biodiversity.
This study examines the impact of climate change on the diversity and growth patterns of alpine flora in the European Alps. By analyzing temperature and precipitation data alongside plant phenology, we assess how alpine plant species are adapting to changing environmental conditions. Our findings indicate a shift in flowering times and species distribution, highlighting the resilience and vulnerability of alpine ecosystems. The study emphasizes the importance of conservation efforts to preserve biodiversity in these sensitive habitats.
The present study basically deals with the construction of the small pond in particular and the water filtration in general in Choghazanbil which is considered the valuable memorial of Ilam civilization constructed near Susa, Khouzestan. According to the reliable views, there are two hypotheses about this small pond. 1. The existence of multiple drain pipes shows that Ilamian paid attention to the necessity of protection system and water discharging with regard to the material quality and the weather of that time 2. When the bigger pond became full of water and the water level became on the same level with the margin of its ending wall, according to the related containers rules, the water's mires will sediment. In this study, with physical considerations, the potential capability of the pond to produce high quality water is proved. According to historical states of Choghazanbil site and archeology excavations; with combining two hypotheses, the real performance of two ponds is filtering discharged surface waters.
Urban green spaces play a crucial role in enhancing biodiversity within city landscapes. This study examines the biodiversity present in various green spaces across Paris, highlighting the importance of these areas in supporting urban ecosystems. Through field surveys and data analysis using GIS and remote sensing technologies, we identified key factors that influence biodiversity levels, such as size, vegetation type, and proximity to other natural habitats. The findings emphasize the need for integrative urban planning strategies that prioritize green space conservation to foster biodiversity in metropolitan environments.
Urban green spaces are vital components of city landscapes, offering numerous benefits such as biodiversity enhancement, climate regulation, and recreational opportunities. This study investigates the role of urban parks and gardens in supporting biodiversity and providing ecosystem services. By comparing green spaces in three major cities—London, Tokyo, and Nairobi—we assess species diversity, carbon sequestration, and public health impacts. Our findings suggest that diverse plantings and habitat structures significantly improve biodiversity and ecosystem service delivery. The research highlights the need for strategic urban planning to integrate green infrastructure for sustainable city development.
A simple, highly sensitive, accurate and selective method for determination of trace amounts of Pb(II) in water samples is presented. A novel Schiff base-chitosan-grafted multiwalled carbon nanotubes (S-CS-MWCNTs) solid-phase extraction adsorbent was synthesized by covalently grafting a Schiff base-chitosan (S-CS) onto the surfaces of oxidized MWCNTs. The stability of the chemically modified (S-CS-MWCNTs) was evaluated, especially in concentrated hydrochloric acid, which was then used as a recycling and pre-concentration reagent for further uses. The method is based on selective chelation of Pb(II) on surfactant coated C18, modified with a Schiff base-chitosan-grafted multiwalled carbon nanotubes (S-CS-MWCNTs). The retained ions were then eluted with 4 ml of 4 M nitric acid and determined by flame atomic absorption spectrometry (FAAS) at 283.3 nm for Pb. The influence of flow rates of sample and eluent solutions, pH, breakthrough volume, effect of foreign ions on chelation and recovery were investigated. 1.5 g of surfactant coated C18 adsorbs 40 mg of the Schiff’s base which in turn can retain 15.0±0.9 mg of each of the two ions. The limit of detection (3σ) for Pb(II) was found to be 3.20 ng l -1. The enrichment factor for both ions is 100. The mentioned method was successfully applied for the determination of lead in different water samples. The ions were also speciated by means of a three-column system.
Mismatch negativity (MMN) was used to investigate the processing of cluster and noncluster initial consonants in consonant-vowel syllables in the human brain. The MMN was elicited by either syllable with cluster or noncluster initial consonant, phonetic contrasts being identical in both syllables. Compared to the noncluster consonant, the cluster consonant elicited a more prominent MMN. The strong MMN peaks at ~128 ms after change onset in cluster-to-noncluster initial consonants changes and at ~212 ms in noncluster-to-cluster initial consonants changes. The significantly different neuronal populations were thus active between 128-212 ms when syllables with cluster and noncluster initial consonants were present. Microstate segmentation analyses showed that the phonological perception for cluster consonant was at 212 ms whereas 128 ms for non-cluster consonant. After approximately 220 ms, semantic perception started in order to perceive the meaning of the words.
