Explore the vast range of titles available.

Freshwater resources are scarce in coastal areas, and using seawater as mixing water can alleviate the scarcity of freshwater resources. However, the presence of chloride ions in seawater affects the generation of hydration products and the durability of concrete structures. In order to investigate the effect of hydrated calcium silicate (C-S-H) gel and calcium hydroxide (CH) generation in seawater-mixed cement pastes under 50 °C curing, their microscopic morphology was investigated using differential scanning calorimetry analysis, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The relationship between the amount of C-S-H gel and CH production and the amount of chloride ion dosing, fly ash dosing, and the age of curing were investigated. The degree of influence between hydration products and influencing factors was analyzed using the grey correlation analysis. It was shown that 50 °C curing promoted the hydration reaction and generated more hydration products compared with ASTM standard. The content of C-S-H gel and CH increased with chloride dosage. The content of C-S-H gel increased by 13.5% under 50 °C curing compared with the control group at a chloride dosage of 1.3%. Fly ash is rich in active SiO[sub.2] and AI[sub.2]O[sub.3], and other components, which can react with Ca(OH)[sub.2] generated by cement hydration and then generate C-S-H gel. With the increase of fly ash, the content of C-S-H gel also increases, but the CH content decreases. When 25% of fly ash was doped under 50 °C curing, the C-S-H gel content increased by 5.02% compared to the control group. The CH content decreased by 31.8% compared to the control group. With the growth of the maintenance age, the hydration reaction continues, the generation of C-S-H gel and CH will continue to increase, and their microstructures will become denser. C-S-H gel and CH content increased the most by raising the curing temperature at 7 days of curing, increasing by 10.11% and 22.62%, respectively. C-S-H gel and CH content had the highest gray relation with fly ash dosing. Chloride dosage and age of maintenance had the highest correlation with CH content at room temperature maintenance of 0.788 and 0.753, respectively.

The Na[sup.+]/H[sup.+] antiporter NhaC family protein is a kind of Na[sup.+]/H[sup.+] exchanger from the ion transporter (IT) superfamily, which has mainly been identified in the halophilic bacteria of Bacillus. However, little is known about the Na[sup.+]/H[sup.+] antiporter NhaC family of proteins in the extremely halophilic archaea. In this study, two Na[sup.+]/H[sup.+] antiporter genes, nhaC1 and nhaC2, were screened from the genome of Natronorubrum daqingense based on the gene library and complementation of salt-sensitive Escherichia coli KNabc. A clone vector pUC18 containing nhaC1 or nhaC2 could make KNabc tolerate 0.6 M/0.7 M NaCl or 30 mM/40 mM LiCl and a pH of up to 8.5/9.5, respectively. Functional analysis shows that the Na[sup.+](K[sup.+], Li[sup.+])/H[sup.+] antiport activities of NhaC1 and NhaC2 are both pH-dependent in the range of pH 7.0–10.0, and the optimal pH is 9.5. Phylogenetic analysis shows that both NhaC1 and NhaC2 belong to the Na[sup.+]/H[sup.+] antiporter NhaC family of proteins and are significantly distant from the identified NhaC proteins from Bacillus. In summary, we have identified two Na[sup.+](K[sup.+], Li[sup.+])/H[sup.+] antiporters from N. daqingense.

Heterosigma akashiwo is a unicellular microalga which can cause massive mortality in both wild and cultivated fish worldwide, resulting in substantial economic losses. Environmental parameters such as salinity, light, and temperature showed a significant effect on bloom initiation and the toxicity of H. akashiwo. While in previous studies a one-factor-at-a-time (OFAT) approach was utilized, which only changes one variable at a time while keeping others constant, in the current study a more precise and effective design of experiment (DOE) approach, was used to investigate the simultaneous effect of three factors and their interactions. The study employed a central composite design (CCD) to investigate the effect of salinity, light intensity, and temperature on the toxicity, lipid, and protein production of H. akashiwo. A yeast cell assay was developed to assess toxicity, which offers rapid and convenient cytotoxicity measurements using a lower volume of samples compared to conventional methods using the whole organism. The obtained results showed that the optimum condition for toxicity of H. akashiwo was 25 °C, a salinity of 17.5, and a light intensity of 250 μmol photons m[sup.−2] s[sup.−1]. The highest amount of lipid and protein was found at 25 °C, a salinity of 30, and a light intensity of 250 μmol photons m[sup.−2] s[sup.−1]. Consequently, the combination of warm water mixing with lower salinity river input has the potential to enhance H. akashiwo toxicity, which aligns with environmental reports that establish a correlation between warm summers and extensive runoff conditions that indicate the greatest concern for aquaculture facilities.

CO[sub.2] injection to enhance shale oil recovery provides a win-win solution to meet the global fuel shortage and realize ultimate carbon neutrality. When shale reservoirs contain high salinity water, CO[sub.2] injection can result in salt precipitation to block the nanometer pores in the shale, causing undesirable formation damage. Understanding salt precipitation and dissolution dynamics at the nanoscale are fundamental to solving this practical challenge. In this work, we developed a shale micromodel to characterize salt precipitation and dissolution based on nanofluidic technology. By directly distinguishing different phases from 50 nm to 5 μm, we identified the salt precipitation sites and precipitation dynamics during the CO[sub.2] injection. For the salt precipitation in the nanometer network, we identified two precipitation stages. The ratio of the precipitation rates for the two stages is ~7.9 times that measured in microporous media, because of the slow water evaporation at the nanoscale. For the salt precipitation in the interconnected micrometer pores, we found that the CO[sub.2] displacement front serves as the salt particle accumulating site. The accumulated salt particles will in turn impede the CO[sub.2] flow. In addition, we also studied the salt dissolution process in the shale micromodel during water injection and found the classical dissolution theory overestimates the dissolution rate by approximately twofold. This work provides valuable pore-scale experimental insight into the salt precipitation and dissolution dynamics involved in shale formation, with the aim to promote the application of CO[sub.2] injection for shale oil recovery.

Several mineralized vein rocks were intruded into the granites of Rajasthan, India. In some of the vein rocks in Rajasthan has associated with enormous amount of critical metals and rare metals. The metals are spatially associated with the vein rocks of Degana, Rajasthan, India. Six samples were collected in wall and core of the vein rocks. Two samples from wall and one sample from core of each vein respectively. The samples were selected for fluid inclusion and laser Raman microprobe studies. Four distinct types of fluid inclusion were identified and classified. Type I is aqueous bi-phase ([L.sub.H2O]+[V.sub.H2O]) inclusion; Type II is aqueous-carbonic ([L.sub.H2O]+LCO2) inclusion; Type III is carbonic mono liquid (LCO2) inclusion under room temperature; Type IV is polyphase inclusion ([L.sub.H2O]+[V.sub.H2O]+S). The varying homogenization temperatures with different salinities implies mixed fluid process. The fluid process was mainly derived from the host rock granite. Later the cooled magmatic fluids were mixed with the meteoric water during hydrothermal stage may be the major key factor for formation of Li-Rb-F-W mineralization in Rajasthan, India. Keywords: Neoproterozoic; vein rock; fluid salinity; fluid boiling; carbonic inclusion; Laser Raman microprobe. Varias vetas de roca mineralizadas fueron intruidas en los granitos de Rajastan, India. Algunas de estas vetas de Rajastan presentan una enorme cantidad de metales criticos y raros. Estos metales estan asociados espacialmente con las vetas de Degana, Rajastan, India. Para este trabajo se recolectaron seis muestras de la pared y del nucleo de dos vetas. Dos muestras de la pared y una del nucleo de cada veta, respectivamente. Las muestras se seleccionaron para estudios de inclusion fluida y microsonda laser Raman. Se identificaron y clasificaron cuatro tipos distintos de inclusion fluida: el tipo I es una inclusion acuosa bifasica ([L.sub.H2O]+[V.sub.H2O]); el tipo II es una inclusion acuoso-carbonica ([L.sub.H2O] + [L.sub.CO2]); el tipo III es una inclusion carbonica monoliquida @@ a temperatura ambiente; y el tipo IV es una inclusion polifasica ([L.sub.H2O] + [V.sub.H2O] + S). La variacion en las temperaturas de homogeneizacion con diferentes salinidades implica un proceso de fluido mixto. Este proceso fluido se derivo principalmente del granito de la roca huesped. Mas tarde, los fluidos magmaticos enfriados se mezclaron con el agua meteorica durante la etapa hidrotermal, lo que puede ser el principal factor clave para la formacion de la mineralizacion de Li-Rb-F-W en Rajastan, India. Palabras clave: neoproterozoico; veta de roca; salinidad del fluido; lava; inclusion carbonica; microsonda laser Raman

Soil is an important subject as it is a fundamental component of the environment, especially considering the global information revolution and digital technologies, which have provided a realistic view for detecting soil degradation. This study relied on using spectral indices to infer soil quality in the Muqdadiya District of Diyala Governorate. It employed a range of ideas using geographical techniques (Geographic Information Systems and Remote Sensing). The study area covered 478 km², making it the second-largest district in Diyala after the governorate center.Several indices were used to assess the environmental condition of the study area, including the Bare Soil Index (BI) and the Normalized Difference Salinity Index (NDSI), over two time periods (2010-2023). The results revealed an expansion in the barren land area, which reached 160 km², accounting for 33.6% in 2010, whereas it increased to 292 km², constituting 55.4% of the total area in 2023.Regarding soil salinity, slightly saline lands covered 20 km² (3% of the total study area) in 2010. By 2023, the index showed an increase in saline lands to 221 km², or 40%, due to various human and natural factors.

How to control the frequent occurrence of cyanobacteria, especially the outbreak of toxin-producing Microcystis aeruginosa, has been a subject of constant research. This investigation focused on the effect of Moina mongolica on restricting M. aeruginosa blooms under different variables (temperature, light intensity, and salinity) and its growth at the molecular level. The results of batch experiments showed that the range of M. mongolica feeding rates was from 4.02 ± 0.81 × 10[sup.3]~182.23 ± 5.37 × 10[sup.3] cells/ind·h in the whole experiment, where the highest feeding rates of larva M. mongolica and adult M. mongolica were 133.21 ± 5.24 × 10[sup.3] vs. 182.23 ± 5.37 × 10[sup.3] cells/ind·h at 30 °C, 85.88 ± 0.44 × 10[sup.3] vs. 143.15 ± 14.07 × 10[sup.3] cells/ind·h at 3000 lx and 88.18 ± 0.32 × 10[sup.3] vs. 84.49 ± 4.95 × 10[sup.3] cells/ind·h at 0‰ salinity, respectively. The results of transcriptomics further demonstrated that the response of M. mongolica to M. aeruginosa toxicity was caused by the downregulation of relevant functional genes (cell components, cell processes, metabolic processes, and protein complexes) and related signaling pathways (apoptosis, phagosome, lysosome, ribosome, oxidative phosphorylation, amino and nucleoside sugar metabolism, and PPAR signaling pathways). The findings show that M. mongolica can be released to low-salinity lakes and coastal areas (the subtropic and temperate zones) to prevent and inhibit M. aeruginosa blooms in the early summer phase. Additionally, the results achieved by the investigation will provide the relevant technology for inhibiting cyanobacteria blooms because M. mongolica even resists the produced toxin by M. aeruginosa.

Sonneratia caseolaris is a pioneer species in mangrove. It can naturally grow in both saltwater and freshwater. The study was aimed at investigating and comparing the anatomical character of the S. caseolaris plants growing in different conditions and how they coped with salinity. The anatomical characteristics of roots, stems, petioles and leaf blade were investigated. The plant samples were prepared into permanent slides using a paraffin method, while the wood samples were made into permanent slides using a sliding microtome technique. Tissue clearing of leaf blade and scanning electron microscopic analysis of wood were performed. In addition, sodium chloride content in various organs and tissues was examined. It was found that cable root, stem and leaf blade showed some different anatomical characteristics between the two conditions. Periderm is a prominent tissue in saltwater roots. Tanniferous cells were observed in pneumatophores, petioles, stems and leaf blades of saltwater plants, but not found in pneumatophores and lamina of freshwater plants. Mesophyll thickness was lower in the saltwater condition. The vessel density was significantly higher in the saltwater condition than in the freshwater condition, whereas the vessel diameters in the freshwater condition were significantly higher than those in the saltwater condition. From the results, it can be concluded that root periderm plays an important role in salt exclusion, and the occurrence of tanniferous cells is associated with salt elimination.