Hypercrosslinked Ionic Polymers with High Ionic Content for Efficient Conversion of Carbon Dioxide into Cyclic Carbonates

The effective conversion of carbon dioxide (CO2) into cyclic carbonates requires porous materials with high ionic content and large specific surface area. Herein, we developed a new systematic post-synthetic modification strategy for synthesizing imidazolium-based hypercrosslinked ionic polymers (HIPs) with high ionic content (up to 2.1 mmol g−1) and large specific surface area (385 m2 g−1) from porous hypercrosslinked polymers (HCPs) through addition reaction and quaternization. The obtained HIPs were efficient in CO2 capture and conversion. Under the synergistic effect of high ionic content, large specific surface area, and plentiful micro/mesoporosity, the metal-free catalyst [HCP-CH2-Im][Cl]-1 exhibited quantitative selectivities, high catalytic yields, and good substrate compatibility for the conversion of CO2 into cyclic carbonates at atmospheric pressure (0.1 MPa) in a shorter reaction time in the absence of cocatalysts, solvents, and additives. High catalytic yields (styrene oxide, 120 °C, 8 h, 94% yield; 100 °C, 20 h, 93% yield) can be achieved by appropriately extending the reaction times at low temperature, and the reaction times are shorter than other porous materials under the same conditions. This work provides a new strategy for synthesizing an efficient metal-free heterogeneous catalyst with high ionic content and a large specific surface area from HCPs for the conversion of CO2 into cyclic carbonates. It also demonstrates that the ionic content and specific surface area must be coordinated to obtain high catalytic activity for CO2 cycloaddition reaction.

Regulation of salinity tolerance in Brassica juncea (L.) introgression lines: Osmoprotectants, antioxidative molecules and ionic content

Indian mustard [Brassica juncea (L.) Czern & Coss] is one of the most important oilseed crops worldwide yet drought and salinity stress significantly reduced its growth and yield. The research was carried out in order to test the effect of salinity on osmoprotectants (total soluble sugars, proline), antioxidant molecules (ascorbate, α-tocopherol) and ionic content from the dry sample of the leaves in introgression lines and varieties of Brassica juncea. Permanent saline plots are maintained in the field of soil sciences where different doses of sodium carbonate were given to maintain the relative sodium bicarbonate (RSC) to three levels. The results revealed the significant effect of salinity on biochemical attributes as well as on ionic content. Increase in total soluble sugars, proline, ascorbate, α-tocopherol and Na+ ion whereas rest of the ions Ca2+, Mg2+ and K+ decreased with increased salinity levels. Increased accumulation of Na+ increased the Na+/K+ ratio and decreased the K+/Na+. Significant finding among the introgression lines and varieties revealed low Na+ and high K+ correspondingly Na+/K+ low and K+/Na+ ratio. Decreased calcium and magnesium ion resulted in decline in chlorophyll content and membrane stability under saline conditions while decreased K+ concentration regulated the opening and closing of stomata thus hampering photosynthesis.

Numerical modeling and experimental investigation on the effect of low-salinity water flooding for enhanced oil recovery in carbonate reservoirs

Numerous studies concluded that water injection with modified ionic content/salinity in sandstones would enhance the oil recovery factor due to some mechanisms. However, the effects of smart water on carbonated formations are still indeterminate due to a lack of experimental investigations and researches. This study investigates the effects of low-salinity (Low Sal) solutions and its ionic content on interfacial tension (IFT) reduction in one of the southwestern Iranian carbonated reservoirs. A set of organized tests are designed and performed to find each ion’s effects and total dissolved solids (TDS) on the candidate carbonated reservoir. A sequence of wettability and IFT (at reservoir temperature) tests are performed to observe the effects of controlling ions (sulfate, magnesium, calcium, and sodium) and different salinities on the main mechanisms (i.e., wettability alteration and IFT reduction). All IFT tests are performed at reservoir temperature (198 °F) to minimize the difference between reservoir and laboratory-observed alterations. In this paper, the effects of four different ions (SO42-, Ca2+, Mg2+, Na+) and total salinity TDS (40,000, 20,000, 5000 ppm) are investigated. From all obtained results, the best two conditions are applied in core flooding tests to obtain the relative permeability alterations using unsteady-state methods and Cydarex software. The final part is the simulation of the whole process using the Schlumberger Eclipse black oil simulator (E100, Ver. 2010) on the candidate reservoir sector. To conclude, at Low Sal (i.e., 5000 ppm), the sulfate ion increases sulfate concentration lower IFT, while in higher salinities, increasing sulfate ion increases IFT. Also, increasing calcium concentration at high TDS (i.e., 40,000 ppm) decreases the amount of wettability alteration. In comparison, in lower TDS values (20,000 and 5000 ppm), calcium shows a positive effect, and its concentration enhanced the alteration process. Using Low Sal solutions at water cut equal or below 10% lowers recovery rate during simulations while lowering the ultimate recovery of less than 5%.

A First Step towards Determining the Ionic Content in Water with an Integrated Optofluidic Chip Based on Near-Infrared Absorption Spectroscopy

In this work, we present a feasibility study of integrated optofluidic chips to measure the ionic content in water using differential absorption spectroscopy. The second overtone of the OH-stretch vibration of water is used as indicator for both the type and concentration of the dissolved ions. The optofluidic chips are based on silicon nitride (TripleX) containing Mach–Zehnder interferometers (MZI) with two 5 cm sensing paths for the sample and reference arms, respectively. Simulations show that, theoretically, the determination of both the type and concentration of a mixture of four electrolytes is possible with the techniques presented. However, the performance of the chips deviated from the expected results due to the insufficient reproducibility and precision in the fabrication process. Therefore, at this early stage, the chips presented here could only determine the ion concentration, but not differentiate between the different ion types. Still, this work represents the first steps towards the realization of an online and real-time sensor of ionic content in water.

HYDROCHEMICAL AND SANITARY MICROBIOLOGICAL RESEARCH OF THE ELENA HILL SPRING WATERS IN THE NAKHUNAO COMMUNITY OF MARTVILI MUNICIPALITY

Hydrochemical and sanitary microbiological research of the Elena Hill spring waters in the Nakhunao community of Martvili Municipality was done for the first time.The content of Mg2+, Ca2+, Fe3+, HCO3-, Cl-, I- ions was determined. Relatively simple and quick chemical and physico-chemical methods of good repeatability were selected for determination. Biogenic substances were determined by photometric method.Carbon dioxide, oxygen BOD5 and dry remains were also identified. Sanitary-microbiological studies were performed using the following methods: mesophilic aerobes and facultative anaerobes: МУК, 2.1.4 1184-03, common coliform bacteria − МУК 4.2. 1018-01 and Escherichia coli − 18963-73. Based on the experimental data, it was found that the spring water that being researched is low-mineralized, which is why their reaction is almost neutral. The above-mentioned ionic content in the studied spring waters is within the norm, and in some samples (mesophilic aerobes and facultative anaerobes, common coliform bacteria) are established that microbiological, such a marginal concentration of pollution that is harmless for human health and its use in drinking and agricultural terms is within the norm.

Active volume regulation in adhered cells

Recent experiments reveal that the volume of adhered cells is reduced as their basal area is increased. During spreading, the cell volume decreases by several thousand cubic micrometers, corresponding to large pressure changes of the order of megapascals. We show theoretically that the volume regulation of adhered cells is determined by two concurrent conditions: mechanical equilibrium with the extracellular environment and a generalization of Donnan (electrostatic) equilibrium that accounts for active ion transport. Spreading affects the structure and hence activity of ion channels and pumps, and indirectly changes the ionic content in the cell. We predict that more ions are released from the cell with increasing basal area, resulting in the observed volume–area dependence. Our theory is based on a minimal model and describes the experimental findings in terms of measurable, mesoscale quantities. We demonstrate that two independent experiments on adhered cells of different types fall on the same master volume–area curve. Our theory also captures the measured osmotic pressure of adhered cells, which is shown to depend on the number of proteins confined to the cell, their charge, and their volume, as well as the ionic content. This result can be used to predict the osmotic pressure of cells in suspension.