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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Underground sources of drinking water chemistry changes in response to potential CO 2 leakage

The purpose of this study was to quantify changes to underground sources of drinking water (USDW) quality in response to potential CO 2 leakage from geologic CO 2 sequestration (GCS) reservoirs. Here, the developed a framework of combined laboratory experiments and reactive transport simulations and used this framework to evaluate the Ogallala aquifer overlying the Farnsworth Unit (FWU), an active GCS site, as a case study. Using chemical reaction parameters obtained from laboratory experiments and numerical simulations, site-specific mechanisms of CO 2 -water-sediment interactions at the USDW aquifer were interpreted. Long-term risks of potential CO 2 leakage were then evaluated with field-scale numerical models using the regional hydrogeological characteristics and reaction parameters obtained from our experiments and simulations. Results suggest that carbonate mineral impurity and cation exchange are key mechanisms for interactions between CO 2 and the aquifer sediment. Additionally, for a large leakage rate of 0.1 % injection from one leaky well, the leakage plume might impact an area of 300 m in diameter and significantly affect the local water quality by changing pH and cation concentrations (e.g., Zn, Ba and Sr). After leakage ceases, the zone of impacted fluids would not migrate significantly in subsequent decades due to a low regional groundwater flowrate (for this case study). The relatively small area of impact might not be detected in a monitoring well given the broader spacing in a typical field scenario. Effective early leakage detection may require additional tools, e.g., borehole CO 2 movement, four-dimensional seismicity, CO 2 soil flux, samples from deeper aquifers, etc., to ensure effective leakage detection and long-term safety of GCS projects.

58 GEOSCIENCES↗
DOE OSTI2023

Cation Disordered Anti-Perovskite Cathode Materials with Enhanced Lithium Diffusion and Suppressed Phase Transition

Recently, a new family of anti-perovskite Li 2 TMSO was discovered as promising cathode materials for Li-ion batteries (LIBs) with superiorities in high specific capacity, low cost, and environmental friendliness. However, the applications of these anti-perovskite materials meet severe challenges in the cyclability and rate performance. In this work, a cation-disordered anti-perovskite type solid solution Li 2 Fe 1– x Mn x SO (LFMSO, x = 0, 0.2, 0.5) with excellent electrochemical performance is reported. On the basis of comprehensive structural characterizations, the role of the cation disordering in LFMSO is clarified. In comparison with Li 2 FeSO (LFSO), the reduced Li-ion diffusion barrier and the increased Li-rich octahedral configurations in LFMSO with higher configurational entropy imply the facilitated long-range Li-ion diffusion and the suppressed phase transition, which favor the high-rate capability and cycling stability. In addition, the large lattice distortion and Coulombic interaction between the anions and cations lead to the breathing of the unit cell during charge/discharge. The variation of the unit cell volume decreases to 2.5% upon Li-ion delithiation. A superstructure is observed in LFMSO for the first time. These findings help to pave the way for the research and development of novel cathode materials for the next generation LIBs.

25 ENERGY STORAGE↗
DOE OSTI2026

Revealing EDL-driven reduction mechanisms in binary, ternary, and quaternary fluorinated electrolytes via an integrated MD–DFT–ML framework

Accurately predicting solid electrolyte interphase (SEI) formation requires explicitly resolving the electric double layer (EDL) structure, which deviates significantly from that of the bulk electrolyte. Although an established molecular dynamics (MD) and Density Functional Theory (DFT) framework can model SEI formation by evaluating reduction reactions of local clusters in the EDL, it suffers from a combinatorial computational bottleneck. To overcome this limitation, we introduce a machine-learning-accelerated simulation workflow (MD–DFT–ML), integrating a gradient-boosted regression model trained on EDL composition data to efficiently predict reduction potentials. We apply this framework to seven fluorinated electrolytes comprising fluorinated anions, a fluorinated ester solvent, two types of diluent (ion-solvating ester vs. non-solvating ether), and an FEC additive. The analysis shows that the EDL selectively accumulates cation-binding species; consequently, the non–cation-binding ether diluent rarely enters the EDL and makes minimal contributions to SEI formation. DFT calculations on statistically representative EDL clusters provide reduction potentials and fluorine-release pathways, while the ML model, which substantially reduces the DFT workload, predicts cluster reduction energies with a mean absolute error of 0.1 eV. The combined MD–DFT–ML approach also quantifies contributions from different sources to LiF formation in the SEI. This methodology establishes a generalizable route for multiscale modeling electrolyte and interphase design for next-generation electrochemical energy-storage systems.

DFT-MD-ML workflow↗
DOE OSTI2020

Polarizabilities of neutral atoms and atomic ions with a noble gas electron configuration

Atomic polarizabilities play an important role in the development of force fields for molecular simulations, as well as for the development of qualitative concepts of atomic and molecular behavior. Coupled cluster theory at the coupled cluster singles doubles triples level with very large correlation-consistent basis sets with extended diffuse functions has been used to predict the polarizabilities of the atomic neutrals, mono-cations and mono-anions with a noble gas configuration. Additional corrections for scalar relativistic and spin–orbit effects were also included for the electron configurations of Kr, Xe, and Rn. The results are in excellent agreement with experiment or with other high level calculations where available. The current results for most of these species represent the best available values for the polarizabilities. The results show that the polarizability of H - is very difficult to calculate without extremely diffuse functions. The polarizability of H - is the largest value, 34.05 Å 3 , calculated for all species in the current study. The polarizabilities of the remaining halogen anions are also the best available values. The polarizabilities of the halogen anions (excluding F - ) and H - have a linear correlation with the electron affinity of the neutral atom. Spin– orbit effects, even for closed shell species, cannot be ignored for quantitative accuracy, and the inclusion of spin–orbit effects for Fr + , Rn, and At - increases the polarizability by 4%, 6%, and 15%, respectively.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Cosmogenic 10 Be in pyroxene: laboratory progress, production rate systematics, and application of the 10 Be– 3 He nuclide pair in the Antarctic Dry Valleys

Here, we present cosmogenic- 10 Be and cosmogenic- 3 He data from Ferrar dolerite pyroxenes in surficial rock samples and a bedrock core from the McMurdo Dry Valleys, Antarctica, with the goal of refining the laboratory methods for extracting beryllium from pyroxene, further estimating the 10 Be production rate in pyroxene and demonstrating the applicability of 10 Be– 3 He in mafic rock. The ability to routinely measure cosmogenic 10 Be in pyroxene will open new opportunities for quantifying exposure durations and Earth surface processes in mafic rocks. We describe scalable laboratory methods for isolating beryllium from pyroxene, which include a simple hydrofluoric acid leaching procedure for removing meteoric 10 Be and the addition of a pH 8 precipitation step to reduce the cation load prior to ion exchange chromatography. 10 Be measurements in pyroxene from the surface samples have apparent 3 He exposure ages of 1–6 Myr. We estimate a spallation production rate for 10 Be in pyroxene, referenced to 3 He, of 3.6 ± 0.2 atoms g –1 yr –1 . 10 Be and 3 He measurements in the bedrock core yield initial estimates for parameters associated with 10 Be and 3 He production by negative-muon capture ($f_{10}^{*}$ = 0.00183 and $f_{3}^{*}f_{C}f_{D}$ = 0.00337). Next, we demonstrate that the 10 Be– 3 He pair in pyroxene can be used to simultaneously resolve erosion rates and exposure ages, finding that the measured cosmogenic-nuclide concentrations in our surface samples are best explained by 2–8 Myr of exposure at erosion rates of 0–35 cm Myr –1 . Finally, given the low 10 Be in our laboratory blanks (average of 5.7 × 10 3 atoms), the reported measurement precision, and our estimated production rate, it should be possible to measure 2 g samples with 10 Be concentrations of 6 × 10 4 and 1.5 × 10 4 atoms g –1 with 5 % and 15 % uncertainty, respectively. With this level of precision, Last Glacial Maximum to Late Holocene surfaces can now be dated with 10 Be in pyroxene. Application of 10 Be in pyroxene, alone or in combination with 3 He, will expand possibilities for investigating glacial histories and landscape change in mafic rock.

58 GEOSCIENCES↗
DOE OSTI2022

Ionic Dynamics of the Charge Carrier in Layered Solid Materials for Mg Rechargeable Batteries

Multivalent-ion batteries have attracted growing attention due to their high theoretical energy density that potentially outperforms Li-ion batteries. One of the critical challenges of realizing a multivalent-ion battery is the strong polarization that results in the sluggish intercalation of ions in the host lattice, which motivates a fundamental understanding of multivalent-ion dynamics in solid-state materials. In this contribution, we investigate the diffusion mechanisms of divalent ions in a novel Mg anode coating, BiOCl, using first-principles informed learning-on-the-fly molecular dynamics. Based on nanosecond-scale dynamics observations, we gained insights into the concerted diffusion mechanism of Mg cation site-to-site hopping facilitated by synchronous anion rotational motion. Furthermore, we compute the Mg-ion diffusion in additional candidate host structures screened from available layered materials space. Here, the results suggest the co-operative divalent cation-anion motion is likely a common phenomenon in layered oxyhalide structures. Our findings provide a new perspective on how to enhance multivalent-ion diffusion in layered materials.

25 ENERGY STORAGE↗
DOE OSTI2025

Polytype selection in the antisolvent-free crystallization of formamidinium lead iodide using alkylammonium chlorides

This work presents a systematic study of how the size of the C 0 –C 4 alkylammonium chloride additive directs the crystallization pathway in antisolvent-free FAPbI 3 films. We find that larger cations promote the intermediate formation of hexagonal polytypes, correlating with enhanced film crystallinity. Understanding the nucleation, crystallization, and phase transition mechanisms in perovskite thin films produced without antisolvent quenching is crucial for improving phase stability and optoelectronic performance at scale. By means of in situ grazing incidence wide-angle X-ray scattering experiments, we show that the nature of alkylammonium chloride (RACl) additives significantly influences the crystallization dynamics and temperature-dependent stability of formamidinium lead iodide (FAPbI 3 ) perovskite films formed using antisolvent-free processes. The in situ experiments reveal that the effective radius of the RA + cation and the vapor pressure of the RA 0 conjugate base are critical factors affecting the crystallization pathway and film morphology. C 2 –C 3 additives with moderate chain lengths may strike a balance between promoting the early crystallization of the cubic 3C phase while suppressing unwanted phases. This balance promotes the formation of highly crystalline cubic perovskite phase with well-oriented structure and better optoelectronic properties. These findings provide guidance regarding the design of additives to crystallize more stable and efficient perovskite films for optoelectronic applications.

Marchezi, Paulo E↗
DOE OSTI2023

Polynorbornene-based polycations

A statistical, cationic-functionalized norbornene copolymer is formed by a process including performing a vinyl addition polymerization in the presence of a metal catalyst of a first norbornene monomer substituted with a first alkyl group and at least a second norbornene monomer substituted with a second alkyl group, to form an intermediate norbornene copolymer. The second alkyl group includes a substituent which undergoes a substitution reaction with a precursor of a cationic group. The process further includes adding the precursor for the cationic group to the intermediate norbornene copolymer to form the cationic functionalized norbornene copolymer. The cationic group has a volume of 0.25 cm 3 /mol or greater (for example, a phosphonium group or an imidazolium group).

Noonan, Kevin↗
DOE OSTI2020

Understanding Cation Selectivity in Carbon Nanopores with Hybrid First-Principles/Continuum Simulations: Implications for Water Desalination and Separation Technologies

Understanding ion adsorption in porous carbons is crucial for a range of technologies, including water desalination and energy storage. In this work, we combined density functional theory with a continuum solvation model to investigate thermodynamics and kinetics of the adsorption process of alkali metal ions from aqueous solutions into carbon nanopores with different sizes and geometries. We found that cations with a larger ionic radius are more favorable to enter the nanopores because of a lower energy penalty of dehydration. In addition, the pore size and geometry were found to have a significant impact on the ion–pore interaction under confinement and cation selectivity. Our study highlights a complex interplay among nanopore geometry, ion size, and hydration on the cation adsorption selectivity, suggesting that tuning the porosity could represent a general strategy for improving ion separations.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Unraveling the Crystallization Kinetics of 2D Perovskites with Sandwich-Type Structure for High-Performance Photovoltaics

2D perovskite solar cells with high stability and high efficiency have attracted significant attention. A systematical static and dynamic structure investigation is carried out to show the details of 2D morphology evolution. A dual additive approach is used, where the synergy between an alkali metal cation and a polar solvent leads to high-quality 2D perovskite films with sandwich-type structures and vertical phase segregation. Such novel structure can induce high-quality 2D slab growth and reduce internal and surface defects, resulting in a high device efficiency of 16.48% with enhanced continuous illumination stability and improved moisture (55-60%) and thermal (85°C) tolerances. Transient absorption spectra reveal the carrier migration from low n to high n species with different kinetics. An [PbI 6 ] 4- octagon coalescence transformation mechanism coupled with metal and organic cations wrapped is proposed. By solvent vapor annealing, a recrystallization and reorientation of the 2D perovskite slabs occurs to form an ideal structure with improved device performance and stability.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Intramolecular 1,2 C-H Addition of o -Methyl Groups to Form Unique Ruthenium Pincer Tuck-in Complexes

New RPN H P ligands containing 2,4-xylyl (4mXPN H P) and mesityl (MesPN H P) groups on the phosphorus atoms were synthesized. 4mXPN H P reacts with [(cymene)RuCl 2 ] 2 followed by PMe 3 to produce κ 3 -4mXPN H PRu(PMe 3 )Cl 2 . MesPN H P reacts with [(cymene)RuCl 2 ] 2 to produce monomeric κ 3 -MesPN H PRuCl 2 that reacts with CO forming κ 3 -MesPN H PRu(CO)Cl 2 . Surprisingly, dehydrohalogenation of these complexes results in the activation of ortho methyl groups of the pincer ligands, rather than formation of κ 3 -RPNPRuLCl complexes. This results from transient κ 3 -RPNPRuLCl formation followed by 1,2-addition of an ortho C-H bond across the Ru-amide bond. The transient amide complex of κ 4 -4mXPN H PRu(PMe 3 )Cl was trapped with CO forming κ 3 -4mXPNPRu(PMe 3 )(CO)Cl. In contrast, κ 4 -MesPNHPRu(CO)Cl does not react with ligands to trap the expected amide complex of reverse C-H addition. Instead, CO and PMe 3 displace the chloride ligand forming cationic complexes. In both cases, hemi-lability of the pincer ligand was observed spectroscopically. In conclusion, the new complexes serve as precursors to moderately active catalysts for the acceptorless dehydrogenative coupling of n-butanol.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Multifaceted effects of ring fusion on the stability of charged dialkoxyarene redoxmers

Due to their almost unlimited scalability, redox flow batteries can make versatile and affordable energy storage systems. Redox active materials (redoxmers) in these batteries largely define their electrochemical performance, including the life span of the battery that depends on the stability of charged redoxmers. Here, in this study, we examine the effects of expanding the pi-system in the arene rings on the chemical stability of dialkoxyarene redoxmers that are used to store positive charge in RFBs. When 1,4-dimethoxybenzene is pi-extended to 1,4 dimethoxynaphthalene, a lower redox potential, improved kinetic stability, and longer cycling life are observed. However, when an additional ring is fused to make 9,10-dimethoxyanthracene, the radical cation undergoes rapid O -dealkylation possibly due to increased steric strain that drives methoxy out of the arene plane thus breaking the pi-conjugation with O 2p orbitals. On the other hand, the planar structure of 1,4-dimethoxynaphthalene may facilitate second -order reactions of radical cations leading to their neutralization in the bulk. Our study suggests that extending the pi-system changes reactivity in multiple (sometimes, opposite) ways, so lowering the oxidation potential through pi-conjugation to improve redoxmer stability should be pursued with caution.

25 ENERGY STORAGE↗
DOE OSTI2025

Mineral Scaling in 3D Interfacial Solar Evaporators–A Challenge for Brine Treatment and Lithium Recovery

In this work, we analyzed the effects of mineral scaling on the performance of a 3D interfacial solar evaporator, with a focus on the cations relevant to lithium recovery from brackish water. The field has been rapidly moving toward resource recovery applications from brines with higher cation concentrations. However, the potential complications caused by common minerals in these brines other than NaCl have been largely overlooked. Therefore, in this study, we thoroughly examined the effects of two common cations (calcium and magnesium) on the long-term solar evaporation performance of a 3D graphene oxide stalk. The 3D stalk can achieve an evaporation flux as high as 17.8 kg m –2 h –1 under one-sun illumination, and accumulation of NaCl on the stalk surface has no impact. However, the presence of CaCl 2 and MgCl 2 significantly reduces the evaporative flux even in solutions lacking scale-forming anions. A close examination of scale formation during long-term evaporation experiments revealed that CaCl 2 and MgCl 2 tend to precipitate out within the stalk, thus blocking water transport through the stalk and significantly dropping the evaporation rates. These findings imply that research attention is needed to modify and optimize the internal water transport channels for 3D evaporators. Additionally, we emphasize the importance of testing realistic mixtures–including prominent divalent cations– and testing long-term operations in interfacial solar evaporation research and investigating approaches to mitigate the negative impacts of divalent cations.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Mineral Scale Prevention on Electrically Conducting Membrane Distillation Membranes Using Induced Electrophoretic Mixing

The growth of mineral crystals on surfaces is a challenge across multiple industrial processes. Membrane-based desalination processes, in particular, are plagued by crystal growth (known as scaling), which restricts the flow of water through the membrane, can cause membrane wetting in membrane distillation, and can lead to the physical destruction of the membrane material. Scaling occurs when supersaturated conditions develop along the membrane surface due to the passage of water through the membrane, a process known as concentration polarization. To reduce scaling, concentration polarization is minimized by encouraging turbulent conditions and by reducing the amount of water recovered from the saline feed. In addition, antiscaling chemicals can be used to reduce the availability of cations. Here, we report on an energy-efficient electrophoretic mixing method capable of nearly eliminating CaSO4 and silicate scaling on electrically conducting membrane distillation (ECMD) membranes. The ECMD membrane material is composed of a percolating layer of carbon nanotubes deposited on porous polypropylene support and cross-linked by poly(vinyl alcohol). The application of low alternating potentials (2 Vpp,1Hz) had a dramatic impact on scale formation, with the impact highly dependent on the frequency of the applied signal, and in the case of silicate, on the pH of the solution.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

A Donor–Acceptor [2]Catenane for Visible Light Photocatalysis

Colored charge-transfer complexes can be formed by the association between electron-rich donor and electron-deficient acceptor molecules, bringing about the narrowing of HOMO–LUMO energy gaps so that they become capable of harnessing visible light. In an effort to facilitate the use of these widespread, but nonetheless weak, interactions for visible light photocatalysis, it is important to render the interactions strong and robust. Furthermore, we employ a well-known donor–acceptor [2]catenane—formed by the mechanical interlocking of cyclobis(paraquat-p-phenylene) and 1,5-dinaphtho[38]crown-10—in which the charge-transfer interactions between two 4,4'-bipyridinium and two 1,5-dioxynaphthalene units are enhanced by mechanical bonding, leading to increased absorption of visible light, even at low concentrations in solution. As a result, since this [2]catenane can generate persistent bipyridinium radical cations under continuous visible-light irradiation without the need for additional photosensitizers, it can display good catalytic activity in both photo-reductions and -oxidations, as demonstrated by hydrogen production—in the presence of platinum nanoparticles—and aerobic oxidation of organic sulfides, such as l-methionine, respectively. This research, which highlights the usefulness of nanoconfinement present in mechanically interlocked molecules for the reinforcement of weak interactions, can not only expand the potential of charge-transfer interactions in solar energy conversion and synthetic photocatalysis but also open up new possibilities for the development of active artificial molecular shuttles, switches, and machines.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Iodide manipulation using zinc additives for efficient perovskite solar minimodules

Abstract Interstitial iodides are the most critical type of defects in perovskite solar cells that limits efficiency and stability. They can be generated during solution, film, and device processing, further accelerating degradation. Herein, we find that introducing a small amount of a zinc salt- zinc trifluoromethane sulfonate (Zn(OOSCF 3 ) 2 ) in the perovskite solution can control the iodide defects in resultant perovskites ink and films. CF 3 SOO ̶ vigorously suppresses molecular iodine formation in the perovskites by reducing it to iodide. At the same time, zinc cations can precipitate excess iodide by forming a Zn-Amine complex so that the iodide interstitials in the resultant perovskite films can be suppressed. The perovskite films using these additives show improved photoluminescence quantum efficiency and reduce deep trap density, despite zinc cations reducing the perovskite grain size and iodide interstitials. The zinc additives facilitate the formation of more uniform perovskite films on large-area substrates (78-108 cm 2 ) in the blade-coating process. Fabricated minimodules show power conversion efficiencies of 19.60% and 19.21% with aperture areas of 84 and 108 cm 2 , respectively, as certified by National Renewable Energy Laboratory (NREL), the highest efficiency certified for minimodules of these sizes.

14 SOLAR ENERGY↗
DOE OSTI2022

Data from: “Significant stream chemistry response to temperature variations in a high-elevation mountain watershed”

High-elevation mountain regions, central to global freshwater supply, are experiencing more rapid warming than low-elevation locations. High-elevation streams are therefore potentially critical indicators for earth system and water chemistry response to warming. Here we present concerted hydroclimatic and biogeochemical data from Coal Creek, Colorado in the central Rocky Mountains at elevations of 2700 to 3700 m, where air temperatures have increased by about 2 °C since 1980. We analyzed water chemistry every other day from 2016 to 2019. Water chemistry data indicate distinct responses of different solutes to inter-annual hydroclimatic variations. Specifically, the concentrations of solutes from rock weathering are stable inter-annually. Solutes that are active in soils, including dissolved organic carbon, vary dramatically, with double to triple peak concentrations occurring during snowmelt and in warm years. We advocate for consistent and persistent monitoring of high elevation streams to record early glimpse of earth surface response to warming.1) Coal Creek stream were sampled and measured to answer the question if there is a significant stream chemistry response to climate change in high-elevation watershed2) The file contains data regarding discharge, water temperature and stream chemistry data for 2016-2019 year. Stream chemistry includes dissolved organic and inorganic carbon, chloride, nutrients, cations. The data collection efforts were carried out by the DOE-funded "Advancing a Watershed Hydro-Biogeochemical Theory: Linking Water Travel Time and Reaction Rates Under Changing Climate" project and Watershed Function SFA.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Substituted ALPO-5 Zeolites as Promising O 2 Sorption Pump Materials: A Density Functional Theory Study

Many chemical processes depend on having an environment that is low in oxygen partial pressure (P O2 < 100 Pa); sorption pumps are a promising route to establishing that environment by either oxygen pumping or oxygen separation from an inert gas. Near ambient sorption-based processes rely on either pressure or thermal swings, requiring no moving parts, no electricity, and neither very high nor very low temperatures. In this work, we use ab initio calculations to explore zeolites as a class of materials for sorption based oxygen pumping/separation. Our calculations indicate that while the neat ALPO-5 zeolite does not adsorb O 2 , O 2 does adsorb on zeolites selectively substituted with transition metals and metalloids and hence, can enable separation and pumping. ALPO-5 substituted with Si, Ge, Sn, Pd, Pt, Ti, V, Cr, Mn, Zr, Mo, Hf, W, Ce, and Pr provides adsorption energies ranging from -0.19 to -3.92 eV, (-) indicates exothermic process. Additionally, we provide a comprehensive understanding of what controls the adsorption energy: 1) the substi-tutions must be able to adopt an oxidation state that is more positive than the cation it replaces, and 2) the size of the pore into which the O 2 adsorbs to the wall. Additionally, we conduct a ther-modynamic analysis of a thermal swing cycle to approximate the optimal O 2 binding energy for 2 low energy O 2 pumping/separation. We find that the minimum energy cost likely occurs when the adsorption energy is in the range of 0.75 – 1.00 eV (72 – 97 kJ·mol -1 ), which corresponds to Ge, V, Pt, or Ce substituted ALPO-5.

36 MATERIALS SCIENCE↗