| Initial letter | Keywords | Count |
|---|
| 0-9 | 3D printing (3), 5-hydroxymethylfurfural (3), 2,2'-bipyridine (1), 2'-Octoxyacetophenone (1), 3DIC (1), 3D imaging (1), etc. | 10 |  |
|---|
| A | Adsorption (11), ammonia (7), antibody (3), Agglomeration (3), atomic layer deposition (3), aqueous two-phase system (3), etc. | 157 | |
|---|
| B | biomass (5), Biochar (3), Biomass gasification (3), bio-oil (3), Biomethanation (3), biopharmaceuticals (2), etc. | 89 | |
|---|
| C-CH | CFD (8), Carbon nanotube (8), Catalyst (6), Carbon Neutral (6), CCS (5), Carbon dioxide (5), etc. | 157 | |
|---|
| CI-CZ | CO2 capture (12), Crystallization (8), CO2 (7), Computational fluid dynamics (6), COSMO-SAC (5), CO2 methanation (4), etc. | 171 | |
|---|
| D | Deep learning (6), deep eutectic solvent (6), Deep Tech (5), Dehydration (4), Drying (4), Direct air capture (4), etc. | 128 | |
|---|
| E | Electrocatalysts (5), Escherichia coli (5), electrolysis (4), extraction (4), electrocatalyst (3), Economic Evaluation (3), etc. | 108 | |
|---|
| F | Fast Pyrolysis Bio-Oil (2), Fischer-Tropsch synthesis (2), Flue gas (2), Fischer-Tropsch (2), Fluid Mechanics (2), Flame spray pyrolysis (2), etc. | 69 | |
|---|
| G | Graphene (3), Green Hydrogen (2), Green transformation (2), Gamma-butyrolactone (GBL) (1), Grain boundaries (1), Gas holdup (1), etc. | 53 | |
|---|
| H | Hydrogen Production (15), Hydrogen (11), hydrogel (7), Hydrogen storage (5), Hydrate (2), Heat and mass transfer (2), etc. | 128 | |
|---|
| I | interfacial polymerization (2), I-V characteristics (2), interfacial affinity (2), ion gel (2), Impedance (1), ionic gel (1), etc. | 63 | |
|---|
| K | Knowledge Management (1), Key group (1), kolbe electrolysis (1), kernel method (1), key parameters (1), kinetic study (1), etc. | 8 | |
|---|
| L | lithium-ion battery (3), liquid-liquid mixing (3), liposome (3), lithium-Ion batteries (3), Lithium-ion Battery Recycling (2), Life cycle assessment (2), etc. | 78 | |
|---|
| M-MH | Machine Learning (36), membrane (12), Metal-Organic Frameworks (11), Metabolic Engineering (9), Mechanochemistry (5), Methane Fermentation (4), etc. | 154 | |
|---|
| MI-MZ | Molecular dynamics (12), Mixing (11), Molecular dynamics simulation (5), Microfluidic device (3), Microalgae (3), Multi-objective optimization (2), etc. | 107 | |
|---|
| N | Numerical Simulation (12), nanoparticles (4), nanoparticle (4), neural network (3), Nanofiltration (2), Ni catalyst (2), etc. | 89 | |
|---|
| Non alphanumeric | * (17) | 17 | |
|---|
| O | optimization (4), organic chelating ligand (2), Operations and Maintenance (2), Ozonation (1), Organizational Accident (1), organic ligand (1), etc. | 43 | |
|---|
| P-PH | PFAS (6), pervaporation (3), Photocatalyst (3), Phase Change Material (2), particle size (2), phase equilibrium (2), etc. | 81 | |
|---|
| PI-PZ | Process Simulation (9), polymer (5), process modeling (5), process design (3), Process informatics (2), Plot Plan (2), etc. | 139 | |
|---|
| Q | quantitative visualization (1), Qualification system (1), Quantum computing (1), Questionnaire Survey (1), Quadrupole Mass Spectrometry (1) | 5 | |
|---|
| R | recycling (4), Redox flow battery (4), Renewable energy (4), Rotating bed (3), Regenerative medicine (3), Recycle (3), etc. | 84 | |
|---|
| S-SO | Simulation (4), slug flow (4), Seawater Electrolysis (4), Softsensor (3), SOEC (3), SiC (2), etc. | 112 | |
|---|
| SP-SZ | Startup (5), Supercritical Fluid Deposition (5), Surfactant (4), Suspension (3), Spray drying (3), Surrogate model (2), etc. | 94 | |
|---|
| T | Transfer learning (2), thermal management (2), tandem catalyst (1), techno-economics (1), Transitional flow regime (1), Techno-economic assessment (1), etc. | 58 | |
|---|
| U | Ultrasound (3), Umbrella sampling (1), Ultrasonic velocity (1), UVGI (1), Ultrafine bubbles (1), ultrafiltration (1), etc. | 15 | |
|---|
| V | Viscosity (5), vesicle (3), Viscoelastic Fluid (2), vapor-liquid equilibrium (1), Viscoelasticity (1), Volume of Fluid Method (1), etc. | 27 | |
|---|
| W | Water Electrolysis (10), Water treatment (7), woody biomass (3), Waste utilization (2), wetting (1), Wind turbine (1), etc. | 45 | |
|---|
| X | X-Ray CT (1) | 1 | |
|---|
| Y | Yield stress (1), Yarrowia lipolytica (1), yielding behavior (1), Yttrium doping (1) | 4 | |
|---|
| Z | zeolite (12), ZIF-8 (2), Zero-shot regression (1), Zinc-Air Battery (1), ZnO formation (1), Zinc Oxide (1), etc. | 21 | |
|---|
