Domain: Engineering — Civil & Environmental Engineering
Target concept: Filtration of dye-contaminated water using activated carbon in a transparent column

Video generation prompt: A transparent vertical cylindrical column is filled with activated carbon; the dye-contaminated water flows from the top to the bottom and finally exits from the bottom into a transparent container.

Evaluation guide:
(i) Target concept: Adsorptive filtration of soluble dye by stationary activated carbon in a gravity-fed transparent column.
Minimum mechanism: Dye must be molecularly dissolved (not particulate), carbon must be porous and inert, flow must be laminar enough to allow contact time, and adsorption must dominate over mechanical straining alone.
(ii)Storyline: [Frame 0–2] Transparent cylindrical column fully visible, upright, filled with dry granular activated carbon; [Frame 2–4] Colored aqueous dye solution poured steadily onto top surface: no splashing, no overflow; [Frame 4–7] Colored liquid visibly descends through carbon bed, maintaining column confinement; [Frame 7–9] Clear/lightened effluent emerges from bottom outlet and enters transparent container below; [Frame 9–10] Effluent stream remains continuous, centered, and stable: no interruption, no color resurgence. Perspective: Fixed frontal/slightly angled side view showing full column height, top inlet, carbon bed, bottom outlet, and container in single unbroken shot; all critical interfaces (inlet surface, carbon–liquid boundary, outlet orifice, container meniscus) must remain simultaneously visible and unoccluded.

Manual:
Experimental Procedure
1. Place a transparent vertical cylindrical column upright.
2. Fill column with granular activated carbon.
3. Pour dye-contaminated water (e.g., blue food dye solution) slowly into the top opening.
4. Observe water percolating downward through carbon bed.
5. Collect effluent in a transparent container placed directly beneath column outlet.
Observation of Experimental Phenomena
- Influent is uniformly colored (e.g., vivid blue).
- Effluent exiting bottom is visibly lighter in color saturation; ideally near-colorless.
- Activated carbon stays in place, keeping its granular form and dark color with no visible change in appearance.
- Flow is continuous from top inlet to bottom outlet without leakage or bypass.
Summary of Experimental Principles
Activated carbon removes dye via adsorption: dye molecules bind to the high-surface-area pores of the carbon, pulling color out of the solution without producing any visible change to the carbon's own appearance. Filtration occurs under gravity-driven flow through a fixed carbon bed.

Prompt Grounding rubric:
level_1: No transparent vertical cylindrical column appears at all, or activated carbon is nowhere visible inside a container; dye-contaminated water is never introduced, or no downward top-to-bottom flow is shown; no separate transparent container receives any effluent.
level_2: A vertical cylindrical column is present, but it is not transparent or is not filled with activated carbon; colored dye-contaminated water appears somewhere in the scene but not entering at the top of the column; the effluent container is missing or opaque; the direction of flow is unclear or wrong, e.g., sideways, upward, or the liquid never visibly moves.
level_3: A transparent vertical cylindrical column is visible and clearly contains granular material; colored water is introduced at the column's top opening; the liquid moves downward through the column; a transparent container sits directly beneath the column's outlet and catches the exiting liquid; the column, carbon, colored water, and container are all present and arranged as described in a single continuous view.
level_4: The column stays upright and in the same position for the whole video; the granular carbon bed stays in place inside the column without floating, clumping into a single mass, or shifting position; water enters only through the top opening and exits only through the bottom outlet, with no leaks elsewhere on the column; nothing not implied by the setup, such as a funnel, extra tubing, or a hand, blocks the view of the column or container.
level_5: The column has a clearly circular cross-section typical of a cylinder viewed from the side, is fully see-through with no tint, and stands perfectly vertical; the granular carbon fills the column evenly from about two-thirds of its height up to the very top; the colored water enters only at the flat top surface of the carbon bed, not through a side port or from below; the effluent exits only from a central bottom outlet and lands inside the container without splashing outside it; the column, carbon, liquid, and container remain clearly identifiable and correctly positioned throughout, with no visual glitch obscuring any of them.

Scientific and Causal Correctness rubric:
level_1: No decolorization occurs at all: the effluent exiting the bottom is the same hue and intensity as the influent entering the top, indicating no adsorption is taking place; the carbon shows no visible response to the dye whatsoever, or is entirely absent from the flow path.
level_2: A color change occurs but violates the adsorption mechanism: e.g., the effluent becomes a new or more intense color than the influent, the carbon bed bubbles, fizzes, or visibly dissolves as if reacting chemically with the dye, or dye color that had cleared reappears in the effluent later with no plausible cause; these effects are inconsistent with simple physical adsorption onto a stationary carbon bed.
level_3: The effluent leaving the bottom is visibly lighter in color than the dye-laden influent entering the top, consistent with dye being captured somewhere in the column; the carbon bed shows no evidence of chemical reaction, such as bubbling, fizzing, dissolving, or disintegrating; any darkening visible on the carbon stays confined to the carbon itself and does not leach back into the liquid or discolor the column wall.
level_4: The effluent is substantially lighter than the influent, noticeably paler in saturation, and this lightening holds steady for the full duration of outflow without darkening rebounding partway through; the carbon bed keeps a uniform granular texture and its original dark color, with no visible erosion, leaching, or discoloration.
level_5: The effluent reaches a distinctly pale or near-clear state relative to the strongly colored influent, and this clarity is maintained continuously through the entire outflow with no rebound; the carbon grains remain sharply defined, non-agglomerated, and keep their original dark color, with no surface staining or leached pigment visible on the carbon or the column wall; no carbon disintegration, gas evolution, or dye leaching onto the column walls or into the container occurs at any point.

Spatiotemporal Consistency rubric:
level_1: Severe breaks in continuity: the column disappears and reappears, or jumps to a different position between frames; the carbon bed vanishes or reappears without the liquid ever visibly passing through it; colored liquid appears instantly at the bottom outlet without ever being seen descending through the column; the effluent container jumps to a new position or orientation; the overall scene lighting switches on and off or otherwise changes abruptly with no visible cause; the column itself visibly bends, cracks, or collapses.
level_2: Noticeable but less severe breaks: the column wobbles, tilts, or rotates in a way inconsistent with a fixed, upright setup; the carbon bed shifts downward as a solid mass rather than staying in place while liquid percolates through it; colored liquid appears at the bottom well before any visible front has traveled down through the carbon; the effluent container enters the shot late or leaves before the video ends; the direction of the column's shadow changes partway through the video without a corresponding change in the light source; the flow visibly freezes for a stretch and then jumps forward.
level_3: The column, carbon bed, and effluent container each stay in one fixed location and orientation for the whole video; the colored liquid enters at the top and is seen moving continuously downward before reaching the outlet, rather than skipping the transit; overall scene lighting stays even across the video, without one part of the frame darkening or brightening independently of the rest; no part of the column, carbon, or container is ever clipped, distorted, or occluded in a way that breaks the sense that all four elements belong to one continuous, physically coherent scene.
level_4: The descent of the liquid through the carbon looks physically natural: a steady downward front rather than liquid floating, speeding up and slowing down erratically, or behaving like a much thicker or thinner fluid than water; the carbon grains themselves do not visibly jump or resettle as liquid moves past them; the column's transparent wall shows a plausible, steady amount of light bending through it rather than distorting differently from one moment to the next; the liquid level rising in the container below increases steadily without ever dropping or jumping to a new level.
level_5: Motion is smooth throughout with no stutter, freeze-frame, or sudden jump that breaks the sense of continuous flow; the descending liquid's visible surface stays coherent rather than flickering in and out; the column does not appear to shift relative to the background in a way that would suggest camera movement; the shadow the column casts keeps the same shape and points the same way for the whole video, matching a single light source that never moves; the column's transparency and the carbon's granular texture look like the same material from one frame to the next, without flicker or warping that would suggest an unstable image.