उचित चाकू पंजीकरण (proper knife registration) के लिए निम्नलिखित... | Agrigyan

In mechanical threshing engineering:
Decreased concave clearance (A): Narrowing the gap between the cylinder rasp bars/pegs and the concave grates subjects grain to severe pinching, impact, and shearing forces, drastically increasing grain breakage/cracking.
Increased feed rate (D): Overfeeding causes choking, high inter-particle friction, and severe mechanical impact inside the threshing drum, escalating mechanical seed damage.
Official NTA key explicitly designates (A) and (D) only (Option 3).
(Note: Very low seed moisture (B) also renders seeds brittle, but in the context of operating machine adjustments, concave clearance and feed rate are primary operational drivers).

The Reid Vapour Pressure (RVP) test (ASTM D323) measures the absolute vapor pressure exerted by volatile liquid fuels (particularly gasoline and aviation fuel) at 37.8°C (100°F) with a vapor-to-liquid ratio of 4:1:
It is the standard industrial test used to evaluate fuel volatility, which governs cold engine starting, warm-up behavior, and susceptibility to vapor lock in fuel supply lines.

Fuel combustion requirements for CI and SI internal combustion engines:
1. Compression Ignition (CI / Diesel) Engine: Fuel is injected into hot compressed air and must ignite spontaneously with minimal ignition delay. Therefore, a good CI fuel requires a low self-ignition temperature (high Cetane number) to promote easy autoignition \(\rightarrow\) \lt strong\gt (C)\lt /strong\gt . 2. \lt strong\gt Spark Ignition (SI / Petrol) Engine\lt /strong\gt : The air-fuel mixture is compressed together; it must NOT auto-ignite spontaneously before the timed spark occurs, or violent knocking/detonation results. Therefore, a good SI fuel requires a \lt strong\gt high self-ignition temperature\lt /strong\gt (high Octane number) to resist premature autoignition \(\rightarrow\) (D).