{"query": "Nitrogen (N) — element 7", "count": 20, "results": [{"id": "card_ref_el_007", "title": "Nitrogen (N) — element 7", "shelf": "chemistry", "surface": "secular", "snippet": "Atomic number 7. Symbol N. Standard atomic weight 14.007. The nitrogen atom carries 7 protons in its nucleus; its place in the periodic table is fixed by that count. Verified reference data.", "authority_tier": "reference", "source": "Verified reference — chemistry", "readable": false, "generated": false}, {"id": "card_theory_haber_bosch", "title": "Haber–Bosch nitrogen fixation (bread from air)", "shelf": "theories", "surface": "secular", "snippet": "Haber–Bosch nitrogen fixation (bread from air) — an engine domain that can touch it: chemistry. Calibration: seals — stoichiometry, yield and equilibrium shifts compute. N₂ + 3H₂ ⇌ 2NH₃, run at roughl", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_biological_nitrogen_fixation", "title": "Crop rotation & biological nitrogen fixation (the low-input path)", "shelf": "theories", "surface": "secular", "snippet": "Crop rotation & biological nitrogen fixation (the low-input path) — an engine domain that can touch it: agriculture. Calibration: map-only — rotation effects are empirical; nutrient budgets compute. L", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_law_of_the_minimum", "title": "Liebig's law of the minimum (what actually limits growth)", "shelf": "theories", "surface": "secular", "snippet": "Liebig's law of the minimum (what actually limits growth) — an engine domain that can touch it: soil_science. Calibration: seals — nutrient ratios and deficiency thresholds compute. Growth is limited ", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_stellar_nucleosynthesis_the_hr_diagram", "title": "Stellar nucleosynthesis & the HR diagram", "shelf": "theories", "surface": "secular", "snippet": "Stellar nucleosynthesis & the HR diagram — an engine domain that can touch it: astronomy. Calibration: partial — specific relations verify; the theory as a whole is not a sealable computation. Where t", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_nutrient_cycling_agronomy", "title": "Nutrient cycling & agronomy (NPK, evapotranspiration)", "shelf": "theories", "surface": "secular", "snippet": "Nutrient cycling & agronomy (NPK, evapotranspiration) — an engine domain that can touch it: soil_science. Calibration: seals — nutrient budgets and ET rates compute. Elements cycle between soil, plant", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_green_revolution", "title": "The Green Revolution (Borlaug, semi-dwarf breeding)", "shelf": "theories", "surface": "secular", "snippet": "The Green Revolution (Borlaug, semi-dwarf breeding) — an engine domain that can touch it: agriculture. Calibration: map-only — yields are historical measurements, not a sealable computation. Norman Bo", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_agricultural_science", "title": "Agricultural science (yield, soil-pH suitability)", "shelf": "theories", "surface": "secular", "snippet": "Agricultural science (yield, soil-pH suitability) — an engine domain that can touch it: agriculture. Calibration: seals — yield, spacing, seeding rates and pH suitability compute. Yield is the product", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_theory_biochemistry_enzymes", "title": "Biochemistry & enzymes (catalysis at body temperature)", "shelf": "theories", "surface": "secular", "snippet": "Biochemistry & enzymes (catalysis at body temperature) — an engine domain that can touch it: biology. Calibration: seals — reaction rates, Michaelis–Menten kinetics and energy budgets compute. An enzy", "authority_tier": "reference", "source": "The Theory Assay — calibrated, not judged (docs/THEORY_CATALOG.md)", "readable": false, "generated": false}, {"id": "card_src_openstax_anatomy_and_physiology_2e_chapter_review_6112a6f1", "title": "Chapter Review — Anatomy and Physiology 2e", "shelf": "medicine", "surface": "secular", "snippet": "Chapter Review\n\n2.1\n\nElements and Atoms: The Building Blocks of Matter\n\nThe human body is composed of elements, the most abundant of which are oxygen (O), carbon (C), hydrogen (H) and nitrogen (N). Yo", "authority_tier": "reference", "source": "OpenStax: Anatomy and Physiology 2e (CC-BY 4.0)", "readable": false, "generated": false}, {"id": "card_src_openstax_anatomy_and_physiology_chapter_review_3e151ada", "title": "Chapter Review — Anatomy and Physiology", "shelf": "medicine", "surface": "secular", "snippet": "Chapter Review\n\n2.1\n\nElements and Atoms: The Building Blocks of Matter\n\nThe human body is composed of elements, the most abundant of which are oxygen (O), carbon (C), hydrogen (H) and nitrogen (N). Yo", "authority_tier": "reference", "source": "OpenStax: Anatomy and Physiology (CC-BY 4.0)", "readable": false, "generated": false}, {"id": "card_src_openstax_anatomy_and_physiology_2e_review_questions_95f64ff2", "title": "Review Questions — Anatomy and Physiology 2e", "shelf": "medicine", "surface": "secular", "snippet": "Review Questions\n\n4.\n\nTogether, just four elements make up more than 95 percent of the body’s mass. These include ________.\n\ncalcium, magnesium, iron, and carbon\n\noxygen, calcium, iron, and nitrogen\n\n", "authority_tier": "reference", "source": "OpenStax: Anatomy and Physiology 2e (CC-BY 4.0)", "readable": false, "generated": false}, {"id": "card_src_openstax_anatomy_and_physiology_review_questions_b373a7e0", "title": "Review Questions — Anatomy and Physiology", "shelf": "medicine", "surface": "secular", "snippet": "Review Questions\n\n4.\n\nTogether, just four elements make up more than 95 percent of the body’s mass. These include ________.\n\ncalcium, magnesium, iron, and carbon\n\noxygen, calcium, iron, and nitrogen\n\n", "authority_tier": "reference", "source": "OpenStax: Anatomy and Physiology (CC-BY 4.0)", "readable": false, "generated": false}, {"id": "card_food_companion_rotation", "title": "Companion planting and crop rotation", "shelf": "agriculture", "surface": "secular", "snippet": "Don't grow the same crop in the same spot year after year — ROTATE by plant family so pests and diseases can't build up and so heavy feeders (corn, brassicas) follow soil-builders (beans, peas, which ", "authority_tier": "reference", "source": "USDA Farmers' Bulletins & extension guidance (U.S. government, public domain)", "readable": false, "generated": false}, {"id": "card_floor_agriculture", "title": "Agriculture — soil, sun, and chemistry into food", "shelf": "codex", "surface": "secular", "snippet": "Crops fix carbon by photosynthesis (glucose) and need fixed nitrogen (Haber-Bosch ammonia, feeding half the world). Pillars rest on biology (the crop), chemistry (fertilizer and photosynthesis) and ec", "authority_tier": "engine_derived", "source": "Narrow Highway — agriculture", "readable": false, "generated": false}, {"id": "card_food_soil", "title": "Feed the soil, not just the plant", "shelf": "agriculture", "surface": "secular", "snippet": "Healthy soil grows healthy food; poor soil grows failure. Build it with ORGANIC MATTER — compost, aged manure, leaf mold, cover crops turned in — which feeds soil life, holds water, and releases nutri", "authority_tier": "reference", "source": "USDA Farmers' Bulletins & extension guidance (U.S. government, public domain)", "readable": false, "generated": false}, {"id": "card_agriculture_fertilizer", "title": "Fertilizer - fixing nitrogen", "shelf": "codex", "surface": "secular", "snippet": "Haber-Bosch makes ammonia (sealed), the synthetic nitrogen that feeds roughly half the world. Rests on chemistry.", "authority_tier": "engine_derived", "source": "Narrow Highway — agriculture", "readable": false, "generated": false}, {"id": "card_src_openstax_biology_2e_chapter_summary_42cb1097", "title": "Chapter Summary — Biology 2e", "shelf": "biology", "surface": "secular", "snippet": "Chapter Summary\n\n31.1\n\nNutritional Requirements of Plants\n\nPlants can absorb inorganic nutrients and water through their root system, and carbon dioxide from the environment. The combination of organi", "authority_tier": "reference", "source": "OpenStax: Biology 2e (CC-BY 4.0)", "readable": false, "generated": false}, {"id": "card_floor_soil_science", "title": "Soil science — the living skin of the land", "shelf": "codex", "surface": "secular", "snippet": "Soil is mineral, water, air and organic matter in rough proportion, alive with microbes, holding nutrients by a carbon-to-nitrogen balance. Pillars rest on chemistry (minerals and nutrients), earth sc", "authority_tier": "engine_derived", "source": "Narrow Highway — soil", "readable": false, "generated": false}, {"id": "card_src_openstax_biology_chapter_summary_c7213441", "title": "Chapter Summary — Biology", "shelf": "biology", "surface": "secular", "snippet": "Chapter Summary\n\n31.1\n\nNutritional Requirements of Plants\n\nPlants can absorb inorganic nutrients and water through their root system, and carbon dioxide from the environment. The combination of organi", "authority_tier": "reference", "source": "OpenStax: Biology (CC-BY 4.0)", "readable": false, "generated": false}], "house": {"door": "FIND", "kind": "cards", "trail": "results", "seal": null, "next_step": {"do": "open the top card", "door": "FIND", "tool": "card_get", "params": {"id": "card_ref_el_007"}}, "ends": "a verdict or a card · the trail · a seal · one next step"}}