Input:
Polycrystalline Cu 2-δ Fe x S (δ = 0.1, x = 0, 0.0125, 0.0225, and 0.0325) and Cu 2-δ S (δ = 0, 0.01, 0.03, 0.04, 0.06, and 0.1) samples were synthesized by a combination of melting and long-term high-temperature annealing method. High purity raw elements, Cu (shot, 99.999%, Alfa Aesar), S (shot, 99.999%, Alfa Aesar), and Fe (shots, 99.98%, Alfa Aesar) were weighed in their stoichiometric ratios and placed in boron nitride crucibles, and then sealed in fused silica tubes under vacuum. The temperature of the tubes was slowly raised to 1423 K in 6 h and then maintained at this temperature for 12 h before quenching into ice water. Then, the ingots were annealed at 773 K for 5 d. The annealed ingots were crushed into powders and consolidated by spark plasma sintering (Sumitomo SPS-2040) at 723 K under a pressure of 65 MPa for 5 min. Electrically insulating but thermally conducting BN layers were sprayed onto the carbon foils and the inner sides of the graphite die before the SPS process in order to prohibit DC pulsed currents going through the powders.

Output:
[
  {
    "label": "Cu2−δS_composition variation",
    "@graph": [
      {
        "@type": "Entity",
        "@id": "e1",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "Cu" }],
        "matprov:purity": [{ "@value": "99.999 %" }],
        "matprov:form": [{ "@value": "shot" }]
      },
      {
        "@type": "Entity",
        "@id": "e2",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "S" }],
        "matprov:purity": [{ "@value": "99.999 %" }],
        "matprov:form": [{ "@value": "shot" }]
      },
      {
        "@type": "Entity",
        "@id": "e12",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "fused silica tube" }]
      },
      {
        "@type": "Entity",
        "@id": "e13",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "boron nitride crucible" }]
      },
      {
        "@type": "Activity",
        "@id": "a3",
        "label": [{ "@value": "sealing" }],
        "matprov:atmosphere": [{ "@value": "vacuum" }]
      },
      { "@type": "Usage", "activity": "a3", "entity": "e1" },
      { "@type": "Usage", "activity": "a3", "entity": "e2" },
      { "@type": "Usage", "activity": "a3", "entity": "e13" },
      { "@type": "Usage", "activity": "a3", "entity": "e12" },
      { "@type": "Generation", "activity": "a3", "entity": "e5" },
      {
        "@type": "Entity",
        "@id": "e5",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "sealed sample" }]
      },
      {
        "@type": "Activity",
        "@id": "a4",
        "label": [{ "@value": "raising" }],
        "matprov:temperature": [{ "@value": "1423 K" }],
        "matprov:duration": [{ "@value": "6 h" }]
      },
      { "@type": "Usage", "activity": "a4", "entity": "e5" },
      { "@type": "Generation", "activity": "a4", "entity": "e6" },
      {
        "@type": "Entity",
        "@id": "e6",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "raised sample" }]
      },
      {
        "@type": "Activity",
        "@id": "a5",
        "label": [{ "@value": "maintaining" }],
        "matprov:temperature": [{ "@value": "1423 K" }],
        "matprov:duration": [{ "@value": "12 h" }]
      },
      { "@type": "Usage", "activity": "a5", "entity": "e6" },
      { "@type": "Generation", "activity": "a5", "entity": "e7" },
      {
        "@type": "Entity",
        "@id": "e7",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "maintained sample" }]
      },
      {
        "@type": "Activity",
        "@id": "a6",
        "label": [{ "@value": "quenching" }]
      },
      { "@type": "Usage", "activity": "a6", "entity": "e7" },
      {
        "@type": "Entity",
        "@id": "e16",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "ice water" }]
      },
      { "@type": "Usage", "activity": "a6", "entity": "e16" },
      { "@type": "Generation", "activity": "a6", "entity": "e8" },
      {
        "@type": "Entity",
        "@id": "e8",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "quenched sample" }],
        "matprov:form": [{ "@value": "ingot" }]
      },
      {
        "@type": "Activity",
        "@id": "a7",
        "label": [{ "@value": "annealing" }],
        "matprov:temperature": [{ "@value": "773 K" }],
        "matprov:duration": [{ "@value": "5 d" }]
      },
      { "@type": "Usage", "activity": "a7", "entity": "e8" },
      { "@type": "Generation", "activity": "a7", "entity": "e9" },
      {
        "@type": "Entity",
        "@id": "e9",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "annealed sample" }],
        "matprov:form": [{ "@value": "ingot" }]
      },
      {
        "@type": "Activity",
        "@id": "a8",
        "label": [{ "@value": "crushing" }]
      },
      { "@type": "Usage", "activity": "a8", "entity": "e9" },
      { "@type": "Generation", "activity": "a8", "entity": "e10" },
      {
        "@type": "Entity",
        "@id": "e10",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "crushed sample" }],
        "matprov:form": [{ "@value": "powder" }]
      },
      {
        "@type": "Activity",
        "@id": "a9",
        "label": [{ "@value": "spark plasma sintering" }],
        "matprov:temperature": [{ "@value": "723 K" }],
        "matprov:pressure": [{ "@value": "65 MPa" }],
        "matprov:duration": [{ "@value": "5 min" }]
      },
      { "@type": "Usage", "activity": "a9", "entity": "e10" },
      {
        "@type": "Entity",
        "@id": "e14",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "SPS-2040" }]
      },
      { "@type": "Usage", "activity": "a9", "entity": "e14" },
      { "@type": "Generation", "activity": "a9", "entity": "e11" },
      {
        "@type": "Entity",
        "@id": "e11",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "spark plasma sintered sample" }]
      }
    ]
  },
  {
    "label": "Cu2−δFexS_composition variation",
    "@graph": [
      {
        "@type": "Entity",
        "@id": "e1",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "Cu" }],
        "matprov:purity": [{ "@value": "99.999 %" }],
        "matprov:form": [{ "@value": "shot" }]
      },
      {
        "@type": "Entity",
        "@id": "e2",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "S" }],
        "matprov:purity": [{ "@value": "99.999 %" }],
        "matprov:form": [{ "@value": "shot" }]
      },
      {
        "@type": "Entity",
        "@id": "e3",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "Fe" }],
        "matprov:purity": [{ "@value": "99.98 %" }],
        "matprov:form": [{ "@value": "shot" }]
      },
      {
        "@type": "Entity",
        "@id": "e13",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "fused silica tube" }]
      },
      {
        "@type": "Entity",
        "@id": "e14",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "boron nitride crucible" }]
      },
      {
        "@type": "Entity",
        "@id": "e15",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "SPS-2040" }]
      },
      {
        "@type": "Activity",
        "@id": "a3",
        "label": [{ "@value": "sealing" }],
        "matprov:atmosphere": [{ "@value": "vacuum" }]
      },
      { "@type": "Usage", "activity": "a3", "entity": "e1" },
      { "@type": "Usage", "activity": "a3", "entity": "e2" },
      { "@type": "Usage", "activity": "a3", "entity": "e3" },
      { "@type": "Usage", "activity": "a3", "entity": "e14" },
      { "@type": "Usage", "activity": "a3", "entity": "e13" },
      { "@type": "Generation", "activity": "a3", "entity": "e6" },
      {
        "@type": "Entity",
        "@id": "e6",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "sealed sample" }]
      },
      {
        "@type": "Activity",
        "@id": "a4",
        "label": [{ "@value": "raising" }],
        "matprov:temperature": [{ "@value": "1423 K" }],
        "matprov:duration": [{ "@value": "6 h" }]
      },
      { "@type": "Usage", "activity": "a4", "entity": "e6" },
      { "@type": "Generation", "activity": "a4", "entity": "e7" },
      {
        "@type": "Entity",
        "@id": "e7",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "raised sample" }]
      },
      {
        "@type": "Activity",
        "@id": "a5",
        "label": [{ "@value": "maintaining" }],
        "matprov:temperature": [{ "@value": "1423 K" }],
        "matprov:duration": [{ "@value": "12 h" }]
      },
      { "@type": "Usage", "activity": "a5", "entity": "e7" },
      { "@type": "Generation", "activity": "a5", "entity": "e8" },
      {
        "@type": "Entity",
        "@id": "e8",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "maintained sample" }]
      },
      {
        "@type": "Activity",
        "@id": "a6",
        "label": [{ "@value": "quenching" }]
      },
      { "@type": "Usage", "activity": "a6", "entity": "e8" },
      {
        "@type": "Entity",
        "@id": "e16",
        "type": [{ "@value": "tool" }],
        "label": [{ "@value": "ice water" }]
      },
      { "@type": "Usage", "activity": "a6", "entity": "e16" },
      { "@type": "Generation", "activity": "a6", "entity": "e9" },
      {
        "@type": "Entity",
        "@id": "e9",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "quenched sample" }],
        "matprov:form": [{ "@value": "ingot" }]
      },
      {
        "@type": "Activity",
        "@id": "a7",
        "label": [{ "@value": "annealing" }],
        "matprov:temperature": [{ "@value": "773 K" }],
        "matprov:duration": [{ "@value": "5 d" }]
      },
      { "@type": "Usage", "activity": "a7", "entity": "e9" },
      { "@type": "Generation", "activity": "a7", "entity": "e10" },
      {
        "@type": "Entity",
        "@id": "e10",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "annealed sample" }],
        "matprov:form": [{ "@value": "ingot" }]
      },
      {
        "@type": "Activity",
        "@id": "a8",
        "label": [{ "@value": "crushing" }]
      },
      { "@type": "Usage", "activity": "a8", "entity": "e10" },
      { "@type": "Generation", "activity": "a8", "entity": "e11" },
      {
        "@type": "Entity",
        "@id": "e11",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "crushed sample" }],
        "matprov:form": [{ "@value": "powder" }]
      },
      {
        "@type": "Activity",
        "@id": "a9",
        "label": [{ "@value": "spark plasma sintering" }],
        "matprov:temperature": [{ "@value": "723 K" }],
        "matprov:pressure": [{ "@value": "65 MPa" }],
        "matprov:duration": [{ "@value": "5 min" }]
      },
      { "@type": "Usage", "activity": "a9", "entity": "e11" },
      { "@type": "Usage", "activity": "a9", "entity": "e15" },
      { "@type": "Generation", "activity": "a9", "entity": "e12" },
      {
        "@type": "Entity",
        "@id": "e12",
        "type": [{ "@value": "material" }],
        "label": [{ "@value": "spark plasma sintered sample" }]
      }
    ]
  }
]