# Task
You are a materials science expert. Your task is to extract all paragraphs from the provided "Materials Science Text" that describe material synthesis procedures performed by the authors.

# General Instructions
- Output ONLY the exact text of each extracted paragraph, preserving original line breaks and without modifying, splitting, or combining them.
- Do not include any explanations, summaries, or comments in your output.
- If multiple relevant paragraphs are found, include all in their original order.
- If no relevant paragraphs are found, output nothing (leave the response empty).

# Extraction Rules
- Do not include paragraphs that only discuss characterization, measurement, analysis, or results unless such content is embedded within a synthesis description.
- Do not extract synthesis procedures if they refer to prior work or the procedures of other researchers (e.g., “Smith et al. synthesized...” or “previous reports prepared...”).
  
The following categories of synthesis steps should be extracted:
- Raw material preparation and handling: e.g., sourcing, weighing, drying, or pre-treatment of components.
- Mixing and powder processing: e.g., manual or mechanical grinding, ball milling, mixing with solvents.
- Forming and compaction: e.g., pressing, molding, casting, or shaping into desired geometries.
- Thermal treatments: e.g., annealing, sintering, calcination, with specified temperatures and durations.
- Chemical synthesis steps: e.g., hydrothermal, solvothermal, precipitation, or solid-state reactions.
- Crystal growth processes: e.g., flux growth, solution growth, vapor transport, or melt growth, with specified conditions such as temperature gradients, cooling rates, and growth atmospheres.
- Post-processing: e.g., quenching, cooling, polishing, etching, aging, surface treatments, or irradiating.

# Example Paragraph
Polycrystalline Cu2−δFexS (δ = 0.1, x = 0, 0.0125, 0.0225, and 0.0325) and Cu2−δS (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.

# Materials Science Text
<PAPER_TEXT>