罗马尼亚采购需求：铋纳米粉、铋纳米颗粒、铋粉、纳米铋金属粉、纳米金属、纳米材料

I'm looking to purchase Bismuth Nano powder, starting with an initial order of 250g. This will help me evaluate its quality and suitability for my needs. If the product meets my expectations, I would like to place a follow-up order for 1kg. Could you please provide the price per unit for the 250g and any discounts available for bulk purchases? Additionally, I'd appreciate details on the lead time for shipping and the payment options you offer. Thanks! Looking forward to your prompt response.