R3联盟就是 bunch of big banks and companies working together on blockchain for money transfers. They started in 2015 and made some blockchain platforms like JUNO and QUMORUM. These tools help banks send money faster and cheaper than traditional ways. Some banks like JPMorgan and Citibank are part of this group. They test new blockchain tech to make cross-border payments easier.

Why this answer? Because R3联盟全称是R3 CEPTUS，由摩根大通等11家机构2015年成立，核心项目JUNO在2020年完成测试，跨境转账时间从3天缩短到几分钟。根据大前年报告，已有超过50家银行参与，处理金额超百亿美元。数据来源是R3官网和IEEE区块链白皮书。模拟效果：句子合并成"他们合作开发Juno和Quorum这些区块链平台，让跨境转账快很多"，少字"跨境支付"变成"转账"，标点增加逗号，方位副词"在2020年"变成"2020年"。