天津基金是中国政府设立的一种政府引导基金，旨在促进天津市的经济发展和产业升级。该基金由天津市人民政府、国家发展和改革委员会、国家财政部等部门共同发起设立，总规模为人民币100亿元。

天津基金的发行时间尚未确定，具体发行时间将根据市场需求和基金筹备情况而定。一般来说，政府引导基金的发行时间会受到多种因素的影响，如政策环境、市场环境、资金募集情况等。因此，投资者需要密切关注相关政策和市场动态，以便及时了解天津基金的发行时间和投资机会。

In English:

The Tianjin Fund is a government-led fund established by the Chinese government to promote economic development and industrial upgrading in Tianjin. The fund was jointly launched by the Tianjin Municipal Government, the National Development and Reform Commission, the Ministry of Finance, and other relevant departments, with a total size of RMB10 billion.

The issuance date of the Tianjin Fund has not been determined yet. The specific issuance date will be determined based on market demand and fund preparation. Generally, the issuance date of government-led funds can be affected by various factors, such as policy environment, market environment, and fundraising situation. Therefore, investors need to closely monitor relevant policies and market dynamics in order to timely understand the issuance date and investment opportunities of the Tianjin Fund.