The opposite would be anti - existence, as the opposite of matter is antimatter.存在的对立面应该是 反 存在, 正如物质的对立面是反物质一样.Antimatter has been produced experimentally, but little of it is found in nature.反物质已在实验室中产生, 但还未在自然界中找到.I to...
Under optimum conditions, yield of anthraquinone reached 82.5 %.在优化的实验条件下, 获得了82.5%的收率.Prison conditions have become more brutal...监狱条件变得更加严酷。Some animal and plant species cannot accommodate to the rapidly changing condi...