ISO 16000-9标准描述
ISO 16000-9 Indoor air - Part 9: Determination of the emission of volatile organic compounds from samples of building products and furnishing - Emission test chamber method
ISO 16000-9室内空气-第9部分:建筑产品和家具中挥发性有机化合物排…
总结:
这段代码实现了一个泛型单例模式(Singleton Pattern),用于确保某个类(由泛型参数 T 指定)在整个应用程序中只有一个实例,并且在第一次访问时才创建该实例。该模式保证了该实例的全局唯一…
As consumers have shifted their attention from stationary media to perpetual media on the go,traditional advertising lost some of its appeal. ecosystem 生态环境 dominate 统治,支配 stationary 稳定的,不变的 perpetual 不间断的;持续的 pivot 转动 pivot investme…