Rau ntau kev lag luam, kev siv cov nyiaj siv hydrocarbon tau dhau los ua ib feem tseem ceeb ntawm lawv cov haujlwm. Cov khoom siv no muaj ntau cov ntawv thov suav nrog cov nplaum, cov tshuaj pleev xim, inks thiab cov tshuaj pleev ib ce. Raws li ib tug ua chaw tsim khoom lag luam ntawm hydrocarbon resins, Tangshan saim ...
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