Abstract: The present disclosure relates to the field of Fischer-Tropsch synthesis reaction catalysts, and discloses a pure phase ?/?? iron carbide catalyst for Fischer-Tropsch synthesis reaction, a preparation method thereof and a Fischer-Tropsch synthesis process, wherein the method comprises the following steps: (1) subjecting the nanometer iron powder or a nano-powder iron compound capable of obtaining the nanometer iron powder through in-situ reduction and H2 to a surface purification treatment at the temperature of 250-510° C.; (2) pretreating the material obtained in the step (1) with H2 and CO at the temperature of 80-180° C., wherein the molar ratio of H2/CO is 1.2-2.8:1; (3) carrying out carbide preparation with the material obtained in the step (2), H2 and CO at the temperature of 180-280° C., wherein the molar ratio of H2/CO is 1.0-3.0:1.

Abstract: The present disclosure relates to the field of Fischer-Tropsch synthesis reaction catalysts, and discloses a pure phase ?/?? iron carbide catalyst for Fischer-Tropsch synthesis reaction, a preparation method thereof and a Fischer-Tropsch synthesis process, wherein the method comprises the following steps: (1) subjecting the nanometer iron powder or a nano-powder iron compound capable of obtaining the nanometer iron powder through in-situ reduction and H2 to a surface purification treatment at the temperature of 250-510° C.; (2) pretreating the material obtained in the step (1) with H2 and CO at the temperature of 80-180° C., wherein the molar ratio of H2/CO is 1.2-2.8: 1; (3) carrying out carbide preparation with the material obtained in the step (2), H2 and CO at the temperature of 180-280° C., wherein the molar ratio of H2/CO is 1.0-3.0: 1.

Abstract: The present disclosure provides atomic structures of Cas9 with and without polynucleotides bound thereto. Also provided is a computer-readable medium comprising atomic coordinates for Cas9 polypeptides in both an unbound configuration and a configuration wherein the Cas9 polypeptide is bound to one or more polynucleotides. The present disclosure provides crystals comprising Cas9 polypeptides; and compositions comprising the crystals. The present disclosure provides methods for the engineering of Cas9 polypeptides wherein Cas9 activity has been altered, ablated, or preserved and amended with additional activities.

Abstract: The present disclosure provides atomic structures of Cas9 with and without polynucleotides bound thereto. Also provided is a computer-readable medium comprising atomic coordinates for Cas9 polypeptides in both an unbound configuration and a configuration wherein the Cas9 polypeptide is bound to one or more polynucleotides. The present disclosure provides crystals comprising Cas9 polypeptides; and compositions comprising the crystals. The present disclosure provides methods for the engineering of Cas9 polypeptides wherein Cas9 activity has been altered, ablated, or preserved and amended with additional activities.