拉西瓦水电站700 MW巨型水轮机转轮现场制造及质量控制

拉西瓦水电站安装6台700 MW水轮发电机组,水轮机转轮采用现场加工制造方案。从进货检验、现场装配、整体加温预热、焊接、焊后消应、转轮加工、静平衡试验等方面论述了拉西瓦水电站水轮机转轮的现场加工制造及质量控制。对加工工序、工艺及质量进行了全面的检查、检测,结果表明,工地现场制造的水轮机转轮各项指标均达到优良等级,制造质量完全满足设计及合同要求。

O-Alkylation of Chitosan for Gene Delivery by Using Ionic Liquid in an in- situ Reactor

An in-situ reactor was elaborately designed for O-alkylation of chitosan in an ionic liquid ([BMIM]Cl) solvent, using N, N'-carbonyldiimidazole? as bonding agent. The original chitosan and the modified chitosan were characterized by FT-IR and XRD analysis. FT-IR spectra revealed that the alkylation of chitosan selectively occurred at hydroxyl groups, with unprotected amino groups untouched. It was proposed that the particular properties of the ionic liquid solvent should be responsible for the selectively alkylation. The result from X-ray diffraction showed that the crystallinity of O-alkylation of chitosan decreases, most likely due to the decomposition of CS in the ionic liquid. The solubility test of O-alkylated chitosan in aqueous HAc solution (w/w: 0.1%) confirmed that the product could be easily dissolved in aqueous HAc solution because of its abundant free amino groups. It was suggested that the O-alkylated chitosan was suitable for the coming cell transfection test in vitro.

某工程现浇混凝土楼板裂缝的成因及处理措施

以某工程混凝土楼板开裂为例,对混凝土楼板开裂原因进行了分析,指出大风降温且养护不周是产生裂缝的主要原因;分析了裂缝对混凝土楼板造成的影响,此裂缝一般不影响结构的强度,但降低了结构的耐久性,影响了混凝土的外观质量。本工程用抹灰修补裂缝获得了较好的效果。