Amending cultures of selenium-resistant bacteria with dimethyl selenone

A possible biological intermediate in the reduction and methylation of selenium oxyanions, dimethyl selenone, was synthesized, and the first experiments involving the amendment of selenium resistant bacterial cultures with this compound are reported. The amount of volatile, reduced selenium-containing species released from these cultures into the headspace is significantly more than that produced in analogous experiments involving sodium selenate amended cultures. Dimethyl selenone is reduced in the presence of dimethyl sulfide and dimethyl disulfide in a complex growth medium, trypticase soy broth with 0.1% nitrate. This reduction occurs whether or not the reduced sulfur compounds are biologically produced.     

Research on an amendments measurement method on projectile burst location

In shooting range, projectile burst location is an important indicator. To solve the question that multi-screens across measure method cannot gain projectile proximity fuze burst location parameters when projectile close to simulation object at high altitude, the method of lateral camera assistant multi-screens across was proposed to amend the coordinates of four screens across system and realize projectile proximity fuze burst three-dimensional coordinates. The principle and existed question of four screens across system in measuring projectile burst coordinate were analyzed, and according to their measure shortcomings, the calculation model of lateral camera assistant four screens across system was set up, its amendment arithmetic was educed and analyzed, at last, the amendment three-dimensional coordinates of projectile burst location was give out based on their space geometry relation, and the measure errors were analyzed. Through experiment, the amendment measure projectile proximity fuze burst three-dimensional coordinates arithmetic was validated, and the results show the amendments measurement method is scientific and feasible.     

高教版《基础有机化学》中两个还原反应机理的修正与补充

在教学过程中发现高等教育出版社出版的《基础有机化学》一书中有两个经自由基负离子的还原反应(即炔烃用碱金属和液氨还原反应和Birch(伯奇)还原反应)机理有不妥和需要完善之处,对此进行了修正与补充。     

软X光多层镜反射率的标定与修正

在北京同步辐射装置上,利用3W1B 束线得到了21° B4C/Si,21° B4C /Mo,10° Cr/Ti,15° B4C/W,10° B4C/W以及6.86° B4C/W等多层镜在50～1500 eV能段上的反射率标定曲线.分析了标定结果的不确定度,计算得到多层镜的积分衍射效率,并修正了标定结果.