摘要：As a small catalytic DNA molecule, 10-23 DNAzyme has cleavage ability against complementary RNA. Previous studies of chemical modification have shown that its catalytic core can be further optimized in order to obtain more powerful catalytic ability. The analogues of 2＇-deoxyadenosine （5） and 2＇-deoxyguanosine （6） could improve the cleavage ability of the DNAzyme when positioned at positions A9, （32 and G14 in the catalytic core, respectively. Moreover, their combinatorial incorporations were studied, the results implicated that the effect was position-dependent, and positive additive results could be achieved at some positions. The highly conserved G1, G2 and G14 could be optimized by single or combinatorial modification with 2＇-deoxyguanosine analogues. Chemical modifications on the functional groups of the core residues would be a feasible approach for the optimization of 10-23 DNAzyme.

摘要：通过基础地质特征、开发层系划分、开采井井型确定、井网优选、合理井距计算等要素分析,对沁端区块煤层气开发方案进行研究。沁端区块主力煤层为3号和15号,区块地质构造简单,煤储层非均质性较弱,两套煤层流体性质、压力系统一致、生产能力相仿,可作为一套开发层系,适合采用水平井开采,井网部署可参照五点布井法。通过开发层系划分,优选的开采井型、井网及井距的分析,设计出4种开发方案,根据国内现有的开采技术水平,并通过数值模拟,对4种开发方案的累计产气量、采收率、经济效益等进行预测和评价,确定145口直井和20口水平井两种井型搭配投入生产,总支出较少且采收率较高,最终采收率达可42.25%,整体利润较大,是沁端区块煤层气最佳的开发方案。