摘要：Based on the lead compound 1 reported in literature, a series of novel BACE1 inhibitors were designed and synthesized, among which compound 11 exhibited a 14-fold improvement in potency over the lead compound 1. This represents a good lead for the discovery of more promising BACE1 inhibitors for the potential treatment of AD.

摘要：By taking compound 1 as a lead, a series of 5-cyclopropyl substituted cyclic acylguanidine compounds were designed and synthesized as BACE1 inhibitors, compound 4d exhibited 84-fold improved inhibition efficiency than lead compound 1. The diphenyl fragment at the P3 position and the substituents at the second phenyl ring were essential for the compounds to achieve improved inhibition efficiency. This SAR studies provides new insights into the design and synthesis of more promising BACE1 inhibitors for the potential treatment of AD.

摘要：Based on the lead compounds 1 and 2, a series of novel BACE1 inhibitors were designed and synthesized,among which compound 9h exhibited a 60 fold improvement in potency over the lead compound 1. This represents a good lead for the discovery of more promising BACE1 inhibitors for the potential treatment of AD. The result also showed that the prop-2-yn-1-yloxy is a suitable fragment for modification of cyclic acylguanidine BACE1 inhibitors.

摘要：为提高红木余料的利用率,传承和发扬中国传统文化和广西少数民族特色文化,结合当代流行的消费观念,提出了一种将红木加工余料与文化相融合的设计方案,即将红木余料做成外观为爱心形状,且可磁吸的吊坠,并将十二生肖与广西少数民族特色纹样相结合后进行简化抽象,设计生成装饰图案。研究结果可为提高红木加工余料的附加值、充分发挥传统与民族文化魅力提供新思路,进而推动红木资源的高效利用和优秀文化的传承。

摘要：中国巡天空间望远镜(Chinese Survey Space Telescope,CSST)预计对系外行星开展大气观测研究,这为系外行星观测领域提供了新的机遇.目前主要通过凌星透射谱来研究系外行星大气.然而,实际观测数据中已经发现恒星活动存在的迹象,且结果表明难以准确约束恒星活动污染.所以,如何准确区分并剔除恒星活动污染是透射光谱学的一个重大挑战.因此,在选择透射谱观测目标进行跟进观测时,需要对潜在的恒星污染及其可区分性进行定量评估,这需要大规模的仿真来提供预期数据.利用多色测光法结合机器学习来判别系外气态行星大气透射谱中是否存在潜在的恒星污染,针对CSST的多通道相机(Multi-Channel Imager,MCI)设计能准确预判透射谱是否存在恒星污染的滤光片观测组合,可为后续系外行星大气观测目标的策略制定提供一定的参考.

摘要：高寒湿地是一个巨大的碳库,对于高原野生动物栖息和生态安全维护具有重要意义。当前研究主要集中在海拔4000 m以下,对于海拔>4000 m高寒湿地表层土有机碳的研究仍待加强。基于长江源海拔最高(平均海拔>4500 m)的查旦湿地20个监测点共60个样方的表层土采样化验,分析了高寒湿地表层土有机碳含量和有机碳占比的空间分布,并探究干流、南北岸支流的空间差异。结果表明查旦湿地表层土有机碳的含量在0.54%~18.47%之间,平均值为4.78%,在总碳含量中的占比高于80%,总碳、总有机碳在南北岸支流的空间相关性相反。研究加深了我们对高寒湿地表层土有机碳空间分布差异的理解,为进一步估算高海拔高寒湿地碳汇储量提供了前期探索和验证数据。

摘要：Effects of working parameters on performance characteristics of hydrostatic turntable are researched by applying the fluid-structure-thermal coupled ***-structure interaction(FSI)technique and computational fluid dynamics(CFD)method are both employed by this new model,and thermal effects are also *** turntable systems with a series of oil supply pressures,various oil recess depth and several surface roughness parameters are *** parameters,such as turntable displacement,system flow rate,temperature rise of lubrication,stiffness and damping coefficients,are derived from different working parameters(rotational speed of turntable and exerted external load)of the hydrostatic *** results obtained from this FSI-thermal model are presented and discussed,and theoretical predictions are in good agreement with the experimental ***,this developed model is a very useful tool for studying hydrostatic *** calculation results show that in order to obtain better performance,a rational selection of the design parameters is essential.

摘要：介绍了26万t/a混合碳四全加氢装置第3,4周期(第3周期为2022年7月—2023年9月,第4周期为2023年11月—2024年3月)的工业运行状况,并在中试评价装置上进行了镍系催化剂与钯系催化剂性能对比评价。结果表明:混合碳四全加氢装置在第3,4周期运行过程中,进料负荷和反应压力均低于设计值,床层压差处于较高水平,反应器入口温度和床层温升,氢气与碳四质量流量比与设计值偏差不大;混合碳四原料不饱和烃质量分数与设计值接近,但是炔烃和丁二烯质量分数显著高于设计工况,第3周期加氢产品合格时间仅为140 d。在反应压力为2.5 MPa,入口温度为40~60℃,新鲜料体积空速为1.0~1.5 h^(-1),加氢产品循环比为15~17 h^(-1),氢烃体积比为100∶1的条件下运行800 h后,与钯系催化剂相比,镍系催化剂入口平均温度降低了6.5℃,床层温升升高了15.9℃,加氢产品不饱和烃质量分数降低了2.03个百分点,不饱和烃总转化率增加了4.49个百分点,可满足工业装置运行要求。

摘要：针对城市水环境存在着生态脆弱、韧性不足问题,本文提出了岸水协同生态治理与修复思路。本文分享的原创基于城市水生态修复的水质深度净化人工湿地技术,突破人工湿地碳氧分配,提升了对低碳高氮水的净化效率,改善了河湖水质;滨水蓝绿空间耦合污染生态拦截技术,突破了蓝绿空间共建共治,实现了雨水径流污染源头生态拦截净化;阐明水生植物衰退和恢复重要机制,突破了水生境修复和水生植物恢复难题,实现了水生植物自组织恢复。本文集成了城市河湖岸水协同生态治理与修复关键技术体系及应用范式,解决了城市河湖生态脆弱问题,助力城市水生态系统恢复。上述成果已成功应用于水环境整治工程,取得了显著环境、社会和经济效益。

摘要：AIM： To identify the gene （s） related to the antagonistic activity of Enterobacter cloacae B8 and to elucidate its antagonistic mechanism. METHODS： Transposon-mediated mutagenesis and tagging method and cassette PCR-based chromosomal walking method were adopted to isolate the mutant strain （s） of B8 that lost the antagonistic activity and to clone DNA fragments around Tn5 insertion site. Sequence compiling and open reading frame （ORF） finding were done with DNAStar program and homologous sequence and conserved domain searches were performed with BlastN or BlastP programs at ***. To verify the gene involved in the antagonistic activity, complementation of a full-length clone of the anrFgene to the mutant B8F strain was used. RESULTS： A 3 321 bp contig around the Tn5 insertion site was obtained and an ORF of 2 634 bp in length designated as anrFgene encoding for a 877 aa polyketide synthase-like protein was identified. It had a homology of 83% at the nucleotide level and 79% ID/87% SIM at the protein level, to the admM gene of Pantoea agglomerans andrimid biosynthetic gene cluster （AY192157）. The Tn5 was inserted at 2 420 bp of the gene corresponding to the COG3319 （the thioesterase domain of type I polyketide synthase） coding region on BSF. The antagonistic activity against Xanthomonas oryzae pv. oryzae was resumed with complementation of the full-length anrFgene to the mutant B8F. CONCLUSION： The anrFgene obtained is related to the antagonistic activity of BS, and the antagonistic substances produced by B8 are andrimid and/or its analogs.