微悬浮聚合法制备丙烯酸-丙烯酸正丁酯-丙烯酸甲酯共聚物纳米破乳剂

以丙烯酸(AA)、丙烯酸甲酯(MA)和丙烯酸正丁酯(BA)为单体,N,N-亚甲基双丙烯酰胺(MBA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,利用微悬浮聚合法制备了丙烯酸-丙烯酸正丁酯-丙烯酸甲酯共聚物(P(AA-BA-MA))。采用红外光谱和核磁共振对聚合物的结构进行了表征,分析了聚合物的粒径及其分布,测试了不同温度下聚合物在甲苯中的表面张力,探讨了丙烯酸丁酯含量对破乳性能影响,并综合考察了聚合物在原油乳液中的破乳性能。研究结果表明,P(AA-BA-MA)的平均粒径为83.81 nm,在甲苯溶液中能有效降低表面张力;随着丙烯酸丁酯含量增加,对原油乳液具有良好的破乳性能;当单体质量比m(AA)∶m(MA)∶m(BA)=3∶1∶6、破乳温度70℃和破乳剂浓度为100 mg/L以上时,破乳效率可达到85.91%以上,能快速高效地实现油水分离,且水相清亮,油水界面整齐。

能力与品德同步培养的有机化学课程教学改革与实践

立足于新时期对本科教学所提出的更高要求,探索了能力与品德同步培养的有机化学课程改革与实践,将课程育人–知识育人–实践育人的新方法和新理念体现在有机化学教学的各个环节,创造性地将教书和育人进行有机结合。在知识培养的同时还注重对学生创新思维的培养,引导学生养成勤思考、善思考的习惯,而且更重要的是强化对学生品性修为的塑造,为高校专业课程的改革提供有益的参考。

小骨窗开颅手术对高血压脑出血患者临床疗效及预后的影响

目的探讨小骨窗开颅手术治疗对高血压脑出血患者临床疗效及预后的影响。方法选取2018年1月~2021年1月本院收治高血压脑出血患者124例。根据治疗方案分为对照组(颅骨去骨瓣减压术)61例和试验组(小骨窗开颅手术)63例。观察两组临床疗效;通过日常生活能力评分(Activity of Daily Living Scale,ADL)及美国国立卫生院神经功能缺损(National Institutes of Health Stroke Scales,NIHSS)评分、格拉斯预后评分评估预后情况。结果试验组临床总有效率92.06%(58/63),对照组70.48%(43/61),差异有统计学意义(P<0.05);治疗后,试验组ADL评分和格拉斯预后评分高于对照组,NIHSS评分低于对照组(P<0.05)。结论小骨窗开颅手术治疗高血压脑出血患者,能提升生活能力及改善预后。

Research on the Informatilization of the Small-medium Sized Technological Enterprise in China

The paper analyses the necessity and importance of enterprise informatilization in Small-medium Sized technological enterprises in China. Considering the problems existing in the informatilization, the authors suggest that some problems and countermeasures be paid special attention when the enterprises promote their survival and development by informatilization.

Experimental research on affecting factors of the cutting quality of sugarcane harvesters under complicated excitations

The sugarcane field excitation,cutting forces and the engine excitation constitute complicated excitations acting on sugarcane harvesters.In this study,the sugarcane cutting mechanism under complicated excitations was analyzed.The dynamics and the mathematical models of sugarcane harvesters were established and simulated.Based on theoretical analysis,sugarcane cutting experiments were done on a self-built sugarcane harvester test platform(SHTP),designed as single-factor and the orthogonal experiments.Effects of the sugarcane field excitation characterized by the sugarcane field excitation device(SFED)output frequency,the engine excitation characterized by the actuating engine output frequency,the cutter rotating speed,the sugarcane harvester travelling speed simulated through the sugarcane transporting speed of the SHTP and the cutter inclination angle on the cutting quality of sugarcane harvesters were studied.Effects of the axial cutter vibration on three-directional cutting forces and the sugarcane cutting quality(SCQ)as well as effects of three-directional cutting forces on the SCQ were further studied.It is shown that the sugarcane field excitation,the axial cutter vibration amplitude and frequency as well as the three-directional cutting forces have significantly negative monotonic correlated effects on the SCQ while the cutter rotating speed,the sugarcane harvester travelling speed and the cutter inclination angle have significantly positive monotonic correlated effects on the SCQ.Significance levels of effects on three-directional cutting forces and the SCQ form high to low are as follow,the axial cutter vibration,the sugarcane field excitation,the cutter rotating speed,the engine excitation,the cutter inclination angle,the sugarcane harvester travelling speed.The theoretical analysis results were verified through experiment and an optimal combination was obtained with the cutter rotating speed of 700 r/min,sugarcane harvester travelling speed of 0.6 m/s and cutter inclination angle of 8º.This study can provide a reference for setting cutting parameters of sugarcane harvesters with a good SCQ.

Targeting a cryptic allosteric site of SIRT6 with small-molecule inhibitors that inhibit the migration of pancreatic cancer cells

SIRT6 belongs to the conserved NAD^(+)-dependent deacetylase superfamily and mediates multiple biological and pathological processes.Targeting SIRT6 by allosteric modulators represents a novel direction for therapeutics,which can overcome the selectivity problem caused by the structural similarity of orthosteric sites among deacetylases.Here,developing a reversed allosteric strategy Allo Reverse,we identified a cryptic allosteric site,Pocket Z,which was only induced by the bi-directional allosteric signal triggered upon orthosteric binding of NAD^(+).Based on Pocket Z,we discovered an SIRT6 allosteric inhibitor named JYQ-42.JYQ-42 selectively targets SIRT6 among other histone deacetylases and effectively inhibits SIRT6 deacetylation,with an IC50 of 2.33μmol/L.JYQ-42 significantly suppresses SIRT6-mediated cancer cell migration and pro-inflammatory cytokine production.JYQ-42,to our knowledge,is the most potent and selective allosteric SIRT6 inhibitor.This study provides a novel strategy for allosteric drug design and will help in the challenging development of therapeutic agents that can selectively bind SIRT6.

A Photocaged Azidosugar for Light-Controlled Metabolic Labeling of Cell-Surface Sialoglycans

The photocaging strategy has been widely used for activating biomolecules and hence regulating the underlying biological processes with high temporal and spatial resolution.Herein,we integrate this strategy into metabolic glycan labeling,which enables optical-ly-controlled metabolic labeling of cell-surface sialoglycans with azides.N-Azidoacetylmannosamine(ManNAz)is caged with a 4,5-dimethoxy-2-nitrobenzyl(DMNB)group at the anomeric hydroxyl group to block its cellular metabolism.After feeding to the cells,irradiation with 365 nm UV light or 405 nm visible light cleaves the photocage and generates ManNAz within the cells.ManNAz is metabolically converted to azido sialic acid,which is then incorporated into cell-surface sialoglycans.We demonstrated spatial and temporal control of this strategy by specifically labeling sialoglycans on a single cell and tracking the metabolism of ManNAz based on light-triggered pulse-chase labeling,respectively.The light-controlled metabolic glycan labeling strategy should facilitate probing of glycosylation in complex biological systems with high spatiotemporal precision.