植入左束支起搏模式双腔抗核磁起搏器1例的护理

患者男,13岁。心脏扩大12年,心跳慢7年5个月,病程中多次心电图提示三度房室传导阻滞、交界性逸搏心律、完全性左束支传导阻滞(图1),经胸超声心动图显示:心脏左心室内径明显增大(LV 6.28 cm),左心房内径增大(LA 3.92 cm),左心室收缩功能(LVEF)50%,室间隔(IVS 0.75 cm)。室壁运动分析:室间隔心肌与左心室心肌运动不同步,室间隔中下段心肌偏向右心室,动度减低;左心室下壁心肌动度减低。

抗核磁双冗余CAN总线电缆的研制

为了满足航空领域液压控制系统的信息传输需求,自主开发了一款抗核磁双冗余控制器局域网络(CAN)总线电缆。该抗核磁双冗余CAN总线电缆导体采用直流电阻较小的镀银铜绞线;绝缘采用低介质损耗的交联聚乙烯,降低电缆的衰减;绝缘线芯采用特殊处理,增强电缆的机械性能和耐热性能;屏蔽采用多层组合式屏蔽结构,增加电缆的屏蔽效能,提高电缆的抗核电磁脉冲干扰性能;护套采用聚氨酯弹性体,起到防护作用和确保电缆方便用户使用和安装敷设。经检测,该抗核磁双冗余CAN总线电缆具备优异的CAN总线系统线路传输功能、抗核电磁干扰环境功能、双冗余备份系统功能,可满足航空液压控制系统用抗核磁双冗余CAN总线系统的使用要求,提高了系统的容错能力和可靠性。

~1H and ^(13)C NMR Assignments for Amlodipine and Risperidone

Aim To investigate the NMR spectroscopy of amlodipine and risperidone.Methods 1D NMR and 2D NMR experimental techniques of gCOSY, gHSQC and gHMBC were wsed. Results Theassignments of the ~1H and ^(13) C NMR data for the two drugs were performed and confirmed by theevidence of J_(HF) and J_(CF). Conclusion The structures of amlodipine and risperidone wereconfirmed by careful analysis of regular 1D and 2D NMR spectroscopy.

Hydration phase and pore structure evolution of hardened cement paste at elevated temperature

To understand the effect of steam curing temperature on the hydrate and microstructure of hardened cement paste,several measuring methods including X-ray diffraction(XRD),atomic absorption spectroscopy(ASS),ion chromatography,conductivity meter,alternating-current impedance spectroscopy and nuclear magnetic resonance(NMR)are employed to investigate the hydration characteristics,pore solution composition and conductivity,resistivity and pore structure during the steam curing process.Experimental results show that steam curing promotes the hydration process,greatly raises the resistivity,and decreases the porosity of specimen at early age.Compared with being treated at 45℃,higher temperature leads to a fast decomposition of ettringite at initial stage of the constant temperature treatment period,which improves the relative content and ionic activity of the conductive ions in pore solution.Furthermore,the number of pores larger than 200 nm increases significantly,which reduces the resistivity of the hardened cement paste.Cement paste treated at 45℃ has a more stable and denser microstructure with less damages.

Experimental investigation on the relevance of mechanical properties and porosity of sandstone after hydrochemical erosion

Under the effect of chemical etching,the macroscopic mechanical properties,mesoscopic structure,mineral content,and porosity of rocks undergo significant changes,which can lead to the geological disasters; thus,an understanding of changes in the microscopic and macroscopic structure of rocks after chemical etching is crucial.In this study,uniaxial mechanical tests and nuclear magnetic resonance(NMR) spectroscopy were carried out on sandstone samples that had been previously subjected to chemical erosion under different p H values.The aim was to study changes in properties and mechanical characteristics,including deformation and strength characteristics,of the rock,and microscopic pore variation characteristics,and to perform preliminary studies of the chemical corrosion mechanism.Results show that different chemical solutions have a significant influence on the uniaxial compressive strength,the axial strain corresponding to the peak axial stress,elastic modulus,etc.With the passage of time,porosity increases gradually with exposure to different chemical solutions,and exposure to chemical solutions results in large changes in the NMR T2 curve and T2 spectrum area.Sandstone exposed to different chemical solutions exhibits different corrosion mechanisms; the root cause is the change of mineral.

Synthesis and Antimicrobial Activity of Heterocyclic Compounds Containing Chromene Ring

Synthesis of some new compounds containing chromene ring are described in this work. They were synthesized in moderate to good yield, started with Condensation of 7-hydroxy-4-methylcoumarin （1） with ethyl bromoacetate furnishes ethyl-2-（4-methyl-2-oxo-2H-chromen-7-yloxy） acetate （2）. The structures of all the new compounds were confirmed using IR, 1H-NMR spectra and micro analysis, selected members of the synthesized compound were screened for antimicrobial activity. They have shown a wide range of activity from one completely inactive compound to medium active ones.

Synthesis and antiviral bioactivities of novel chiral bis-thiourea-type derivatives containing α-aminophosphonate moiety

Starting from 1-((1R,2R)-2-aminocyclohexyl)-3-substituted thioureas (3a–c) and substituted isothiocyanates (9a–d),chiral bis-thiourea derivatives containing α-aminophosphonate moiety 10a–l were prepared and completely characterized by elemental analysis,physical and spectral (IR,1H NMR,13C NMR,31P NMR) data.The results of bioassay revealed that compounds 10a and 10e possessed appreciable curative bioactivities on cucumber mosaic virus (CMV) at 0.5 mg/mL in vivo (inhibitory rate = 60.3%,64.8% respectively) and tobacco mosaic virus (TMV) at 0.5 mg/mL in vivo (inhibitory rate = 50.3%,50.8% respectively),which were comparable to the values shown by standard reference (58.7%) and commercial product Ningnanmycin (56.3%),respectively.Chiral compound 10e displayed more potent antiviral activity (EC50 = 0.149 mg/mL) than Ningnanmycin (EC50 = 0.201mg/mL) against CMV.