Stability of loess high-fill slope based on monitored soil moisture changes

This paper aims to assess the influence of moisture content changes during rainfall on the stability of loess high-fill slopes by taking a loess high-fill slope in Lanzhou City as an example.First,according to the moisture content monitoring data collected from a slope online monitoring system,direct shear tests were performed on soil samples of different moisture content to determine the relationship between the shear strength parameters and moisture content.Next,a coupled hydro-mechanical model with soil shear strength related to moisture content was established and used to analyze 16 working conditions with various rainfall intensities and durations for two cases:shear strength parameters from the site exploration report and those from this study.Finally,the results from the two cases were compared regarding the changes in stresses and displacements after rainfall infiltration to analyze the influence of moisture content on the stability of loess high-fill slopes.The conclusions are as follows:(1)Segmental relationship equations of cohesion and angle of internal friction were established for loess with various moisture content.(2)Under the conditions of different rainfall intensities,significant differences were observed in the trends of slope stress and displacement changes.(3)The slope displacement occurred in the shallow soil layer within about 12.5 m from the slope top,and the plastic strain concentrated in the soil layer within about 6 m from the slope top.(4)The results of slope stability analyses based on moisture content monitoring data are more in line with the observed.

湿度监测对地下构造物墙面病害的影响分析

随着地区环境的变迁,在自然和人为不利因素的影响下,地下构造物内部渗水严重,水害普遍发育,并衍生出墙面颜料褪色、表层风化剥落等多种衍生病害,且病害发展速度惊人,已经严重威胁到墙面的安全和长久保存,继续进行抢救性保护。通过对地下构造物受到的湿度影响进行,找出相应措施,从而实现对墙面的保护。

A novel ferroelectric based on quinuclidine derivatives

The compound[(CH3)2 CH-C3 H17 N][CoBr4](1)based on quinuclidine derivatives was achieved by the solution synthetic method and characterized by elemental analysis,infrared spectroscopy,single-crystal X-ray structural analysis and dielectric measurement,respectively.Variable-temperature single-crystal X-ray diffraction suggested that the compound unde rwent the phase transition from the space group C2/c to Cc.The polarization curve was measured using the Sawyer-Tower circuit.The structural phase transitions of 1 was ascribed to the distortion of a[(CH3)2 CH-C3 H17N]2+cation from this inorganicorganic hybrid material[(CH3)2 CH-C3 H17N][CoBr4].The strong change in dielectric anomalies makes compound 1 a suitable candidate for promising switchable dielectric materials.This work represents a feasible strategy thought for the targeted harvesting of low temperature ferroelectrics.

5-HT_(3) receptor antagonists protect against pressure overload-induced cardiac hypertrophy in murine

Activation of cardiac sympathetic afferent reflex results in the increase of sympathetic activity.Serotonin(5-HT)activates cardiac sympathetic afferent through stimulating 5-HT_(3) receptors,the aim of present study is to test whether 5-HT_(3) receptor antagonists protect against cardiac hypertrophy.Cardiac hypertrophy induced by TAC for 4 weeks in mice was significantly inhibited by administration of 5-HT_(3) receptor antagonists,ondansetron(2.5 mg/kg,ip.)or tropisetron(2.5 mg/kg,ip.).Histological analysis revealed that the increased cardiac fibrosis in hypertrophic heart was relieved by ondansetron or tropisetron treatment.Ondansetron or tropisetron reduced the elevated plasma level of noradrenalin in mice with cardiac hypertrophy.Ondansetron and tropisetron had no effect on cardiomyocte hypertrophy induced by phenylephrine treatment in vitro.Finally,we took tropisetron as the representative drug and examined the effects of tropisetron on the desensitization of cardiac b-adrenergic receptor in rat treated with abdominal aortic banding(AB).Results showed that tropisetron restored the desensitization of cardiac b-adrenergic receptor in AB-treated rats.In conclusion,5-HT_(3) receptor antagonists protected against cardiac hypertrophy and restored the desensitization of cardiac adrenergic responsiveness,the mechanism in which may be through reducing the sympathetic activity.