Synthesis and protein tyrosine phosphatase 1B inhibition activities of two new synthetic bromophenols and their methoxy derivatives

3-bromo-4,5-bis(2,3-dibromo-4,5-dihydroxybenzyl)-1,2-benzenediol (1) is a natural bromophenol isolated from the red algae Rhodomela confervoides that exhibits significant inhibition against protein tyrosine phosphatase 1B (PTP1B). Based on its activity, we synthesized two new synthetic bromophenols and their methoxy derivatives from vanillin using the structure of natural bromophenol 1 as a scaffold. The structures of these bromophenols were elucidated from 1H NMR, 13C NMR, and high resolution electron ionization mass spectrometry as 2,3-dibromo-1-(2p-bromo-6p-(3q,4q-dimethoxybenzyl)- 3p,4p-dimethoxybenzyl)-4,5-dimethoxybenzene(2),2,3-dibromo-1-(2p-bromo-6p-(2q-bromo-4q,5q-dimethoxy-benzyl)-3p,4p-dimethoxybenzyl)-4,5-dimethoxybenzene(3),3,4-dibromo-5-(2p-bromo-6p-(2q-bromo-4q,5q-dihydroxybenzyl)-3p,4p-dihydroxybenzyl)pyrocatechol(4)and 3,4-dibromo-5-(2p-bromo-6p-(3q,4q-dihydroxybenzyl)-3p,4p-dihydroxybenzyl)pyrocatechol (5).PTP1B inhibition activities of these compounds were evaluated using a colorimetric assay,and compounds 3 and 4 demonstrated interesting activity against PTP1B.     

基于SBAS/PS-InSAR技术的滑坡遥感监测对比研究

以2015~2019年12景ALOS-2 PALSAR2影像和2018~2019年38景Sentinel-1A影像为主要数据源,利用PS-InSAR和SBAS-InSAR技术提取西藏江达县波罗乡白格滑坡点的形变信息,并对处理结果进行交叉验证。研究得到以下结论：1）PS-InSAR技术条件下,ALOS-2数据和Sentinel-1A数据的平均形变速率范围为-68.9~37.9 mm/a和-64.5~24.2 mm/a;SBAS-InSAR技术条件下,ALOS-2数据和Sentinel-1A数据的平均形变速率范围为-84.2~-40.0 mm/a和-84.0~-13.0 mm/a。2）对2种数据结果中提取的4个特征点进行时序分析和定量分析显示,2种InSAR技术结果变化趋势较为一致,验证了两者在滑坡监测中的可靠性和准确性。     

基于InSAR技术的江苏水闸垂直位移监测方法可行性探讨

利用Sentinel-1雷达卫星影像,探讨InSAR技术作为水闸垂直位移变形监测辅助手段的可行性.结果 表明,InSAR技术与水准测量相比,两种方法得到的水闸垂直位移变化趋势基本一致;InSAR测量结果具有可信性,后续可进一步推广应用.     

InSAR特征点分布与土地用途的关系研究

本文以广州为研究区域,选取72景具有两种极化模式(VV&VH)数据的Sentinel-1A卫星影像,获取区域内的永久性散射体(Permanent Scatterer,PS)和分布式散射体(Distributed Scatterer,DS),并结合Landsat-8卫星影像的土地利用类型分类结果,研究广州市的土地利用类型...     

Effect of Penetration Rates on the Piezocone Penetration Test in the Yellow River Delta Silt

Partial drainage often occurs during piezocone penetration testing on Yellow River Delta silt because of its intermediate physical and mechanical properties between those of sand and clay.Yet,there is no accurate understanding for the range of penetra-tion rates to trigger the partial drainage of silt soils.In order to fully investigate cone penetration rate effects under partial drainage condi-tions,indoor 1 g penetration model tests and numerical simulations of cavity expansion at variable penetration rates were carried out on the Yellow River Delta silt.The boundary effect of the model tests and the variation of key parameters at the different cavity ex-pansion rates were analyzed.The 1 g penetration model test results and numerical simulations results consistently indicated that the penetration rate to trigger the partially drainage of typical silt varied at least three orders of magnitude.The numerical simulations also provide the reference values for the penetration resistance corresponding to zero dilation and zero viscosity at any given normalized penetration rate for silt in Yellow River Delta.These geotechnical properties can be used for the design of offshore platforms in Yel-low River Delta,and the understanding of cone penetration rate effects under the partially drained conditions would provide some technical support for geohazard evaluation of offshore platforms.     

利用JCZ-1T地震计BB通道观测数据检测地球自由振荡

采用库尔勒台JCZ-1T地震计BB通道垂直向的观测数据,利用功率谱密度估计方法,在没有对观测资料进行任何改正的情况下,获取2016-03-02印尼苏门答腊岛海域7.8级和2016-04-17厄瓜多尔7.5级大地震激发的0S7～0S60基频球型自由振荡,并与PREM模型理论值进行对比分析。结果表明,实测值与理论值相吻合,除部分振型与理论值偏差较大以外,其余振型与理论值偏差均小于0.1％。印尼苏门答腊岛海域7.8级地震所检测的球型振荡能量频谱分布及振型与厄瓜多尔7.5级地震所检测的球型振荡有一定差别,前者所能检测的振型数量相对较多。     

江西省都昌县山地与平原植被界线提取

由于生长环境、地带性分布规律和垂直差异,山地与平原地区的不同植被类型在遥感影像上存在“同物异谱”及“异物同谱”现象,易导致土地类型的误分。为避免此类错分,在进行土地覆被类型解译之前,应首先确定平原、山地植被的边界。本文在遥感影像聚类分析、GIS空间分析及数理统计分析技术的支持下,以江西省都昌县北部地区为研究区域,基于高分一号（GF-1）遥感卫星影像及地形要素,完成了山地植被与平原植被的界线提取。实验结果显示,本研究得到的植被界线精度高达99.47%和96.28%。与单纯基于遥感影像分类得到的植被边界成果相比,精度提高了近25%和23%。研究证明,高分辨率遥感影像与地形因子结合后,计算得到的山地平原划分界线精度有明显提高,可以满足高分辨率遥感影像土地覆被类型解译研究的需要。     

时序InSAR技术在吹填人工岛礁沉降监测中的应用

采用2020-03～2022-03覆盖海南省儋州市海花岛的25景Sentinel-1A影像,分别运用SBAS-InSAR(small baseline subset InSAR)和PS-InSAR(permanent scatter InSAR)技术反演人工岛礁地面形变时空演变规律,开展重点沉降区域形变机理分析,探讨岛礁地面形变与海平面变化之间的相关性。结果表明：1)2种方法所得结果的空间分布和形变趋势表现出较高的一致性;2) SBAS-InSAR雷达视线向平均形变速率为-14.69～6.96 mm/a,最大累积沉降量为-37.18 mm; 3)岛礁靠近外海侧区域沉降速率远大于靠近陆域侧区域,其形变趋势受海洋水动力扰动和地下水位变化影响,具有此类形变特征的地面形变与海平面变化存在一定相关性。     

基于HY-1C卫星的呼伦湖蓝藻遥感监测及对比研究

随着全球变暖以及人类活动加剧,呼伦湖已经连年夏季暴发藻华,破坏湖泊生态。海洋一号C(HY-1C)卫星作为中国首颗海洋水色业务卫星,搭载的海岸带成像仪(CZI)在水体环境监测中正发挥越来越重要的作用。随着搭载有相同传感器的HY-1D卫星发射,双星组网观测,可形成3天两次高频次、大范围的观测能力,尤其在水体漂浮藻类等目标探测方面具备优异的效能。本文基于2022年7月19日的HY-1C卫星CZI载荷数据,计算VB-FAH指数来检测藻华,并结合OTSU阈值分割算法对呼伦湖蓝藻暴发进行遥感识别。主要结论如下:结合目视解译结果,对自动分类结果进行精度评价,其中精度指标最高的仅相差2.53%,最低的相差7.60%,总体情况较好;对不同影像分割方法进行对比,其中OTSU阈值分割算法和K-Means算法结果几乎一致,LVQ算法结果差异较大。