简介：Twonewsteroidalbitterprinciples,taccolanolideO,PhavebeenisolatedfromTaccasubflaellataandtheirstructureswereestablishedbyspectroscopicmethods.

简介：Forloadingandunloadingofboatsorshipsroundtheclock,theaccesschannelanditsexpandedpart-aportareexcavatedonthelagoonandoceanreefflatsinthetropicPacificoceanicislands.Withoutmoles,theaccesschannel-porttrapssedimentandfurthertransportsittotheoceanorlagoon,resultingincoastalerosion.Thewideunevenreefflatwithalargecatchmentareatendstocausetheformationoftidecurrentsinthechannel-port,whilestrongwavesonthenarrowevenreefflatcangiverisetoripcurrents.Anaccesschannel-portwithamoleononesideortwomolesonbothsidesresultsinlesserosion.Amodelisrecommendedasanartificialharborontheoceancoast,whichisanexcavatedportsurroundedbyamole,connectedwiththeoceanbyanaccesschannelandwiththeshorebyabridge-shapedpier.

简介：Excavatingsandsandgravelonlandincombinationwithconstructingreservoirsforstoringfreshwaterisanidealapproachinatolls.Appropriateminingofgravelfromtheprogradinggravelbeachisacceptable.Diggingreefrockclosetotheedgeofthewideoceanreefflatwithoutsurfaceloosesedimentsonitorsandbeachcanbeaccepted.Excavatingsandfromsomedepthsinlagoonisascientificapproachparticularlyimportantforurbanizedatolls.However,selectingappropriatesitesforminingsandotherthanatsomedepthsinlagoonissuitabletoruralislandswithoutdensepopulations.Thesesitesincludeupdriftsideoflonggroinonthereeffiat,partlyfilledaccesschannel-port,outletofartificialchannelandlagoonmarginontheprogradingcoast.

简介：