简介:4-(Succinimido)-1-butanesulfonicacidasanefficientandreusableBronstedacidcatalyzedthesynthesisofpyrano[4,3-b]pyranderivativesundersolvent-freeconditions.Thecatalystcanbepreparedbymixingsuccinimideand1,4-butanesultonethatismoresimpleandsaferthanthepreparationofsuccinimidesulfonicacid.Thismethodhastheadvantagesofhighyield,cleanreaction,simplemethodologyandshortreactiontime.Thecatalystcouldberecycledwithoutsignificantlossofactivity.
简介:摘要现阶段,我国的通信技术迅猛发展,为了更好地满足广大移动通信用户的需求,第四代(4G)移动通信技术应运而生,但是随着应用越来越广泛,4G技术也面临更多的挑战,当然,也有更广大的发展前景。本文主要就移动通信4G关键技术做了简单的分析。
简介:Alowpoweratmosphericpressureplasmajetdrivenbya24kHzACpowersourceandoperatedwithaCH4/airgasmixturehasbeeninvestigatedbyopticalemissionspectrometer.Theplasmaparametersincludingtheelectronexcitationtemperature,vibrationaltemperatureandrotationaltemperatureoftheplasmajetatdifferentdischargepowersarediagnosedbasedontheassumptionthatthekineticenergyofthespeciesobeystheBoltzmanndistribution.TheelectrondensityatdifferentpowerisalsoinvestigatedbyHβStarkbroadening.Theresultsshowthattheplasmasourceworksundernon-equilibriumconditions.Itisalsofoundthatthevibrationaltemperatureandrotationaltemperatureincreasewithdischargepower,whereastheelectronexcitationtemperatureseemstohaveadownwardtrend.Theelectrondensityincreasesfrom0.8×1021m-3to1.1×1021m-3whenthedischargepowerincreasesfrom53Wto94W.
简介:摘要总结了4例CIK细胞免疫治疗肺部肿瘤患者的护理经验,包括治疗前的护理、回输的护理、回输后的并发症护理。认为在CIK细胞治疗护理过程中严格执行规范的护理操作流程,能有效地降低护理安全隐患,保证治疗的效果,提高患者的生活质量。
简介:WithFebruarywelluponus,itseemsthatthoseNewYear’sdietsarefailingfast.随着二月份的到来,不少人新年时制定的合理膳食计划似乎很快被抛之脑后。AnewsurveyhasrevealedthathalfofBritonshavealreadyditchedthediettheystartedJanuaryandit’safternoonsnackingthat’stoblame.一项新的调查表明,一半的英国人没有延续一月份的饮食规律,这都是下午的零食惹得祸。