简介:摘要目的探讨131-I治疗GD伴颈部血管杂音的最佳治疗剂量。方法对57例GD伴颈部血管杂音患者行不同131-I剂量治疗,并进行治疗后2年回顾、观察、统计、分析。结果28例颈部血管杂音伴GD,采用经典剂量,即每克甲状腺组织给予2.96-4.44MBq(以下用实验组80-120uCi/g表示),治疗效果较差,29例颈部血管杂音伴GD采用5.92MBq-7.4MBq(以下用对照组160-200uCi/g表示)治疗效果较好。对照组甲低发生率略高于实验组,但无统计学意义。结论颈部血管杂音伴GD患者采用160-200uCi/g治疗效果好,不仅有助于高代谢症状及体征的迅速控制,而且可提高治愈率,减轻患者经济负担。
简介:Mg-12Gd-2Er-1Zn-0.6Zr(wt%)合金的机械性质上的homogenization和等温的老化处理的效果被调查。猛抛的长时期的叠顺序(LPSO)结构和调节合金的变老的降水顺序分别地被观察并且分析。结果显示14H-LPSO结构在等温的老化过程以后发生在homogenization处理和阶段形式以后。这二个独立过程能被降水温度范围控制。在homogenization处理以后的当演员组合金的延伸的重要增加被归因于粗糙的主要Mg5(Gd,的消失嗯,Zn)阶段和14H-LPSO结构的存在。调查合金的降水顺序是-Mg(SSS)/(D019)/(cbco)/。而且,张力的力量(YTS)和最终的张力的力量(UTS)等温的老化合金珍视的收益有大改进,它能被归因于猛抛的阶段的高密度。图形的AbstractWith延长的变老的时间,阶段在合金被猛抛。14H-LPSO结构和阶段在498K为84h在老化以后在合金共存。14H-LPSO的层结构显然被观察[11\(\overline{2}\)0]Mg方向,它在高分辨率的传播电子显微镜学(HRTEM)被显示出图象。14H类型结构与c的一个时期显示一份叠的订单?=?3.67?nm,它不在等温的老化过程期间变化。
简介:研究定向凝固条件下凝固参数(生长速率v和温度梯度G)对Mg-2.35Gd合金显微组织及室温力学性能的影响。采用金属液淬技术,在温度梯度G为20、25、30K/mm,生长速率v为10-200μm/s条件下通过高梯度Bridgman定向凝固炉制备试样。研究表明,实验合金的显微组织均为胞晶组织,胞晶间距λ随温度梯度和生长速率的增大而减小,其非线性拟合关系分别为λ=136.216v^-0.2440(G=30K/mm)、λ=626.5630G^-0.5625(v=10μm/s),均与Trivedi模型较吻合。随温度梯度和生长速率的增大,合金室温抗拉强度逐渐提高,伸长率逐渐降低。同时,合金室温抗拉强度高于相同冷却速率条件下自由凝固试样的室温抗拉强度。
简介:Theglass-formingability(GFA)andmagneticpropertiesoftheGd_(50)Coso-basedamorphousaiioywithAladditionsubstitutionforCoareinvestigated.ItisfoundthattheGFAandmagneto-caloriceffectoftheGd_(50)Co_(45)Al_5amorphousaiioyarebetterthanGd_(50)Co_(50)amorphousalloy.Themaximummagneticentropychange(-△S_m~(peak))andthemagneticrefrigerantcapacityoftheamorphousalloyunderafieldof5Tareabout6.64J·kg~(-1)K~(-1)and764J·kg~(-1),respectively.Thefielddependenceofmagneticentropychangemeetstheonepredictedbythemeanfieldtheory,whichisinvestigatedforabetterunderstandingofthemagneto-caloricbehaviorsoftheGd_(50)Co_(45)Al_5amorphousalloy.
简介:YPO_4phosphorssingle-dopedwithSb~(3+)orGd~(3+)andco-dopedwithSb~(3+)andGd~(3+)werepreparedbyasolid-statereactionmethod.Thephasepurity,morphology,photoluminescenceexcitationandemissionpropertiesofthepreparedphosphorswereinvestigated.TheresultsshowedthatSb~(3+)couldsensitizeGd~(3+)intheco-dopedphosphorswhichmadethephosphorsexcitablebyshort-waveultraviolet(UV)atawavelengthbetween220and260nm.Under253.7nmexcitation,theco-dopedphosphorsY_(1–x–y)PO_4:Sb~(3+)x,Gd~(3+)yshowedstrongemissionofGd~(3+)atawavelengthof312nmwhoseintensitychangedwiththedopingconcentrationsofGd~(3+)andSb~(3+).TheoptimizedY_(0.77)PO_4:Sb~(3+)0.07,Gd~(3+)0.16phosphorshowedanintensitycomparabletocommercialLaPO_4:Cephosphor(UVB-315),makingitapotentialcandidateformercurylow-pressuredischargenarrow-bandUV-Bemittinglamps.
简介:Themicrostructuresofas-castandas-solutionMg–12Gd–2Er–1Zn–0.6Zralloyswereinvestigatedbyopticalmicroscopy(OM),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),highresolutiontransmissionelectronmicroscopy(HRTEM)X-raydiffraction(XRD)andselected-areaelectrondiffraction(SAED)inthepresentinvestigation.TheresultsshowthattheprimaryeutecticphaseMg5(Gd,Er,Zn)andsomeflocculentfeaturesarefoundintheas-castalloy;theSAEDpatternindicatesthattheseflocculentfeaturesarethedenseareasofstackingfaults.The14H-LPSOstructureprecipitatesinthetemperaturerangeof673–793K,andthevolumefractionof14H-LPSOstructureincreaseswiththeextensionofheatingtime;however,thereisnoprecipitationof14H-LPSOstructurewhenthetemperaturereachesupto803K.Inaddition,theMg5(Gd,Er,Zn)phasedissolvesgraduallyalongwiththeprecipitationof14H-LPSOstructure.