聚丙烯酸功能化LaF_3:Ce~(3+)/Tb~(3+)荧光探针测定鲑鱼精DNA

用溶剂热法,160℃条件下,反应12 h,成功制备了La F3:Ce3+/Tb3+晶体(PDF 72-1435)。用XRD对材料进行了表征。并用聚丙烯酸(PAA)对材料进行了功能化,红外吸收光谱显示材料表面成功修饰上羧基(─COOH)。以COOH-La F3:Ce3+/Tb3+材料为荧光探针,基于DNA对材料的发光淬灭,实现了对DNA的定量测定。在p H=5.5条件下,功能化荧光材料的荧光强度和鲑鱼精DNA(hs-DNA)的浓度(0.60~25.0μg/m L)呈线性关系,线性方程为ΔF=113.9-1.5c,检测限为0.97μg/m L,相关系数R=0.998 2,RSD为0.97%。     

基于荧光共振能量转移功能化LaF_3:Ce~(3+)/Tb~(3+)晶体测定水样中汞(Ⅱ)

在乙醇和乙二醇混合溶剂中,180℃条件下,反应12h,用溶剂热法,成功制备了LaF3:Ce3+/Tb3+晶体(PDF 72-1435)。用X射线衍射仪对材料进行了表征。并用聚丙烯酸(PAA)对LaF3:Ce3+/Tb3+进行了功能化,红外吸收光谱显示LaF3:Ce3+/Tb3+表面成功修饰羧基(—COOH)。COOH—LaF3:Ce3+/Tb3+功能化材料为供体,汞离子(Ⅱ)为受体,研究了体系的荧光共振能量转移(FRET)。在最佳条件下,功能化荧光材料的荧光强度和汞离子(Ⅱ)的浓度(0.20~10.0μg/mL)呈线性关系,线性方程为ΔF=98.451-3.003c,检测限为0.035μg/mL,相关系数R=0.998 9,相对标准偏差(RSD)为4.8%(n=7)。并成功用于水样中汞的测定。     

水热合成NaYF_4:Tb~(3+)/Ce~(3+)或Bi~(3+)体系中Ce~(3+)和Bi~(3+)对Tb~(3+)离子发光的增强作用

利用水热法合成六方相NaYF4:Tb3+/Ce3+或Bi3+体系,用X射线粉末衍射仪以及荧光分光光度计对所合成样品的物相结构以及荧光性能进行表征。在紫外光激发下,Ce3+能有效吸收紫外光并传递给Tb3+离子,Tb3+离子的绿色发光得到增强,Bi3+离子对Tb3+离子的荧光性能也有一定的敏化作用。水热合成NaYF4:Tb3+/Ce3+或Bi3+体系中Ce3+和Bi3+对Tb3+离子的荧光性能具有增强作用。     

N,N-二甲基癸基氧化胺与鲑鱼精DNA相互作用的研究

通过浊度、紫外吸收和表面张力的测定,研究了N,N-二甲基癸基氧化胺(C10DAO)与鲑鱼精DNA的相互作用。结果表明:中性条件时C10DAO不能诱导DNA发生相分离;C10DAO浓度高于6.0 mmol/L的C10DAO-DNA体系达到临界pH时,静电相互作用导致体系浊度发生跃变;C10DAO浓度为6.0~16.0 mmol/L时,对应的临界pH改变显著。紫外吸收和表面张力结果也证实了相互作用的存在;荧光猝灭表明低质子化度的C10DAO可诱导DNA构象发生转变。     

Eu~(3+)掺杂浓度对NaYF_4:Eu~(3+)晶体荧光强度的影响

在乙醇和乙二醇的混合溶剂中,用溶剂热法,150℃,反应12 h,成功合成了NaYF4:Eu3+晶体。室温下,用X射线衍射对材料的组成进行了表征,JCPDS号为16-0334。荧光光谱分析表明,在395 nm(7F0→5L4)紫外光激发下,其发射峰在476 nm、540~578 nm、718 nm分别对应着Eu3+的5DJ(J=0,1,2,3)→7FJ(J=1,2,3,4)能级跃迁。并讨论了离子Y3+:Eu3+不同浓度掺杂比对荧光性质的影响。结果表明,Eu3+的最佳掺杂浓度比为5%,当掺杂浓度为10%时,出现荧光猝灭。     

超声波辅助合成YOF:Tb~(3+)荧光粉及其荧光性能

以Tb4O7与Y2O3为主要原料,用超声波辅助合成前驱体,经高温煅烧后合成了稀土YOF:Tb3+绿色荧光粉。采用XRD、SEM和荧光分光光度计对样品的结构、形貌和荧光性能进行分析。样品XRD表明,产物为四方晶系YOF:Tb3+,结晶度较好。SEM表明合成的荧光粉为100mm~200nm左右的纳米颗粒。荧光分析显示,荧光粉的荧光性能受前驱体辅助合成方式及Tb3+掺杂浓度等各种因素影响。在230nm的紫外光激发下,40℃的低温超声波辅助下合成的前驱体经过煅烧后制得的荧光粉荧光性效果好。当Tb3+的摩尔掺杂浓度大于5%时,出现浓度淬灭现象。     

铕离子(Ⅲ)荧光探针法测定阿莫西林的含量

建立铕离子(Ⅲ)荧光探针法测定阿莫西林含量的实验方法。在激发波长为269nm和发射波长为615nm处,pH值为8.5、静置时间为5min、铕离子浓度为1.864×10~(-4)mol/L条件下,考查阿莫西林浓度对荧光强度的影响。结果表明,在1.651×10~(-5)mol/L～6.606×10~(-5)mol/L范围内,阿莫西林的浓度c与荧光强度F存在线性关系,标准曲线的线性回归方程为F=-4.450c+1268.747,线性相关系数为0.9918,平均回收率为98.93%。     

La_2(MoO_4)_3:Eu~(3+)纳米红色荧光粉的合成及其发光特性

以水合硝酸镧、水合硝酸铕、硬脂酸和水合钼酸钠为反应物,采用溶剂热法合成了Eu~(3+)离子掺杂的La_2(MoO_4)_3:Eu~(3+)纳米红色荧光粉。利用TEM、XRD、FL对其形貌、结构和发光性能进行了表征。考察了溶剂种类、反应时间、反应温度、Eu~(3+)掺杂量对产物微观形貌和发光性能的影响。结果表明:以异丙醇为溶剂、反应温度180℃、反应时间12 h条件下,得到的样品结晶度高、分散性好、形貌均一,粒径小于100 nm。该样品可被近紫外光(波长391.0 nm)和蓝光(波长462.5 nm)有效激发,最大发射波长位于613.5 nm,为窄带的红光。La_2(MoO_4)_3:Eu~(3+)的发光强度与Eu~(3+)离子掺杂量有关,其最佳掺杂摩尔分数xEu~(3+)=0.15{xEu~(3+)=n(Eu~(3+))/[n(Eu~(3+))+n(La~(3+))]}。     

罗丹明B类Cu~(2+)荧光增强型探针的合成及其选择性识别

设计并合成了一种可用于识别的Cu~(2+)新型荧光探针(3',6'-双(二乙氨基)-2-(4-(二乙氨基)-2-羟基苯胺基-螺(异喹啉-1,9'-氧杂蒽)-3-酮)(RB)。通过红外、元素分析、质谱、~1HNMR、~(13)CNMR等手段表征了探针的结构。其光谱性和离子选择性实验结果表明,RB自身荧光很弱,但是与Cu~(2+)结合后会发生显著的荧光增强,而与其他金属离子结合后,荧光强度变化很小。说明RB对Cu~(2+)具有很好的选择性和较高的灵敏度,可用作Cu~(2+)荧光增强型探针,据此建立了一种测定Cu~(2+)的新型分析方法。     

4′-(2-呋喃基)-3,2′:6′,3″-三联吡啶Zn(Ⅱ)配合物的合成、晶体结构与发光性质研究

通过溶剂热法以Zn(CH3COO)2·2H2O,4′-(2-呋喃基)-3,2′:6′,3″-三联吡啶与对苯二甲酸为原料(物质的量比1:1:1),以无水乙醇和H2O为溶剂(体积比1:1),140℃恒温反应,合成标题配合物[Zn(3263ftpy)2(bdc)]·2(H2O)(3263ftpy=4′-(2-呋喃基)-3,2...     

稀土离子(Gd~(3+),Ce~(3+)/Ce~(4+),Eu~(3+))对Tb~(3+)掺杂硅酸盐玻璃发光性能的影响

研究了(Gd3+,Ce3+/Ce4+,Eu3+)对Tb3+掺杂硅酸盐玻璃发光性能的影响.结果表明:Tb3+掺杂硅酸盐玻璃可以发出弱蓝光(400～460 mm)和较强的绿光(480～600mm).Gd3+对Tb3+的发光起敏化作用,可提高TB3+掺杂硅酸盐玻璃的发光强度.在空气中熔制的玻璃中Ce3+和Ce4+同时存在,Ce3+对Tb3+发光起敏化作用;而Ce4+对Tb3+发光起淬灭作用.由于Ce4+比例比较高,CeO2加入导致TB3+发光强度降低,同时也缩短了Tb3+发光余辉.加入Eu2O3时,Eu3+自身发光分散了激发Tb3+发光的能量,使Tb3+的特征发射强度降低.     

水热法制备SrF2:Ce3+,Tb3+荧光粉及其发光性质研究

采用水热法合成了具有立方相结构的Ce3+、Tb3+共掺杂的SrF2发光材料SrF2:Ce3+,Tb3+,利用粉末X-射线衍射( XRD)对其结构进行了表征,并研究了掺杂量、水热反应时间、激发波长对SrF2:Ce3+,Tb3+发光性质的影响.荧光光谱研究结果表明,SrF2:Ce3+,Tb3+在254 nm波长紫外光激发下...     

Ce~(3+):LiYF_4和Ce~(3+):LiLuF_4晶体生长与其紫外光谱特征

采用提拉法在CF4气氛中生长高质量掺Ce3+的LiYF4和LiLuF4晶体.测试了晶体的紫外光谱,并从配位场理论角度解释了Ce3+在2种氟化物晶体中紫外光谱特性的差异.结果表明:Ce3+在LiYF4晶体的吸收谱宽度比在LiLuF4晶体中更宽.Ce3+:LiYF4晶体的吸收峰和荧光峰的位置相对Ce3+:LiLuF4晶体的出现紫移.认为其主要原因是由于在LiYF4晶体中,Ce3+和相邻的F的距离更近,Ce3+的d电子与F之间的相互排斥作用更大.     

A new thermosensitive fluorescent probe for diol sensing: Poly(N-isopropylacrylamide-co-vinylphenylboronic acid)-alizarin red S complex

The reversible complex formation between newly synthesized temperature sensitive copolymer, N-isopropylacrylamide-co-4-vinylphenylboronic acid and diol carrying molecules was first investigated by fluorescence spectroscopy. This investigation resulted in a development of a temperature sensitive-fluorescent probe used for quantitative determination of diol carrying molecules. In the first stage of competitive assay developed in this study, the receptor (i.e. boronic acid groups of temperature sensitive copolymer) and the reporter (a catechol dye, alizarin red S) associated at the selected pH and temperature to give a fluorescent cyclic boronate ester. The stimuli–responsive character of copolymer allowed to control the formation of fluorescent complex by adjusting the temperature. The maximum intensity was observed at 660 nm in the emission spectrum of the cyclic boronate ester. The fluorescent receptor–reporter complex (i.e. cyclic borate ester formed from boronic acid and ARS) was then partly dissociated in the presence of diol carrying guest due to the formation of another non-fluorescent complex between copolymer and guest. Various agents from different material groups, fructose, ascorbic acid, β-nicotinamide adenine dinucleotide (β-NAD) and horse radish peroxidase (HRP) were used as target diol carrying agents. The decrease in fluorescent intensity due to the dissolution of the receptor–reporter complex is proportional to the concentration of target diol carrying agent.     

壳聚糖/聚丙烯酸水凝胶的制备及对Cu~(2+)和Cd~(2+)的吸附

以丙烯酸(AA)和壳聚糖(CS)为原料,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,利用辉光放电电解等离子体(GDEP)技术在水溶液中一步引发制备了壳聚糖/聚丙烯酸(CS/PAA)水凝胶。采用FTIR、XRD和SEM对水凝胶的结构和形貌进行了表征,考察了溶液p H、吸附时间和初始质量浓度对Cu~(2+)和Cd~(2+)吸附的影响,探讨了水凝胶的重复利用性。结果表明:AA成功接枝到了CS链上,形成了具有多孔三维网络结构的CS/PAA水凝胶;该水凝胶对Cu~(2+)和Cd~(2+)的吸附符合准二级动力学模型和Langmuir吸附等温式;在最佳吸附p H下(p H=4.3),吸附120 min,CS/PAA水凝胶对Cu~(2+)和Cd~(2+)的最大实际吸附量分别为151.2和298.8 mg/g;该水凝胶在0.015mol/L乙二胺四乙酸四钠(EDTA-4Na)溶液中吸附解吸4次后,吸附量变化不大,说明CS/PAA水凝胶具有优异的再生和重复利用性。     

Poly(butadiene-acrylic acid(g)acrylonitrile(g)acrylic acid)

Summary In the present work we describe, the synthesis and characterization of a new gel obtained by crosslinking a cooligomer of butadiene-acrylic acid (BuAA), by reaction with acrylonitrile and acrylic acid. The purified product was characterized by FTIR, elemental analyses and scanning electronic microscopy. The thermal properties were studied and swelling indexes were determined in different solvents and at different pH values. The capacity of poly(butadiene-acrylic acid(g)acrylonitrile(g)acrylic acid) [gel A] to separate different organic substances, such as amino acids and colorants, was determined.     

Poly(acrylic acid)-grafted magnetic nanoparticle for conjugation with folic acid

Poly(acrylic acid) (poly(AA))-grafted magnetite nanoparticles (MNPs) prepared via surface-initiated atom transfer radical polymerization (ATRP) of t-butyl acrylate, followed by acid-catalyzed deprotection of t-butyl groups, is herein presented. In addition to serve as both steric and electrostatic stabilizers, poly(AA) grafted on MNP surface also served as a platform for conjugating folic acid, a cancer cell targeting agent. Fourier transform infrared spectroscopy (FTIR) was used to monitor the reaction progress in each step of the syntheses. The particle size was 8 nm in diameter without significant aggregation during the preparation process. Photocorrelation spectroscopy (PCS) indicated that, as increasing pH of the dispersions, their hydrodynamic diameter was decreased and negatively charge surface was obtained. According to thermogravimetric analysis (TGA), up to 14 wt% of folic acid (about 400 molecules of folic acid per particle) was bound to the surface-modified MNPs. This novel nanocomplex is hypothetically viable to efficiently graft other affinity molecules on their surfaces and thus might be suitable for use as an efficient drug delivery vehicle particularly for cancer treatment.     

掺杂Eu3+或Tb3+的(Gd,Lu)2O3粉体的发光性能

采用高温固相法在空气中合成了(Od,Lu)2O3,(Gd,Lu)2O3:Eu3+和(Gd,Lu)2O3:Tb3+系粉体.研究了二元系中Lu2O3的摩尔分数对抑制Gd2O3高温相变、粉体的发光性质和光谱性质的影响.结果表明:在(Gd,Lu)2O3系粉体中,当Lu2O3的摩尔分数(下同)大于40%时,能在煅烧温度不低于1 700℃情况下,抑制Gd2O3的相变得到利于制备透明陶瓷的立方相结构.而且随着Lu3+离子的浓度增加,先后观察到红移和蓝移现象;在(Gd,Lu)203:Eu3+系粉体中,粉体的发光强度随着Lu3+掺杂量增加而减小,Eu3+的最佳掺杂量为7%;在(Gd,Lu)2O3:Tb3+系粉体中,Tb3+离子的最佳掺量为1%.     

Cross-Linked Poly(acrylic acid) Microgels from Precipitation Polymerization

Cross-linked poly(acrylic acid) microgels were prepared via thermally initiated free-radical precipitation polymerization in a binary organic solvent. N,N′-Methylenebisacrylamide (MBA) and 2,2′-azobisisobutyronitrile were used as cross-linker and initiator, respectively. The effect of (MAB) concentration on different features of sample (i.e., spectral characteristics, glass transition temperature, equilibrium swelling, gel content and rheological properties) was investigated. The Flory-Rehner equation and rubber elasticity theory were used to discuss the network structure of polymer. Apparent and rotational viscosities were used to determine the optimal cross-linker concentration. The sample maximum with value of viscosity was obtained using 1.6 mmol/L of the cross-linker. In addition the m and n parameter of Ostwald equation were investigated as well.     

Nd Ce：YAlO3激光晶体中Ce^3＋→Nd^3＋的能量转移特性

测试并分析了Nd,Ce:YAlO_3晶体的吸收光谱、激发光谱和发光光谱,证实了YAlO_3中存在着Ce~(3+)→Nd~(3+)的能量转移,因此掺入Ce有可能大大提高Nd:YAlO_3的激光效率.