SrMoO4:Sm3+,Na+红色荧光粉的形貌调控和发光性能

以Sm³⁺为激活剂,Na⁺为电荷补偿剂,柠檬酸为配位剂,乙二醇作为辅助配位剂,采用溶胶-凝胶法合成前驱体,然后在800℃下焙烧,成功制备了一系列SrMoO₄：Sm³⁺,Na⁺红色荧光粉。用X射线衍射仪、扫描电镜、荧光光谱和傅里叶变换红外光谱等手段对样品的物相、形貌、组成、发光性能和量子效率等进行测试和表征。分析结果表明：制备的SrMoO₄：Sm³⁺,Na⁺荧光粉均为四方晶系结构,掺杂离子的加入对基质晶体结构影响不大。在403 nm近紫外光激发下,产物有4个发射峰,分别位于563、600、647和707 nm处,归属于⁵G_5/2→⁶H_J（J=5/2,7/2,9/2,11/2）的电子跃迁,其中位于647 nm处的主发射峰的相对发光强度最大。当Sm³⁺的掺杂物质的量分数为1%~3%时,发光强度最好,当浓度超过1%~3%时,会发生荧光猝灭。对实验数据进行分析,确定荧光猝灭机理是由于钐离子间交换作用引起的,并计算了能量传递的临界距离为1.77~2.56 nm。此外,还详细研究了乙二醇对SrMoO₄：Sm³⁺,Na⁺荧光粉形貌的影响,研究结果表明：乙二醇加入量为5 mL时,产物形貌均匀,呈球形或椭球形;且分散性较好;荧光强度最大。     

钼酸铵热分解过程动力学研究

有关多相钥酸钦在加热过程中的热分解行为，我们已用热重、差热及高温X一射线衍射等测试方法进行了系统研究以．如物相！fi．rsro为例4．50％（质量分数，下同）（NH4kM070。。·4H。0＋44．85％（NH小M05017＋50．65％（（NH4）2M04013十几（NH4）2M04013）的用酸按混合物消记     

钼酸铋纳米片的制备以及光催化性能测试*

以硝酸铋与磷钼酸为原料,通过水热反应制备高催化活性光催化剂,应用X射线衍射和扫描电子显微镜进行材料表征,通过以氙灯为光源研究材料对四环素的表面光催化降解的特性。本实验涉及无机纳米材料的水热合成、结构表征以及有机类污染物光催化降解应用,将无机化学、物理化学、有机化学和分析化学的理论内容、实验方法与科学研究前沿相结合,能够全方位提升本科大学生的综合实验技能及科学研究水平。     

渣油悬浮床加氢水溶性催化剂预硫化研究 Ⅱ 钼酸盐硫化产物的XPS分析

通过XPS分析法对钼酸盐的硫化行为进行了考察,分别考察了四价钼物种质量分数和硫钼元素的质量分数比，发现硫化产物的表面化学组成中四价钼质量分数和硫钼元素质量分数比不成正比，证实了该产物表面钼的硫化物不完全以MoS2形式存在。未经过临氢加热的硫化产物表面的四价钼物种的质量分数显著低于经过临氢加热的样品的质量分数，说明临氢加热在钼酸盐的硫化过程中起了重要作用。氯化铵是钼酸盐硫化过程中有效的助硫化剂，当它的用量增大时，硫化产物表面四价钼的质量分数也增大。以蒽为探针，使用化学探针法测定了硫化产物在渣油加氢过程中的催化活性，发现随着氯化铵用量的增加，产物的催化活性也相应提高，印证了XPS测定结果。     

某些同多酸根与蛋白质相互作用的共振瑞利散射光谱研究

在酸性介质中,钼酸根、钨酸根和偏钒酸根等同多酸根与牛血清白蛋白（BSA）和人血清白蛋白（HSA）等蛋白质反应形成结合产物时,会导致溶液的共振瑞利散射（RRS）急剧增强,最大散射峰均位于470nm。反应的适宜酸度分别为pH0．9～1．3（钼酸根．BSA体系）,pH1．1—1．4（钨酸根-BSA体系）和pH0．6—0．9（偏钒酸根-BSA体系）。在一定的浓度范围内,不同的反应体系RRS强度与蛋白质浓度成正比,均可用于蛋白质的测定。反应具有很高的灵敏度,不同的同多酸对BSA的检出限（30σ／s）介于4．1—30．5μg/L之间,其中钼酸根体系的灵敏度最高。考察了共存物质的影响并研究了方法的分析应用。     

Synthesis and Structure of One Novel Polyoxometalate Compound Connected via Cerium(Ⅲ) Cation with Three-dimensional Framework H2{[K(H2O)2]2[Ce(H2O)5]2(H2Mo1.16W10.84O42)}·8H2O

One novel polyoxometalate compound connected via trivalent cerium cation as bridge H2{[K(H2O)2]2[Ce(H2O)5]2(H2Mo1.16W10.84O42)}·8H2O 1 was designed and synthesized in aqueous solution. X-ray diffraction analysis reveals that the structure of 1 is a three-dimensional framework assembled from the arrangement of H2Mo1.16W10.84O42 (named paradodecmetalate-B) and Ce(H2O)53 containing two planes, which are constructed through the unification of H2Mo1.16W10.84O4210- and Ce(H2O)53 along the [100] and [001] directions. Crystal data: H96Ce4K4Mo2.32O128W21.68, Mr = 7074.89, monoclinic, P21/n, a = 12.5037(17), b = 17.002(2), c = 12.7473(17) (A), β = 105.966(2)°, V = 2605.4(6) (A)3, Z = 1, Dc = 4.509 g/cm3, F(000) = 3132, μ = 26.098 mm(1, R = 0.0377 and wR = 0.0789 (I ＞ 2σ(I)).     

Na_2MoO_4催化H_2O_2氧化芥子气模拟剂苯甲硫醚的动力学与产物

以苯甲硫醚(Ph SMe)为化学毒剂芥子气的模拟剂,研究了Na2Mo O4催化H2O2溶液氧化Ph SMe的两阶段反应动力学及产物分布.Ph SMe在Na2Mo O4催化H2O2溶液中生成了苯甲亚砜(Ph S(O)Me)和苯甲砜(Ph S(O)2Me).相对无催化H2O2溶液,Na2Mo O4催化在加快Ph SMe氧化为Ph S(O)Me的同时,也将过度氧化产物Ph S(O)2Me的产率提高了两个数量级.95Mo NMR测试表明,Mo O42-与H2O2反应生成了钼酸盐过氧配合物Mo Ox(OO)(4-x)2-,当H2O2/Mo O42-5时,Mo(O2)42-是主要的活性物种,通过直接氧转移方式导致硫醚→亚砜→砜的氧化.     

Studies on hydrothermal synthesis of photolumniscent rare earth (Eu3+ & Tb3+) doped NG@FeMoO4 for enhanced visible light photodegradation of methylene blue dye

FeMoO₄ nanorods and their rare earth (Eu³⁺ and Tb³⁺) doped composites with nitrogen doped graphene (NG) were synthesized by facile hydrothermal method in aqueous medium. X-ray diffraction (XRD) analysis of the as-synthesized samples was done to study the phase purity and crystalline nature. FTIR and Raman Spectroscopy have been studied for investigating the bonding in nanostructures. The surface morphology of the samples was investigated with field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The photolumniscent nature of the samples was investigated by the using the fluorescence spectrophotometer. The photocatalytic degradation efficiency of the prepared pure FeMoO₄ and its rare earth doped composites with nitrogen doped graphene was evaluated as function of visible light irradiation versus concentration of methylene blue (MB dye). The prepared nanocomposites show enhanced photocatalytic efficiency as compared to the bare FeMoO₄ nanorods.     

Thermal Decomposition of Hafnium Phosphate and Related Materials

The thermal decomposition of hafnium phosphate (both in amorphous and crystalline forms), molybdate and tungstate was investigated. Hafnium phosphate has a layered structure, that of molybdate and of tungstate are tetragonal one. On investigating these materials two main endothermic processes with mass loss were observed in the temperature range of 298–1023 K. These processes were identified as crystal and structural water loss of the materials. The total mass loss of hafnium phosphate, molybdate and tungstate was 11,35 and 6.0%, respectively. In the case of mixed hafnium-titanium salts various crystal water quantities were found, depending on the titanium content of the sample. This revised version was published online in July 2006 with corrections to the Cover Date.     

SrMoO4:Er3+-Yb3+ upconverting phosphor for photonic and forensic applications

The Er³⁺-Yb³⁺ codoped strontium molybdate (SrMoO₄) phosphors have been synthesized via chemical co-precipitation method by adding ammonium hydroxide as a base reagent. The phase, crystal structure and formation of spindle-like particles present in the prepared phosphors have been recognized by using the X-ray powder diffraction (XRPD) and Field emission scanning electron microscopy (FE-SEM) techniques. The Fourier transform infrared (FTIR) spectroscopy of the developed phosphors has been analyzed to mark the different functional groups present in synthesized phosphors. The multicolour upconversion emissions observed upon excitation with 980 nm and 808 nm laser diode have been explained on the basis of dopants ions concentration, pump power dependence, energy level structure and decay curve analysis. The colour co-ordinate study confirmed that the codoped phosphor emits non-tunable green colour when excited with the 980 nm laser diode, whereas it shows the colour tunability from yellow to green region upon excitation with the 808 nm laser diode. The applicability of non-tunable green colour emission has been demonstrated in the security ink and latent finger print detection. This shows the utility of the developed phosphors in the photonic and forensic applications.