基于NPP-VIIRS夜间灯光数据的山西省GDP空间化模拟

选取山西省为研究对象，以美国国家极轨合作仪件-可见红外成像辐射计套件（NPP-VIIRS）夜间灯光数据、GDP统计数据等为数据源，构建GDP空间化拟合模型，建立山西省GDP密度图，据此研究山西省经济的空间差异性。通过对NPP-VIIRS夜间灯光数据的空间化处理，提取灯光指数，并将其与GDP进行回归拟合，建立最佳回归模型，得到GDP密度拟合图；利用县级GDP数据进行线性纠正，从而提高GDP的模拟精度。结果表明：（1）NPP-VIIRS夜间灯光数据与GDP的相关性较高，可用于山西省GDP模拟；（2）与GDP分区建模相比，GDP整体建模的精度更高；（3）山西省GDP的空间分布整体呈由城市中心逐渐向周边辐射的特点，构成GDP过渡带。     

铟镓共掺杂对n-ZnO纳米棒/p-GaN异质结生长行为和光电性能的影响

利用低温水热法在p-GaN薄膜上生长了铟(In)和镓(Ga)共掺杂的ZnO纳米棒。X射线衍射(XRD)、X射线光电子能谱(XPS)和X射线能量色谱仪(EDS)结果表明,In和Ga已固溶到ZnO晶格中。扫描电子显微镜(SEM)结果表明, ZnO纳米棒具有良好的c轴取向性,随着In和Ga共掺杂浓度的增加,纳米棒的直径减小,密度增加。XRD结果表明,In和Ga共掺杂引起ZnO晶格常数增大,导致(002)衍射峰向低角度方向偏移。同时,ZnO的光学性质受到In和Ga共掺杂的影响。与纯ZnO相比, 共掺杂ZnO纳米棒的紫外发射峰都出现轻微红移,这是表面共振和带隙重整效应综合作用的结果。I-V特性曲线表明,随着In和Ga共掺杂浓度的增加,n-ZnO纳米棒/p-GaN异质结具有更好的导电性。     

Dispersive shock waves in three dimensional Benjamin–Ono equation

Dispersive shock waves (DSWs) in the three dimensional Benjamin–Ono (3DBO) equation are studied with step-like initial condition along a paraboloid front. By using a similarity reduction, the problem of studying DSWs in three space one time (3+1) dimensions reduces to finding DSW solution of a (1+1) dimensional equation. By using a special ansatz, the 3DBO equation exactly reduces to the spherical Benjamin–Ono (sBO) equation. Whitham modulation equations are derived which describes DSW evolution in the sBO equation by using a perturbation method. These equations are written in terms of appropriate Riemann type variables to obtain the sBO-Whitham system. DSW solution which is obtained from the numerical solutions of the Whitham system and the direct numerical solution of the sBO equation are compared. In this comparison, a good agreement is found between these solutions. Also, some physical qualitative results about DSWs in sBO equation are presented. It is concluded that DSW solutions in the reduced sBO equation provide some information about DSW behavior along the paraboloid fronts in the 3DBO equation.     

胆碱氧化酶功能化室温磷光量子点的制备及其对氯化胆碱的定量检测

环境友好型纳米生物传感器能够提高传统生物分子传感器的检测性能，在实际应用中具有重要的应用价值。本研究以胆碱氧化酶（ChOx）为模板，在室温（25 ℃）下通过矿化作用制备了一种ChOx功能化的室温磷光（RTP）量子点（QDs）（ChOx RTP QDs）纳米生物传感器，并利用ChOx与氯化胆碱的特异性酶-底物反应和光诱导的电子转移（PIET）实现了对氯化胆碱（Cho）的RTP定量检测。该纳米生物传感器对氯化胆碱检测的线性范围为0.05~20 mmol/L，检出限为0.02 mmol/L。该方法基于QDs的RTP性质，可以有效地避免生物样品背景荧光的干扰，且无需复杂的样品前处理过程，因此该方法较适合于生物样品中氯化胆碱的定量检测。     

基于铜金属有机配合物的热活化延迟荧光材料

具有热活化延迟荧光(thermally activated delayed fluorescence, TADF)特性的配合物可以同时利用单重态和三重态激子,因此发光量子效率较高,近年来受到广大科研工作者的关注。特别是铜金属有机配合物,最低单重态和最低三重态的能量差较小,又可以通过不同配体或取代基进行调节,所以具有较好TADF性能。本文根据配位原子的类型,汇总和分析了近5年具有TADF性质的铜配合物的结构特点和发光性能,并简要讨论了其在有机发光二极管(organic light-emitting diodes,OLEDs)中的潜在应用。     

硫鸟嘌呤修饰的Mn:ZnS QDs磷光探针检测铂(Ⅲ)

通过水相合成法制备了硫鸟嘌呤(TG)修饰的锰掺杂硫化锌量子点(TG-Mn:ZnS QDs)。加入Pt⁴⁺后,Pt⁴⁺会与硫鸟嘌呤上的氮原子结合形成N-Pt⁴⁺配位结构附着在TG-Mn:ZnS QDs的表面,随着Pt⁴⁺浓度的增加,TG-Mn:ZnS QDs-Pt⁴⁺体系发生电子转移而导致磷光逐渐被猝灭,基于此构建了检测Pt⁴⁺的磷光探针。实验中考察了p H、时间对Pt⁴⁺猝灭TG-Mn:ZnS QDs磷光强度的影响。在最佳实验条件下,Pt⁴⁺浓度在0.06~2.4μg/mL范围内与TG-Mn:ZnS QDs的磷光强度呈良好的线性关系y=0.0884x+0.2319,R²=0.991,方法检出限(3σ/n)为1.3μg/mL。该磷光探针适用于实际样品中Pt⁴⁺含量的测定。     

Determination of tyrosine using <Emphasis Type="Italic">p</Emphasis>-sulfonated calix[<Emphasis Type="Italic">n</Emphasis>]arene modified electrode

Cyclic voltammetry was used to detect p-sulfonated calix[n]arenas (SCnA) how to immobilize on gold surface. P-sulfonated calix[n]arenes not only increased the specific surface area of the modified electrode, but also improved the enrichment ability of tyrosine. This led to a significant increase in peak current, and improved the sensitivity of tyrosine determination on the p-sulfonated calix[n]arenes-modified electrode. The modified electrode showed good catalytic ability of l-tyrosine oxidation reaction. The peak current of l-tyrosine increased and the oxidation peak potential shifted negatively with cavity size of the SCnA-modified electrode, which indicated that the catalytic ability of the modified electrode to l-tyrosine oxidation reaction was also enhanced. For the tyrosine guest molecule, the order of electrochemical activity and magnitude of catalytic ability of the oxidation reaction of the three modified gold electrodes was as follows: SC4A?>?SC6A?>?SC8A. The electrode had high selectivity and stability for the determination of tyrosine, with a wide linear range, low detection limit and high sensitivity at different concentrations under different pH values. This resulted in an accurate, fast, sensitive electrochemical method for the determination of tyrosine. The sensor was used for the determination of tyrosine in human urine with satisfactory results.     

Graphene-modified Monolithic Capillary Column for the Microextraction of Trace Benzodiazepines in Biological Samples

A graphene monolithic column was fabricated in a capillary using π-electron-rich poly(N-vinylcarbazole-divinylbenzene) as the supporter through in situ one-step polymerization for the enrichment of trace benzodiazepines in biological samples. This new three-dimensional monolith showed uniformity and a continuous column bed; more importantly, it retained the unique properties of graphene that are typically associated with individual graphene sheets. Based on the large delocalized π-electron system, graphene forms π–π stacking interactions with benzodiazepines and benzene rings of poly(N-vinylcarbazole-divinylbenzene), which not only enhance the extraction performance for benzodiazepines compared to the neat polymer but also provide chemical stability of the graphene monolith. Moreover, several factors likely to affect the extraction, including ionic strength, sample pH, sample volume, and eluant volume were studied in detail. The optimized method gave a linear range of 0.005–1?ng?mL^?1, and detection limits of 1.12–2.35?ng?L^?1. Finally, the graphene monolith was successfully applied to the separation and enrichment of benzodiazepines from urine and hair samples coupled with high-performance liquid chromatography–mass spectrometry. The recoveries were in the range of 78.6–85.6% for urine and 87.2–94.3% for hair with relative standard deviations of 3.4–6.9 and 2.9–8.3%, respectively.     

Trends in Geometric,Energetic, Electronic,and Magnetic Properties of Vanadium–Copper Clusters Cu<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>V with <Emphasis Type="Italic">n</Emphasis> = 1–12: Density Functional Calculations

A systematic quantum chemical investigation on the geometric, energetic, electronic and magnetic properties of vanadium-copper nanoalloy clusters (n = 1–12) is performed by using BPW91/LanL2DZ calculations. The calculated results show that the structural evolution of Cu _n V clusters favors a compact and icosahedral growth pattern and V atom favors occupying the most highly coordinated position. Energetic properties show that doping of one V atom contributes to strengthening the stability of the copper clusters with the growth of the clusters. The stacking mode of clusters apparently has a more important effect on the clusters stability than the electronic structure. However, electronic structures have some contribution to the stability of Cu _n V clusters as well. The electronic properties of Cu _n V are analyzed through vertical ionization potential (VIP), vertical electron affinity (VEA) and chemical hardness (η). The magnetism calculations show that when doping V atom in copper clusters, the cluster system generate a very large magnetic moment and its contribution mainly comes from the 3d orbital of doping-V atom.