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1.
In this article, a facile and environmentally friendly method was applied to fabricate BSA-conjugated amorphous zinc sulfide (ZnS) nanoparticles using bovine serum albumin (BSA) as the matrix. Transmission electron microscopy analysis indicated that the stable and well-dispersed nanoparticles with the diameter of 15.9 ± 2.1 nm were successfully prepared. The energy dispersive X-ray, X-ray powder diffraction, Fourier transform infrared spectrograph, high resolution transmission electron microscope, and selected area electron diffraction measurements showed that the obtained nanoparticles had the amorphous structure and the coordination occurred between zinc sulfide surfaces and BSA in the nanoparticles. In addition, the inhibition effects of BSA-conjugated amorphous zinc sulfide nanoparticles on tumor cells growth were described in detail by cell viability analysis, optical and electron microscopy methods. The results showed that BSA-conjugated amorphous zinc sulfide nanoparticles could inhibit the metabolism and proliferation of human hepatocellular carcinoma cells, and the inhibition was dose dependent. The half maximal inhibitory concentration (IC50) was 0.36 mg/mL. Overall, this study suggested that BSA-conjugated amorphous zinc sulfide nanoparticles had the application potential as cytostatic agents and BSA in the nanoparticles could provide the modifiable site for the nanoparticles to improve their bioactivity or to endow them with the target function.  相似文献   

2.
We have investigated the effect of zinc concentration ([Zn]/[Cu]=0–100 at%) on nanostructural, optical and electrical properties of CuS–ZnS binary thin films grown on glass substrate by the spray pyrolysis technique. X-ray diffraction analysis showed that the films were crystallized with mixed structures of CuS hexagonal and ZnS cubic structure. UV–vis optical measurements analysis showed that these binary films have a relatively high absorption coefficient (~105 cm?1) in the visible spectrum with a direct band gap in the range of 2.57–2.45 eV in agreement with the corresponding room temperature PL spectra. The electrical studies showed that all these samples have a p-type conductivity and the free hole density decreases with increasing [Zn]/[Cu] molar ratio, in agreement with the reflectance spectra of the layers, originating from plasma oscillations.  相似文献   

3.
Quaternary compound semiconductor Cu2ZnSnS4 (CZTS), which appears to be a promising candidate for the absorber of a thin film type solar cell, was grown on polycrystalline Ag substrates by electrochemical epitaxial method. The elements were deposited in the following sequence: S/Sn/S/Cu/S/Zn/S/Cu… , the order being one cycle of SnS, one cycle of ZnS and two cycles of CuS. Morphology of the deposit has been characterized by field emission scanning electron microscopy (FE-SEM) with an energy dispersive X-ray (EDX) analyzer. X-ray diffraction (XRD) studies showed a (112) preferred orientation for the deposit. X-ray photoelectron spectroscopy (XPS) of the deposit indicated an approximate ratio 2:1:1:4 of Cu, Zn, Sn, and S, the expected stoichiometry for the deposit, and similar results have been obtained from EDX data. Near IR absorption measurements of the deposit at room temperature indicated a direct band gap of 1.5 eV, and open-circuit potential (OCP) studies indicated a good p-type property, both of which were suitable for fabricating a thin film solar cell.  相似文献   

4.
酒石酸乙酰异戊酰泰乐菌素(ATLL)是一种新的大环内酯类兽用抗菌药,研究 ATLL与蛋白质的相互作用非常重要,这直接与 ATLL 在体内的药效相关。牛血清白蛋白(BSA )结构上与人血清白蛋白(HSA)同源,因此,常用它作研究药物与蛋白质相互作用的蛋白模型。血液中有许多金属离子,已有关于体内单一离子对药物与蛋白质相互作用影响的研究,采用多光谱方法对ATLL与BSA相互作用及Zn2+和Cu2+的影响进行研究。结果表明,BSA的荧光猝灭属于静态猝灭,Zn2+和Cu2+分别使有效猝灭常数降低和增大。主要的相互作用力为氢键和疏水作用力。ATLL改变蛋白质色氨酸和酪氨酸的微环境极性。紫外光谱分析发现,Cu2+可能是通过Cu2+‐ATLL复合物以金属离子架桥作用来影响ATLL与BSA的作用,Zn2+可能通过与ATLL的竞争作用结合BSA。红外光谱分析表明,ATLL使BSA的β‐折叠和α‐螺旋结构向β‐转角和无规卷曲转变。这些基础数据有助于阐明在生理条件下,有无Zn2+,Cu2+时ATLL与BSA的相互作用机制及金属离子在药物与蛋白质作用过程中对蛋白质功能的影响。  相似文献   

5.
We consider the effect of the order in which In and CuCl impurities are added during thermal doping on the luminescence characteristics of ZnS, and also their role in formation of emission centers in zinc sulfide. We show that the order in which the impurities (acting as activators or coactivators) are added to the ZnS plays the determining role in formation of the spectral characteristics of the luminophore obtained. We have established that adding indium first during thermal doping of zinc sulfide with In and CuCl prevents diffusion of Cu into the interior of the ZnS. Adding indium after CuCl or adding indium simultaneously with CuCl prevents formation of the Cu2S and CuS phases or promotes degradation of the indicated phases in ZnS. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 601–605, September–October, 2006.  相似文献   

6.
A quaternary CuO–CuS–ZnO–ZnS nanocomposite was successfully synthesized via a facile microwave irradiation based on the preprepared ZnS and CuO nanoparticles. CuO–CuS–ZnO–ZnS nanocomposite was a porous photocatalyst, providing excellent adsorption performance. It was sensitive to both ultraviolet and visible light, moreover, the photoelectrochemical measurements confirmed that there was a high separation rate and low recombination rate of photo-generated charge carriers in the nanocomposite, endowing excellent photocatalytic activity in the sunlight. Under the simulated solar light irradiation, the removal efficiency of rhodamine B (RhB) pollutant (30 mg/L) over CuO–CuS–ZnO–ZnS nanocomposite was 33.98 and 2.90 times of pristine CuO and ZnS, respectively. The outstandingt photocatalytic performance was attributed to Z-scheme charge transfer path.  相似文献   

7.
Wen Yu 《Applied Surface Science》2009,255(11):5709-5713
Via a simple aqua-solution hydrothermal route, uniform ZnS nanorod arrays were fabricated upon pulse-plating Zn nanocrystallines. Particularly, low temperature (95 °C) and short time (1 h) were employed in the hydrothermal reaction. ZnS nanorods were found to be grown along certain Zn crystalline direction. Control experiments which were performed by replacing Zn nanocrystallines with Zn plate found no one-dimensional ZnS nanostructure on the substrate. Therefore, it was proposed that pulse-plating Zn nanocrystallines acted as both reactant and seed during the hydrothermal process. ZnS nanorod arrays could be theoretically fabricated on almost any raw base plate as long as Zn nanocrystallines could be pulse-plated on the plate. The ZnS nanorod arrays with high length-to-diameter ratio were expected to be a potential candidate for future field-emission devices.  相似文献   

8.
ZnS nanobelts have been fabricated by ion-exchange reaction using pure Zn powder and CdS nanopowder as starting materials. The morphology and microstructure of ZnS nanobelts were measured by scanning electron microscopy and high-resolution transmission electron microscopy. The results show that the products consist of a large quantity of ZnS nanobelts, and the nanobelts are grown as bunches randomly distributed on the substrate. The root of the bunch shows that the nanobelts are grown from a site. The ZnS nanobelts have a uniform cross-section along their lengths, and typical lengths of several tens to several hundreds of micrometers. Au nanoparticles are located at or close to the tips of the ZnS nanobelts, served as the catalyst for the growth of the vapor-liquid-solid mechanism. In addition, the nanocombs, nanosaws and nanosprings of ZnS are also found in the products.  相似文献   

9.
本文首次报导用ZnxCd1-xSySe1-y四元基质制备黄色ACEL粉末材料.提出了用四元系镧备黄色ACEL材料的设计思想,通过实验,确定了合适的组分x,y值,采用较简便工艺,获得了亮度较高,色度符合使用要求的黄色ACEL粉。测量了此材料在不同使用条件下的发光特性,为应用目标提供了参数。  相似文献   

10.
以3-巯基丙酸(MPA)为稳定剂,采用水相合成法合成了具有优良光学性质的Mn掺杂ZnS量子点。该量子点在室温条件下即可发射较强的磷光信号。将量子点与牛血清蛋白(BSA)偶联后,形成了纳米复合材料。由于BSA对量子点表面缺陷进行了有效修复,量子点发出的磷光明显增强。当加入头孢曲松钠后,头孢曲松钠与BSA的相互作用使量子点的磷光被有效猝灭,该磷光猝灭量(△P)与头孢曲松钠的浓度在一定范围内呈良好的线性关系(R=0.99)。量子点与BSA偶联的最佳条件为:pH=7.4,反应温度37 ℃,反应时间40 min,BSA浓度80 mg·L-1,量子点浓度40 mg·L-1。反应形成新的生物纳米复合材料,作为头孢曲松钠的磷光探针,其线性范围为0~30 μmol·L-1,相关系数R=0.99,检出限为0.14 μmol·L-1,相对标准偏差为1.63%。  相似文献   

11.
Photoluminescence (PL) properties of differently doped nanocrystalline ZnS encapsulated by ZnO (ZnS/ZnO) are reported. It is found that in all cases aluminium as an extra/additional dopant leads to PL enhancement. In comparison to reported blue emitting bulk ZnS:Ag, or green emitting bulk ZnS:Cu, our nanocrystalline samples show a different PL emission profile. This observation is attributed to nanogranule formation, different dopant levels and ZnO capping related energy level modifications.  相似文献   

12.
用荧光分光光度法研究了Zn2+,Mn2+,Cd2+,Na+,K+,Ag+,Cu2+和Pb2+等金属离子修饰的ZnS/PAMAM树形分子纳米复合材料的荧光发射性能。结果表明:不同金属离子修饰效果不同。Zn2+,Mn2+和Cd2+修饰后,ZnS/PAMAM树形分子纳米复合材料的荧光发射强度有不同程度提高;Ag+,Cu2+和Pb2+的修饰对荧光有不同程度的猝灭作用;而Na+和K+的修饰对荧光发射无明显影响。与修饰前相比,Cd2+离子修饰的ZnS/PAMAM树形分子纳米复合材料标记的潜指纹发射的蓝色荧光更加明亮,与背景反差更加明显。这对提高潜指纹的显现精度和准确率有很好的借鉴价值。  相似文献   

13.
A blue-green-conversion of the luminescence of ZnS/Zn and ZnS/S which are annealed at 350 °C can be measured on phosphors with different thermal equilibria (room temperature or 350 °C). The blue-green-conversion of ZnS/S equals this of ZnS/Cu. The conversion depends on the amount of the short wavelength blue emission band in the luminescence of the phosphor. The high energy blue emission band and the blue-green-conversion of the luminescence seem to be coupled to disturbances of the sulphur sublattice.  相似文献   

14.
First-principles calculation is carried out on the interface of the ZnS(001) monolayerand Cu(111) surface. It is found that the ZnS monolayer significantly reconstructs aftergeometry optimization. The out-of-plane S atom has a positive displacement in thez directionwhile other atoms (Zn and S) have small displacements on the ZnS monolayer. The interfacestacking sequence has an influence on the flatness of the ZnS monolayer and the bindingenergy of the interface. There are two approaches for the ZnS monolayer to reach thelowest energy state which take place on the two kinds of S atoms in the ZnS monolayer andresult in the bulging feature. The van der Waals (vdW) interaction exists between ZnSmonolayer and Cu surface.  相似文献   

15.
When conducting EXAFS at the Cu K‐edge for ZnS:Cu with very low Cu concentration (<0.04% Cu), a large background was present that increased with energy. This background arises from a Zn X‐ray Raman peak, which moves through the Cu fluorescence window, plus the tail of the Zn fluorescence peak. This large background distorts the EXAFS and must be removed separately before reducing the data. A simple means to remove this background is described.  相似文献   

16.
运用荧光光谱(FS)及紫外光谱(UV)研究了有/无金属离子Cu2 或Zn2 参与时中药有效成分伞形花内酯与生物大分子牛血清白蛋白(BSA)的相互作用。实验结果表明:有/无金属离子参与时,伞形花内酯均与BSA形成基态复合物从而猝灭BSA的内源性荧光,猝灭原因主要为静态猝灭和非辐射能量转移;金属离子参与使得KA增大,n仍维持在2左右;伞形花内酯分子能够扦插入BSA分子内部,温度以及金属离子参与对伞形花内酯与BSA分子中荧光性氨基酸残基间的空间距离r影响不大。有/无金属离子参与时伞形花内酯与BSA的作用过程均是一个熵增加和Gibbs自由能降低的自发超分子作用过程。伞形花内酯与BSA之间以静电相互作用为主,金属离子参与使伞形花内酯与BSA分子间静电相互作用增强,故ΔH对ΔG的贡献增大。  相似文献   

17.
田昕  曹立新  柳伟  苏革  董博华 《发光学报》2012,33(7):736-741
本文采用水相合成方法制备了ZnS∶Cu量子点并进行了ZnS壳层修饰,研究了壳层厚度对ZnS∶Cu量子点光学性质的影响,采用TEM、XRD、PL、PLE和UV-Vis等测试方法对其进行了表征。实验结果表明,合成的ZnS∶Cu/ZnS量子点为立方闪锌矿,尺寸分布均匀呈球形,分散性良好,经过壳层修饰平均粒径由2 nm增加到3.2 nm。随着ZnS壳与ZnS核量的比的增加,量子点的PLE激发峰位置和UV-Vis吸收谱线出现红移,也说明了量子点的尺寸增大,证明ZnS在ZnS∶Cu量子点的表面生长,形成了核壳结构的ZnS∶Cu/ZnS量子点。随着壳层增厚,量子点与铜离子发光中心相关的发射峰强度先增大后减小,当壳核比ns/nc=2.5时,发光强度达到最大。  相似文献   

18.
A composite Zn/ZnS coating was prepared by a novel compound technology-combining high velocity arc spraying and low temperature ion sulfurizing in this paper. The surface and cross-section morphologies were observed by scanning electron microscopy (SEM). The X-ray diffraction (XRD) pattern for the Zn/ZnS coating implies that it mainly consists of Zn and ZnS. The nanohardness and elastic modulus were measured by a nano-indentation tester. The tribological behaviors were investigated on a ball-on-disk wear tester under dry condition. The results showed that the friction coefficient and worn depth of the composite Zn/ZnS coating were low and stable, indicating that it had excellent friction-reduction and anti-wear properties under dry condition.  相似文献   

19.
以高纯ZnS粉末为基质,采用高温转相、扩散,以及表面涂敷工艺,制得了147Pm激发的ZnS:Cu,Cl发光粉。分析了ZnS:Cu,Cl的晶体结构,测量了ZnS:Cu,Cl的激发光谱、发射光谱、发光亮度。其晶体结构主要是六方纤锌矿型结构,激发光谱峰值波长为341nm,发射光谱峰值波长为513nm,初始发光亮度达到312mcd/m2。由激发光谱的峰值波长341nm推算得到六方ZnS晶体的禁带宽度为3.64eV。分析了147Pm激发的ZnS:Cu,Cl发光粉的发光寿命,其发光寿命达到5年以上。还探讨了该放射性发光粉的发光机理。147Pm激发的ZnS:Cu,Cl的稳定发光,实际上是激发过程与复合过程的准平衡。ZnS:Cu,Cl的绿色发光来源于深施主-深受主对的复合发射。实验结果的分析表明,ZnS:Cu,Cl中深施主-深受主之间的能级间隔约为2.42eV。  相似文献   

20.
3-Mercaptopropionic acid-capped core/shell ZnS:Cu/ZnS and ZnS:Mn/ZnS doped quantum dots (QDs) prepared through hydrothermal methods exhibit high photoluminescence intensity as well as good photostability. These water-dispersible nanoparticles exhibit high fluorescence sensitivity to folic acid due to the high affinity of the carboxylate groups and nitrogen atoms of folic acid towards the Zn surface atoms of the doped dots. Quenching of the fluorescence intensity of the QDs allows the detection of folic acid concentrations as low as 11 μM, thus affording a very sensitive system for the sensing of this biologically active molecule in aqueous solution. The possible quenching mechanism is discussed.  相似文献   

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