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51.
通过改进的热溶剂胶体合成法制备了单分散的Ni12P5纳米粒子,并利用X射线衍射、透射电子显微镜、X射线光电子能谱、X射线能谱对Ni12P5纳米粒子的晶体结构、化学组成和形貌等进行了表征。基于单分散Ni12P5纳米粒子研制出的非酶葡萄糖传感器具有出色的性能,其快速响应时间小于3 s,检测范围广(0.002~4.2 mmol·L-1),灵敏度高达1 572 mA·L·mol-1·cm-2,检测限低至0.8 μmol·L-1。此外,该传感器在用于人体血液中葡萄糖的实际检测中取得了满意的效果。  相似文献   
52.
Zheng  Yuchuan  Wang  ·Shu  Li  Ruifeng  Pan  Le  Li  Liangqing  Qi  Zhaopeng  Li  Changjiang 《Research on Chemical Intermediates》2021,47(6):2421-2431
Research on Chemical Intermediates - Water-soluble fluorescent carbon dots (C-dots) were prepared by a hydrothermal process using guanine as the sole carbon and nitrogen source. The as-prepared...  相似文献   
53.
In this paper, biomimetic synthesis of aragonite superstructures using a low molecular weight organic-hexamethylenetetramine (HMT) as an additive in the presence of CO2 supplied by an ammonium carbonate ((NH4)2CO3) diffusion method at room temperature was studied. The products were characterized by scanning or transmission electron microscopy, Fourier transform infrared (FT-IR) spectroscopy, X-ray powder diffractometry, and selected area electron diffraction. The results showed the aragonite superstructures especially dumbbell-flower-like ones were obtained. The formation process of calcium carbonate (CaCO3) in HMT aqueous solution was investigated, suggesting that the products transformed from calcite to vaterite primarily, and then changed into a mixture of aragonite and calcite with an increase of reaction time. The formation mechanism of CaCO3 in HMT solution was also discussed, revealing that aragonite might be controlled by HMT molecules and NH4+ ions together.  相似文献   
54.
以4,4''-二(1-咪唑基)苯硫醚(BIDPT),4,4''-羧基二苯胺(H2aba),5-氧乙酸间苯二酸(H3OABDC),Zn(NO32·6H2O和Cd(NO32·6H2O为原料,用溶剂热法合成了2个配位聚合物[Zn(BIDPT)(aba)]n1)和[Cd(BIDPT)(HOABDC)]n2)。利用X射线单晶衍射、红外、元素分析、热重分析和X射线粉末衍射对其进行了表征。单晶X射线衍射研究发现配合物1为具有二重穿插的三维dia拓扑网络结构;配合物2为3-连接六边形的hcb二维拓扑结构,再通过氢键堆积作用形成三维超分子结构。12具有很好的荧光性质,硝基苯化合物对配合物12的荧光性质有不同程度的淬灭作用。它们都对2,4,6-三硝基苯酚的检测具有很好的灵敏性。对其淬灭机理进行了深入的研究。  相似文献   
55.
在溶剂热条件下,合成了3个基于V型配体的Zn(Ⅱ)金属有机骨架:{[Zn2(BIDPS)2(OBA)2]·DMA}n(1)、{[Zn(BIDPT)(PA)]·DMF}n(2)和{[Zn(BIDPS)(PA)(H2O)2]·2H2O}n(3)(BIDPS=4,4''-二(1-咪唑基)苯砜,H2OBA=4,4''-二苯醚二甲酸,H2PA=帕莫酸,BIDPT=4,4''-二(1-咪唑基)苯硫醚)。利用X射线单晶衍射、红外光谱、元素分析、热重分析、X射线粉末衍射对其结构进行了表征。配合物1具有二重穿插的三维cds拓扑网络结构。配合物2为二维(4,4)层状结构,层与层之间通过互锁形成2D→3D的三维金属有机骨架。配合物3具有一维链状结构,一维链通过分子内和分子间氢键连接,形成三维超分子结构。荧光研究表明,配合物1~3可以在pH=4~10的水溶液中稳定存在,且在水中具有较强的发光性能,可作为检测2,4,6-三硝基苯酚和Fe3+的发光传感器,具有较高的灵敏度和选择性。  相似文献   
56.
Paecilomyces catenlannulatus (P. catenlannulatus), a kind of important pathogenic fungi of forest pests, can be regarded as an excellent material to retard the fate and transport of radionuclides. The effect of environmental factors (i.e., pH, ionic strength, temperature and solution concentration) on the uptake of 60Co by P. catenlannulatus was investigated by batch technique. The results showed that the uptake of 60Co by P. catenlannulatus was independent of pH at pH < 5.0, whereas the enhanced uptake of 60Co was observed with increasing pH from 5.0 to 8.0, then remained the high-level uptake at pH > 8.0 due to occurrence of precipitates. It is found that 60Co uptake significantly decreased with increasing ionic strength at low pH, whereas little change was observed at high pH. The pH dependence adsorption indicates that the interaction mechanism between 60Co and P. catenlannulatus is ion exchange at low pH and surface complexation at high pH conditions, respectively. Compared to Freundlich model, the adsorption isotherms can be fitted by Langmuir model very well. The thermodynamic data calculated from the temperature adsorption isotherms indicated that the uptake process of 60Co by P. catenlannulatus was an endothermic and spontaneous process. This paper focused on potential application of P. catenlannulatus as suitable bio-materials for the preconcentration and removal of radionuclides from aqueous solutions in environmental pollution management.  相似文献   
57.
We report a novel strategy for the green synthesis of calcium carbonate (CaCO3) microspheres by using four vegetables: potato, cucumber, aubergine, and carrot. The products were characterized by scanning electron microscopy, X‐ray powder diffractometry and/or Fourier transform infrared spectroscopy. The results show that the spherical calcite crystals are obtained in the presence of potato, cucumber and aubergine extracts, while uniform vaterite and calcite mixed microspheres are produced with the extracts of carrot. The possible formation mechanism of the CaCO3 microspheres by using vegetables is also discussed, suggesting that the biomolecules especially proteins may induce and control the nucleation and growth of CaCO3 crystals. CaCO3 is an important biomineral and inorganic material. Uniform particles have numerous important applications in many areas. Therefore, this study is very significant not only for expanding the scope of crystal engineering, but also for biomineralization research and green synthesis of functional inorganic materials.  相似文献   
58.
测定了河南省主产烟区烤烟K、Cl、Ca、Mg、S、P的含量,结果表明K的含量偏低,其他矿质元素含量正常.元素间的相关性分析结果表明多种矿质元素间存在极显著或显著的相关;对6种矿质元素含量进行因子分析得到2个因子,2个因子的累积贡献率为80.710%.  相似文献   
59.
采用市售廉价大孔α-Al2O3管作为基质材料,通过热浸渍法在管外表面涂敷晶种,随后在无模板剂体系下,利用新型的间歇式水热合成法制备丝光沸石膜。对比了传统加热和间歇式加热对丝光沸石膜形貌、结构及渗透蒸发异丙醇脱水分离性能的差异。考察了合成液中Na2O/SiO2、SiO2/Al2O3和NaF/SiO2物质的量之比在间歇式水热合成下对丝光沸石膜的影响。研究结果表明,当合成液中Na2O/SiO2、SiO2/Al2O3和NaF/SiO2物质的量之比分别为0.24、16.7和0.25时,制备的丝光沸石膜渗透蒸发异丙醇脱水分离性能最佳,在75℃下,对异丙醇/水(9:1,w/w)的渗透通量达5.60 kg·m-2·h-1,水对异丙醇的分离因数大于10 00...  相似文献   
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