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1.
Continuous administration of most chemotherapeutic drugs can induce different types of side effects. There has been growing interest in exploring an alternative approach to synthesizing compounds that are most effective and have fewer side effects. We synthesized 29H,31H-Phthalocyanine, and Chloro (29H,31H- phthalocyaninato) aluminum at low temperatures using lithium in the present study with diisopropylamide as the nucleophile. The physical characteristics of 29H,31H-Phthalocyanine, and Chloro (29H,31H- phthalocyaninato) aluminum were confirmed by FT-IR method, XRD, SEM, and the impact of these compounds on human colorectal carcinoma (HCT-116) and human cervical cells (HeLa) was examined. Treatment with 29H,31H-Phthalocyanine significantly decreased cancer cell growth and proliferation, as determined by MTT and DAPI staining analysis. In contrast, Chloro (29H,31H- phthalocyaninato) aluminum treatment did not show any inhibitory action on colon or cervical cancer cells. We also calculated the inhibitory concentration (IC50) of 29H,31H-Phthalocyanine, which was 30 µg/ml (HCT-116) and 33 µg/ml (HeLa cells). The antibacterial effectiveness of 29H,31H-Phthalocyanine, and chloro (29H,31H- phthalocyaninato) aluminum was studied using Enterococcus faecalis (E. faecalis). The CFU (colony frequency unit) assay confirmed significant activity against the test bacterium after treatment with 29H,31H-Phthalocyanine. However, no activity was seen upon treatment with chloro (29H,31H- phthalocyaninato) aluminum against E. faecalis.  相似文献   
2.
近年来,设计和合成高性能非富勒烯受体(NFAs)材料已经成为太阳能电池研究领域的前沿课题。基于DA'D型稠环结构的NFAs由于具有吸光系数高、能级和带隙可调、结构易于修饰、分子可高效合成、光电学性能优异等优点而受到了越来越广泛的关注。在短短7年的时间里,能量转换效率(PCE)从3%~4%提高到18%。2019年初邹应萍等报道了一个优秀的受体分子Y6,与PM6共混制备单结电池,获得了15.7%的能量转换效率。Y6类受体材料的中心给电子单元为DA'D型稠环结构,缺电子单元(A')通过氮原子与两个给电子单元(D)并联形成稠环结构,这有助于降低前线分子轨道能级并增强吸收,同时与氮相连的两个烷基链和位于噻吩并噻吩β位的两个侧链则有助于提高溶解度及调节结晶性。自Y6问世以来,人们对分子的结构剪裁进行了深入的研究,并报道了数十种新的结构。在这些新的受体中,DA'D部分的结构裁剪对提高器件效率和太阳能电池的性能起着至关重要的作用。本文对A'、D单元和侧链结构修饰的研究进展进行了综述。通过选择几组受体,对最近报道的分子进行分类,并将它们的光学、电化学、电学和光电性质与精确的结构修饰相关联,从而对结构-性能关系进行全面概述。  相似文献   
3.
以氧化石墨烯(GO)为原料, 利用温和方法制备了3种不同还原程度的部分还原氧化石墨烯pRGO1, pRGO2和pRGO3(pRGO1—3); 利用傅里叶变换红外光谱(FTIR)、 拉曼光谱(Raman)、 X 射线光电子能谱(XPS)、 紫外-可见光谱(UV-Vis)、 透射电子显微镜(TEM)和 EDS能谱对其结构和形貌进行了表征. 细胞实验结果表明, 无激光照射下pRGO1—3本身的细胞毒性较低; 近红外(NIR)激光照射下pRGO1—3通过光热和光毒性双重作用杀伤肿瘤细胞. 实验结果显示了pRGO 在肿瘤光热疗法和光动力疗法领域的应用潜力.  相似文献   
4.
《Mendeleev Communications》2022,32(4):523-526
Five new dyes with D–π–A structure bearing 5-(methylene)-rhodanine-3-acetic acid as an acceptor-anchoring part and thieno[3,2-b]indole or benzo[g]thieno[3,2-b]indole as an electron-donating part were synthesized and applied as photosensitizers for dye-sensitized solar cells (DSSCs). In addition, thermal stability, optical and electrochemical properties of these dyes were investigated. The highest PCE value of 1.09% (Jsc = 3.01 mA cm–2, Voc = 0.53 V, FF = 0.69) was achieved for DSSC based on benzo[g]thieno[3,2-b]indole dye under AM 1.5G irradiation.  相似文献   
5.
Great efforts have been conducted to develop high temperature proton exchange membrane fuel cell (HT-PEMFC) due to its features of enhanced electrocatalyst reactivity, simplified hydrothermal management system and high CO tolerance of catalysts, and remarkable progress has been achieved. However, the easy leaching of phosphoric acid (PA) from the membranes during operation limits its commercial scale-up in complicated environments. This concept here mainly focuses on the recent developments for mitigation of PA loss in PEMs. The probable mechanisms of PA loss are proposed. The approaches to improve PA retention for example via introduction of phosphonic acid by covalent bond, using ion-pairs interaction and siphoning effect, and blending with inorganic nanoparticles are described in detail. Among these strategies, the siphoning effect from the intrinsic microporous PEMs is the most efficient and enables the cell to operate flexibly within a broad temperature range. Therefore, this concept may provide new ideas for the scientists to retain PA, to improve the cell performance and expand the potential applications of PA doped PEMs at elevated humidity and wide temperature range.  相似文献   
6.
There would be a major effect on the cartilage regeneration characteristics of ceramic material in a substrate implant requiring biologically active biomaterials and the reinforcement phase. At this moment, we produced collagen-hyaluronic acid @ hydroxyapatite-halloysite nanotube-single walled carbon nanotube composites, which is a successful technique for making a scaffold with a superior counter for cartilage property. FTIR, XRD, and SEM-EDAX were used to perform morphological and structural studies. The prepared composite's surface feature was investigated and discovered by HRTEM-SAED analysis, and it observed porous nature. The simulated body fluids (SBF) assessment of the materials was noticed their bioactivity and chondrocytes to determine their biocompatibility. Hybrid composite displayed promise for cartilage tissue engineering despite mesenchymal stem cells compatibility effect and magnificently demonstrated an antibacterial effect without antibiotics. The live/dead cells analysis shows that the composite can significantly improve mesenchymal stem cells, and the composite has the potential ability for cartilage regeneration. The above characteristics make the material quite interesting and important in the area for regenerative medicinal uses.  相似文献   
7.
Solar-driven interfacial vaporization by localizing solar-thermal energy conversion to the air−water interface has attracted tremendous attention. In the process of converting solar energy into heat energy, photothermal materials play an essential role. Herein, a flexible solar-thermal material di-cyan substituted 5,12-dibutylquinacridone (DCN−4CQA)@Paper was developed by coating photothermal quinacridone derivatives on the cellulose paper. The DCN−4CQA@Paper combines desired chemical and physical properties, broadband light-absorbing, and shape-conforming abilities that render efficient photothermic vaporization. Notably, synergetic coupling of solar-steam and solar-electricity technologies by integrating DCN−4CQA@Paper and the thermoelectric devices is realized without trade-offs, highlighting the practical consideration toward more impactful solar heat exploitation. Such solar distillation and low-grade heat-to-electricity generation functions can provide potential opportunities for fresh water and electricity supply in off-grid or remote areas.  相似文献   
8.
Yi Li 《中国物理 B》2022,31(9):97301-097301
The rapid development of two-dimensional (2D) materials offers new opportunities for 2D ultra-thin excitonic solar cells (XSCs). The construction of van der Waals heterostructure (vdWH) is a recognised and effective method of integrating the properties of single-layer 2D materials, creating particularly superior performance. Here, the prospects of h-BP/h-BAs vdW heterostructures in 2D excitonic solar cells are assessed. We systematically investigate the electronic properties and optical properties of heterogeneous structures by using the density functional theory (DFT) and first-principles calculations. The results indicate that the heterogeneous structure has good optoelectronic properties, such as a suitable direct bandgap and excellent optical absorption properties. The calculation of the phonon spectrum also confirms the well-defined kinetic stability of the heterstructure. We design the heterogeneous structure as a model for solar cells, and calculate its solar cell power conversion efficiency which reaches up to 16.51% and is higher than the highest efficiency reported in organic solar cells (11.7%). Our work illustrates the potential of h-BP/h-BAs heterostructure as a candidate for high-efficiency 2D excitonic solar cells.  相似文献   
9.
为提升n型叉指背接触(IBC)太阳电池的光电转换效率,采用丝网印刷硼浆和高温扩散的方式形成选择性发射极结构,研究了硼扩散和硼浆印刷工艺对电池发射极钝化性能和接触性能的影响。实验结果表明,在硼扩散沉积时间和退火时间一定的条件下,硼扩散通源(BBr3)流量为100 mL/min,沉积温度为830 ℃,退火温度为920 ℃时,发射极轻掺杂(p+)区域的隐开路电压达到710 mV,暗饱和电流密度为12.2 fA/cm2。发射极局部印刷硼浆湿重为220 mg时,经过高温硼扩散退火,重掺杂(p++)区域的隐开路电压保持在683 mV左右,该区域方块电阻仅46 Ω/□,金属接触电阻为2.3 mΩ·cm2. 采用该工艺方案制备的IBC电池最高光电转换效率达到24.40%,平均光电转换效率达到24.32%,相比现有IBC电池转换效率提升了0.28个百分点。  相似文献   
10.
《中国化学快报》2020,31(7):1782-1786
Anodic electrocatalyst plays the core role in direct alcohol fuel cells (DAFCs), while traditional Pt-catalysts suffer from limited catalytic activity, high over potential and severe CO poisoning. Herein, by selectively depositing Rh atoms on the defective-sites of Pt nanowires (NWs), we developed a new Pt@Rh NW electrocatalyst that exhibited enhanced electrocatalytic performance for both methanol oxidation (MOR) and ethanol oxidation (EOR). Both cyclic voltammetry (CV) and in-situ infrared spectroscopy revealed that the presence of Rh atoms suppressed the generation of poisonous intermediates and completely oxidized alcohols molecule into CO2. Atomic resolusion spherical aberration corrected high-angle annular dark field scanning transmission electron microscopy (CS-HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDS) mapping analysis revealed that Rh atoms were primarily deposited on the defective sites of Pt NWs. Meanwhile, the presence of Rh atoms also modified the electronic state of Pt atoms and therefore lowered the onset potential for alcohols oxidation potential. This work gives the first clear clue on the role of the defective sites of Pt nanocatalyst poisoning, and propose that selectively blocking these sites with trace amount of Rh is an effective strategy in designing advantageous electrocatalysts.  相似文献   
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