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981.
Nie Renwang Wu Qingyong Yu Zhuqing Wang Aiguo Shen Xiaodong 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6643-6654
Journal of Thermal Analysis and Calorimetry - Coral wastes are produced during the construction of island. The use of coral wastes in concrete is beneficial to economy and environment. Coral waste... 相似文献
982.
Dehydrogenation of an organic compound is the first and the most fundamental elementary reaction in many organic reactions. In ethanol oxidation reaction (EOR) to form CO2, there are a total of 46 pathways in C2HxO (x=1–6) species leading to the removal of all six hydrogen atoms in five C−H bonds and one O−H bond. To investigate the degree of dehydrogenation in EOR under operando conditions, we performed density function theory (DFT) calculations to study 28 dehydrogenation steps of C2HxO on Ir(100). An activation energy surface was then constructed and compared with that of the C−C bond cleavages to understand the importance of the degree of dehydrogenation in EOR. The results show that there are likely 28 dehydrogenations in EOR under fuel cell temperatures and the last two hydrogens in C2H2O are less likely cleaved. On the other hand, deep dehydrogenation including 45 dehydrogenations can occur under ethanol steam reforming conditions. 相似文献
983.
金属锂因具有极高的理论比容量(3860 mAh/g)和最低的电化学势(相对于标准氢电极为-3.04 V),被认为是下一代高比能锂离子电池的首选负极材料。然而,金属锂负极在电池循环过程中发生的刺状枝晶生长和体积变化等问题严重阻碍了其产业化应用进程。近年来研究表明,通过在金属锂中引入具有三维(3D)结构的宿主骨架,不但能有效抑制锂枝晶的生长,而且可以缓解金属锂负极的体积变化,从而提高金属锂电池的循环性能与安全性。因此,设计3D骨架/金属锂复合负极被认为是一种能有效解决金属锂问题的新兴策略。本文综述了热熔灌输法制备3D骨架/金属锂复合负极的研究进展。首先讨论了当前基于3D骨架的预存金属锂技术,然后着重分析了热熔灌输策略中3D骨架锂润湿性的影响因素,以及不同3D骨架修饰特征和改性方法。最后对3D骨架/金属锂复合负极和热熔灌输策略现存问题进行了总结并提出未来的发展方向。 相似文献
984.
Saiji Shen Chu Wu Yinghui Shang Hongdou Shen Yue Liao Yuting Guo Min Hu Xia Wang Gang Li Qigang Wang 《中国科学:化学(英文版)》2022,65(1):153-161
There are several natural materials which have evolved functional gradients,ingeniously attaining maximal efficacy from limited components.Herein,we utilized the spatiotemporal distribution of initiator acetylacetone to regulate the multienzyme polymerization and fabricate a chitosan-polymer hydrogel.The temporal priority order of acetylacetone was higher than phenolmodified chitosan by density functional theory calculation.The acetylacetone within the gelatin could gradually diffuse spatially into the chitosan hydrogel to fabricate the composite hydrogel with gradient network structure.The gradient hydrogel possessed a transferring topography from the two-dimensional pattern.A continuously decreased modulus along with acetylacetone diffusion was confirmed by atomic force microscope-based force mapping experiment.The water-retaining ability of various regions was confirmed by low-field nuclear magnetic resonance(NMR)and thermogravimetric analysis(TG)analysis,which led to the spontaneous actuation of gradient hydrogel with maximum 1821°/h curling speed and 227°curling angle.Consequently,the promising gradient hydrogels could be applied as intelligent actuators and flexible robots. 相似文献
985.
Li Yang Li-yuan Xie Xuan Chen Xiao-hong Bai Shuang Hu 《Journal of separation science》2022,45(13):2252-2261
A novel solvent terminated microextraction method based on a natural deep eutectic solvent (L-menthol and lactic acid at a molar ratio of 1:2) coupled with high-performance liquid chromatography was proposed, which was utilized for the separation and enrichment of bisdemethoxycurcumin, demethoxycurcumin and curcumin in Curcumae Longae Rhizoma and turmeric tea. The effects of independent parameters on extraction efficiency were optimized by single-factor analysis. Subsequently, four predominated parameters affecting the extraction procedure, including extractant volume, salt concentration, demulsifier consumption, and demulsification time, were further evaluated by a central composite design. Under the optimized conditions, the linear ranges of calibration curves were 0.005–0.5 μg/mL for bisdemethoxycurcumin, 0.004–0.4 μg/mL for demethoxycurcumin, and 0.0045–0.45 μg/mL for curcumin, respectively. In addition, the developed method provided low detection limits (0.1–0.4 ng/mL) and high enrichment factors (279–350). Its intra-day and inter-day precision were carried out by relative standard deviation ranging from 2.2 to 9.2%. Finally, the applicability of this method was assessed by the analysis of Curcumae Longae Rhizoma and turmeric tea samples. The results showed that these samples were detected successfully and the spiked recoveries over the range of 85.3-108.9% with relative standard deviations of 1.6-8.9% were attained, indicating its high relative recoveries with good precision in real sample analysis. 相似文献
986.
Karuppasamy Kohila Rani Rajkumar Devasenathipathy Jia-Zheng Wang Xiao-Yuan Hui Jian-De Lin Yi-Miao Zhang Liu-Bin Zhao Jian-Zhang Zhou De-Yin Wu Zhong-Qun Tian 《Current Opinion in Electrochemistry》2022
Plasmonic noble metal nanostructures have been targeted due to their strong surface plasmon resonance at photoelectrochemical interfaces. Recently, it has been concluded that, the plasmonic noble metal nanostructures on photoexcitation permit the transfer of effective hot carriers (hot electron/hole pair) to nearby adsorbed molecules where, the transformed hot carriers can efficiently decrease the activation barrier of a reaction. In this review, our recent achievements in the plasmon-mediated chemical reactions of organic molecules such as para-aminothiophenol, substituted para-aminothiophenol and para-nitrothiophenol at nanostructures modified noble metal electrodes using surface enhanced Raman spectroscopy, electrochemical methods, and theoretical calculations will be discussed. 相似文献
987.
Ke Yang Yi Zhou Yaping Wang Dr. Shaojing Zhao Xiaoli Wu Dr. Xiao Peng Li Huang Lirong Jiang Prof. Minhuan Lan Prof. Xiao-Yi Yi 《化学:亚洲杂志》2021,16(13):1780-1785
Image-guided photodynamic therapy (PDT) has received growing attention due to its non-invasiveness and precise controllability. However, the PDT efficiency of most photosensitizers are decreased in living system due to the aggregation-caused singlet oxygen (1O2) generation decreasing. Herein, we present an Iridium (III) pyridylpyrrole complex (Ir-1) featuring of aggregation-induced emission (AIE) and 1O2 generation characteristics for image-guided PDT of cancer. Ir-1 aqueous solution exhibits bright red phosphorescence peaked at 630 nm, large Stokes shift of 227 nm, and good 1O2 generation ability. The 1O2 generating rate of Ir-1 in EtOH/water mixture solution is 2.3 times higher than that of Rose Bengal. In vitro experimental results revealed that Ir-1 has better biocompatibility and higher phototoxicity compared with clinically used photosensitizers (Rose Bengal and Ce6), suggesting that Ir-1 can serve as a photosensitizer for image-guided PDT of cancer. 相似文献
988.
Jiankang Deng Jing Hu Juanjuan Zhao Nan An Kuijing Liang Qinghua Wang Zhiqiang Zhang Rongrong Wu Fuyuan Zhang 《Arabian Journal of Chemistry》2021,14(7):103195
This study established a ferric ion (Fe3+) detection method as a result of the fluorescence quenching effect of Fe3+ on carbon dots (CDs). Specifically, we proposed, a green microwave synthesis route towards fluorescent CDs that requires only the brewer’s spent grain as starting materials. Transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectra and X-ray photoelectron spectroscopy were performed to investigate the CDs characteristic: morphology, size distribution, functional groups, and composition, respectively. The experimental results, which were run under optimal experimental conditions, indicated that the fluorescence intensity and concentration of Fe3+ were within the desired linear range (0.3–7 μM). The detection limit of this assay towards Fe3+ was 95 nM. The proposed method showed significant selectivity with respect to interfering ions. We evaluated the potential application of this method with tap water, lake water and fetal bovine serum as real samples. Additionally, the CDs could be served as superior bioimaging probes in Hela cells as a result of their excellent optical stability and good biocompatibility. In a word, the present study provides a new idea for CDs derived from the waste of agricultural products for detecting food or environmental contaminants and cell imaging. 相似文献
989.
As the energy density of state-of-the-art lithium (Li)-ion batteries (LIBs) increases, the safety concern of LIBs using liquid electrolytes is drawing increasing attention. Flammability of electrolytes is a critical link of the overall safety performance of LIBs and Li metal batteries. For this reason, intensive efforts have been devoted to suppressing the flammability of liquid electrolytes. In this short review, the common approaches to reduce the flammability of the nonaqueous liquid electrolytes will be summarized. The advantages and limitations of these approaches will also be discussed. 相似文献
990.
Nucleic acid–based electrochemical sensors are ideally suited to the detection of molecular targets for which enzymatic detection or direct electrochemical oxidation – reduction reactions are not possible. Moreover, the versatility of nucleic acids in their ability to bind a great variety of target types, from small molecules to single-entity mesoscopic targets, makes them attractive receptors for the development of electrochemical biosensors. In this brief opinion piece, we discuss field advances from the past two years. We hope the works highlighted here will inspire the community to pursue creative designs enabling the detection of larger and more complex targets with a specific focus on analytical validation and translation into preclinical or clinical applications. 相似文献