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11.
Yiran Li Jun Wang Xiaojun Wang Baoqiang Wang Zhaokun Luan 《Physica C: Superconductivity and its Applications》2011,471(3-4):91-96
The disposal of bayer red mud tailings now seriously threats the environment safety. Reduction and recycling of red mud is now an urgent work in aluminum industry. High gradient superconducting magnetic separation (HGSMS) system was applied to separate the extreme fine RM particles (<100 μm) into high iron content part and low iron content part. Two sorts of RM were fed in the HGSMS. The iron oxide contents in concentrates were about 65% and 45% when RM 1# and RM 2# were fed respectively. Meanwhile, the residues contained 52.0% or 14.1% iron oxide in residues after eight separation stages when RM 1# and RM 2# were fed respectively. The mass recovery of iron concentrates was about 10% after once separation process regardless of RM 1# or RM 2# was fed. Extreme fine particles (<10 μm) could be captured in the HGSMS. Intergrowth of Fe and other elements is disadvantages for iron mineral separation from RM by HGSMS. Some improvement should be studied to enhance the efficiency of iron separation. It is possible for HGSMS to separate RM into high iron content part and low iron content part, the former part could be used in iron-making furnace and the later part could be recycling to sintering process for alumina production or used as construction material. 相似文献
12.
Effect of Axial Ligands on the Molecular Configurations,Stability, Reactivity,and Photodynamic Activities of Silicon Phthalocyanines 下载免费PDF全文
Liqiang Luan Lanlan Ding Jiawei Shi Wenjuan Fang Yuxing Ni Prof. Wei Liu 《化学:亚洲杂志》2014,9(12):3491-3497
To demonstrate the effect of axial ligands on the structure–activity relationship, a series of axially substituted silicon phthalocyanines (SiPcs) have been synthesized with changes to the axial ligands. The reactivity of the axial ligand upon shielding by the phthalocyanine ring current, along with their stability, photophysical, and photodynamic therapy (PDT) activities were compared and evaluated for the first time. As revealed by single‐crystal XRD analysis, rotation of the axial ? OMe ligands was observed in SiPc 3 , which resulted in two molecular configurations coexisting synchronously in both the solid and solution states and causing a split of the phthalocyanine α protons in the 1H NMR spectra that is significantly different from all SiPcs reported so far. The remarkable photostability, good singlet oxygen quantum yield, and efficient in vitro photodynamic activity synergistically show that compound 3 is one of the most promising photosensitizers for PDT. 相似文献
13.
Fu Enfa Zhang Sijia Luan Yu Zhang Yuting Saghir Summaira Xiao Zhenggang 《Cellulose (London, England)》2022,29(3):1727-1737
Cellulose - Most superabsorbent polymers (SAPs) are prepared based on synthetic polymers (from petroleum resources), making them costly, nondegradable, and not ecofriendly. To overcome these... 相似文献
14.
Min Zhou Ximian Xiao Zihao Cong Yueming Wu Wenjing Zhang Pengcheng Ma Sheng Chen Haodong Zhang Danfeng Zhang Donghui Zhang Xiangfeng Luan Prof. Yiyong Mai Prof. Runhui Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7307-7311
Biocompatible and proteolysis-resistant poly-β-peptides have broad applications and are dominantly synthesized via the harsh and water-sensitive ring-opening polymerization of β-lactams in a glovebox or using a Schlenk line, catalyzed by the strong base LiN(SiMe3)2. We have developed a controllable and water-insensitive ring-opening polymerization of β-amino acid N-thiocarboxyanhydrides (β-NTAs) that can be operated in open vessels to prepare poly-β-peptides in high yields, with diverse functional groups, variable chain length, narrow dispersity and defined architecture. These merits imply wide applications of β-NTA polymerization and resulting poly-β-peptides, which is validated by the finding of a HDP-mimicking poly-β-peptide with potent antimicrobial activities. The living β-NTA polymerization enables the controllable synthesis of random, block copolymers and easy tuning of both terminal groups of polypeptides, which facilitated the unravelling of the antibacterial mechanism using the fluorophore-labelled poly-β-peptide. 相似文献
15.
Xiangfeng Luan Dr. Cristina Martín Pengfei Zhang Qian Li Dr. Isabella Anna Vacchi Prof. Lucia Gemma Delogu Prof. Yiyong Mai Dr. Alberto Bianco 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18673-18679
As an emerging member of the graphene family, structurally defined graphene nanoribbons (GNRs) have shown promising applications in various fields. The evaluation of the degradability of GNRs is particularly important for assessing the persistence level and risk of these materials in living organisms and the environment. However, there is a void in the study of the degradation of GNRs. Here, we report the degradation behavior of GNRs in the presence of human myeloperoxidase (hMPO) or treated with the photo-Fenton (PF) reaction. With the assistance of potassium hydroxide or imidazole, which facilitates the dispersion of GNRs in the aqueous solution, GNRs underwent only partial degradation after 25-hour incubation with hMPO, while, the PF reaction degraded GNRs almost completely after 120 hours. These results indicate that structurally precise GNRs can be efficiently degraded under suitable conditions, providing more opportunities for future applications in different fields. 相似文献
16.
Peng Zhang Xue Feng Lu Deyan Luan Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2020,59(21):8128-8132
Photocatalysts with well‐designed compositions and structures are desirable for achieving highly efficient solar‐to‐chemical energy conversion. Heterostructured semiconductor photocatalysts with advanced hollow structures possess beneficial features for promoting the activity towards photocatalytic reactions. Here we develop a facile synthetic strategy for the fabrication of Fe2TiO5–TiO2 nanocages (NCs) as anode materials in photoelectrochemical (PEC) water splitting cells. A hydrothermal reaction is performed to transform MIL‐125(Ti) nanodisks (NDs) to Ti–Fe–O NCs, which are further converted to Fe2TiO5–TiO2 NCs through a post annealing process. Owing to the compositional and structural advantages, the heterostructured Fe2TiO5–TiO2 NCs show enhanced performance for PEC water oxidation compared with TiO2 NDs, Fe2TiO5 nanoparticles (NPs) and Fe2TiO5–TiO2 NPs. 相似文献
17.
Qi Zhang Jingyi Luan Yougen Tang Xiaobo Ji Haiyan Wang 《Angewandte Chemie (International ed. in English)》2020,59(32):13180-13191
Aqueous zinc‐ion batteries have rapidly developed recently as promising energy storage devices in large‐scale energy storage systems owing to their low cost and high safety. Research on suppressing zinc dendrite growth has meanwhile attracted widespread attention to improve the lifespan and reversibility of batteries. Herein, design methods for dendrite‐free zinc anodes and their internal mechanisms are reviewed from the perspective of optimizing the host–zinc interface and the zinc–electrolyte interface. Furthermore, a design strategy is proposed to homogenize zinc deposition by regulating the interfacial electric field and ion distribution during zinc nucleation and growth. This Minireview can offer potential directions for the rational design of dendrite‐free zinc anodes employed in aqueous zinc‐ion batteries. 相似文献
18.
Reu P. L. Blaysat B. Andó E. Bhattacharya K. Couture C. Couty V. Deb D. Fayad S. S. Iadicola M. A. Jaminion S. Klein M. Landauer A. K. Lava P. Liu M. Luan L. K. Olufsen S. N. Réthoré J Roubin E. Seidl D. T. Siebert T. Stamati O. Toussaint E. Turner D. Vemulapati C. S. R. Weikert T. Witz J. F. Witzel O. Yang J. 《Experimental Mechanics》2022,62(4):639-654
Experimental Mechanics - The DIC Challenge 2.0 follows on from the work accomplished in the first Digital Image Correlation (DIC) Challenge Reu et al. (Experimental Mechanics 58(7):1067, 1). The... 相似文献
19.
利用2,4-二硝基氟苯为柱前衍生试剂,建立了测定山黧豆中毒素β-Ν-草酰基-L-α,β-二氨基丙酸(简称-βODAP)及其无毒性的异构体α-N-草酰基-L-α,β-二氨基丙酸(简称α-ODAP)的恒组分洗脱高效液相色谱方法。利用固相萃取进行样品预处理并优化了流动相的pH值,利用Hyperchem和Gaussian 98优化得到二者的空间结构并计算了它们的极性,从理论上解释了两个异构体的色谱行为。最佳色谱条件是固定相C18,5μm,15 mm×4.6 mm,流动相为25 mmol/L KH2PO4/乙腈,(90∶10,V/V),流速为0.8 mL/m in,室温,测定了特定条件下山黧豆成长过程中两个异构体的含量。 相似文献
20.