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101.
Sisi Chen Vincent Scholiers Mengyao Zhang Jiandong Zhang Prof. Dr. Jian Zhu Prof. Dr. Filip E. Du Prez Prof. Dr. Xiangqiang Pan 《Angewandte Chemie (International ed. in English)》2023,62(49):e202309652
Covalent adaptable networks (CANs) possess unique properties as a result of their internal dynamic bonds, such as self-healing and reprocessing abilities. In this study, we report a thermally responsive C−Se dynamic covalent chemistry (DCC) that relies on the transalkylation exchange between selenonium salts and selenides, which undergo a fast transalkylation reaction in the absence of any catalyst. Additionally, we demonstrate the presence of a dissociative mechanism in the absence of selenide groups. After incorporation of this DCC into selenide-containing polymer materials, it was observed that the cross-linked networks display varying dynamic exchange rates when using different alkylation reagents, suggesting that the reprocessing capacity of selenide-containing materials can be regulated. Also, by incorporating selenonium salts into polymer materials, we observed that the materials exhibited good healing ability at elevated temperatures as well as excellent solvent resistance at ambient temperature. This novel dynamic covalent chemistry thus provides a straightforward method for the healing and reprocessing of selenide-containing materials. 相似文献
102.
Dr. Jian Li Lei Zhu Prof. Dr. Chen-Ho Tung Prof. Dr. Li-Zhu Wu 《Angewandte Chemie (International ed. in English)》2023,62(22):e202301384
Graphdiyne (GDY) with a direct band gap, excellent carrier mobility and uniform pores, is regarded as a promising photocatalytic material for solar energy conversion, while the research on GDY in photocatalysis is a less developed field. Herein, the distinctive structure, adjustable band gap, and electronic properties of GDY for photocatalysis is firstly summarized. The construction and progress of GDY-based photocatalysts for solar energy conversion, including H2 evolution reaction (HER), CO2 reduction reaction (CO2RR) and N2 reduction reaction (NRR) are then elaborated. At last, the challenges and perspectives in developing GDY-based photocatalysts for solar fuel production are discussed. It is anticipated that a timely Minireview will be helpful for rapid progress of GDY in solar energy conversion. 相似文献
103.
Mengdi Lv Yue Zheng Jian Wu Zhengqi Shen Binglian Guo Guojing Hu Yuanlei Huang Jingyue Zhao Prof. Yong Qian Prof. Zhi Su Prof. Chao Wu Prof. Xuling Xue Prof. Hong-Ke Liu Prof. Zong-Wan Mao 《Angewandte Chemie (International ed. in English)》2023,62(48):e202312897
Ferroptosis is a form of programmed cell death driven by iron-dependent lipid peroxidation (LPO) with the potential for antitumor immunity activation. In this study, a nonferrous cyclopentadienyl metal-based ferroptosis inducer [Ir(Cp*)(Bet)Cl]Cl ( Ir-Bet ) was developed by a metal-ligand synergistic enhancement (MLSE) strategy involving the reaction of [Ir(Cp*)Cl]2Cl2 with the natural product Betulin. The fusion of Betulin with iridium cyclopentadienyl (Ir-Cp*) species as Ir-Bet not only tremendously enhanced the antiproliferative activity toward cancer cells, but also activated ferritinophagy for iron homeostasis regulation by PI3K/Akt/mTOR cascade inhibition with a lower dosage of Betulin, and then evoked an immune response by nuclear factor kappa-B (NF-κB) activation of Ir-Cp* species. Further immunogenic cell death (ICD) occurred by remarkable ferroptosis through glutathione (GSH) depletion, glutathione peroxidase 4 (GPX4) deactivation and ferritinophagy. An in vivo vaccination experiment demonstrated desirable antitumor and immunogenic effects of Ir-Bet by increasing the ratio of cytotoxic T cells (CTLs)/regulatory T cells (Tregs). 相似文献
104.
Guodong Ju Zhibin Huang Jian Liu Xu Xu Zefeng Deng Prof. Yingsheng Zhao 《European journal of organic chemistry》2023,26(36):e202300596
A strategy for the synthesis of diverse protected α-monofluoro-γ-amino acid derivatives has been developed. This reaction assembles a simple enamide, quinoxalin-2(1H)-one, and diethyl 2-bromo-2-fluoromalonate through a three-component reaction driven by visible light. The advantages of this protocol include the simplicity of its operation, mild conditions, high functional group tolerance, and applicability to a wide variety of substrates. The synthesis of this fluorine-containing amino acid derivative has significant value for potential applications in medicinal chemistry and chemical biology. 相似文献
105.
The realization of ferromagnetic ordering of two-dimensional (2D) carbon material graphdiyne (GDY) has attracted great attention due to its promising application in spin semiconductor devices. However, the absence of localized spins makes the pristine GDY intrinsically nonferromagnetic. Herein, we report the realization of robust room-temperature (RT) ferromagnetism (FM) with Curie temperature (TC) up to 325 K for GDY Nanosheets (GDYNs) by supercritical CO2 (SC CO2). Experimental and theoretical calculations reveal that the new chemical bond of C−O−Si can be formed because of the unique effect of SC CO2, which help to enhance the charge transfer and generates long-range ferromagnetic order. The RT saturation magnetization (MS) reaches 1.125 emu/g, which is much higher than that of carbon-based materials reported up to now. Meanwhile, by changing the conditions of SC CO2 such as pressure, ferromagnetic responses can be manipulated, which is great for potential spintronics applications of GDY. 相似文献
106.
Jie Sun Prof. Dr. Zhenjiang Liu Prof. Dr. Jian Jin 《European journal of organic chemistry》2023,26(13):e202300081
A modular protocol for the triarylamine synthesis has been developed using diarylamines and electron-rich arenes, such as phenols, as the building blocks. The KI/KIO4 system proves to be highly efficient for the cross-dehydrogenative coupling of phenothiazines/phenoxazines with phenols/anilines. A wide range of functional groups attached to both coupling partners were well tolerated. Through the manipulation of reaction temperatures, the sequential assembly of bis-triarylamines could be achieved to provide the unsymmetrically bis-aminated phenols efficiently. Furthermore, the multiple aminated polyphenols were rapidly constructed in good to high yields by a single operation. 相似文献
107.
土壤水溶性盐是表征土壤盐碱化程度的重要指标,也是评价耕地地力的重要参数,被纳入第三次全国土壤普查(“三普”)监测指标体系中。重量法是测定土壤水溶性盐总量的最常用方法,其测定过程易受多种因素影响,导致其测定结果不准。鉴于此,本文设计试验分别验证了水溶性盐浸提和浸提液固液分离这两个过程对测定结果的影响,结果表明浸提液固液分离是影响土壤水溶性盐总量测定准确度和精密度的主要因素。基于此进一步探究4种不同固液分离方式(布氏漏斗过滤、滤膜真空抽滤、离心、滤纸组合过滤)对测定结果的影响,结果表明相较于其它方式,滤纸组合过滤测定结果准确度高,适用于土壤水溶性盐总量的测定。对改进后的重量法测定土壤水溶性盐总量进行方法学确认,结果表明其检出限为0.01 g/kg,测定下限为0.04 g/kg;方法的准确度和精密度、适用范围等均符合相关要求。本文推荐的土壤水溶性盐总量测定方法为:土壤样品采用1:5土水比浸提,180 r/min振荡3 min,浸提液采用滤纸组合自然过滤;其测定结果的准确度和精密度符合相关要求。本文旨在为“三普”内业检测提供参考和借鉴,为全面摸清不同区域土壤水溶性盐含量水平及土壤盐渍化程度提供技术支撑。 相似文献
108.
109.
提出了柱前衍生反相高效液相色谱法测定陶瓷饰品中六价铬溶出量的方法。采用人工汗液萃取陶瓷饰品,用1,5-二苯卡巴肼与萃取液中的六价铬在酸性条件下进行衍生反应,衍生物在Waters SunFire ODS C18色谱柱上分离,以pH 2.5的10mmol·L-1磷酸二氢钾缓冲溶液和丙酮为流动相进行梯度洗脱,于波长540nm处进行测定。六价铬的质量浓度在5.0~200.0μg·L-1范围内与峰面积呈线性关系,相关系数为0.999 1,检出限(3S/N)为0.037μg·L-1。空白(实际样品)的加标回收率在97%~101%之间,测定值的相对标准偏差在1.9%~3.2%之间。 相似文献
110.
通过2-(4'-三氟乙酰苯基)-4-苯基喹啉(tfapqH)与三氯化铱反应生成了二氯桥中间体,然后用吡啶-2-甲酸(picH)解离得到双环金属铱配合物Ir(tfapq)2pic。Ir(tfapq)2pic在二氯甲烷中的发光波长为584 nm,量子产率约为0.846,磷光寿命为1.211 μs,比没有三氟乙酰修饰的铱配合物波长蓝移的10 nm,量子效率提高了约5%,磷光寿命降低了0.286 μs,辐射跃迁加快,半波宽度降低了约26%,色纯度提高。其HOMO能级为-5.405 eV,LUMO能级为-3.277 eV,能级相对于未修饰的配合物都有所降低,且HOMO降低更明显,总的效果是能级差增加。Ir(tfapq)2pic 10%的热失重温度为301 ℃,比未修饰铱配合高近50 ℃。当Ir(tfapq)2pic以2%质量浓度掺杂于PVK-PBD中做成电致发光器件时的效率最高,电致发光波长为594 nm。器件的启明电压为7.3 V,最大亮度为8 571 cd·m-2,最大外量子效率为12.65%,对应的流明效率为22.14 cd·A-1。色坐标是(0.58,0.40)。 相似文献