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41.
Mingming Peng Quanzheng Deng Yuhong Zhao Prof. Hao Xu Prof. Yejun Guan Dr. Jingang Jiang Prof. Lu Han Prof. Peng Wu 《Angewandte Chemie (International ed. in English)》2023,62(15):e202217004
A high-silica zeolite ECNU-13 (Si/Al=23) with a new three-dimensional (3D) pore system and a nanosized morphology has been developed, consisting of multitudes of 10-membered ring (10-R) medium pores and one set of 8-R small pores. A phase-discrimination strategy was proposed to synthesize ECNU-13 by regulating the gel compositions and nucleation processes that were used for preparing 12-R large-pore germanosilicate IM-20 with the known UWY topology. The crystallization was directed towards forming one set of single four-ring (s4r) composite building units together with one set of double four-ring (d4r) rather than two different types of d4r units in IM-20. The electron crystallographic investigations elucidated that the ECNU-13 structure was composed of two kinds of polymorphs as a result of distinct atomic positionings in s4r units. In catalytic cracking of 1-butene, ECNU-13 exhibited high propene selectivity (55.6 %) and propene to ethylene molar ratio (>4.7) superior to well-studied conventional ZSM-5 zeolite catalyst. 相似文献
42.
Xiang Chen Dr. Shuhui Guan Jianjiang Zhou Hengjun Shang Jingyuan Zhang Fujian Lv Prof. Han Yu Prof. Dr. Hexing Li Prof. Zhenfeng Bian 《Angewandte Chemie (International ed. in English)》2023,62(45):e202312734
Single-atom catalysts (SACs) have emerged as crucial players in catalysis research, prompting extensive investigation and application. The precise control of metal atom nucleation and growth has garnered significant attention. In this study, we present a straightforward approach for preparing SACs utilizing a photocatalytic radical control strategy. Notably, we demonstrate for the first time that radicals generated during the photochemical process effectively hinder the aggregation of individual atoms. By leveraging the cooperative anchoring of nitrogen atoms and crystal lattice oxygen on the support, we successfully stabilize the single atom. Our Pd1/TiO2 catalysts exhibit remarkable catalytic activity and stability in the Suzuki–Miyaura cross-coupling reaction, which was 43 times higher than Pd/C. Furthermore, we successfully depose Pd atoms onto various substrates, including TiO2, CeO2, and WO3. The photocatalytic radical control strategy can be extended to other single-atom catalysts, such as Ir, Pt, Rh, and Ru, underscoring its broad applicability. 相似文献
43.
Dr. Lina Xie Dr. Le Shi Dr. Kai Xiong Dr. Ruilin Guan Prof. Dr. Yu Chen Prof. Dr. Jiangang Long Prof. Liangnian Ji Prof. Dr. Hui Chao 《欧洲无机化学杂志》2023,26(15):e202300001
Two novel unsymmetrical Ir(III) complexes [Ir(ppy)2(N N)Cl2] (N N=2-(pyrazin-2-yl)naphtha[1,2-e][1,2,4]triazine, Ir1 ; 2-(pyrazin-2-yl)-4b,4b’-dihydroaceanthryleno[1,2-e][1,2,4]triazine, Ir2 ) were developed as chemotherapy agents. Ir1 was mainly located in mitochondria. In contrast, Ir2 accumulated in mitochondria but subsequently migrated to the nucleus. Ir1 and Ir2 showed cytotoxicity toward cancerous cells, especially the cisplatin-resistant ones, indicating their ability to overcome cisplatin resistance. Although both Ir1 and Ir2 disrupted mitochondrial metabolism, they showed different cell death mechanisms. Ir1 induced mitochondria-mediated apoptosis in cisplatin-resistant A549R cells. Ir2 was demonstrated to cause PARP-1 activated necroptosis in A549R cells. This study provides an experimental basis for the rational design of metal-based chemotherapeutic drugs. 相似文献
44.
Xiuxia Sun Qi Chen Angelique A. Guan Shuaishuai Yuan Zhibo Li 《Macromolecular bioscience》2023,23(10):2300146
Abdominal wall defect caused by surgical trauma, congenital rupture, or tumor resection may result in hernia formation or even death. Tension-free abdominal wall defect repair by using patches is the gold standard to solve such problems. However, adhesions following patch implantation remain one of the most challenging issues in surgical practice. The development of new kinds of barriers is key to addressing peritoneal adhesions and repairing abdominal wall defects. It is already well recognized that ideal barrier materials need to have good resistance to nonspecific protein adsorption, cell adhesion, and bacterial colonization for preventing the initial development of adhesion. Herein, electrospun poly(4-hydroxybutyrate) (P4HB) membranes infused with perfluorocarbon oil are used as physical barriers. The oil-infused P4HB membranes can greatly prevent protein attachment and reduce blood cell adhesion in vitro. It is further shown that the perfluorocarbon oil-infused P4HB membranes can reduce bacterial colonization. The in vivo study reveals that perfluoro(decahydronaphthalene)-infused P4HB membranes can significantly prevent peritoneal adhesions in the classic abdominal wall defects’ model and accelerate defect repair, as evidenced by gross examination and histological evaluation. This work provides a safe fluorinated lubricant-impregnated P4HB physical barrier to inhibit the formation of postoperative peritoneal adhesions and efficiently repair soft-tissue defects. 相似文献
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46.
Cyclometalated Iridium(III) Complexes as Two‐Photon Phosphorescent Probes for Specific Mitochondrial Dynamics Tracking in Living Cells 下载免费PDF全文
Chengzhi Jin Jiangping Liu Dr. Yu Chen Leli Zeng Ruilin Guan Cheng Ouyang Prof. Liangnian Ji Prof. Dr. Hui Chao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(34):12000-12010
Five cyclometalated iridium(III) complexes with 2‐phenylimidazo[4,5‐f][1,10]phenanthroline derivatives ( IrL1 – IrL5 ) were synthesized and developed to image and track mitochondria in living cells under two‐photon (750 nm) excitation, with two‐photon absorption cross‐sections of 48.8–65.5 GM at 750 nm. Confocal microscopy and inductive coupled plasma‐mass spectrometry (ICP‐MS) demonstrated that these complexes selectively accumulate in mitochondria within 5 min, without needing additional reagents for membrane permeabilization, or replacement of the culture medium. In addition, photobleaching experiments and luminescence measurements confirmed the photostability of these complexes under continuous laser irradiation and physiological pH resistance. Moreover, results using 3D multicellular spheroids demonstrate the proficiency of these two‐photon luminescent complexes in deep penetration imaging. Two‐photon excitation using such novel complexes of iridium(III) for exclusive visualization of mitochondria in living cells may substantially enhance practical applications of bioimaging and tracking. 相似文献
47.
以1-乙烯基-3-乙酸乙酯咪唑氯离子液体为功能单体,以再生纤维素膜为基膜,采用温和的表面ATRP接枝聚合技术在水溶液中制备了溶菌酶分子印迹膜.通过紫外-可见光谱分析了离子液体与模板分子的作用力,讨论了功能单体1-乙烯基-3-乙酸乙酯咪唑氯用量对印迹复合膜性能的影响,研究了分子印迹复合膜对溶菌酶模板分子及其结构类似物的吸附行为和选择性识别特性.结果表明,以1-乙烯基-3-乙酸乙酯咪唑氯离子液体作为功能单体的溶菌酶分子印迹膜能够从结构类似物混合体系中选择性分离富集溶菌酶,且具有很好的稳定性和可再生性能. 相似文献
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49.
Qing-Qing Guan Xiao-Dian Huang Yan-Hua Zeng Chao-Hai Wei Ping Ning Gu Jun-Jie Xin-Sheng Chai 《Chemical Papers》2015,69(5):662-667
This paper reports a headspace analysis technique for the determination of products, i.e., cyclohexanone (CE) and cyclohexanol (CL), of phenol hydrogenation in a supercritical water reaction system (SWRS) with water removal by hydrate formation. An addition of anhydrous calcium chloride leads to water absorption resulting in crystal water; thus, the samples can be quantitatively measured without the influence of water. After achieving equilibrium at 150°C and maintaining it for 5 min, the obtained results showed a relative standard deviation of less than 5.3% and the recovery ranged from 93% to 104%. The presented method is simple and accurate for the analysis of CL, CE and phenol in samples from phenol conversion in SWRS. 相似文献
50.