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991.
Azobenzene‐Functionalized Metal–Organic Polyhedra for the Optically Responsive Capture and Release of Guest Molecules 下载免费PDF全文
Dr. Jinhee Park Dr. Lin‐Bing Sun Ying‐Pin Chen Zachary Perry Prof. Dr. Hong‐Cai Zhou 《Angewandte Chemie (International ed. in English)》2014,53(23):5842-5846
Stimuli‐responsive metal–organic polyhedra (srMOPs) functionalized with azobenzene showed UV‐irradiation‐induced isomerization from the insoluble trans‐srMOP to the soluble cis‐srMOP, whereas irradiation with blue light reversed this process. Guest molecules were trapped and released upon cis‐to‐trans and trans‐to‐cis isomerization of the srMOPs, respectively. This study provides a new direction in the ever‐diversifying field of MOPs, while laying the groundwork for a new class of optically responsive materials. 相似文献
992.
Youn Jeong Jang Dr. Jae Young Kim Won Yong Kim Prof. Jeong Kon Seo Prof. Sungjee Kim Prof. Kun‐Hong Lee Prof. Jae Sung Lee 《Angewandte Chemie (International ed. in English)》2014,53(23):5852-5857
As a photocathode for CO2 reduction, zinc‐blende zinc telluride (ZnTe) was directly formed on a Zn/ZnO nanowire substrate by a simple dissolution–recrystallization mechanism without any surfactant. With the most negative conduction‐band edge among p‐type semiconductors, this new photocatalyst showed efficient and stable CO formation in photoelectrochemical CO2 reduction at ?0.2–?0.7 V versus RHE without a sacrificial reagent. 相似文献
993.
Inside Back Cover: Patternable Large‐Scale Molybdenium Disulfide Atomic Layers Grown by Gold‐Assisted Chemical Vapor Deposition (Angew. Chem. Int. Ed. 5/2014) 下载免费PDF全文
994.
F. Khoerunnisa D. Minami T. Fujimori S. Y. Hong Y. C. Choi H. Sakamoto M. Endo K. Kaneko 《Adsorption》2014,20(2-3):301-309
We tuned the electronic properties of single wall carbon nanotube (SWCNT) with intercalation of naphthalene derivatives (NDs) having different electron donor or acceptor property in the SWCNT bundles. Characterization of the adsorbed SWCNT with Raman spectroscopy and electrical conductivity measurement clearly indicate the charge transfer interaction of ND molecules with SWCNT. Also X-ray diffraction supports the intercalation of ND molecules in the interstitial spaces and groove sites of SWCNT bundle. Intercalation of ND molecules enhances remarkably the CO2 adsorptivity, which can be ascribed to the key importance of the interaction of the quadrupole moment of CO2 with the local electrical field on the SWCNT induced by the charge transfer interaction. 相似文献
995.
Naphthocrown‐Strapped Calix[4]pyrroles: Formation of Self‐Assembled Structures by Ion‐Pair Recognition 下载免费PDF全文
Dr. Sung Kuk Kim Hong Gyu Lee Dr. Gabriela I. Vargas‐Zúñiga Dr. Vincent M. Lynch Prof. Dr. Cheal Kim Prof. Dr. Jonathan L. Sessler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(37):11750-11759
A new approach to the construction of self‐assembled structures is reported that is based on ion‐pair recognition. Towards this end, the calix[4]pyrrole naphthocrown‐4 hybrid structures 2 and 3 were prepared. These multitopic receptors contain recognition sites for both anions and cations. On the basis of solution‐phase 1H NMR spectroscopic analysis and solid‐state single‐crystal X‐ray diffraction structural studies, it was established that receptors 2 and 3 are able to bind specific ion pairs with high selectivity via different binding modes. In the case of CsF and CsCl, the ion‐pair complexes formed from receptors 2 and 3 were found to self‐assemble to produce either linear supramolecular polymeric crystalline solids or nanotube‐like cyclic hexamers depending on the specific choice of ion pairs and crystallization solvents. Proton NMR studies provided evidence for solution‐phase self‐association in organic media. 相似文献
996.
The First Five‐Membered‐Heterocycle‐Fused Subphthalocyanine Analogues: Chiral Tri(benzo[b]thiopheno)subporphyrazines 下载免费PDF全文
Hong Shang Luyang Zhao Dr. Dongdong Qi Chao Chen Prof. Dr. Jianzhuang Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(49):16266-16272
Two tri(benzo[b]thiopheno)subporphyrazine regioisomers with C3 and C1 molecular symmetry have been isolated from the cyclotrimerization of benzo[b]thiophene‐2,3‐dicarbonitrile as the first five‐membered‐heterocycle‐fused subphthalocyanine analogues. Optical resolution of both regioisomers was achieved by using a chiral HPLC technique, affording the first chiral subphthalocyanine analogues. 相似文献
997.
Dr. Liuyi Li Dr. Zhilin Chen Dr. Hong Zhong Prof. Dr. Ruihu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(11):3050-3060
Two urea‐based porous organic frameworks, UOF‐1 and UOF‐2, were synthesized through a urea‐forming condensation of 1,3,5‐benzenetriisocyanate with 1,4‐diaminobenzene and benzidine, respectively. UOF‐1 and UOF‐2 possess good hydrophilic properties and high scavenging ability for palladium. Their palladium polymers, PdII/UOF‐1 and PdII/UOF‐2, exhibit high catalytic activity and selectivity for Suzuki–Miyaura cross‐coupling reactions and selective reduction of nitroarenes in water. The catalytic reactions can be efficiently performed at room temperature. Palladium nanoparticles with narrow size distribution were formed after the catalytic reaction and were well dispersed in UOF‐1 and UOF‐2. XPS analysis confirmed the coordination of the urea oxygen atom with palladium. SEM and TEM images showed that the original network morphology of UOF‐1 and UOF‐2 was maintained after palladium loading and catalytic reactions. 相似文献
998.
采用电沉积的方法将铁氰化钴(CoHCF)和钴铝水滑石(CoAl-LDH)共同固载于玻碳电极(GCE)表面构筑CoAl-LDH/CoHCF纳米材料修饰电极,并利用CoAl-LDH和CoHCF两种物质在碱性环境中对葡萄糖的协同电催化氧化作用,将其用于葡萄糖的分析。采用扫描电镜对电化学沉积的CoHCF和CoAlLDH的表面形貌进行了表征,利用X射线能量色散谱(EDS)对电沉积的CoAlLDH/CoHCF复合材料进行了分析。采用循环伏安法(CV)对修饰电极催化氧化葡萄糖的行为进行了研究。利用电流-时间法对CoAl-LDH/GCE,CoHCF/GCE,CoAl-LDH/CoHCF/GCE和裸GCE等4种电极对葡萄糖的催化效果进行了对照。对底液NaOH的浓度和扫速对电极的影响进行了探讨。该传感器对葡萄糖在5.0×10–7~6.46×10–4mol/L范围内呈良好的线性响应,相关系数为0.9996,灵敏度为0.13 A·L·mol-1,检出限(S/N=3)为2.1×10–7mol/L。 相似文献
999.
An Aluminophosphate Molecular Sieve with 36 Crystallographically Distinct Tetrahedral Sites 下载免费PDF全文
Jun Kyu Lee Alessandro Turrina Liangkui Zhu Seungwan Seo Dr. Daliang Zhang Dr. Paul A. Cox Prof. Paul A. Wright Prof. Shilun Qiu Prof. Suk Bong Hong 《Angewandte Chemie (International ed. in English)》2014,53(29):7480-7483
The structure of the new medium‐pore aluminophosphate molecular sieve PST‐6 is determined by the combined use of rotation electron diffraction tomography, synchrotron X‐ray powder diffraction, and computer modeling. PST‐6 was prepared by calcination of another new aluminophosphate material with an unknown structure synthesized using diethylamine as a structure‐directing agent, which is thought to contain bridging hydroxy groups. PST‐6 has 36 crystallographically distinct tetrahedral sites in the asymmetric unit and is thus crystallographically the most complex zeolitic structure ever solved. 相似文献
1000.
Aram Hong Chang Min Choi Han Jun Eun Changseop Jeong Prof. Jiyoung Heo Prof. Nam Joon Kim 《Angewandte Chemie (International ed. in English)》2014,53(30):7805-7808
The CD spectroscopy of a chiral compound in solution yields an average CD value derived from all of the conformations of a chiral molecule. By contrast, CD spectroscopy of cold chiral molecules in the gas phase distinguishes specific conformers of a chiral molecule, but the weak CD effect has limited the practical application of this technique. Reported herein is the first resonant two‐photon ionization CD spectra of ephedrines in a supersonic jet using circularly polarized laser pulses, which were generated by synchronizing the oscillation of the photoelastic modulator with the laser firing. The spectra exhibited well‐resolved CD bands which were specific for the conformations and vibrational modes of each enantiomer. The CD signs and magnitudes of the jet‐cooled chiral molecules were very sensitive to their conformations and thus offered crucial information for determining the three‐dimensional structures of chiral species, as conducted in combination with quantum chemical calculations. 相似文献