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1.
Structural Chemistry - In the current study, the energetics of fractionally (and indeed arbitrary non-integer) charged species is explicitly discussed for the enhanced understanding of aromaticity... 相似文献
2.
Analysis and fragmentation mechanisms of hirsutinolide‐type sesquiterpene lactones by ultra‐high‐performance liquid chromatography/electrospray ionization linear ion trap Orbitrap mass spectrometry 下载免费PDF全文
3.
Dr. Jingjun Hao Prof. Arnold L. Rheingold Marzieh Kavand Dr. Kipp J. van Schooten Prof. Christoph Boehme Dr. Marçal Capdevila‐Cortada Prof. Juan J. Novoa Eva Wöss Prof. Günther Knör Prof. Joel S. Miller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12312-12315
The reaction of 2,3,5,6‐tetracyanopyridine (TCNPy) and Cr(C6H6)2 forms diamagnetic σ‐[TCNPy]22? possessing a 1.572(3) Å intrafragment sp3–sp3 bond. This is in contrast to the structurally related 1,2,4,5‐tetracyanobenzene and 1,2,4,5‐tetracyanopyrazine that form π‐dimer dianions possessing long, multicenter bonds. 相似文献
4.
Nonlinear Dynamics - This paper addresses the problem of trajectory tracking control of an underactuated surface vessel moving in a two-dimensional space in the presence of unknown disturbances. In... 相似文献
5.
Optimization Letters - Differential evolution (de) is a popular population-based meta-heuristic that has been successfully used in complex optimization problems. Premature convergence is one of the... 相似文献
6.
Miharu Eguchi Minsu Han Yusuke Asakura Jonathan P. Hill Joel Henzie Katsuhiko Ariga Alan E. Rowan Watcharop Chaikittisilp Yusuke Yamauchi 《Angewandte Chemie (International ed. in English)》2023,62(46):e202307615
Reactions occurring at surfaces and interfaces necessitate the creation of well-designed surface and interfacial structures. To achieve a combination of bulk material (i.e., framework) and void spaces, a meticulous process of “nano-architecting” of the available space is necessary. Conventional porous materials such as mesoporous silica, zeolites, and metal–organic frameworks lack advanced cooperative functionalities owing to their largely monotonous pore geometries and limited conductivities. To overcome these limitations and develop functional structures with surface-specific functions, the novel materials space-tectonics methodology has been proposed for future materials synthesis. This review summarizes recent examples of materials synthesis based on designing building blocks (i.e., tectons) and their hybridization, along with practical guidelines for implementing materials syntheses and state-of-the-art examples of practical applications. Lastly, the potential integration of materials space-tectonics with emerging technologies, such as materials informatics, is discussed. 相似文献
7.
Behnaz Afzalian Joel T. Mague Maryam Mohamadi S. Yousef Ebrahimipour Behjat Pour amiri Esmat Tavakolinejad Kermani 《催化学报》2015,(7):1101-1108
Three complexes containing 2-pyrazinecarboxylate (pzca–), including [Ni(pzca)2(H2O)2], [Co(pzca)2(H2O)2], and [Cu(pzca)2(H2O)2], have been synthesized and characterized using physico-chemical and spectroscopic methods. Furthermore, the structure of each complex was determined by single-crystal X-ray diffraction. All three complexes have an octahedral geometry, where the metal ion chelated by two carboxylate oxygens, two nitrogen atoms belonging to pyrazinic acid molecules, and two oxygen atoms of two water molecules. The catalytic activities of these complex-es were also investigated in the green synthesis of 2H-indazolo[2,1-b]phthalazine-triones by the reaction of hydrazine hydrate with an arylaldehyde, phthalic anhydride, and dimedone in acetic acid. 相似文献
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We characterize the sextic trefoil among plane curves of low degree: first as a complex curve with compact, flat geometry; and then as a curve with meromorphic arc length parameterization. 相似文献
10.
Sashidhar S. Panchamgam Joel L. Plawsky Peter C. Wayner Jr. 《Experimental Thermal and Fluid Science》2006,30(8):745-754
The evaporative heat flux distribution in the leading edge region of a moving evaporating thin liquid film of pentane on quartz was obtained by analyzing the measured thickness profile for thicknesses, δ < 2 μm. The profiles in a constrained vapor bubble were obtained using image analyzing interferometry. Although the evaporating meniscus appeared to be benign (i.e., without additional observed motion beyond creeping), high heat fluxes were obtained. Significantly higher heat fluxes are possible. The interfacial slope, curvature, interfacial shear stress, and liquid pressure profiles were also obtained. Results obtained using a continuum model were consistent with those obtained using a control volume model. The measured pressure field profile of the isothermal extended meniscus agreed with the constant pressure field predicted by the augmented Young–Laplace model. For the non-isothermal case, measured thickness gradients lead to disjoining pressure and curvature gradients for fluid flow and evaporation. The experimental results demonstrate that disjoining pressure at the contact line controls fluid flow within an evaporating completely wetting thin curved film and is, therefore, a useful boundary condition. However, in small interfacial systems, non-idealities can have a dramatic effect. 相似文献