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11.
In this paper, we study the Heinz type inequalities for mappings satisfying Poisson’s equation. Some results generalize the ones obtained by Partyka and Sakan. 相似文献
12.
Two LnIII ions are sandwiched by dinuclear CoII building blocks derived from a tris‐triazamacrocyclic ligand bearing pendant carboxylic acid functionality, 1,3,5‐tris((4,7‐bis(2‐carboxyethyl)‐1,4,7‐triazacyclonon‐1‐yl)methyl)‐benzene (H6L), giving rising to two nanoscale heterometallic metal–organic cages formulated as [Co4Ln2(LH2.5)2(H2O)4]·(ClO4)6·NO3·nH2O [Ln = Dy, n = 12 ( 1 ); Ln = Yb, n = 9 ( 2 )], whose internal cavity accommodates a guest NO3? anion. Their hexanuclear cage‐like architectures are maintained both in solution and solid states as confirmed by mass spectrum as well as X‐ray diffraction experiments. These two cages display ligand‐based fluorescence emissions and therefore both were chosen to be operated as fluorescent chemosensors for the detection of nitroaromatic compounds. Attractively, these metal–organic cages allow highly selective and sensitive detection of picric acid (PA) over other nitroaromatics in solution and suspension, and the fluorescence resonance energy transfer (FRET) between the cage probes and PA is mainly responsible for the remarkable detection efficiency. 相似文献
13.
Hui‐Min Lin Jian‐Rong Li Chao Mu Ao Li Xu‐Feng Liu Pei‐Hua Zhao Yu‐Long Li Zhong‐Qing Jiang Hong‐Ke Wu 《应用有机金属化学》2019,33(11)
Five monophosphine‐substituted diiron propane‐1,2‐dithiolate complexes as the active site models of [FeFe]‐hydrogenases have been synthesized and characterized. Reactions of complex [Fe2(CO)6{μ‐SCH2CH(CH3)S}] ( 1 ) with a monophosphine ligand tris(4‐methylphenyl)phosphine, diphenyl‐2‐pyridylphosphine, tris(4‐chlorophenyl)phosphine, triphenylphosphine, or tris(4‐fluorophenyl)phosphine in the presence of the oxidative agent Me3NO·2H2O gave the monophosphine‐substituted diiron complexes [Fe2(CO)5(L){μ‐SCH2CH(CH3)S}] [L = P(4‐C6H4CH3)3, 2 ; Ph2P(2‐C5H4N), 3 ; P(4‐C6H4Cl)3, 4 ; PPh3, 5 ; P(4‐C6H4F)3, 6 ] in 81%–94% yields. Complexes 2 – 6 have been characterized by elemental analysis, spectroscopy, and X‐ray crystallography. In addition, electrochemical studies revealed that these complexes can catalyze the reduction of protons to H2 in the presence of HOAc. 相似文献
14.
Zhong Weizhou Zhang Zexiong Chen Xiaowei Wei Qiang Chen Gang Huang Xicheng 《Acta Mechanica Sinica》2021,37(7):1136-1151
Acta Mechanica Sinica - Multi-scale finite element method is adopted to simulate wood compression behavior under axial and transverse loading. Representative volume elements (RVE) of wood... 相似文献
15.
Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP) receives increasing attention in membrane separation field based on its advantages such as high mechanical strength, thermal and chemical stability. However, controlling the microporous structure is still challenging.In this work, we attempted to tailor the morphology of PVDF-HFP membrane via a one-step reactive vapor induced phase separation method.Namely, PVDF-HFP was dissolved in a volatile solvent and then was cast in an ammonia water vapor atmosphere. After complete evaporation of solvent, membranes with adjustable porous structure were prepared, and the microstructures of the membranes were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction characterizations. Based on the results, a mechanism of dehydrofluorination induced cross-linking of PVDF-HFP has been suggested to understand the morphology tailoring.To our knowledge, this is the first report of one-step reactive vapor induced phase separation strategy to tailor morphology of PVDF-HFP membrane. In addition, the membranes prepared in the ammonia water vapor exhibited enhanced mechanical strength and achieved satisfactory separation efficiency for water-in-oil emulsions, suggesting promising potential. 相似文献
16.
随着化石能源的日益短缺,可再生木质生物质资源的利用越来越受到重视,常压液化技术是生物质资源高效利用的主要方式之一。利用单因素方法,探讨液化温度、复配液化剂二甘醇(DEG)与1,2-丙二醇(PG)的混合比、液固比、催化剂磷酸的用量、反应时间等因素对玉米秸秆液化得率的影响,以便优化其液化工艺;然后采用热重分析仪(TGA)、气相色谱-质谱技术(GC-MS)和核磁共振(NMR)技术对此优化条件下所得生物油的挥发降解特性和主要组成成分进行了检测探讨。分析表明,玉米秸秆液化时优化工艺参数为:液化温度170 ℃,液化剂DEG与PG混合比1∶2,液固比5∶1,H3PO4用量10%,反应时间45 min;此时玉米秸秆液化得率高至99.50%。TGA结果表明,此条件下所得生物油含有80%以上碳数小于25的化合物,热解后最终残炭量约为15%。GC-MS表明,可以检测出此生物油中含有的39种有机物,其中,醇类有机物的含量最多,酚类有机物的含量次之,它们相对含量依次是70.70%和25.63%,其还含有一定量的有机酸(2.80%)、醚类(0.64%)、酯类(0.10%)和酮类(0.13%)等有机物;其组分十分复杂,高含氧量,稳定性较差。1H-和13C-NMR分析表明,不同化学位移δ与生物油中不同类型的质子和碳原子相对应,明确生物油中不同类型H和C的分布,有利于对其分子结构进行深入探讨。这些研究为非木材生物质高效液化条件的选择及液化产物制备化学品和生物燃油给予理论基础与应用支持,促进了生物质资源的有效转化利用及其生物质基产品的开发。 相似文献
17.
We numerically solve the time-dependent Ginzburg–Landau equations for two-gap superconductors using the finite-element technique. The real-time simulation shows that at low magnetic field, the vortices in small-size samples tend to form clusters or other disorder structures. When the sample size is large, stripes appear in the pattern. These results are in good agreement with the previous experimental observations of the intriguing anomalous vortex pattern, providing a reliable theoretical basis for the future applications of multi-gap superconductors. 相似文献
18.
Chang-Chun Ding Shao-Yi Wu Li-Juan Zhang Si-Ying Zhong Xiao-Hong Chen 《Molecular physics》2020,118(3)
Metal organic frameworks (MOFs) have been well-known and extensively researched due to the high storage /good selectivity for gas molecules. Herein, the structures and electron paramagnetic resonance (EPR) spectra for dicopper paddle wheel MOF compound (Cu2(µ2-O2CCH3)4 with various gas molecule are theoretically investigated by density functional theory (DFT) calculations. The adsorption energies and isotherms (including pure gas molecules and the mixed ones) are calculated for the gas molecules interacting with the unsaturated Cu2(µ2-O2CCH3)4. Both quantities exhibit the roughly consistent orders (e.g. H2S?>?NH3?>?CO2?>?CO?>?H2O?>?N2?>?NO?>?H2 for isotherms and H2S?>?NH3?>?N2?>?CO2?>?NO?>?H2O?>?H2?>?CO for adsorption energies), possibly suggesting that this material may act as a potential adsorbent of these gas molecules. The catalytic property of Cu2(µ2-O2CCH3)4 for oxidation of CO and NO into non-toxic molecules and splitting of H2O into H2 and O2 in the solvent condition are uniformly discussed. Simulation of Grand Canonical Monte Carlo (GCMC) in MS 8.0 and calculations in Langmuir model reveal that Cu2(µ2-O2CCH3)4 has good selectivity for CH4 in natural gas (CH4/CO2/N2) and SO2 in fog (SO2/NO/NO2/H2O/O2), which would exhibit potential environmentally friendly applications. 相似文献
19.
Chen Xiao-Lu Li Xiang-Yu Li Shuai-Shuai Bai Xue Li Tao Goud Erukala Yadaiah Zhong Chong-Min Zuo Ya-Jie 《Russian Journal of General Chemistry》2020,90(11):2163-2169
Russian Journal of General Chemistry - The Grubbs–Hoveyda catalysts have a wide range of applications in catalyzed formation of the carbon-carbon double bonds. In this study, several... 相似文献
20.
Nonlinear Dynamics - TheEditor-in-Chief has retracted this article [1] because it overlaps significantly with an 相似文献