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排序方式: 共有197条查询结果,搜索用时 31 毫秒
191.
Lei Wang Mingwei Cao Miao Wang Huanhuan Gao Qiong Shi 《International journal of quantum chemistry》2024,124(1):e27254
In order to identify high-performance non-fused ring electron acceptors for bulk heterojunction (BHJ) solar cells, six structurally diverse molecules are designed and categorized into two series. The first series is anchored by R1 as the reference molecule, featured fixed BDT, IC-2F end groups and modified π bridges. The second series is anchored by R2 as the reference molecule, incorporated a terminal IC-2F and a central core modified with EDOT bridge. The electronic structure and photoelectric properties of all acceptor molecules were investigated using density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Charge transfer matrix (CTM), Density of states (DOS) and Reorganization energy (RE) etc. were analyzed to provide fundamental knowledge on charge transport and electronic excitation. Among the studied molecules, W2 exhibited a smaller energy gap (1.74 eV) compared to the other molecules, effectively transferring its electron from HOMO to LUMO. At the same time, the W2 molecule has excellent Voc and FF. Furthermore, W2 displayed the largest λmax redshift compared to R1. Although W3 had a smaller value of λh, the comprehensive photovoltaic parameters of W2 were more excellent. The research results not only demonstrated the feasibility of introducing different alkoxy groups to alter the structure of the π bridge and central core is a feasible method for constructing high-performance NFREAs, but also highlighted that BDT cores combined with EDOT bridges are among the most promising small molecule acceptors (SMAs) that could be considered as reasonable candidates for synthesis and incorporation into organic solar cells. The results of this study are expected to provide seminal ideas for the design of high-performance non-fullerene acceptors. 相似文献
192.
Jie Liu Qian Zhang Yu Huo Mingwei Zhao Dezhi Sun Xilian Wei Shaojie Liu Liqiang Zheng 《Colloid and polymer science》2012,290(17):1721-1730
In the preceding paper of this series, we studied the interactions of copolymers with the ionic liquids, 1-alkyl-3-methylimidazolium bromide (C n mimBr, n?=?8, 10, 12, 14, 16) and N-alkyl-N-methylpyrrolidinium bromide (C n MPB, n?=?12, 14, 16). An obvious difference was detected between the interaction mechanism and the alkyl chain length of the surfactant. In the present study, we performed a systematic study on the interaction of sodium carboxymethylcellulose (NaCMC) with ionic liquids in aqueous solution by isothermal titration microcalorimetry (ITC), conductivity, turbidity, and dynamic light scattering (DLS) measurements. The existence of electrostatic attraction between NaCMC and ILs could increase the complexity of these systems. The results show that the monomers of C8mimBr can bind to the NaCMC chains and form free surfactant micelles in the solution, while no micelle-like C8mimBr/NaCMC cluster is detected. For other surfactants, the formation of surfactant/NaCMC clusters in the solution is driven by electrostatic and hydrophobic interactions, which could be divided into two types. One type is the polymer-induced surfactant/NaCMC complexes that form in the solution for the surfactant of C n mimBr (n?=?10, 12, 14) or C n MPB (n?=?12, 14). The other type is that the surfactant-induced surfactant/NaCMC complexes come into being for the surfactant of C16mimBr or C16MPB. Finally, the different modes of complex formation proposed have a good interpretation of the experiment results, unraveling the details of the effect of surfactant alkyl chain length and headgroup on the surfactant–NaCMC interactions. 相似文献
193.
Measuring the thermophysical properties of porous fibrous materials with a new unsteady-state method
In this article, the authors first introduced a theoretical model dealing with unsteady-state heat conduction in porous fabric
to assess the effects due to local convection during the testing. A few important issues are analyzed including the criterion
for local thermal equilibrium in the fibrous materials and the confidence time region (t
min–t
max) during measuring process. The influence due to different heat source capacities can be ignored if the measuring time is
greater than the minimum time duration t
min
, yet the heat loss via outside surface becomes negligible if the testing duration is below the maximum allowable value t
max. Accordingly an apparatus that can simultaneously measure two thermophysical properties (the thermal conductivity k and thermal diffusivity a) of fibrous materials is developed in this study, which then leads to the determination of the volumetric capacity via ρC = k/a. In order to minimize the influence of potential local micro heat convection and the contact resistance during heat transfer,
some background, and stacking materials are adopted in the apparatus. The error range of the apparatus is estimated empirically
based on the data from measuring some Perspex samples. Finally four kinds of polyester nonwoven fabrics with different porosities
are tested using the device and the data analyzed and compared with theoretical predictions. 相似文献
194.
Zhu M Li Y Meng T Zhan P Sun J Wu J Wang Z Zhu S Ming N 《Langmuir : the ACS journal of surfaces and colloids》2006,22(17):7248-7253
A double template-assisted fabrication method for making surface patterns with tunable lattice geometries on a polymer surface is reported. This technique is based on a locally nonuniform strain produced in a double-templated polymer film that has a strong modulation in thickness. It can produce all 2D primitive Bravais lattices as well as chains on the surface of a polymer. The lattice parameters are controllable with nanoprecision by varying the direction and amount of the applied strain. 相似文献
195.
Qinqin Zhang Jingang Wang Mingwei Wang Jing Bu Siwei Zhu Bruce Z. Gao Xiaocong Yuan 《Optics & Laser Technology》2012,44(7):2140-2144
We propose a new parameter w for optimization of foci distribution of conventional fractal zone plates (FZPs) with a greater depth of focus (DOF) in imaging. Numerical simulations of DOF distribution on axis directions indicate that the values of DOF can be extended by a factor of 1.5 or more by a modified quasi-FZP. In experiments, we employ a simple object–lens–image-plane arrangement to pick up images at various positions within the DOF of a conventional FZP and a quasi-FZP, respectively. Experimental results show that the parameter w improves foci distribution of FZPs in good agreement with theoretical predictions. 相似文献
196.
A monolithic 1645 nm Er:YAG nonplanar ring oscillator (NPRO) resonantly pumped by a 1532 nm fiber laser is demonstrated. For reducing the energy-transfer upconversion effect, a 0.5% doped Er:YAG nonplanar crystal was used. An up to 6.1 W single frequency laser output at 1645 nm was obtained, with a slope efficiency of 55.2% and an optical efficiency of 48.0%. The linewidth of the Er:YAG NPRO was 14.4 kHz. 相似文献
197.
Mayur J. Patil Yongming Huang Mingwei Yu Xinzhong Dong Bradley J. Undem Shaoyong Yu 《Molecules (Basel, Switzerland)》2022,27(21)
Chemotherapeutic agent-induced nausea and vomiting are the severe adverse effects that are induced by their stimulations on the peripheral and/or central emetic nerve pathways. Even though ginger has been widely used as an herbal medicine to treat emesis, mechanisms underlying its neuronal actions are still less clear. The present study aimed to determine the chemotherapeutic agent vincristine-induced effect on gastroesophageal vagal afferent nerve endings and the potential inhibitory role of ginger constituent 6-shogaol on such response. Two-photon neuron imaging studies were performed in ex vivo gastroesophageal-vagal preparations from Pirt-GCaMP6 transgenic mice. Vincristine was applied to the gastroesophageal vagal afferent nerve endings, and the evoked calcium influxes in their intact nodose ganglion neuron somas were recorded. The responsive nodose neuron population was first characterized, and the inhibitory effects of 5-HT3 antagonist palonosetron, TRPA1 antagonist HC-030031, and ginger constituent 6-shogaol were then determined. Vincristine application at gastroesophageal vagal afferent nerve endings elicited intensive calcium influxes in a sub-population of vagal ganglion neurons. These neurons were characterized by their positive responses to P2X2/3 receptor agonist α,β-methylene ATP and TRPA1 agonist cinnamaldehyde, suggesting their nociceptive placodal nodose C-fiber neuron lineages. Pretreatment with TRPA1 selective blocker HC-030031 inhibited vincristine-induced calcium influxes in gastroesophageal nodose C-fiber neurons, indicating that TRPA1 played a functional role in mediating vincristine-induced activation response. Such inhibitory effect was comparable to that from 5-HT3 receptor antagonist palonosetron. Alternatively, pretreatment with ginger constituent 6-shogaol significantly attenuated vincristine-induced activation response. The present study provides new evidence that chemotherapeutic agent vincristine directly activates vagal nodose nociceptive C-fiber neurons at their peripheral nerve endings in the upper gastrointestinal tract. This activation response requires both TRPA1 and 5-HT3 receptors and can be attenuated by ginger constituent 6-shogaol. 相似文献