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101.
Xiaolan Tong Shan Wang Jun Zuo Yingchong Ge Qiang Gao Suijun Liu Jianhua Ding Fen Liu Jianqiang Luo Jianbo Xiong 《中国化学快报》2021,32(2):604-608
Two new hydrostable two-dimensional(2 D) uranyl coordination complexes [(UO_2)_5(μ_3-O)_2(nbca)_2].7 H_2O(1) and [(UO_2)_3(nbca)_2(H_2O)_3]·2 H_2O(2)(H_3 nbca=5-nitro-1,2,3-benzenetricarboxylic acid) were hydrothermal synthesized.Single-crystal structural refinements reveal that both of the two complexes were formed by the packing of 2D uranyl coordination sheets via the hydrogen bonds.The nbca ligand coordinating to the uranyl polyhedron centers constructed the 2D sheets.There are UO_8 hexagonal bipyramids and UO_7 pentagonal bipyramids in 1 while only U07 pentagonal bipyramids in 2.Photocatalytic degradation of rhodamine B(RhB) in aqueous solution was studied.Complex 2 possesses better performance than 1 with 96.2 % of the RhB was degraded in only 60 min.Mechanism studies reveal that the dissolved oxygens are essential to the RhB degradation.The photocurrent density of 2 is more stable than that of 1,which indicating the stronger ability to separate photoexcited electrons and hole pairs of 2. 相似文献
102.
规模生猪养殖液态生物质资源循环开发仿真分析 总被引:1,自引:0,他引:1
对银河杜仲基于沼气工程的液态生物质资源的循环开发进行仿真分析。根据历史数据和公司五年、十年发展规划,使用基于反馈调控参数的入树逐步建模法,构建7棵入树仿真模型;通过仿真定量揭示公司规划实施过程中将产生大量废弃物类生物质,沼气工程对废弃物开发产生的沼液和沼气中含大量的生物质能;为此,基于仿真结果及系统反馈结构,提出促进消除环境与猪肉产品双污染,实现绿色安全猪肉生产和改善环境双重目标的三条管理对策,并进行初步实施。 相似文献
103.
《Electrochemistry communications》2007,9(4):596-598
Hard carbon spherule (HCS) has been investigated as a counter electrode for dye-sensitized solar cells. The overall conversion efficiency of the cell reached 5.7%, which is comparable to 6.5% of the counter electrode of platinum-sputtered fluorine-doped tin oxide used in Grätzel-type solar cells under the same experimental condition. It is found that the photovoltaic performance was strongly affected by the specific surface areas of the carbon materials. 相似文献
104.
We propose a square-core metallic nanotube array and investigate its optical transmission property theoretically. We find that the transmission spectra can be tuned by the width of square-core edge, the intertube spacing and the dielectric constants of the core and the embedding medium between the nanotubes. We show that there is a band gap over a wide optical wavelength, and its width, number and position are sensitive to the tunable parameters. We also discuss the situation of the rectangular-core nanotube arrays and present that modification of the size of internal holes leads to redshift of the transmission spectra. Based on the localized nature of the field distributions, we show that there are local plasmonic resonant modes that originate from multipolar plasmon polaritons and a large number of opposing surface charges build up in the gap between adjacent nanotubes. 相似文献
105.
《Tetrahedron》2014,70(32):4738-4744
Gram-scale total synthesis of (±)-8-[1-(4′-hydroxy-3′-methoxyphenyl)prop-2-en-1-yl]-galangin (1) and -chrysin (2) has been accomplished in eight steps from commercially available phloroglucinol and three steps from commercially available chrysin, respectively, featuring an efficient introduction of C(8) (1-prop-2-en-1-yl)phenyl moiety in the natural products through chemo- and regioselective cinnamylation and regioselective aromatic Claisen rearrangement. 相似文献
106.
Li-Yun Hu Shi-You Liu Kai-Min Zheng Fang Jia Hong-Yi Fan 《International Journal of Theoretical Physics》2014,53(2):380-389
We find new operator formulas for converting Q?P and P?Q ordering to Weyl ordering, where Q and P are the coordinate and momentum operator. In this way we reveal the essence of operators’ Weyl ordering scheme, e.g., Weyl ordered operator polynomial ${_{:}^{:}}\;Q^{m}P^{n}\;{_{:}^{:}}$ , $$\begin{aligned} {_{:}^{:}}\;Q^{m}P^{n}\;{_{:}^{:}} =&\sum_{l=0}^{\min (m,n)} \biggl( \frac{-i\hbar }{2} \biggr) ^{l}l!\binom{m}{l}\binom{n}{l}Q^{m-l}P^{n-l} \\ =& \biggl( \frac{\hbar }{2} \biggr) ^{ ( m+n ) /2}i^{n}H_{m,n} \biggl( \frac{\sqrt{2}Q}{\sqrt{\hbar }},\frac{-i\sqrt{2}P}{\sqrt{\hbar }} \biggr) \bigg|_{Q_{\mathrm{before}}P} \end{aligned}$$ where ${}_{:}^{:}$ ${}_{:}^{:}$ denotes the Weyl ordering symbol, and H m,n is the two-variable Hermite polynomial. This helps us to know the Weyl ordering more intuitively. 相似文献
107.
Xiaoyu Li Fei Chen Chengjiang Lian Shizheng Zheng Quanhong Hu Shuwang Duo Wenkui Li Changyuan Hu 《Journal of Cluster Science》2016,27(6):1877-1892
Au/TiO2/graphene composite was synthesized by the combination of electrostatic attraction and photo-reduction method. In the composite, graphene sheets act as an adsorption site for dye molecules to provide a high concentration of dye near to the TiO2 and Au nanoparticles (NPs), and work as an excellent electron transporter to separate photoinduced e ?/h + pairs. Under UV irradiation, photogenerated electrons of TiO2 are transferred effectively to Au NPs and graphene sheets, respectively, retarding the recombination of electron–hole pairs. Under visible light irradiation, the Au NPs are photo-excited due to the surface plasmon resonance effect, and charge separation is accomplished by the interfacial electron injection from the Au NPs to the conduction band of TiO2 and then transfer further to graphene sheets. As a result, compared with pure TiO2, Au/TiO2/graphene composite exhibited much higher photocatalytic activity for degradation of methylene blue under both UV and visible light irradiation, based on the synergistic effect of Au, graphene in contact with TiO2, allowing response to the visible light, effective separation of photoinduced charges, and better adsorption of the dye molecules. 相似文献
108.
109.
Reconstruction and interpretation of photon Doppler velocimetry spectrum for ejecta particles from shock-loaded sample in vacuum 下载免费PDF全文
《中国物理 B》2021,30(6):66201-066201
The photon Doppler velocimetry(PDV) spectrum is investigated in an attempt to reveal the particle parameters of ejecta from shock-loaded samples in a vacuum. A GPU-accelerated Monte–Carlo algorithm, which considers the multiplescattering effects of light, is applied to reconstruct the light field of the ejecta and simulate the corresponding PDV spectrum.The influence of the velocity profile, total area mass, and particle size of the ejecta on the simulated spectra is discussed qualitatively. To facilitate a quantitative discussion, a novel theoretical optical model is proposed in which the singlescattering assumption is applied. With this model, the relationships between the particle parameters of ejecta and the peak information of the PDV spectrum are derived, enabling direct extraction of the particle parameters from the PDV spectrum.The values of the ejecta parameters estimated from the experimental spectrum are in good agreement with those measured by a piezoelectric probe. 相似文献
110.
《Tetrahedron: Asymmetry》1998,9(22):4073-4078
The efficient asymmetric protonation of lithium enolates of 2-alkylcycloalkanones (87–96% ee) with readily accessible chiral α-sulfinyl alcohols is described. Optimal stereoselection is achieved for each lithium enolate at a different reaction temperature in the range −40 to −100°C. 相似文献