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991.
Organic electroluminescent diodes with a heterostructure of 9,10-bis(phenylethnyl) anthracene(BPEA) doped poly(N-vinylcarbazole) (PVK)/tris(8-hydroxyquinoline)aluminum (Alq_3) have beenfabricated. The electroluminescence (EL) both from BPEA and Alq_3 were observed when the Alq_3 layer isthin enough. With increasing thickness of the Alq_3 layer, the relative emission intensity of BPEA is graduallydecreased. For the thin Alq_3 layer structure, the light emission of Alq_3 becomes more dominant as the appliedvoltage increases. It is proposed that the electron-hole recombination takes place in both PVK and Alq_3 films.The field-induced quenching theory has also been applied to explain the change of the EL spectra withapplied voltage. 相似文献
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994.
Mi Zhou Dr. Fubao Xing Prof. Meilin Ren Yan Feng Dr. Yongqiang Zhao Dr. Haixia Qiu Prof. Xiaodong Wang Dr. Chunjuan Gao Dr. Feifei Sun Prof. Yongqiang He Dr. Zhiqing Ma Dr. Pu Wen Dr. Jianping Gao Prof. 《Chemphyschem》2009,10(3):523-526
Structural colors: Poly(N‐isopropyl acrylamide) based microgel photonic crystals are fabricated by using a new method called “high‐temperature‐induced hydrophobic assembly”. The assembling conditions affect the water content of the crystals, thus determining their structural color (see image). The obtained photonic crystals are sensitive to solvents, and the reversible changes in their color can be observed with the naked eye.
995.
小孔矩形腔体屏蔽特性的研究 总被引:3,自引:0,他引:3
本文提出了有孔腔体远、近场电磁屏蔽效能的计算方法,体研究了矩形腔体的屏蔽特性,讨论了各类孔对屏蔽能的影响程度。数值结果表明,理论计算与实验数据吻合较好。 相似文献
996.
A dual-washer superconducting quantum interference device(SQUID) with a loop inductance of 350 pH and two onwasher integrated input coils is designed according to conventional niobium technology. In order to obtain a large SQUID flux-to-voltage transfer coefficient, the junction shunt resistance is selected to be 33 ?. A vertical SQUID gradiometer module with a baseline of 100 mm is constructed by utilizing such a SQUID and a first-order niobium wire-wound antenna.The sensitivity of this module reaches about 0.2 fT/(cm·Hz1/2) in the white noise range using a direct readout scheme, i.e.,the SQUID is directly connected to an operational amplifier, in a magnetically shielded room. Some magnetocardiography(MCG) measurements with a sufficiently high signal-to-noise ratio(SNR) are demonstrated. 相似文献
997.
Two new nortriterpenoids, paeonenoides D and E ( 1 and 2 , resp.), together with seven known compounds, were isolated from the roots of Paeonia lactiflora. Their structures were elucidated on the basis of spectroscopic evidence. Compounds 1 – 7 were screened for inhibitory effects against NO production in LPS‐induced RAW246.7 macrophages and for cytotoxic activities against HL‐60, Hep‐G2, and SK‐OV‐3 cell lines. Compounds 1 – 3 and 5 – 7 exhibited inhibitory activities with IC50 values in the range of 9.6–32.2 μM . Triterpenoids with an epoxide ring and a free COOH function, 1 – 3 , showed effectively increased activities compared with other pentacyclic triterpenoids. Compounds 1 – 6 showed significant cytotoxic activities against the Hep‐G2 cell line and modest cytotoxic activities against HL‐60 and SK‐OV‐3 cell lines. 相似文献
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999.
Wanwan Qiu Jenny Gehlen Margherita Bernero Christian Gehre Gian Nutal Schädli Ralph Müller Xiao-Hua Qin 《Advanced functional materials》2023,33(20):2214393
Tomographic volumetric bioprinting (VBP) enables fast photofabrication of cell-laden hydrogel constructs in one step, addressing the limitations of conventional layer-by-layer additive manufacturing. However, existing biomaterials that fulfill the physicochemical requirements of VBP are limited to gelatin-based photoresins of high polymer concentrations. The printed microenvironments are predominantly static and stiff, lacking sufficient capacity to support 3D cell growth. Here a dynamic resin based on thiol–ene photo-clickable polyvinyl alcohol (PVA) and thermo-sensitive sacrificial gelatin for fast VBP of functional ultrasoft cell-laden hydrogel constructs within 7–15 s is reported. Using gelatin allows VBP of permissive hydrogels with low PVA contents of 1.5%, providing a stress-relaxing environment for fast cell spreading, 3D osteogenic differentiation of embedded human mesenchymal stem cells and matrix mineralization. Additionally, site-specific immobilization of molecules-of-interest inside a PVA hydrogel is achieved by 3D tomographic thiol–ene photopatterning. This technique may enable spatiotemporal control of cell-material interactions and guides in vitro tissue formation using programmed cell-friendly light. Altogether, this study introduces a synthetic dynamic photoresin enabling fast VBP of functional ultrasoft hydrogel constructs with well-defined physicochemical properties and high efficiency. 相似文献
1000.
以酰氯,2-硝基亚胺咪唑烷和2-氰基亚胺1,3-噻唑烷为主要原料,设计并合成了5个新型的2-硝基亚氨基咪唑烷(1a~1e)和10个新型的2-氰基亚氨基-1,3-噻唑烷衍生物(2a~2g,3a~3c),其结构经1H NMR和13C NMR表征。初步生物活性测试结果表明,在浓度为20 mg·L-1时,1e和2e对苹果腐烂病菌的抑制率分别为70.69%,80.63%,对葡萄黑豆病菌的抑制率分别为58.87%,62.02%;对苹果腐烂病菌的EC50分别为4.5mg·L-1,8.6 mg·L-1,对葡萄黑豆病菌的EC50分别11.7 mg·L-1,14.3 mg·L-1,优于阳性对照药多菌灵。 相似文献