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991.
Photovoltaic and spectral properties of tetraphenyloporphyrin and metallotetraphenyloporphyrin dyes 总被引:1,自引:0,他引:1
Spectroscopical properties and photocurrent (or photovoltage) of tetraphenyloporphyrins and metallotetraphenyloporphyrins in nematic liquid crystal have been studied. Photoelectric response has been measured in an electrochemical cell made of the semitransparent semiconducting and golden electrodes with porphyrin dyes embedded in liquid crystal. Fluorescence, time-resolved luminescence in microsecond time scale and photoacoustic spectra have also been measured. The competition between radiative, non-radiative processes and charge transfer is discussed. It has been shown that effectivity of porphyrins for photocurrent generation depends on the presence/absence of central metal in the macrocycle of porphyrin skeleton and the kind of metal. The schematic model of the contributions of the dye molecule and semiconducting electrode in the electron transfer process is shown. 相似文献
992.
993.
994.
Total syntheses of the peptide enamide natural products terpeptin and aspergillamides A and B are reported. An oxidative decarboxylation-elimination protocol is employed to construct the indolic enamide moiety. Unambiguous stereochemical assignment of (−)-terpeptin is accomplished by synthesis of all possible stereochemical analogues. Select compounds have been evaluated in cell cycle inhibitor assays which show that the natural amino acid configuration of terpeptin has the most potent inhibitory activity. 相似文献
995.
采用电化学方法首先在ITO导电玻璃上制备了一维有序ZnO纳米管阵列,然后在ZnO纳米管阵列上采用电化学方法沉积纳米枝状CdTe,形成了纳米枝状CdTe包覆ZnO纳米管的CdTe@ZnO壳核式复合结构,最后在上述复合结构中旋涂一层P3HT薄膜形成P3HT包覆的P3HT@CdTe@ZnO复合薄膜. 以此复合薄膜为光活性层组装成半导体敏化太阳电池,研究了该类电池的光电转换性能,对该电池的工作原理进行初步研究,所得太阳电池能量转换效率最高达到1.38%. 相似文献
996.
Molecular Parameters and Transmembrane Transport Mechanism of Imidazolium‐Functionalized Binols 下载免费PDF全文
Dr. Marc Vidal Prof. Dr. Andreea Schmitzer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9998-10004
We describe the molecular parameters governing the transmembrane activity of imidazolium‐functionalized anion transporters and present a detailed mechanistic study. These ionophores adopt a mobile‐carrier mechanism for short methyl and butyl chains, a combined mobile‐carrier/transmembrane‐pore mechanism for octyl and dodecyl chains, and form transmembrane aggregates for hexadecyl chains. 相似文献
997.
Tailoring 3,3′‐Dihydroxyisorenieratene to Hydroxystilbene: Finding a Resveratrol Analogue with Increased Antiproliferation Activity and Cell Selectivity 下载免费PDF全文
Yan‐Fei Kang Wen‐Jing Yan Ting‐Wen Zhou Dr. Fang Dai Dr. Xiu‐Zhuang Li Xia‐Zhen Bao Yu‐Ting Du Cui‐Hong Yuan Hai‐Bo Wang Xiao‐Rong Ren Dr. Qiang Liu Dr. Xiao‐Ling Jin Prof. Dr. Bo Zhou Prof. Dr. Jie Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):8904-8908
Four novel compounds were designed by “tailoring” 3,3′‐dihydroxyisorenieratene (a natural carotenoid) based on an isoprene unit retention truncation strategy. Among them, the smallest molecule 1 (2,3,6,2′,3′,6′‐hexamethyl‐4,4′‐dihydroxy‐trans‐stilbene) was concisely synthesized in a one‐pot Stille–Heck tandem sequence, and surfaced as a promising lead molecule in terms of its selective antiproliferative activity mediated by blocking the NCI‐H460 cell cycle in G1 phase. Additionally, theoretical calculations and cell uptake experiments indicate that the unique polymethylation pattern of compound 1 significantly induces a conformational change shift out of planarity and increases its cell uptake and metabolic stability. The observation should be helpful to rationally design resveratrol‐inspired antiproliferative agents. 相似文献
998.
Alternating Current Electrohydrodynamics Induced Nanoshearing and Fluid Micromixing for Specific Capture of Cancer Cells 下载免费PDF全文
Ramanathan Vaidyanathan Dr. Sakandar Rauf Dr. Eloïse Dray Dr. Muhammad J. A. Shiddiky Prof. Matt Trau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3724-3729
We report a new tuneable alternating current (ac) electrohydrodynamics (ac‐EHD) force referred to as “nanoshearing” which involves fluid flow generated within a few nanometers of an electrode surface. This force can be externally tuned via manipulating the applied ac‐EHD field strength. The ability to manipulate ac‐EHD induced forces and concomitant fluid micromixing can enhance fluid transport within the capture domain of the channel (e.g., transport of analytes and hence increase target–sensor interactions). This also provides a new capability to preferentially select strongly bound analytes over nonspecifically bound cells and molecules. To demonstrate the utility and versatility of nanoshearing phenomenon to specifically capture cancer cells, we present proof‐of‐concept data in lysed blood using two microfluidic devices containing a long array of asymmetric planar electrode pairs. Under the optimal experimental conditions, we achieved high capture efficiency (e.g., approximately 90 %; % RSD=2, n=3) with a 10‐fold reduction in nonspecific adsorption of non‐target cells for the detection of whole cells expressing Human Epidermal Growth Factor Receptor 2 (HER2). We believe that our ac‐EHD devices and the use of tuneable nanoshearing phenomenon may find relevance in a wide variety of biological and medical applications. 相似文献
999.
Electrophoresis 2014, 35, 1504–1508. DOI: 10.1002/elps.201400001 Combination of DNA biobarcode assay with micro‐capillary electrophoretic analysis on a chip allows us to perform breast and colorectal cancer cell detection with high sensitivity, multiplexity, and accuracy.
1000.
MnO2‐Modified Persistent Luminescence Nanoparticles for Detection and Imaging of Glutathione in Living Cells and In Vivo 下载免费PDF全文
Dr. Na Li Wei Diao Yaoyao Han Dr. Wei Pan Tingting Zhang Prof. Bo Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(50):16488-16491
Persistent luminescence nanoparticles (PLNPs) hold great promise for the detection and imaging of biomolecules. Herein, we have demonstrated a novel nanoprobe, based on the manganese dioxide (MnO2)‐modified PLNPs, that can detect and image glutathione in living cells and in vivo. The persistent luminescence of the PLNPs can be efficiently quenched by the MnO2 nanosheets. In the presence of glutathione (GSH), MnO2 was reduced to Mn2+ and the luminescence of PLNPs can be restored. The persistent luminescence property can allow detection and imaging without external excitation and avoid the background noise originating from the in situ excitation. This strategy can offer a promising platform for detection and imaging of reactive species in living cells or in vivo. 相似文献