排序方式: 共有59条查询结果,搜索用时 15 毫秒
21.
Giribabu L Bessho T Srinivasu M Vijaykumar C Soujanya Y Reddy VG Reddy PY Yum JH Grätzel M Nazeeruddin MK 《Dalton transactions (Cambridge, England : 2003)》2011,40(17):4497-4504
Two new heteroleptic ruthenium(II) photosensitizers that contains 2,2';6,2'-terpyridine with extended π-conjugation with donor groups, a 4,4'-dicarboxylic acid-2,2'-bipyridine anchoring ligand and a thiocyanate ligand have been designed, synthesized and fully characterized by CHN, mass spectrometry, UV-vis and fluorescence spectroscopies and cyclic voltammetry. The new sensitizers have either 3,5-di-tert-butyl phenyl (m-BL-5) or triphenylamine (m-BL-6) groups, where the molar extinction coefficient of both the sensitizers is higher than the analogous ruthenium dyes. Both the sensitizers were tested in dye-sensitized solar cells using two different redox electrolytes. 相似文献
22.
Baranoff E Jung I Scopelliti R Solari E Grätzel M Nazeeruddin MK 《Dalton transactions (Cambridge, England : 2003)》2011,40(26):6860-6867
A library of emission spectra of 90 bis-cyclometallated iridium complexes has been obtained using a simple combinatorial approach performed at room temperature. Trends in emission maxima are rationalized using Hammett parameters and invoking inter ligand energy transfer (ILET) processes. The screening approach allowed us to observe trends in the broadness of emission spectra opening the way for a rational approach to the engineering of the emission colour purity at a molecular level. Finally limitations to the screening strategy are discussed using a case study that involves two different monodentate ligands. 相似文献
23.
Dobhal MP Li G Gryshuk A Graham A Bhatanager AK Khaja SD Joshi YC Sharma MC Oseroff A Pandey RK 《The Journal of organic chemistry》2004,69(19):6165-6172
Plumieride was isolated as one of the major components from the biologically active methanolic extract of the bark of Plumeria bicolor (family Apocynaceae). For investigating the effect of substituents on cytotoxic activity it was modified into a series of compounds. Replacing the methyl ester functionality of plumieride with alkyl amides of variable carbon units improved the cytotoxic activity, and a correlation between overall lipophilicity and cytotoxic activity was observed. In plumieride, the glucose moiety was converted into a di- and trisaccharide by following the protection and deprotection approach, and the resulting compounds produced enhanced cytotoxicity. However, these compounds were found to be less effective than plumeiride containing a dodecyl (12 carbon units) amide group. Among all of the derivatives, the naturally occurring plumieride showed the least cytotoxicity (50% cell kill = 49.5 microg/mL), and the dodecyl amide analogue of plumieridepentaacetate produced the best efficacy (50% cell kill = 11.8 microg/mL). The di- and trisaccharide analogues were found to be slightly less effective than the dodecyl derivative (50% cell kill = 15-17 microg/mL). The in vitro cytotoxicity of the plumieride analogues was determined in radiation-induced fibrosarcoma (RIF) tumor cells. 相似文献
24.
Ruiyuan Hu Chuangye Ge Liang Chu Yifei Feng Shanshan Xiao Yuhui Ma Wei Liu Xing'ao Li Mohammad Khaja Nazeeruddin 《Journal of Energy Chemistry》2021,(8):581-588
Organometallic halide perovskite materials make great achievements in optoelectronic fields,especially in solar cells,in which the organic cations contain amine... 相似文献
25.
Lara Tejerina Dr. M. Victoria Martínez‐Díaz Prof. Dr. Mohammad Khaja Nazeeruddin Prof. Tomas Torres 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4369-4373
Phthalocyanines (Pcs) are used as sensitizers in dye‐sensitized solar cells (DSSCs) because of their stability and intense absorption in the red and near‐IR regions. Impressive progress has been made in photovoltaic efficiencies by introduction of bulky peripheral substituents to help suppress macrocycle aggregation. To reach benchmark efficiencies reported for other related dyes, new designs need to be explored. Single carboxy‐ZnPc regioisomers substituted at the non‐peripheral positions by rigid aryl groups have now been studied, which has shed light on the influence of steric hindrance and/or orientation of the substituent around the anchoring group on the photovoltaic response. The regioisomer bearing the aryl group far away from the anchoring group produces a more effective sensitization of the TiO2 films and higher short‐circuit photocurrent density (Jsc). Taking advantage of the good photovoltaic performance in the near‐IR region of this ZnPc, it was combined with another appropriate dye for panchromatic sensitization of the mesoporous photoelectrode and an increase of the overall device efficiency. 相似文献
26.
The ability to determine the individual components of displacement, strain and stress from measured values of a single component of displacement is demonstrated. Advantages of the method include its ability to significantly simplify the experimental technique by measuring only a single displacement component, to provide reliable results both full-field and at the edge of geometric discontinuities, and the lack of need to differentiate the recorded data physically. Results agree with those from thermoelastic stress analysis, strain gages and finite element analysis. 相似文献
27.
Dr. Agustín Molina‐Ontoria Dr. Iwan Zimmermann Inés Garcia‐Benito Paul Gratia Dr. Cristina Roldán‐Carmona Sadig Aghazada Prof. Dr. Michael Graetzel Prof. Dr. Mohammad Khaja Nazeeruddin Prof. Dr. Nazario Martín 《Angewandte Chemie (International ed. in English)》2016,55(21):6270-6274
New star‐shaped benzotrithiophene (BTT)‐based hole‐transporting materials (HTM) BTT‐1, BTT‐2 and BTT‐3 have been obtained through a facile synthetic route by crosslinking triarylamine‐based donor groups with a benzotrithiophene (BTT) core. The BTT HTMs were tested on solution‐processed lead trihalide perovskite‐based solar cells. Power conversion efficiencies in the range of 16 % to 18.2 % were achieved under AM 1.5 sun with the three derivatives. These values are comparable to those obtained with today's most commonly used HTM spiro‐OMeTAD, which point them out as promising candidates to be used as readily available and cost‐effective alternatives in perovskite solar cells (PSCs). 相似文献
28.
Xuepeng Liu Bin Ding Mingyuan Han Zhenhai Yang Jianlin Chen Pengju Shi Xiangying Xue Rahim Ghadari Xianfu Zhang Rui Wang Keith Brooks Li Tao Sachin Kinge Songyuan Dai Jiang Sheng Paul J. Dyson Mohammad Khaja Nazeeruddin Yong Ding 《Angewandte Chemie (International ed. in English)》2023,62(29):e202304350
Hole transport materials (HTMs) are a key component of perovskite solar cells (PSCs). The small molecular 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl)-amine-9,9′-spirobifluorene (spiro-OMeTAD, termed “Spiro”) is the most successful HTM used in PSCs, but its versatility is imperfect. To improve its performance, we developed a novel spiro-type HTM (termed “DP”) by substituting four anisole units on Spiro with 4-methoxybiphenyl moieties. By extending the π-conjugation of Spiro in this way, the HOMO level of the HTM matches well with the perovskite valence band, enhancing hole mobility and increasing the glass transition temperature. DP-based PSC achieves high power conversion efficiencies (PCEs) of 25.24 % for small-area (0.06 cm2) devices and 21.86 % for modules (designated area of 27.56 cm2), along with the certified efficiency of 21.78 % on a designated area of 27.86 cm2. The encapsulated DP-based devices maintain 95.1 % of the initial performance under ISOS-L-1 conditions after 2560 hours and 87 % at the ISOS-L-3 conditions over 600 hours. 相似文献
29.
S.-J. Lin S. Quinn D. R. Matthys A. M. New I. M. Kincaid B. R. Boyce A. A. Khaja R. E. Rowlands 《Experimental Mechanics》2011,51(6):797-814
Thermoelastic data are combined with an Airy stress function to determine the individual stresses on and near the boundary
of a circular hole which is located below a concentrated edge-load in a plate. Coefficients of the stress function are evaluated
from the measured temperatures and the local traction-free conditions are satisfied by imposing srr = trq = 0 {\sigma_{r{\rm{r}}}} = {\tau_{r\theta }} = 0 analytically on the edge of the hole. The latter has the advantage of reducing the number of coefficients in the stress function
series. The method simultaneously smoothes the measured input data, satisfies the local boundary conditions and evaluates
individual stresses on, and in the neighbourhood of, the edge of the hole. Attention is paid to how many coefficients to retain
in the stress function series. Although the presence of high stress concentration factors, together with a hole-diameter-to-plate-thickness
ratio of only two, result in some three-dimensional effects, these are relatively small and the agreement between the thermoelastic
values, those from recorded strains and FEM-predicted surface stresses is good. 相似文献
30.
Juveriya Farooq Rokeya Sultana Tahreen Taj Syed Mohammed Basheeruddin Asdaq Abdulkhaliq J. Alsalman Mohammed Al Mohaini Maitham A. Al Hawaj Mehnaz Kamal Saad Alghamdi Mohd. Imran Haleema Shahin Ruheena Tabassum 《Molecules (Basel, Switzerland)》2022,27(1)
The drugs used to treat cancer not only kill fast-growing cancer cells, but also kill or slow the growth of healthy cells, causing systemic toxicities that lead to altered functioning of normal cells. Most chemotherapeutic agents have serious toxicities associated with their use, necessitating extreme caution and attention. There is a growing interest in herbal remedies because of their pharmacological activities, minimal side effects, and low cost. Thymoquinone, a major component of the volatile oil of Nigella sativa Linn, also known as black cumin or black seeds, is commonly used in Middle Eastern countries as a condiment. It is also utilized for medicinal purposes and possesses antidiabetic, anti-cancer, anti-inflammatory, hepatoprotective, anti-microbial, immunomodulatory, and antioxidant properties. This review attempts to compile the published literature demonstrating thymoquinone’s protective effect against chemotherapeutic drug-induced toxicities. 相似文献