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191.
Semiconducting Polymer Nanoparticles as Fluorescent Probes for Biological Imaging and Sensing 下载免费PDF全文
In recent years, semiconducting polymer nanoparticles have emerged as a new class of extraordinarily bright fluorescent probes. These polymer nanoparticles, which are primarily composed of π‐conjugated polymers, exhibit a variety of outstanding features, including exceptional fluorescence brightness, fast radiative rate, good photostability, facile surface functionalization, and low cytotoxicity. These advantageous characteristics make polymer nanoparticles highly promising for applications in biological imaging and sensing. This progress report highlights recent advances in the synthesis, characterization, and applications as bio‐labels or sensors of these highly emissive organic nanoparticles. 相似文献
192.
Jrmie Loulier Franois Lefort Marcin Stocki Monika Asztemborska Rafa Szmigielski Krzysztof Siwek Tomasz Grzywacz Tom Hsiang Sawomir
lusarski Tomasz Oszako Marcin Klisz Rafa Tarakowski Justyna Anna Nowakowska 《Molecules (Basel, Switzerland)》2020,25(23)
Fungi and oomycetes release volatiles into their environment which could be used for olfactory detection and identification of these organisms by electronic-nose (e-nose). The aim of this study was to survey volatile compound emission using an e-nose device and to identify released molecules through solid phase microextraction–gas chromatography/mass spectrometry (SPME–GC/MS) analysis to ultimately develop a detection system for fungi and fungi-like organisms. To this end, cultures of eight fungi (Armillaria gallica, Armillaria ostoyae, Fusarium avenaceum, Fusarium culmorum, Fusarium oxysporum, Fusarium poae, Rhizoctonia solani, Trichoderma asperellum) and four oomycetes (Phytophthora cactorum, P. cinnamomi, P. plurivora, P. ramorum) were tested with the e-nose system and investigated by means of SPME-GC/MS. Strains of F. poae, R. solani and T. asperellum appeared to be the most odoriferous. All investigated fungal species (except R. solani) produced sesquiterpenes in variable amounts, in contrast to the tested oomycetes strains. Other molecules such as aliphatic hydrocarbons, alcohols, aldehydes, esters and benzene derivatives were found in all samples. The results suggested that the major differences between respective VOC emission ranges of the tested species lie in sesquiterpene production, with fungi emitting some while oomycetes released none or smaller amounts of such molecules. Our e-nose system could discriminate between the odors emitted by P. ramorum, F. poae, T. asperellum and R. solani, which accounted for over 88% of the PCA variance. These preliminary results of fungal and oomycete detection make the e-nose device suitable for further sensor design as a potential tool for forest managers, other plant managers, as well as regulatory agencies such as quarantine services. 相似文献
193.
Ren‐Jang Wu Mei‐Yun Chen Bing‐Huan Hsien Hsiang‐Ning Luk Murthy Chavali 《中国化学会会志》2014,61(12):1365-1370
A novel method of measuring the concentration of the local anesthetic ropivacaine drip bags used in hospi‐ tals was developed using electrochemical impedance technique. Polypyrrole (Ppy)/graphene oxide (GO) composites were prepared by electrochemically polymerization over Au electrodes, which served as working electrodes. The Ppy/GO composite electrodes were characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Various concentrations of ropivacaine (0.1–20 ppm) were prepared in a sample drip bag solution of 0.9 % NaCl from hostpital. The composite Ppy/1 % GO electrode exhibited strongest linearity (R2=0.960) than the Ppy electrode (R2=0.928) at a frequency of 100 kHz. The detection limits of ropivacaine on Ppy and Ppy/1 % GO were calculated as 0.11 ppm and 0.08 ppm, respectively. The proposed system yielded response and recovery times under 1 sec detecting 0.1 ppm (100 g/L) of ropivacaine; thus, the proposed online method is promising for measuring ropivacaine concentrations in drip bags. Molecular simulations and equivalent circuits were applied to explain the dynamic behavior of ropivacaine detection system using Ppy and Ppy/GO materials. 相似文献
194.
Lewis Base Assisted Magnesium Complexes Incorporating Pyrrolyl and Ketiminate Ligands: Synthesis,Structural Diversity and Characterization 下载免费PDF全文
Li‐Feng Hsueh Min‐Hui Hsieh Shu‐Ya Hsu Cheng‐Yuan Lee Hsiang‐Hua Hsieh Amitabha Datta Jui‐Hsien Huang Chia‐Her Lin Ting‐Yu Lee 《中国化学会会志》2014,61(8):953-959
A series of four, five and six‐coordinated magnesium derivatives integrating with substituted pyrrole and ketimine ligands are conveniently synthesized. Reaction of two equiv of 2‐dimethylaminomethyl pyrrole with Mg[N(SiMe3)2]2 in THF affords the monomeric magnesium complex Mg[C4H3N(2‐CH2NMe2)]2 (THF)2 ( 1 ) in high yield along with elimination of two equiv of HN(SiMe3)2. Similarly, the reaction between two equiv of 2‐t‐butylaminomethyl pyrrole and Mg[N(SiMe3)2]2 in THF renders the magnesium derivative, Mg[C4H3N(2‐CH2NHtBu)]2(THF)22( 2 ) in good yield. Interestingly, reaction between two equiv of 2‐t‐butylaminomethyl pyrrole and Mg[N(SiMe3)2]2 in toluene, instead of THF, generates Mg[C4H3N(2‐CH2NHtBu)]2 ( 3 ), also in high yield. Furthermore, the assembly of two equiv of ketimine ligand, HOCMeCHCMeNAr (Ar = C6H3‐2,6‐iPr2) and Mg[N(SiMe3)2]2, yields five‐coordinated magnesium derivatives, Mg(OCMeCHCMeNAr)2(THF) ( 4 ) and Mg(OCMeCHCMeNAr)2(OEt2) ( 5 ), using THF and diethyl ether, respectively. All the aforementioned derivatives are characterized by 1H and 13C NMR spectroscopy as well as 1 , 3 , 4 and 5 are subjected to X‐ray diffraction analysis in solid state. 相似文献
195.
Yang Wu Wen‐Zhen Wang Rayyat Huseyn Ismayilov Gene‐Hsiang Lee Shie‐Ming Peng 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(3):285-288
The title compound, catena‐poly[[[diaqua(methanol‐κO)copper(II)]‐μ‐N‐(4‐methylpyrimidin‐2‐yl‐κN1)pyrazin‐2‐amine‐κ2N1:N4] [[aqua(aqua/methanol‐κO)(perchlorato‐κO)copper(II)]‐μ‐N‐(4‐methylpyrimidin‐2‐yl‐κN1)pyrazin‐2‐amine‐κ2N1:N4] tris(perchlorate) methanol monosolvate 1.419‐hydrate], {[Cu(C9H9N5)(CH3OH)(H2O)2][Cu(C9H9N5)(ClO4)(CH3OH)0.581(H2O)1.419](ClO4)3·CH3OH·1.419H2O}n, is a one‐dimensional straight‐chain polymer of N‐(4‐methylpyrimidin‐2‐yl)pyrazin‐2‐amine (L) with Cu(ClO4)2. The complex consists of two crystallographically independent one‐dimensional chains in which the CuII atoms exhibit two different octahedral coordination geometries. The L ligand coordinates to two CuII centres in a tridentate manner, with the pyrazine ring acting as a bridge linking the CuII coordination units and building an infinite one‐dimensional chain. Extensive hydrogen bonding among perchlorate anions, water molecules and L ligands results in three‐dimensional networks. 相似文献
196.
197.
Kellen Chen Yi‐Ming Cheng Dr. Yun Chi Prof. Mei‐Lin Ho Chin‐Hung Lai Pi‐Tai Chou Prof. Shie‐Ming Peng Prof. Gene‐Hsiang Lee 《化学:亚洲杂志》2007,2(1):155-163
We have prepared and characterized a series of osmium complexes [Os2(CO)4(fpbpy)2] ( 1 ), [Os(CO)(fpbpy)2] ( 2 ), and [Os(fpbpy)2] ( 3 ) with tridentate 6‐pyrazol‐3‐yl 2,2′‐bipyridine chelating ligands. Upon the transformation of complex 2 into 3 through the elimination of the CO ligand, an extremely large change in the phosphorescence wavelength from 655 to 935 nm was observed. The results are rationalized qualitatively by the strong π‐accepting character of CO, which lowers the energy of the osmium dπ orbital, in combination with the lower degree of π conjugation in 2 owing to the absence of one possible pyridine‐binding site. As a result, the energy gap for both intraligand π–π* charge transfer (ILCT) and metal‐to‐ligand charge transfer (MLCT) is significantly greater in 2 . Firm support for this explanation was also provided by the time‐dependent DFT approach, the results of which led to the conclusion that the S0→T1 transition mainly involves MLCT between the osmium center and bipyridine in combination with pyrazolate‐to‐bipyridine 3π–π* ILCT. The relatively weak near‐infrared emission can be rationalized tentatively by the energy‐gap law, according to which the radiationless deactivation may be governed by certain low‐frequency motions with a high density of states. The information provided should allow the successful design of other emissive tridentate metal complexes, the physical properties of which could be significantly different from those of complexes with only a bidentate chromophore. 相似文献
198.
199.
Chi‐Wei Tu Ken‐Yen Liu An‐Ting Chien Ming‐Huei Yen Ting Hsiang Weng Kuo‐Chuan Ho King‐Fu Lin 《Journal of polymer science. Part A, Polymer chemistry》2008,46(1):47-53
Poly(n‐isopropylacrylamide) (PNIPAAm) and its nanocomposite with exfoliated montmorillonite (MMT) were prepared by soap‐free emulsion polymerization and individually applied to gel the electrolyte systems for the dye‐sensitized solar cells (DSSCs). Each exfoliated MMT nanoplatelet had a thickness of ~ 1 nm, carried ~ 1.8 cation/nm2, and acted like a two‐dimensional electrolyte. The DSSC with the LiI/I2/tertiary butylpyridine electrolyte system gelled by this polymer nanocomposite had higher short‐circuit current density (Jsc) compared to that gelled by the neat PNIPAAm. The former has a Jsc of 12.6 mA/cm2, an open circuit voltage (Voc) of 0.73 V, and a fill factor (FF) of 0.59, which harvested 5.4% electricity conversion efficiency (η) under AM 1.5 irradiation at 100 mW/cm2, whereas the latter has Jsc = 7.28 mA/cm2, Voc = 0.72 V, FF = 0.60, and η = 3.17%. IPCE of the nanocomposite‐gelled DSSC were also improved. Electrochemical impedance spectroscopy of the DSSCs revealed that the nanocomposite‐gelled electrolytes significantly decreased the impedances in three major electric current paths of DSSCs, that is, the resistance of electrolytes and electric contacts, impedance across the electrolytes/dye‐coated TiO2 interface, and Nernstian diffusion within the electrolytes. The results were also consistent with the increased molar conductivity of nanocomposite‐gelled electrolytes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 47–53, 2008 相似文献
200.