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131.
Giulia Grancini R. Sai Santosh Kumar Agnese Abrusci Hin‐Lap Yip Chang‐Zhi Li Alex‐K. Y. Jen Guglielmo Lanzani Henry J. Snaith 《Advanced functional materials》2012,22(10):2160-2166
Hybrid solar cells based on light absorbing semiconducting polymers infiltrated in nanocrystalline TiO2 electrodes, have emerged as an attractive concept, combining benefits of both low material and processing costs with well controlled nano‐scale morphology. However, after over ten years of research effort, power conversion efficiencies remain around 0.5%. Here, a spectroscopic and device based investigation is presented, which leads to a new optimization route where by functionalization of the TiO2 surface with a molecular electron acceptor promotes photoinduced electron transfer from a low‐band gap polymer(poly[2,6‐(4,4‐bis‐(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b0]dithiophene)‐alt‐4,7‐(2,1,3‐benzothiadia‐zole)] (PCPDTBT) to the metal oxide. This boosts the infrared response and the power conversion efficiency to over 1%. As a further step, by “co‐functionalizing” the TiO2 surface with the electron acceptor and an organic dye‐sensitizer, panchromatic spectral photoresponse is achieved in the visible to near‐IR region. This novel architecture at the heterojunction opens new material design possibilities and represents an exciting route forward for hybrid photovoltaics. 相似文献
132.
This article describes a glove box adaptation of an atomic absorption spectrometer with a graphite furnace as the atomization source. Unlike flame atomic absorption, in which the ground state atoms quickly diffuse out of the atom cell, graphite furnace atomic absorption, being a total consumption technique, offers the ability to de-solvate and atomize the entire sample solution in a more controlled environment. This significantly improves the sensitivity and provides superior detection limits with microliter sample volumes. An atomic absorption instrument was converted into separate modular units consisting of the source, atomizer, and detection system. In addition, these units were modified to enable their use in the glove box, allowing the analysis of nuclear samples. Proper optical alignment of the source, atomizer, and detector system was performed to allow the analysis of toxic samples. 相似文献
133.
Santosh Shrestha 《Progress in Photovoltaics: Research and Applications》2014,22(1):147-149
In order to help keep readers up to date in the field, each issue of Progress in Photovoltaics will contain a list of recently published journal articles most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Transactions on Electron Devices, Journal of Applied Physics, Applied Physics Letters, Progress in Photovoltaics and Solar Energy Materials and Solar Cells. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions, please email Santosh Shrestha at s.shrestha@unsw.edu.au. 相似文献
134.
The physicochemical and interfacial properties of the monomeric surfactants cetyltrimethyl ammonium bromide (CTAB), cetyltriphenyl
phosphonium bromide (CTPB), tetradecyl triphenyl phosphonium bromide (TTPB), cetyldiethylethanol ammonium bromide (CDEEAB),
cetyltrimethyl ammonium chloride (CTACl), tetradecyltrimethyl ammonium bromide (TTAB), and a gemini surfactant (C16-3-C16, 2Br−) at different pH (3.1, 7.0, and 7.75) have been investigated by conductivity and surface tension measurements at 300 K. The
critical micellar concentration (CMC), degree of micellar ionization (α), surface excess concentration (Гmax), minimum surface area per molecule of surfactant (A
min), Gibbs free energy of micellization (∆G
m0), surface pressure at the CMC (π
CMC), and the Gibbs energy of adsorption (∆G
ads0) of the monomeric surfactants have also been determined. The CMC, α and Гmax, increase with increasing pH whereas A
min decreases. 相似文献
135.
Bhosale SV Kalyankar MB Nalage SV Lalander CH Bhosale SV Langford SJ Oliver RF 《International journal of molecular sciences》2011,12(3):1464-1473
Self-assembled nanostructures of zwitterionic octaphosphanatoporphyrin 1, of either nanoparticles or nanorods, depending on small changes in the pH, is demonstrated based on the J-aggregates. Porphyrin 1 self-assembled into nanosphere aggregates with a diameter of about 70-80 nm in the pH range 5-7, and nanorod aggregates were observed at pH 8.5. Hydrogen bonding, π-π stacking and hydrophilic interactions play important roles in the formation of this nanostructure morphology. Nanostructures were characterized by UV/Vis absorbance, fluorescence, atomic force microscopy (AFM) and transmission electron microscopy (TEM). This interesting pH dependent self-assembly phenomenon could provide a basis for development of novel biomaterials. 相似文献
136.
137.
The formation of Fe3O4 nanoparticles by hydrothermal process has been studied. X‐ray Diffraction measurements were carried out to distinguish between the phases formed during the synthesis. Using the synthesized Fe3O4 nanoparticles, poly(vinyledene fluoride)‐Fe3O4 composite films were prepared by spin coating method. Scanning electron microscopy of the composite films showed the presence of Fe3O4 nanoparticles in the form of aggregates on the surface and inside of the porous polymer matrix. Differential Scanning calorimetry revealed that the crystallinity of PVDF decreased with the addition of Fe3O4. The conductitivity of the composite films was strongly influenced by the Fe3O4 content; conductivity increased with increase in Fe3O4 content. Vibration sample magnetometry results revealed the ferromagnetic behavior of the synthesized iron oxide nanoparticles with a Ms value of 74.50 emu/g. Also the presence of Fe3O4 nanoparticles rendered the composite films magnetic. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
138.
Nonwoven nanofiber mats of polyvinylidene fluoride (PVDF) with modified layered double hydroxide (MLDH) were prepared by electrospinning. The fiber morphology was studied using scanning electron microscopy. X‐ray diffraction and FTIR spectroscopy was used to characterize the polymorphism in electrospun mats. Fibers of diameter in the range 80–800 nm with beads of about 2–3 µm size were observed for pure PVDF, while in case of PVDF/MLDH nanocomposites the number and size of beads were found to be significantly reduced. Uniform and fine nanofibers were obtained at lower content of MLDH, but slightly rough surface was seen for higher content. FTIR and X‐ray diffraction patterns signify various crystalline forms of electrospun PVDF. The content of polar β‐crystalline phase of PVDF, which exhibit piezo and ferroelectric properties was found to be enhanced significantly due to reinforcement of MLDH. Use of these nanofiber mats for heavy metal Cu (II) removal was explored. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4508–4515, 2013 相似文献
139.
C. ShekharPant Mada S. S. N. M. Santosh Shaibal Banerjee Pawan K. Khanna 《Propellants, Explosives, Pyrotechnics》2013,38(6):748-753
The paper reports the energization of Hydroxyl‐Terminated Polybutadiene (HTPB) by functionalizing explosophore NO2 over the HTPB backbone, resulting in the formation of conjugated nitro‐alkene derivative of HTPB. A convenient, inexpensive and efficient “one pot” procedure of synthesizing Nitro‐Functionalized Hydroxyl‐Terminated Polybutadiene (Nitro‐HTPB) is reported. The reaction was carried out with sodium nitrite and iodine. To retain the unique physico‐chemical properties of HTPB, functionalization by NO2 group was restricted to 10 to 15 % of double bonds. The Nitro‐HTPB was characterized by FTIR, 1H NMR, VPO, DSC, TGA etc. The polymer has shown good thermal stability for practical applications. The kinetic parameters for the decomposition of Nitro‐HTPB at 150–300 °C were obtained from non‐isothermal DSC data. 相似文献
140.
Jung Ho Yoon Santosh Laxman Ingale Jin Soo Kim Kwang Hyun Kim Jayant Lohakare Yoon Kyung Park Jun Cheol Park Ill Kyong Kwon Byung Jo Chae 《Journal of the science of food and agriculture》2013,93(3):587-592
BACKGROUND: The increase in drug‐resistant bacteria and the ban on antibiotic growth promoters worldwide make the search for novel means of preventing bacterial infection and promoting growth performance imperative. In this sense, antimicrobial peptides are thought to be ideal candidates owing to their antimicrobial properties, broad spectrum of activity and low propensity for development of bacterial resistance. The aim of the present study was to investigate the effect of dietary supplementation with antimicrobial peptide‐P5 (AMP‐P5) on weanling pig nutrition. RESULTS: A total of 240 weanling pigs were allotted to four treatments on the basis of initial body weight. There were four replicates in each treatment, with 15 pigs per replicate. Dietary treatments were negative control (NC, basal diet without antimicrobial), positive control (PC, basal diet + 1.5 g kg?1 apramycin), basal diet with 40 mg kg?1 AMP‐P5 (P5‐40) and basal diet with 60 mg kg?1 AMP‐P5 (P5‐60). Pigs fed the PC or P5‐60 diet showed improved (P < 0.05) overall growth performance, apparent total tract digestibility of dry matter, crude protein and gross energy and reduced (P < 0.05) faecal and intestinal coliforms compared with pigs fed the NC diet. CONCLUSION: The results obtained in this study indicate that dietary supplementation with 60 mg kg?1 AMP‐P5 has the potential to improve the growth performance and apparent total tract digestibility of nutrients and reduce coliforms in weanling pigs. © 2012 Society of Chemical Industry 相似文献