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51.
Highly-conductive poly(3,4-ethylene dioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) films obtained by the addition of dimethylsulfoxide (DMSO) and the argon plasma exposure were used as a transparent conductive anode (TCA) for copper-phthalocyanine (CuPc)/C60 organic thin-film solar cells (OSCs). The CuPc/C60 OSCs on as-grown DMSO added PEDOT:PSS layer showed a power efficiency of 0.6%, whereas it was improved markedly to 1.34% after the atmospheric-pressure argon plasma exposure, which was comparable to that formed on indium-tin-oxide layer. Effects of the DMSO addition and the argon plasma exposure in the spin-coated PEDOT:PSS films is demonstrated in terms of the in-depth characterization of optical and electrical properties.  相似文献   
52.
This study examined the behavioral mechanisms that support transfer of food from adults to infants in tufted capuchins (Cebus apella). Two captive groups of capuchins were presented with abundant quantities of unshelled pecans or commercial pellets. Five of 11 infant subjects could not open the nuts. A variety of tolerated interactions were initiated by infants toward adults, and food was frequently transferred. All such interactions were more frequent with nuts (a preferred food) than with pellets. Adult capuchins were equally tolerant of infant capuchins that could open nuts and those that could not. Tolerated interactions during feeding could result in acquisition of dietary information by young capuchins or to important, if intermittent, nutritional support.  相似文献   
53.
A protocol-free parallel optical interconnecting module is introduced as a solution to solve memory test system transmission bottlenecks. The optical transmission system flexibly suited for a memory test system is reviewed and discussed. A parallel optical module capable of transmitting from dc to 34.1Gb/s (4.267 Gb/s /spl times/8 ch) has been developed. A data transmission throughput density per unit volume of 19 Gb/s/cm/sup 3/ is achieved. A random jitter of less than 3-ps root-mean-square is also achieved. Furthermore, high-density optical connector, high-density optical fiber cable, fiber guides, and cable management/reinforcement members suited for mechanical requirements of the memory test system have been developed.  相似文献   
54.
Yerba mate extract (Ilex paraguariensis) is a source of phenolic compounds that possesses in vitro antioxidant activities and may contribute to a reduction in the risk of cardiovascular disease. In this study we examined the acute effects of the consumption of mate infusion on ex vivo plasma and low-density lipoprotein (LDL) oxidation, plasma antioxidant capacity, and platelet aggregation. Twelve healthy fasted subjects ingested 500 mL of mate infusion and blood samples were collected before and 1 h after mate intake. Lipid peroxidation of plasma and LDL was monitored by the measurement of cholesteryl-ester hydroperoxides (CE-OOH) and cholesterol oxides. The plasma antioxidant capacity was measured as ferric-reducing antioxidant potential (FRAP). Platelet aggregation was evaluated in platelet-rich plasma stimulated with adenosine diphosphate and coagulation was tested in platelet-poor plasma. Ingestion of mate infusion diminished the ex vivo oxidizability of both plasma and LDL particles. After mate intake, the CE-OOH levels were around 50% lower in plasma oxidized with copper or 2,2′-azobis[2-amidine-propane-hydrochloride] (AAPH) and the lag time to plasma oxidation increased 2-fold (P < 0.05). Copper- and AAPH-induced LDL peroxidation were also inhibited by around 50% and 20%, respectively, after mate consumption (P < 0.05). The levels of various oxysterols were significantly reduced in oxidized-plasma and LDL (P < 0.05) and FRAP increased by 7.7% after mate intake (P < 0.01). However, mate consumption did not inhibit platelet aggregation or blood coagulation. In summary, intake of yerba mate infusion improved the antioxidant capacity and the resistance of plasma and LDL particles to ex vivo lipid peroxidation.  相似文献   
55.
Delay to large scale projects, which is as a result of actions or inactions of some project stakeholders, is becoming a global phenomena and Ghana is no exception. The objective of the research is to identify, rate and rank the most significant risk factors that causes delay on projects and examine the social impact of these delays to recommend modalities to help mitigate these risk factors. The study adopted quantitative methods with the distribution of 144 questionnaires to built environment professionals receiving a response rate of 75.7%. The instrument listed 58 common factors under eight categories that contribute to the causes of delay for respondents to rate. Analysis of data non-parametric test revealed that client, contractor, material and finance category factors significantly resulted in the schedule delay of large infrastructural projects. The survey analysis revealed that micro-factors that result in delays to large construction projects are time constraint, cost overrun, payment problems, dispute and litigation. The research recommended the following modalities to minimize such delays: availability of resources, improved communication and coordination, proper scope definition and feasibilities, utilization of modern technology, appropriate application of technologically based systems and competent project management's structures.  相似文献   
56.
We have successfully synthesized zinc oxide microrods perpendicularly oriented on hexagonal ZnO sheets by a simple heat treatment approach using LDH (layered double hydroxide) precursor in an aqueous solution. The synthesized ZnO microrods have an average diameter of 500 nm and length of 2–3 μm, and form highly-oriented array. In this work, the effect of heating temperature and time on morphology and orientation of ZnO microrods was studied experimentally and the formation mechanism was discussed in detail. Transformation from hexagonal precursor to ZnO microrods can be attributed to dissolution and re-precipitation of the precursor, which should be caused by its thermal unstability under heating temperature.  相似文献   
57.
Using the electrochemical deposition method, CdS thin films were deposited from acid solutions (pH = 2.5) containing CdS04 and Na2S203 on indium-oxide coated glass substrates. These films were annealed in N2, air, or O2 atmosphere at 200–500°C for 30 min. Photoluminescence spectra were measured at 77 K. For the films annealed in N2, the band edge emission became weaker and the luminescence due to defects shifted to longer wavelengths as the annealing temperature was raised above 300°C. However, for the films annealed in air or O2, the band edge emission was observed strongly irrespective of the annealing temperature and the luminescence due to defects was weak. Thus the O2 annealing is useful for the defects reduction.  相似文献   
58.
Cell cycle analysis using flow cytometer (FCMX) was performed to evaluate the influence of cyclosporin A (CsA) on cellular proliferation during compensatory renal growth (CRG) in uninephrectomized (Ux) rats. CsA (50 mg/kg/day) was administered subcutaneously for 7 days and animals were scarificed 0, 12, 24, 48, 72, 120 and 168 h after Ux. The percent changes in the S (DNA synthesis) and G2M (DNA replication) phases in the contralateral kidney were analyzed. The cortical cells entering the S and G2M phases showed significant differences between CsA and vehicle groups (p = 0.0001, p = 0.001, respectively), but the medullary cells entering the S and G2M phases showed no significant differences between the 2 groups (p = 1.000, respectively). In the cortex, the CsA group showed a significant decrease in the S (at 12, 72 and 120 h) and G2M phases (at 24, 72 and 120 h) compared to the vehicle group (p < 0.05, respectively), but there was no significant difference in the medulla. In conclusion, cellular proliferation is suppressed in cortical cells by CsA.  相似文献   
59.
Precise metabolic flux analysis (MFA) by gas chromatography-mass spectrometry (GC-MS) and computer calculation was performed, and the consistency of the estimated results was verified by independently performed nuclear magnetic resonance (NMR) analysis. The precise estimation of flux by the integration method of the mass isotopomer signal, defined as the coefficient of variance (CV) of multiple determination, was investigated, and the results estimated using different data sets with the same magnitude of error were confirmed. The CV of multiple determinations was sufficiently small to discuss and compare the fluxes of a metabolic pathway. The estimated fluxes using the GC-MS data were cross-validated with the NMR data that were independently measured and not used for MFA. The developed method was successfully applied to the MFA of the growth phase of two different glutamate-producing coryneform bacteria, Corynebacterium glutamicum and C. efficiens. The difference in the growth rate between these two bacterial species was discussed while considering the results of MFA, including forward and backward (exchange) fluxes.  相似文献   
60.
A modified current pulsed Q (EMQ)-switched CO2 laser which is Q-switched by a mechanical beam chopper in combination with a pulsed discharge current is discussed. The laser produces a very stable output with a peak power greater than 1 kW at a repetition rate of 1000 p.p.s. for all transitions in the P and R branches of the CO2 spectrum. A CH3F laser pumped by the EMQ-switched laser produces 496 μm radiation in a 6.5 W peak, 100 ns pulses at 500 p.p.s. in the lowest loss EH11 mode  相似文献   
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