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951.
CdHgTe/SiO2 nanoparticles were prepared by SiO2 capping on the surface of CdHgTe QDs. The characteristics, such as optical spectra, photostability, size and cell toxicity
were investigated. The dynamic distribution of CdHgTe/SiO2 nanoparticles was in vivo monitored by near infrared fluorescence imaging system. CdHgTe/SiO2 nanoparticles acted as a novel fluorescence probe have a maximum fluorescence emission of 785 nm and high photo-stability.
The hydrodynamic diameter of CdHgTe/SiO2 nanoparticles could be adjusted to 122.3 nm. Compared to CdHgTe QDs, inhibitory effects of CdHgTe/SiO2 nanoparticles on proliferation of HCT116 cells decreased to a certain extent. CdHgTe/SiO2 nanoparticles had their specific dynamic distribution behavior, which provided new perspectives for bio-distribution of nanoparticles. 相似文献
952.
P. C. Peng H. Y. Wang R. L. Lan H. H. Lu G. R. Lin G. Lin J. Y. Chi 《Laser Physics》2012,22(9):1373-1377
This study investigates, for the first time, static and dynamic wavelength switching characteristics of the 1.3 ??m quantum-dot vertical-cavity surface-emitting laser (QD VCSEL). The free-running QD VCSEL with ??1 and ??2 state innately is injected by a laser source with ??1 state. When the injection power exceeds the threshold power, the dominant state of the QD VCSEL changes from ??2 to ??1 state. Results of this study demonstrate that the wavelength switching based on a 1.3 ??m QD VCSEL has a simpler and more cost-effective configuration than those of previous systems. 相似文献
953.
Nida Iqbal Rabia NazirAnila Asif Aqif Anwar ChaudhryMuhammad Akram Goh Yi FanAftab Akram Rashid AminSung Ha Park Rafaqat Hussain 《Current Applied Physics》2012,12(3):755-759
Polyvinyl alcohol (PVA) coated hydroxyapatite was deposited onto a 316L stainless steel substrate by electrophoretic deposition. Deposition was carried out in a methanol suspension at pH 5.5 using a graphite rod as an anode. Parameters such as PVA concentration, deposition voltage and time were optimized to achieve a homogeneous, crack-free adhesive coating. Techniques such as X-ray diffraction and Fourier transform infrared spectroscopy were used to study the phase composition of the coated materials and the stability of hydroxyapatite in the presence of PVA. 相似文献
954.
In this paper, we propose and experimentally demonstrate a novel optical packet switching scheme with one core router and two edge routers, in which an orthogonal frequency division multiplexing (OFDM) signal is generated as a label. In this experiment there are two transmission spans, each span consists of 50-km SMF-28 and an erbium-doped optical fiber amplifier (EDFA) without dispersion management. A 10 Gb/s on-off keying (OOK) optical payload and a 2.5 Gb/s OFDM optical label are generated, encapsulated, and transmitted in the first span. And then old label is replaced by new label, the generated new optical packet after transmission over the second span is detached and detected. The transmission performance of the optical label and payload is experimentally investigated at the ingress router, core router and egress router. 相似文献
955.
Adachi I Aihara H Asner DM Aulchenko V Aushev T Aziz T Bakich AM Bay A Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Browder TE Chen P Cheon BG Chilikin K Chistov R Cho K Choi SK Choi Y Dalseno J Danilov M Doležal Z Drásal Z Eidelman S Epifanov D Fast JE Gaur V Gabyshev N Garmash A Goh YM Golob B Haba J Hara K Hara T Hayasaka K Hayashii H Higuchi T Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T Julius T Kapusta P Katayama N 《Physical review letters》2012,108(17):171802
We present a precise measurement of the CP violation parameter sin2φ1 and the direct CP violation parameter A(f) using the final data sample of 772×10(6) BB[over ˉ] pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. One neutral B meson is reconstructed in a J/ψK(S)(0), ψ(2S)K(S)(0), χ(c1)K(S)(0), or J/ψK(L)(0) CP eigenstate and its flavor is identified from the decay products of the accompanying B meson. From the distribution of proper-time intervals between the two B decays, we obtain the following CP violation parameters: sin2φ1=0.667±0.023(stat)±0.012(syst) and A(f)=0.006±0.016(stat)±0.012(syst). 相似文献
956.
Li J Adachi I Aihara H Arinstein K Asner DM Aulchenko V Aushev T Bakich AM Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Brovchenko O Browder TE Chang MC Chen A Chen P Cheon BG Chistov R Cho K Choi SK Choi Y Dalseno J Doležal Z Drutskoy A Eidelman S Esen S Fast JE Gaur V Garmash A Goh YM Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T Julius T Kang JH Kapusta P Katayama N Kawasaki T 《Physical review letters》2012,108(18):181808
We report first observations of B(s)(0) → J/ψη and B(s)(0) → J/ψη'. The results are obtained from 121.4 fb(-1) of data collected at the Υ(5S) resonance with the Belle detector at the KEKB e+ e- collider. We obtain the branching fractions B(B(s)(0) → J/ψη)=[5.10±0.50(stat)±0.25(syst)(-0.79)(+1.14)(N(B(s)(*) B(s)(*))]×10(-4), and B(B(s)(0) → J/ψη')=[3.71±0.61(stat)±0.18(syst)(-0.57)(+0.83)(N(B(s)(*) B(s)(*))]×10(-4). The ratio of the two branching fractions is measured to be (B(B(s) → J/ψη'))/(B(B(s) → J/ψη))=0.73±0.14(stat)±0.02(syst). 相似文献
957.
Chung KH So CM Wong SM Luk CH Zhou Z Lau CP Kwong FY 《Chemical communications (Cambridge, England)》2012,48(14):1967-1969
A new class of easily accessible hemilabile benzimidazolyl phosphine ligands has been developed. The ligand skeleton is prepared from commercially available and inexpensive o-phenylenediamine and 2-bromobenzoic acid. With catalyst loading down to 0.5 mol% palladium, excellent catalytic activity towards the Suzuki-Miyaura coupling of aryl mesylates is still observed. This represents the lowest catalyst loading achieved so far for this reaction in general. X-Ray crystallography shows that new ligand L2 is coordinated with Pd in a κ(2)-P,N fashion. 相似文献
958.
Shen ZL Goh KK Wong CH Loo WY Yang YS Lu J Loh TP 《Chemical communications (Cambridge, England)》2012,48(47):5856-5858
The synthesis of recyclable ionic liquid-supported imidazolidinone catalyst I and its application in 1,3-dipolar cycloaddition of nitrone with α,β-unsaturated aldehyde with high performance were described. Most importantly, the catalyst I can be recovered and recycled for up to five runs without observing significant decrease in catalytic activity. 相似文献
959.
Sheng-Hung Wu Hung-Cheng Chou Ryh-Nan Pan Yi-Hao Huang Jao-Jia Horng Jen-Hao Chi Chi-Min Shu 《Journal of Thermal Analysis and Calorimetry》2012,109(1):355-364
Organic peroxides (OPs) and inorganic peroxides (IPs) are usually employed as an initiator for polymerization, a source of free radicals, a hardener, and a linking agent in low density polyethylene (LDPE), polyvinyl chloride (PVC), controlled-rheology polypropylene (CR-PP), and styrene industries. Worldwide, due to their unstably reactive natures, OPs and IPs have caused many serious thermal explosions and runaway reaction incidents. This study was conducted to elucidate its essentially hazardous characteristics. To analyze the runaway behavior of OPs and IPs in the traditional process, thermokinetic parameters including heat of decomposition (??H d ), exothermic onset temperature (T 0), self-accelerating decomposition temperature (SADT), time to maximum rate (TMR), critical temperature (T c ), etc., were measured by calorimetric approaches involving differential scanning calorimetry (DSC), vent sizing package 2 (VSP2), and calculation method. Safety and health handling information of hazardous materials and toxic substances is noted in material safety data sheets (MSDS) and was applied to analyze in process safety management (PSM) in the chemical industries, but MSDS are not providing important handling indicators concerning the SADT, TMR, T c , etc. In view of loss prevention, more useful indicators must be provided in the sheets or guide book. 相似文献
960.
Dibyendu Bhattacharya Che‐Hao Chang Yu‐Hsiang Cheng Long‐Li Lai Hsiu‐Yu Lu Ching‐Yao Lin Kuang‐Lieh Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(17):5275-5283
Self‐assembled, hexarhenium(I), triangular metalloprism compound [{(CO)3Re(μ‐ 2 )Re(CO)3}3(μ3‐ 1 )2] ( 3 ) featuring three bis‐chelating pillarlike indigo dianions (μ‐ 2 ), each of which connects two fac‐Re(CO)3 cores, which are interconnected by a tritopic N donor, that is, a 2,4,6‐tris(4‐pyridyl)‐1,3,5‐triazine (μ3‐ 1 , tPyTz) ligand, has been synthesized in high yield and characterized. Metalloprism 3 exhibits a strong absorption in the near‐infrared (NIR) region. The reversible, multielectron redox properties of the electrogenerated 3 n species, where n=3+, 0, 3?, 4?, 5?, 8?, in the visible and especially in the NIR region were investigated in THF solution by cyclic voltammetry (CV), chronocoulometry, EPR spectroscopy, and thin‐layer UV/Vis/NIR spectroelectrochemistry (SEC). Stepwise, site‐specific electrochemical reductions lead to the formation of a series of highly stable ion (radical) species in which electrons associated with μ‐ 2 or μ3‐ 1 components of the molecule can be clearly distinguished. An EPR investigation revealed interaction of unpaired electrons with the metal nuclei (185,187Re, I=5/2) in the reduced intermediates. The framework has C2 symmetry, and accidental degeneracies suffice. Detailed theoretical calculations by structure‐based DFT confirm that the triply degenerate HOMO has ≥70 % indigo character with a sizable dπ‐Re character, while the LUMO is dominated by the triply degenerate indigo ligands, and the LUMO+1 by doubly degenerate tPyTz ligands. A comparison of 3 and previously reported 2,2′‐bis‐benzimidazolate‐ (BiBzlm) or alkoxy‐pillared ReI metalloprisms indicates a very low switching potential with a potential window of less than 1 V and reversibly accessible optical properties with higher stability of the intermediates. The properties exhibited by 3 appear to be due to the slight tuning of the bridging ligand from N,N? to N,O?. 相似文献