[en] The formation of polycation chitosan, CS, with polyanion lignosulfonate, LGS, multilayer films based on layer-by-layer self-assembly method was investigated by several techniques. UV absorption spectra showed that the growth of both CS and LGS layers followed the exponential model. The film surface wettability was found alternated depending on the surface properties of these two materials because the contact angle is smaller for the CS layer and greater for the LGS layer while the surface free energy is known greater for the former and smaller for the latter. AFM images indicated that the surface roughness of these layers was in nanosize and was increased with the layer number due to the aggregation. The field emission scanning electron microscope photograph showed that the average thickness of each layer was about 5–6 nm. - Highlights: ► The chitosan/lignosulfonate (CS/LGS) multilayer films were self-assembled following the exponential model. ► The film surface wettability was alternated depending on the surface properties of CS and LGS. ► The surface roughness of these layers was in nanosize and increased with the layer number due to the aggregation.

[en] Dipole operator s^¯σ_μνF^μνb requires the helicity flip in the involving quark states thus the breaking of chiral U(3)_Q×U(3)_d. On the other hand, the b quark mass generation is also a consequence of chiral U(3)_Q×U(3)_d symmetry breaking. Therefore, in many models, there might be strong correlation between the b→sγ and b quark Yukawa coupling. In this Letter, we use non-decoupling MSSM model to illustrate this feature. In the scenario, the light Higgs boson may evade the direct search experiments at LEPII or Tevatron while the 125 GeV Higgs-like boson is identified as the heavy Higgs boson in the spectrum. A light charged Higgs is close to the heavy Higgs boson which is of 125 GeV and its contribution to b→sγ requires large supersymmetric correction with large PQ and R-symmetry breaking. The large supersymmetric contribution at the same time significantly modifies the b quark Yukawa coupling. With combined flavor constraints B→X_sγ and B_s→μ⁺μ⁻ and direct constraints on Higgs properties, we find best fit scenarios with light stop of O(500 GeV), negative A_t around −750 GeV and large μ-term of 2–3 TeV. In addition, reduction in bb^¯ partial width may also result in large enhancement of ττ decay branching fraction. Large parameter region in the survival space under all bounds may be further constrained by H→ττ if no excess of ττ is confirmed at LHC. We only identify a small parameter region with significant H→hh decay that is consistent with all bounds and reduced ττ decay branching fraction. In the end, if current dark matter mostly consists of neutralino, direct detection experiments like XENON100 also puts stringent bound over this scenario with light Higgs bosons. The light stops which are required by flavor constraints can further enhance the scattering cross section

[en] Highlights: • Porous carbon nanofibers (PCNFs) with multiform mesoporous structure could be superior to carbon black as the support to grow platinum. • PCNF may construct reasonable catalyst layer (CL) which benefit for mass transfer and water management. • The combination of excellent support and special morphological fabrication of platinum guarantee the high activity and durability of platinum catalyst. • PCNF or Pt nanowires could be as a reliable replacement to conventional support or Pt nanoparticles. - Abstract: Reducing platinum usage and increasing its electrocatalytic durability are the key issues for the successful application of PEMFC. Fabricating platinum into specific morphologic structure and combining with the superior support is one of effective resolutions. In this paper, porous carbon nanofibers supported platinum nanowires (PtNW/PCNF) were synthesized via a simple and inexpensive template-free methodology and used oxygen reduction reaction (ORR) electrocatalyst. As a comparison, Pt nanowires supported on commercial carbon black (PtNW/Vulcan) was also prepared in the same condition. High-resolution transmission electron microscopy (TEM) shows that the single-crystal Pt nanowires were successfully grown on the support. The electrocatalytic activity and stability of the resultant catalysts along with the commercial one (JM20) were investigated by using cyclic voltammetry (CV) and liner sweep voltammetry (LSV) with a rotating disk electrode (RDE). As a result, the PtNW/PCNF exhibited much enhanced electrocatalytic activity and stability compared with the PtNW/Vulcan and JM20. The mass activity (at 0.80 V vs. RHE) of the PtNW/PCNF is about 1.7 and 2.3 times higher than that of PtNW/Vulcan and JM20, respectively. The remnant ECSA of the PtNW/PCNF after 1000 cycles was about 32% compared with the initial one whereas JM20 and PtNW/Vulcan retained only 10% and 23%. Furthermore, after ADT test for the three electrocatalysts, PtNW/PCNF lost 51 mV in half-wave potential, significantly better than the 150 mV half-wave potential loss for PtNW/Vulcan and almost complete loss of performance for commercial JM20. These results indicate controlled growth of Pt nanowires as a potential choice for conventional Pt nanoparticles and PCNFs a promising candidate as catalyst supports for the enhancement of PEMFC performance.

[en] Tree and loop level scattering amplitudes which involve physical massless bosons are derived directly from physical constraints such as locality, symmetry and unitarity, bypassing path integral constructions. Amplitudes can be projected onto a minimal basis of kinematic factors through linear algebra, by employing four dimensional spinor helicity methods or at its most general using projection techniques. The linear algebra analysis is closely related to amplitude relations, especially the Bern-Carrasco-Johansson relations for gluon amplitudes and the Kawai-Lewellen-Tye relations between gluons and graviton amplitudes. Projection techniques are known to reduce the computation of loop amplitudes with spinning particles to scalar integrals. Unitarity, locality and integration-by-parts identities can then be used to fix complete tree and loop amplitudes efficiently. The loop amplitudes follow algorithmically from the trees. A number of proof-of-concept examples are presented. These include the planar four point two-loop amplitude in pure Yang-Mills theory as well as a range of one loop amplitudes with internal and external scalars, gluons and gravitons. Several interesting features of the results are highlighted, such as the vanishing of certain basis coefficients for gluon and graviton amplitudes. Effective field theories are naturally and efficiently included into the framework. Dimensional regularisation is employed throughout; different regularisation schemes are worked out explicitly. The presented methods appear most powerful in non-supersymmetric theories in cases with relatively few legs, but with potentially many loops. For instance, in the introduced approach iterated unitarity cuts of four point amplitudes for non-supersymmetric gauge and gravity theories can be computed by matrix multiplication, generalising the so-called rung-rule of maximally supersymmetric theories. The philosophy of the approach to kinematics also leads to a technique to control colour quantum numbers of scattering amplitudes with matter, especially efficient in the adjoint and fundamental representations.

[en] In this paper, density functional theory was used to study the adsorption characteristics of trichlorophenol on anatase TiO₂ (101) surface. Four stable adsorption configurations were optimized, and the optimal adsorption sites, adsorption energy and charge density were calculated. It is found that:four stable adsorption styles have chemical adsorption characteristics. When the H atom in hydroxyl group of trichlorophenol is adsorbed on the tricoordinated O atom of TiO₂ (101) surface, the adsorption energy is largest and this adsorption style is stablest. C-C bond length and C-Cl bond length adjacent to the adsorption site both have increase, which makes these bonds active and easy to be broken. This study will provide a theoretical basis for the subsequent studies on the degradation of trichlorophenol. (authors)

[en] This paper starts with a self-contained discussion of the so-called Akulov-Volkov action S_AV, which is traditionally taken to be the leading-order action of the Goldstino field. Explicit expressions for S_AV and its chiral version S_AV^ch are presented. We then turn to the issue on how these actions are related to the leading-order action S_NL proposed in the newly proposed constrained superfield formalism. We show that S_NL may yield S_AV/S_AV^ch or a totally different action S_KS, depending on how the auxiliary field in the former is integrated out. However, S_KS and S_AV/S_AV^ch always yield the same S-matrix elements, as one would have expected from general considerations in quantum field theory. (orig.)

[en] In this paper, the adsorption and degradation mechanism of metronidazole on TiO₂ (101) and (001) surfaces was elucidated at DFT level. The adsorption stability of metronidazole on the surface of anatase was studied under the condition of vacuum and neutral aqueous solvent respectively, and the most stable adsorption configuration was optimized theoretically. It was found that metronidazole could be adsorbed on the surface of TiO₂ under both conditions. The hydrogen bond generated by the adsorption process can enhance the stability of the adsorption structure. The surface adsorption made the CN bond length of metronidazole longer, which could facilitate the reaction of open-loop degradation. The mechanism of ring-opening degradation of metronidazole on two surfaces of TiO₂ was also studied. It was found that the activation energy of the degradation reaction of metronidazole on the crystal plane of TiO₂ was decreased under the condition of water solvent, which indicated that the solvent condition could promote the degradation of metronidazole. The utilization efficiency of different crystal planes of TiO₂ in the visible light and predicted the photocatalysis were achieved. The study found that TiO₂ (101) crystal plane catalytic degradation of metronidazole has high visible light utilization rate, explaining the experimental results.

[en] Objective: To observe the changes of serum NO/NOS concentrations in rats after whole abdominal irradiation and their relationships with intestinal radiation injury. Methods: Thirty health rats were randomly divided into three groups: normal control group, irradiation control group, and IgY protection group. The sera of rats were collected and the NO and iNOS were assayed. Results: NO and iNOS levels increased evidently in the irradiation control group in contrast with those of the normal control group (P<0.01). NO and iNOS levels increased slightly in the IgY protection group in contrast with the irradiation control group (P<0.01) and were close to the levels of the normal control group. The changes of NO and NOS concentrations were synchronous. Conclusion: NO and iNOS are good indices for detecting intestinal radiation injury. (authors)

[en] Periodic rotation noise in the outputs of multi-oscillator ring laser gyros (MRLGs) is investigated in this paper for the first time. It is proved theoretically and experimentally that noise is induced by the crosstalk between two beat-frequency signals, which are combined from the left and right circularly polarized counter-propagating beams in MRLGs. Theoretical analysis and experimental results also indicate that the fundamental frequency of this noise is equal to the frequency difference between the two beat-frequency signals and the amplitude of the fundamental component is proportional to the crosstalk ratio between the two beat-frequency signals. Further, the amplitude of the nth-order component is proportional to the nth power of the crosstalk ratio. (paper)

[en] A survey of more than 6000 participants from four distinct non-polluted and polluted regions in China was conducted to evaluate the body burden of cadmium (Cd) on the Chinese populations using urinary Cd (UCd) as a biomarker. The findings revealed that the UCd level was 1.24 μg/g creatinine (μg/g cr) for the sample population from non-polluted Shanghai, and the UCd levels exceeded 5 μg/g cr, which is the health-based exposure limit set by the World Health Organization (WHO), in 1.1% of people. The mean UCd levels in moderately polluted (Hubei and Liaoning) and highly polluted areas (Guizhou) were 4.69 μg/g cr, 3.62 μg/g cr and 6.08 μg/g cr, respectively, and these levels were 2.9 to 4.9 times the levels observed in Shanghai. Notably, the UCd levels exceeded the recently updated human biomonitoring II values (i.e., intervention or “action level”) in 44.8%–87.9% of people from these areas compared to only 5.1%–21.4% of people in Shanghai. The corresponding prevalence of elevated UCd levels (> WHO threshold, 5 μg/g cr) was also significantly higher (30.7% to 63.8% vs. 1.1%), which indicates that elevated Cd-induced health risks to residents in these areas. Age and region were significant determinants for UCd levels in a population, whereas gender did not significantly influence UCd. - Highlights: • We performed a Cd exposure survey that involved more than 6000 Chinese subjects. • The body burden of Cd in most of subjects of non-polluted Shanghai is relatively safe. • The UCd levels were much higher in the subjects from polluted areas than from Shanghai. • The UCd levels in the population from Guizhou substantially exceeded the safety limit. • Age and region were significant determinants of UCd