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[en] Due to the strong constraint from the LUX experiment, the scalar portal dark matter cannot generally explain a gamma-ray excess in the galactic center by the annihilation of dark matter to bb"¯. With the motivation of eliminating the tension, we add a scalar dark matter to the aligned two-Higgs-doublet model, and focus on a simplified scenario, which has two main characteristics: (i) The heavy CP-even Higgs is the discovered 125 GeV Higgs boson, which has the same couplings to the gauge bosons and fermions as the SM Higgs. (ii) Only the light CP-even Higgs mediates the dark matter interactions with SM particles, which have no couplings to WW and ZZ, but have the independent couplings to the up-type quarks, down-type quarks and charged leptons. We find that the tension between 〈σv〉_S_S_→_b_b_"¯ and the constraint from LUX induced by the scalar portal dark matter can go away for the isospin-violating dark matter–nucleon coupling with −1.0< f"n/f"p<0.7, and the constraints from the Higgs search experiments and the relic density of Planck are also satisfied
[en] Imposing the theoretical constraints from vacuum stability, unitarity and perturbativity as well as the experimental constraints from the electroweak precision data, flavor observables and the non-observation of additional Higgs at collider, we study the implications of available Higgs signals on a two-Higgs-doublet model with the alignment of the down-type quarks and charged lepton Yukawa coupling matrices. Compared to the four traditional types of two-Higgs-doublet models, the model has two additional mixing angles θ_d and θ_l in the down-type quark and charged lepton Yukawa interactions. We find that the mixing angle θ_d can loose the constraints on sin (β−α), tan β and m_H_"± sizably. The model can provide the marginally better fit to available Higgs signals data than SM, which requires the Higgs couplings with gauge bosons, uu-macron and dd-macron to be properly suppressed, and favors (1 <θ_d< 2, 0.5 <θ_l< 2.2) for m_h= 125.5 GeV and (0.5 <θ_d< 2, 0.5 <θ_l< 2.2) for m_H= 125.5 GeV. However, these Higgs couplings are allowed to have sizable deviations from SM for (m_h= 125.5 GeV, 125.5 ≤m_H≤ 128 GeV) and (125 GeV ≤m_h≤ 125.5 GeV, m_H= 125.5 GeV)
[en] A light pseudoscalar of the lepton-specific 2HDM can enhance the muon g-2, but suffer from various constraints easily, such as the 125.5 GeV Higgs signals, non-observation of additional Higgs at the collider and even B_s→μ"+μ"−. In this paper, we take the light CP-even Higgs as the 125.5 GeV Higgs, and examine the implications of those observables on a pseudoscalar with the mass below the half of 125.5 GeV. Also the other relevant theoretical and experimental constraints are considered. We find that the pseudoscalar can be allowed to be as low as 10 GeV, but the corresponding tan β, sin (β−α) and the mass of charged Higgs are strongly constrained. In addition, the surviving samples favor the wrong-sign Yukawa coupling region, namely that the 125.5 GeV Higgs couplings to leptons have opposite sign to the couplings to gauge bosons and quarks.
[en] We study the implications of the LHC diphoton and Z+photon Higgs signals on the Higgs triplet model with Y=0, which predicts two neutral CP-even Higgs bosons h, H and a pair of charged Higgs H"±. We discuss three different scenarios: (i) the observed boson is the light Higgs boson h; (ii) it is the heavy Higgs boson H; (iii) the observed signal is from the almost degenerate h and H. We find that the inclusive Higgs diphoton rates in the first two scenarios can be enhanced or suppressed compared to the SM value, which can respectively fit the ATLAS and CMS diphoton data within 1σ range. The inclusive ZZ"∗ rates are suppressed, which are outside 1σ range of ATLAS data and within 1σ range of CMS data. Meanwhile, another CP-even Higgs boson production rate can be suppressed enough not to be observed at the collider. For the third scenario, the Higgs diphoton rate is suppressed, which is outside 1σ range of ATLAS data, and the ZZ"∗ rate equals to SM value approximately. In addition, we find that the two rates of h→γγ and h→Zγ have the positive correlations for the three scenarios
[en] The non-condensable radiolytic gas could accumulate in a pipeline with dead end on the top induced by condensation due to imperfect insulation. This has already led to unforeseen combustion during the operation of BWR systems, and cost considerable damages. The chef strategy in Europe was to avoid radiolytic gas accumulations in branch lines from the very beginning. One possible solution is to modify the pipeline avoiding non-vented dead end at the top of pipeline systems and allowing the radiolytic gas to diffuse back to the main flow. The main objection of this study is to conduct a preliminary assessment for a new modified measurement pipeline for BWR with GASFLOW-MPI, evaluating the long-term radiolytic gas accumulation. The radiolytic gases can interact with the condensing film through absorption and degassing. The model for the non-condensable gas absorption in the condensing film is developed in GASFLOW-MPI to simulate this process. Then the experiment of the non-condensable enrichment in the pipeline of the Residual Heat Removal System (RHRS) for the Hamaoka Nuclear Power Plant and is modeled and simulated to validate the model. The calculated temperature profiles along the pipe centerline agree well with the experimental data indicating that GASFLOW-MPI can provide reasonable predictions for radiolytic gas accumulation in a complex pipeline. Then a 2D model for a modified measurement pipeline of BWR is built and analyzed with GASFLOW-MPI to evaluate the long-term radiolytic gas accumulation. Different from the cases in literatures, the modified pipeline has the reservoir (main flow) locating at the top and the dead end of locating at the bottom, meanwhile the horizontal parts is modified slightly ascending to allow the radiolytic gas to diffuse upwards. The result shows that the non-condensable gas will not be significantly enriched locally at the dead end of the pipe, because the gravity and the momentum work against with each other in this case. On one hand, the pipeline take suction from the main flow, which pushes condensed gas in the pipe to the bottom, meanwhile, the condensed gas mixture tends to move towards the reservoir because the gas enriched with non-condensable gases has lower density. In the end, a steady status can be reached under these two mechanisms, with the maximum concentration of non-condensable gases below the combustion limitation. Therefore, the long-term radiolytic gas accumulation can be mitigated through the modified design of the pipeline. (author)
[en] Highlights: • Copper addtion increases the recrystallization volume fraction of 7XXX alloys. • The number of precipitated phases rises with the addition of copper. • Strength and elongation can be enhanced by copper. • Copper additon plays a key role in turning quasi-cleavage fracture to dimple fracture. - Abstract: The effect of copper content on tensile properties and microstructure of 7XXX series aluminum alloys at 90% deformation is investigated by tensile test, optical microscopy, scanning electronic microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that higher Cu-containing alloy would precipitate more quantity of second-phase particles in rolling process at 420 °C, which facilitates the process of recrystallization during solution treatment. With the increase of copper content from 0 to 1.6 wt.%, the density of ç′ phase and the degree of recrystallization increase, meanwhile the strength and plasticity of Al–Zn–Mg–Cu alloy are improved in T6 heat treatment. In addition, the tensile fracture of Cu-free alloy belongs to quasi-cleavage fracture, while the tensile fracture of Cu-containing alloy is dimple fracture and the number of dimples increases with the increasing of copper content
[en] Sphere-shaped bismuth vanadate (BiVO_4) was synthesized by a simple and cost-effective low temperature hydrothermal method. In order to improve the photo-response of the prepared sphere-shaped BiVO_4 in natural sunlight, the as-synthesized BiVO_4 incorporated with graphene oxide (GO) was assembled into sphere-shaped BiVO_4/reduced graphene oxide (RGO) composites. For studying their morphological, physical, optical, and photo-chemical properties, the obtained composites were well characterized with the aid of various physicochemical techniques, such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance, N_2 adsorption/desorption and electrochemical measurements. In addition, the photocatalytic performance of the prepared BiVO_4 and BiVO_4/RGO composites were evaluated by monitoring the degradation of Rhodamine B (RhB)-contained wastewater under natural sunlight irradiation, where the highest photocatalytic degradation efficiency can be achieved for the BiVO_4/RGO composites with 3 wt% RGO dosage (approx. 68.85% increase compared with that of pure sphere-shaped BiVO_4) The improved photocatalytic activity of BiVO_4/RGO composite is attributed to the formation of well-defined BiVO_4-RGO interfaces, which greatly enhances the charge separation efficiency. - Highlights: • One-pot synthesis of sphere-shaped BiVO_4/RGO composite was presented. • The composite showed improved direct sunlight-driven photocatalytic activity. • The origin of the enhanced photocatalytic performances was discussed. • h"+ directly oxidation of substrates suppressed the formation rate of "·OH.
[en] The T-parity in the littlest Higgs model can be broken by the anomalous Wess—Zumino—Witten term, which leads that the lightest T-odd gauge boson AH decays into the SM particles. First, we examine some lepton flavor violating decays of AH, namely AH → τ± μ∓, AH → τ±e∓, and AH → μ±e∓. We find that the branching ratios can reach 10−7 for AH → τ±μ∓, 10−8 for AH → τ±e∓, and 10−8 for AH → μ±e∓. Then, we study the lepton flavor violating plus jets signatures of the heavy charged gauge boson and mirror quarks at the LHC, and find that it is possible to be detected for pp → qHq-bar H → τ±μ∓ + 4 jets, and hardly to be detected for pp → qHq-bar H → τ±e∓(μ±e∓) + 4 jets and pp →WHWH → τ±μ∓ (τ±e∓,μ±e∓) + 6 jets. (physics of elementary particles and fields)
[en] Objective: To assess the short-term efficacy of bronchial artery infusion (BAI) of Gemcitabine (GEM) plus Cisplatin (DDP) combined with systemic chemotherapy of GEM for advanced non-small cell lung cancer (NSCLC). Methods: A total of 60 patients with pathologically proved primary NSCLC were randomly selected. BAI with GEM (1000 mg/m2) and DDP (DDP 50 mg/m2) was performed on the first day, and systemic chemotherapy of GEM (1000 mg/m2) was carried out on the eighth day. The clinical results were analyzed. Results: Of the 60 patients, CR, PR, SD and PD were obtained in 3, 35, 17 and 5, respectively, with an overall effective rate of 63%. Twenty-two patients had adenocarcinoma and the effective rate of them was 45%. Thirty-eight patients had squamous cell carcinoma and their effective rate was 74%. The difference in the effective rate between the above two pathologic types was significant (P<0.05). Central type lung cancer was seen in 37 cases, their effective rate was 73%. The peripheral type lung cancer was seen in the remaining 23 patients and the effective rate was 48%. The difference in the effective rate was statistically significant between the central type and the peripheral type (P<0.05). Conclusion: The combination of bronchial artery infusion with systemic chemotherapy by using GP plan is an effective, feasible approach in the treatment of advanced non-small cell lung cancer. The short-term efficacy of the treatment bears a close relationship to the anatomical location and pathological type of the cancer. (authors)
[en] Base on two-dimension small-world networks, a susceptible-infected model with epidemic alert is proposed in this Letter. In this model, if some parts of the network are alarmed as dangerous, a fraction of edges between the alarmed parts and others will be removed, and two cases of alerting rules that the degree and frequency of contacts kept unchanged are considered respectively. The numerical simulations show that the spreading velocity is reduced by the accurate and timely epidemic alert, and the more accurate and timely, the stronger the deceleration effect. This model indicates that to broadcast epidemic alert timely is helpful and necessary in the control of epidemic spreading, and in agreement with the general view of epidemic alert. This work is helpful to understand the effects of epidemic alert on disease spreading