Twisted K-homology,Geometric cycles and T-duality

Twisted $K$-homology corresponds to $D$-branes in string theory. In this paper we compare two different models of geometric twisted $K$-homology and get their equivalence. Moreover, we give another description of geometric twisted $K$-homology using bundle gerbes. We establish some properties of geometric twisted $K$-homology. In the last part we construct $T$-duality isomorphism for geometric twisted $K$-homology.Comment: We modify the statement about the six-term exact sequence of geometric twisted $K$-homology. Some Typos are corrected. Comments are welcome

Search for single production of the heavy vectorlike TT quark with T→thT\to th and h→γγh\to \gamma\gamma at the high-luminosity LHC

The vectorlike top partners $T$ are predicted in many extensions of the Standard Model (SM). In a simplified model including a single vectorlike $T$ quark with charge $2/3$, we investigate the process $pp \to Tj$ induced by the couplings between the top partner with the first and the third generation quarks at the LHC. We find that the mixing with the first generation can enhance the production cross section. We further study the observability of the single heavy top partner through the process $pp \to T(\to th)j\to t(\to b \ell \nu_{\ell})h( \to \gamma\gamma) j$ at the high-luminosity~(HL)-LHC~(a 14 TeV $pp$ collider with an integrated luminosity of 3 ab$^{-1}$). For three typical heavy $T$ quark masses $m_T=600,800$ and 1000 GeV, the $3\sigma$ exclusion limits, as well as the $5\sigma$ discovery reach in the parameter plane of the two variables $g^{\ast}-R_L$, are respectively obtained at the HL-LHC.Comment: 13 pages, 10 figures, Matches with the published versio

From the inside out: colloidal CdSe/CdS semiconductor nanorods : a study on the influence of their structures, surface ligands, and interactions with Redox-Active (Poly)Dopamine

The main focus of this thesis was the preparation of using nanorods (NRs) as photosensitizers, and divided into three chapters, where the structure of CdSe/CdS NRs, the phase transfer of CdSe/CdS dot-in-rod NRs and the interactions between dot-in-rod NRs and dopamine / polydopamine were discussed. Larger influence of surface defect was discovered in the inside-out NRs in the photoluminescence spectroscopy then further confirmed in the transient absorption spectroscopy. The phase transfer of the dot-in-rod NRs was successful monitored by FT-IR. And the influence of surface electron trap (ns scale) and hole trap (ps scale) was discovered in photoluminescence spectroscopy then further confirmed in time-resolved emission spectroscopy and transient absorption spectroscopy. The interaction between NRs and dopamine or polydopamine differed from surface ligands. With MUA ligand, the quenching mechanism was electron transfer which was further confirmed by transient absorption spectroscopy on the polydopamine coated MUA-NRs. With HS-PEG-OCH3 ligand, the quenching mechanism was more likely to be hole transfer

An interactive medication reminder to bond senior citizens and their family members

This project is about assisting seniors in their daily life. More and more senior citizens in the world are facing the problem of living alone. After research, I find that medication is a very important part of seniors’ life. My design is about medication reminder that can also connect the seniors with their family members. At first, I focused on the social relationship of senior citizens and started to research medication reminders in the market. I also read many books and magazines about the medication of senior citizens and try to figure out the size and volume of my design. Then I made mockups to try to test the best way for seniors to control a reminder such as the behavior of remembering medications to take. After that, I made my prototypes and brought them to the nursing home. More refinements were made after these discussion in the nursing home. The final version of my design uses an interesting and noticeable way to remind senior citizens to take their medicine. Besides that, my product can connect to phone or a device of seniors’ family members, which gives seniors better connection with their family members

Theoretical studies of isolated silicon and germanium clusters, and silicon clusters on Si(111)-7x7 surface

We have performed a systematic search for the ground state geometry of Si+n and Si-n in the size range 3 ≤ n ≤ 20 within the framework of density functional theory (DFT) with the local density approximation (LDA) and generalized gradient approximation (GGA). Various properties such as ionization potentials for neutral clusters, vertical detachment energies and photoelectron spectra for anions, fragmentation pathways and dissociation energies for cations, and mobilities for both anions and cations, are calculated and compared with experiments. The structures for medium-sized clusters (10 ≤ n ≤ 20) generally follow the prolate stacked Si9 tricapped trigonal prism (TTP) pattern. Both bulk silicon and bulk germanium pack in a tetrahedral diamond lattice. Small silicon and germanium clusters with n ≤ 10 also have identical geometries. We performed a systematic ground state search for Gen and Ge+n up to 16 atoms. Like silicon clusters, medium-sized germanium clusters build up by stacking TTP subunits but the global minima for sizes starting from n = 13 differ in details indicating that the growth patterns of silicon and germanium clusters diverge after n = 12. Global minima search for silicon clusters (n = 6--14) on the Si(111)7 x 7 surface were also carried out using both simulated annealing and a genetic algorithm. For n = 6 and n = 7, cluster atoms are anchored to the surfaces to saturate the dangling bonds of the surfaces but the cluster atoms are not bonded together directly. Starting from n = 8, cluster atoms bond together and the clusters begin to grow in three dimensions for n ≥ 13

Strategies for better popularization of new energy vehicles

Presently, energy restrictions are tightening, automotive energy technologies are diversifying, and electric vehicle development and popularity are the largest issues in Japan, the US, Europe, China, and other growing nations. Nonetheless, electric vehicles have been introduced as clean technology since cars were fi rst utilized, but they have not been extensively applied for myriad reasons. By 2025, 12 countries and 25 areas will ban petrol vehicles which need individuals and nations must work together to grow electric vehicle sales. Based on the foregoing, initiatives for better popularization of new energy vehicles will include electronic vehicle technological advancement and national infrastructure with policy support

The production and decay of the top partner TT in the left-right twin higgs model at the ILC and CLIC

The left-right twin Higgs model (LRTHM) predicts the existence of the top partner $T$. In this work, we make a systematic investigation for the single and pair production of this top partner $T$ through the processes: e^{+}e^{-}\to t\ov{T} + T\bar{t} and T\ov{T}, the neutral scalar (the SM-like Higgs boson $h$ or neutral pseudoscalar boson $\phi^{0}$) associate productions e^{+}e^{-}\to t\ov{T}h +T\bar{t}h, T\ov{T}h, t\ov{T}\phi^{0}+T\bar{t}\phi^{0} and T\ov{T}\phi^{0}. From the numerical evaluations for the production cross sections and relevant phenomenological analysis we find that (a) the production rates of these processes, in the reasonable parameter space, can reach the level of several or tens of fb; (b) for some cases, the peak value of the resonance production cross section can be enhanced significantly and reaches to the level of pb; (c) the subsequent decay of $T\to \phi^{+}b \to t\bar{b}b$ may generate typical phenomenological features rather different from the signals from other new physics models beyond the standard model(SM); and (d) since the relevant SM background is generally not large, some signals of the top partner $T$ predicted by the LRTHM may be detectable in the future ILC and CLIC experiments.Comment: 20pages, 15 figures and 6 Tables. Minor corrections on text. new references adde