We give evidence that the all genus amplitudes of topological string theory on compact elliptically fibered Calabi-Yau manifolds can be written in terms of meromorphic Jacobi forms whose weight grows linearly and whose index grows quadratically with the base degree. The denominators of these forms have a simple universal form with the property that the poles of the meromorphic form lie only at torsion points. The modular parameter corresponds to the fibre class while the rôle of the string coupling is played by the elliptic parameter. As a consequence the topological string amplitudes are modular and quasi periodic in the string coupling. This leads to very strong all genus results on these geometries, which are checked against results from curve counting. The structure can be viewed as an indication that an N = 2 analog of the reciprocal of the Igusa cusp form exists that might govern the topological string theory on these Calabi-Yau manifolds completely.

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Poly (MSt-MMA) nanosphere as foam stabilizing agent was synthesized by emulsion polymerization. The three phase foam was prepared with Disodium 4-Dodecyl-2,4′-Oxydiben Zenesulfonate (DOZS) as foaming agent, Hydrolyzed Polyacrylamide (HPAM) and synthesized poly (MSt-MMA) nanospheres as the mixed foam stabilizing agents. It had outstanding foaming performance and foam stability. The optimal three phase foam system consisting of 0.12 wt% HPAM, 0.04 wt% poly (MSt-MMA) nanospheres and 0.12 wt% DOZS by orthogonal experiment, had high apparent viscosity, which showed that three components had a very good synergistic effect. The three phase foam’s temperature tolerance and salt tolerance were researched in laboratory tests. Flooding oil experiment showed that the average displacement efficiency of three phase foam system was 16.1 wt% in single core experiments and 21.7 wt% in double core experiments. Resistance coefficient of low permeability core was more than those of high permeability core, but their residual resistance coefficients were small. The results of core experiment and pilot test indicated that the three phase foam had good profile control ability and generated low damage to the low permeability layer for extra-low permeability reservoirs. Three phase foam flooding has great prospects for Enhanced Oil Recovery (EOR) in extra-low permeability reservoirs.

New electronics, including front-end and data acquisition (DAQ), has been developed and tested for a STAR time-of-flight (TOF) detector based on multi-gap resistive plate chamber (MRPC) technology. The time-over-threshold (TOT), i.e. signal width, is used for the time correction instead of the signal amplitude. Corresponding changes and implementation in the calibration method are discussed in detail. TOF data collected in RHIC 200 GeV Cu+Cu collisions are analyzed to test the performance of the detector. The time resolution is ~75 ps and it is consistent with the results in earlier RHIC runs.

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