Topological phases and fractional excitations of the exciton condensate in a special class of bilayer systems

We study the exciton condensate in zero temperature limit in a special class of electron-hole bilayer systems adjacent to insulating ferromagnetic films. With the self-consistent mean-field approximation, we find that the Rashba spin-orbit interaction in the electron and hole layers can induce the p \pm ip or p pairing states depending on the different magnetization of the overlapped ferromagnetic films. Correspondingly, the topologically nontrivial or trivial phases emerge. Furthermore, in the topologically nontrivial phase, the quasiparticle excitations of the U(1) vortex are attached to fractional quantum numbers and obey Abelian statistics.Comment: 7 pages, 5 figure

Exciton condensation and fractional charge in a bilayer two-dimension electron gas adjacent to a superconductor film

We study the exciton condensate (EC) in a bilayer two-dimension-electron-gas (2DEG) adjacent to a type-II superconductor thin film with an array of pinned vortex lattices. By applying continuum low energy theory and carrying numerical simulations of lattice model within mean-field approximation, we find that if the order parameter of EC has a vortex profile, there are exact zero modes and associated \emph{rational} fractional charge for zero pseudospin potential ($\mu$) and average chemical potential ($h$): $\mu$=0 and $h$=0; while for $\mu\mathtt{\neq}0$ and $h$=0, intervalley mixing splits the zero energy levels, and the system exhibits \emph{irrational} fractional \emph{axial} charge.Comment: 4.6 pages, 3 figure

Suppressed star formation in circumnuclear regions in Seyfert galaxies

Feedback from black hole activity is widely believed to play a key role in regulating star formation and black hole growth. A long-standing issue is the relation between the star formation and fueling the supermassive black holes in active galactic nuclei (AGNs). We compile a sample of 57 Seyfert galaxies to tackle this issue. We estimate the surface densities of gas and star formation rates in circumnuclear regions (CNRs). Comparing with the well-known Kennicutt-Schmidt (K-S) law, we find that the star formation rates in CNRs of most Seyfert galaxies are suppressed in this sample. Feedback is suggested to explain the suppressed star formation rates.Comment: 1 color figure and 1 table. ApJ Letters in pres

Dust Obscuration in Lyman Break Galaxies at z~4

Measuring star formation rates (SFRs) in high-z galaxies with their rest-frame ultraviolet (UV) continuum can be uncertain because of dust obscuration. Prior studies had used the submillimeter emission at 850 um to determine the intrinsic SFRs of rest-frame UV selected galaxies, but the results suffered from the low sensitivity and poor resolution (~15''). Here, we use ultradeep Very Large Array 1.4 GHz images with ~1''-2'' resolutions to measure the intrinsic SFRs. We perform stacking analyses in the radio images centered on ~3500 Lyman break galaxies (LBGs) at z~4 in the Great Observatories Origins Deep Survey-North and South fields selected with Hubble Space Telescope/Advanced Camera for Surveys data. The stacked radio flux is very low, 0.08+/-0.15 uJy, implying a mean SFR of 6+/-11 M/yr. This is comparable to the uncorrected mean UV SFRs of 5 M/yr, implying that the z~4 LBGs have little dust extinction. The low SFR and dust extinction support the previous results that z~4 LBGs are in general not submillimeter galaxies. We further show that there is no statistically significant excess of dust-hidden star-forming components within ~22 kpc from the LBGs.Comment: 6 pages, 3 figures, and 2 tables. Accepted to the Astrophysical Journal (ApJ

MICROWAVE-ASSISTED ANALYTICAL METHODS FOR RAPID SOLIDS AND WATER CONTENT DETERMINATION

Wang, MHS and Wang, LK (2021). Microwave-assisted analytical methods for rapid solids and water content determination. In: "Environmental Science, Technology, Engineering, and Mathematics (STEM)", Wang, LK, Wang, MHS, and Pankivskyi, YI (editors). Volume 2021, Number 11, November 2021; pp.31. Lenox Institute Press, Auburndale, Massachusetts,USA. ......ABSTRACT: The authors introduce the microwave-assisted methods as a stepping-stone of environmental research, hoping that (a) operators may use the microwave-assisted methods as the supplemental analytical methods for analyzing the TS, TSS, TDS, and water content under urgent situations and with a standard operating procedure (SOP) for the microwave oven to be used; (b) researchers may develop more similar microwave-assisted technologies for various environmental applications; (c) this microwave-assisted solids and water content methods may one day become a part of the Standard Methods; and (d) the laboratory equipment manufacturers are willing to produce high quality, programmable, and temperature controllable microwave facilities for environmental applications in the near future. Current Standard Methods are: (a) Method 2540B TS dried at 103-105 oC; (b) Method 2540C TDS dried at 180 oC; and Method 2540D TSS dried at 103-105 oC. The Standard Methods allows a material balance calculation among the three solids (TS = TSS + TDS) if two solids are known. The authors suggest that the testing temperatures for the three closely related solid tests, (TS, TSS, and TDS) be consistent, either all 103-105 oC, or all 180 oC, in order to avoid any errors

REMOVING HIGH COLOR OF HUMIC SUBSTANCES OR NEUTRALIZING ACIDITY OF ACID RAIN BY FLOTATION-FILTRATION WATER TREATMENT SYSTEM

(A) The first part of this paper demonstrates the feasibility of a DAF-filtration water treatment system for removal of humic substances and 400 color units from a contaminated water. Trihalomethanes are primarily formed by the reaction of free chlorine with humic substances, such as humic acid and fulvic acid, called trihalomethane precursors. A raw water containing 21.5 mg/L of humic acid, 400 units of color and 9 NTU of turbidity was treated by the continuous pilot plant. Over 94 percent of humic acid, 99 percent of color and 93 percent of turbidity were removed when 9.26 mg/L of alum in terms of Al2O3 was dosed as coagulant at pH 6.5. .......(B) The second part of this paper demonstrates the feasibility of the same DAF-filtration system skid-mounted on a boat for neutralization of acidity in lake water caused by acid rain. High acidity in lake water is primarily formed by dissolution of industrial air pollutants such as, sulfur dioxide (SO2), nitrogen oxides (NOx) , etc. which are carried by rains to lake water. Actual acidic lake water from Florida-MA having pH 4.9, color 3.5 units, turbidity 2.8 NTU, acidity 24 mg/L as CaCO3, nitrate nitrogen 0.4 mg/L, phosphate 0.1 mg/L as P, sulfate 70 mg/L and total coliforms 160 /100 mL was treated by the same pilot plant continuously for 5 hours under the same operational conditions but using 4.4 mg/L of sodium aluminate as Al2O3 and 3.5 mg/L of calcium hydroxide. It was discovered that DAF alone would be sufficient for acid rain neutralization, but the added filtration step would produce an effluent meeting the drinking water standards in terms of pH, color, turbidity, phosphorus, and coliforms

One-dimensional anyons with competing δ\delta-function and derivative δ\delta-function potentials

We propose an exactly solvable model of one-dimensional anyons with competing $\delta$-function and derivative $\delta$-function interaction potentials. The Bethe ansatz equations are derived in terms of the $N$-particle sector for the quantum anyonic field model of the generalized derivative nonlinear Schr\"{o}dinger equation. This more general anyon model exhibits richer physics than that of the recently studied one-dimensional model of $\delta$-function interacting anyons. We show that the anyonic signature is inextricably related to the velocities of the colliding particles and the pairwise dynamical interaction between particles.Comment: 9 pages, 2 figures, minor changes, references update

SUSTAINABLE WATER AND WASTEWATER TREATMENT SYSTEMS CONSISTING OF MAGNESIUM COAGULATION-PRECIPITATION, DISSOLVED AIR FLOTATION, RECARBONATION AND FILTRATION

Advancements of new process systems consisting of magnesium coagulation-precipitation, dissolved air flotation (DAF) clarification, filtration and disinfection are introduced : (a) the use of magnesium carbonate or magnesium chloride for replacing alum, (b) the use of DAF for replacing sedimentation, (c) the use of magnesium coagulation-precipitation, DAF , recarbonation , and filtration for water or wastewater treatment, (d) production and marketing of magnesium and calcium sludge for replacing conventional lime as the soil conditioner or for nutrient removal in a biological treatment plants. Examples and case histories of the sustainable process system include: (a) magnesium coagulant for water purification with total chemical sludge recycle; (b) independent physicochemical wastewater treatment using magnesium coagulant and DAF-filtration for treating wastewaters containing toxic substances; (c) simultaneous removal of ammonium ions and phosphate ions from wastewater by magnesium ions for generating useful waste sludge (Struvite) which can be reused as a fertilizer; (d) chemical sludge reuse elsewhere for toxic chromium reduction; (e) waste chemical sludge reuse for biological nitrification neutralization at chicken and meat processing plants; (f) waste chemical sludge reuse for anaerobic digestion improvement at bakeries; (g) pretreatment of per- and polyfluoroalkyl substance (PFAS) contaminated water prior to granular activated carbon, ion exchange, or membrane filtration; and (h) production and marketing of combined magnesium and calcium sludge as a soil conditioner. The authors' poem ( FATE IN THIS LIFE 今世缘) is presented in this publication

COOLING TOWER AND BOILER WATER TREATMENT TERMINOLOGIES

Wang, MHS, and Wang, LK (2022). Cooling tower and boiler water treatment terminologies. In: "Environmental Science, Technology, Engineering, and Mathematics (STEM)", Wang, LK, Wang, MHS, and Pankivskyi, YI (editors). Volume 2022, Number 2, February 2022; 76 pages. Lenox Institute Press, MA, USA. ISBN 978-0-9890870-3-2............ABSTRACT: There has been a special partnership of the United Nations Industrial Development Organization (UNIDO) and the US Environmental Protection Agency (USEPA) for transferring the US new and well-established technologies to the developing countries and disseminating the useful technical information to the entire world. This publication is one of many technology transfer documents prepared by the Lenox Institute of Water Technology (LIWT). It introduces the UNIDO, USEPA, LIWT, and the cooling tower and boiler water treatment terminologies. The terminology subjects cover the following areas: the types of cooling tower and boiler, water treatment systems, evaporation, make-up water, blowdown, drift, leakage, cycle of concentrations, ton of refrigeration, water quality parameters, water quality standards, operational problems, scale, biofilm, fouling, corrosion, inhibitors, chemical treatment, non-chemical physical water treatment, physicochemical treatment, green innovations, operation and management (O&M), O&M optimization, water recycle, and water reuse considerations

LAKE POLLUTION PREVENTION AND RESTORATION USING ELECTROFLOTATION AND FILTRATION

This publication identifies lake eutrophication, its biochemical process, causes, effects, prevention, lake restoration, available technologies (electroflotation, dissolved air flotation and filtration), etc. Two continuous pilot plant studies were conducted: (a) treatment of septic tank effluent along lake shoreline by electroflotation-filtration (EFF) and drainfield for lake pollution prevention; and (b) treatment of Stockbridge Bowl water by EFF for lake restoration. The new technologies were jointly developed by the Lenox Institute of Water Technology (LIWT) and Krofta Engineering Corporation (KEC). For lake pollution prevention, a septic tank effluent was successfully treated to meet the NPDES effluent discharge permit requirements. For lake restoration, Stockbridge Bowl water was successfully treated in terms of high % removal of phosphate-P (100%), TSS (100%), COD (71%), color (95%), turbidity (90%), aluminum (58%), and algae or particle counts (99.7%), etc. The authors also discuss other lake pollution prevention and restoration methodologies: such as property awareness, on-site septic effluent clarification, in-lake restoration (aeration, chemical precipitation, etc.), barge mounted flotation treatment plants, algae harvesting for energy production, and lake acid rain reversal etc. Although only the LIWT-KEC technologies were used for the feasibility studies, another manufacturers' equivalent process equipment is expected to produce similar performance data, if their process equipment is optimized. For lake applications, the equipment foot-print must be small and the overall costs must be affordable. Continuous pilot plant demonstration of any manufacturer's process equipment is highly recommended. This publication is one of many professional memoirs being written by the authors