Integrated Circuit of a Chua's System Based on the Integral-Differential Nonlinear Resistance with Multi-Path Voltage-Controlled Oscillator.

In this paper, we present a fully integrated circuit without inductance implementing Chua's chaotic system. The circuit described in this study utilizes the SMIC 180 nm CMOS process and incorporates a multi-path voltage-controlled oscillator (VCO). The integral-differential nonlinear resistance is utilized as a variable impedance component in the circuit, constructed using discrete devices from a microelectronics standpoint.

Reduction and adsorption of uranium(VI) from aqueous solutions using nanoscale zero-valent manganese.

Nano zero-valent manganese (nZVMn) is theoretically expected to exhibit high reducibility and adsorption capacity, yet its feasibility, performance, and mechanism for reducing and adsorbing hexavalent uranium (U(VI)) from wastewater remain unclear. In this study, nZVMn was prepared via borohydride reduction, and its behaviors about reduction and adsorption of U(VI), as well as the underlying mechanism, were investigated. Results indicated that nZVMn exhibited a maximum U(VI) adsorption capacity of 625.

Corn stalk pith-based hydrophobic aerogel for efficient oil sorption.

Bio-based aerogel has become an attractive sorbent for spilled oil and organic pollutants because of its light weight, high porosity and strong sorption capacity. However, the current fabrication process is mainly "bottom-up" technology, which is cost-expensive, time-consuming, and energy-intensive. Herein, we report a top-down, green, efficient and selective sorbent prepared from corn stalk pith (CSP) using the deep eutectic solvent (DES) treatment, followed by TEMPO/NaClO/NaClO oxidization and microfibrillation, and then hexamethyldisilazane coating.

Thallium removal from wastewater using sulfidized zero-valent manganese: Effects of sulfidation method and liquid nitrogen pretreatment.

Zero-valent manganese (ZVMn) possesses high reducibility in theory, while sulfide exhibits strong affinity towards a variety of heavy metals owing to the low solubility of metal sulfides. Yet the performance and mechanisms on using sulfidized zero-valent manganese (SZVMn) to remove thallium (Tl) from wastewater still remain unclear. In this study, the performance of Tl(I) removal using SZVMn synthesized by borohydrides reduction followed by sulfides modification, with and without liquid nitrogen treatment, was compared and the mechanism behind was investigated.

Efficient removal of antimonate and antimonite by a novel lanthanum-manganese binary oxide: Performance and mechanism.

Antimony is a highly toxic pollutant and its removal from water gains increasing attention. To effectively remove both Sb(III) and Sb(V), a novel lanthanum-manganese binary oxide (LMBO) adsorbent was synthesized by a simple oxidation coupled with precipitation method. The as-prepared LMBO was detailedly characterized by the XRD, SEM, TEM, BET, FTIR and XPS techniques.

Oil/water separation using elastic bio-aerogels derived from bagasse: Role of fabrication steps.

Bio-aerogels hold great promise for selective oil separation from water due to their light weight and high sustainability. However, how the fabrication methods impact the elasticity and oil sorption performance of bio-aerogels still needs systematic comparison and in-depth investigation. In this study, the fabrication of hydrophobic bio-aerogels with good elasticity and reusability was optimized using a factorial design based on the dosages of bagasse-derived cellulose nanofiber, sodium alginate, and calcium carbonate.

Potential application of Fusarium fungal strains (Fusarium sp. FP, Arthrinium sp. FB, and Phoma sp. FR) for removal of Tl (I) ions from water.

Water pollution caused by heavy metals poses a serious threat to the ecosystem and human health. Among the various treatment techniques for water remediation, adsorption is an efficient method due to its high capacity, low cost, and simplicity. Thallium (Tl) is highly toxic to mammals and its removal from water is gaining increasingly prominent attention.

Highly efficient removal of thallium(I) by facilely fabricated amorphous titanium dioxide from water and wastewater.

In this study, amorphous hydrous titanium dioxide was synthesized by a facile precipitation method at room temperature, aiming to effectively remove thallium(I) from water. The titanium dioxide prepared using ammonia as precipitant (TiO) is more effective for thallium(I) uptake than the one synthesized with sodium hydroxide (TiO). The TiO obtained particles are amorphous, aggregates of many nanoparticles and irregular in shape.

Multi-step purification of electrolytic manganese residue leachate using hydroxide sedimentation, struvite precipitation, chlorination and coagulation: Advanced removal of manganese, ammonium, and phosphate.

Water pollution caused by the release of manganese (Mn) and ammonia nitrogen (NH-N) from electrolytic manganese residue (EMR) generated from industrial activities poses a serious threat to ecosystems and human health. In this study, an integrated process consisting sequentially of hydroxide sedimentation, struvite precipitation, breakpoint chlorination, and ferric chloride coagulation was optimized to remove Mn and NH-N from EMR leachate, and to address the issue of residual orthophosphate caused by struvite precipitation. The precipitates were characterized using X-ray diffraction, scanning electron microscopy, and thermogravimetric analyses.

Effective multi-functional biosorbent derived from corn stalk pith for dyes and oils removal.

In this study, malic acid-modified corn stalk pith (MA-CSP) was prepared as an environmentally friendly multi-functional bio-sorbent for adsorbing of dyes and oils. The sorption capacity of the MA-CSP for single and binary dyes is 328.46 mg/g - 566.

Biosorbent with superhydrophobicity and superoleophilicity for spilled oil removal.

The development of efficient and sustainable sorbents for emergent oil cleanup has attracted tremendous attention. In this study, the feasibility of enzymatic grafting of octadecylamine (ODA) on corn stalk pith (CSP) by laccase-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) treatment for enhanced oil-water separation was investigated. The dynamic contact angle tests suggest that the modified CSP (LCSP) had higher hydrophobicity (WCA, 157.

Carbon quantum dots derived from the extracellular polymeric substance of anaerobic ammonium oxidation granular sludge for detection of trace Mn(vii) and Cr(vi).

Carbon quantum dots (CQDs) were synthesized a hydrothermal method, in which extracellular polymeric substance (EPS) from anaerobic ammonium oxidation (anammox) granular sludge was used as a carbon precursor, while citric acid and ethylenediamine were applied as auxiliary carbon source and passivation agent, respectively. The synthesized CQDs, with orderly spherical shape and mean size of 7.15 nm, emitted blue fluorescent light under UV radiation of 365 nm.

Highly efficient removal of thallium(I) from wastewater via hypochlorite catalytic oxidation coupled with adsorption by hydrochar coated nickel ferrite composite.

In this study, tannery wastewater was used as carbon source to hydrothermally synthesize magnetic carbon-coated nickel ferrite composite (NiFeO@C), which was employed as a catalyst for thallium (Tl) oxidation by hypochlorite and simultaneously as an adsorbent for Tl removal from wastewater. Compared with NiFeO@C adsorption or hypochlorite oxidation alone, the combination of NiFeO@C and hypochlorite substantially enhanced the rate and efficiency of Tl(I) removal. In addition, this process was highly effective for Tl(I) removal over a wide pH range (6-12).

Zero-valent iron-manganese bimetallic nanocomposites catalyze hypochlorite for enhanced thallium(I) oxidation and removal from wastewater: Materials characterization, process optimization and removal mechanisms.

Nano zero-valent metals adsorption coupled with advanced oxidation for environmental pollutants removal has been gaining attention recently. In this study, zero-valent iron-manganese (nZVIM) bimetallic nanocomposites were prepared via one-pot borohydride reduction and coupled with hypochlorite (ClO) oxidation for enhanced thallium (Tl) removal from wastewater. Amorphous nZVIM nanoparticles were successfully synthesized, with a specific surface area of 106.

Synthesis of manganese dioxide with different morphologies for thallium removal from wastewater.

Manganese dioxide (MnO) with different morphologies (tube-, wire-, rod-, and flower-like) was synthesized via hydrothermal method and then applied for thallium (Tl) removal from wastewater. During material synthesis, short reaction time (6 h) and low temperature (110 °C) were prone to form polycrystalline flower-like birnessite type MnO, while long reaction time (24 h) and high temperature (240 °C) were inclined to produce polycrystalline wire-like birnessite type MnO. Moderate reaction time (12 h) with low temperature at 120 °C/140 °C led to formation of mono-crystalline rod- and tube-like α-MnO respectively.

Enhanced thallium(I) removal from wastewater using hypochlorite oxidation coupled with magnetite-based biochar adsorption.

The development of efficient and regenerable adsorbent coupled with advanced oxidation for enhanced thallium (Tl) removal has been a recent focus on wastewater treatment. In this study, a magnetite-based biochar derived from watermelon rinds was synthesized and used as a sustainable adsorbent and catalyst for hypochlorite oxidation and removal of Tl(I) from wastewater. The addition of hypochlorite substantially enhanced the Tl(I) removal under normal pH range (6-9).

Mechanism of uranium release from uranium mill tailings under long-term exposure to simulated acid rain: Geochemical evidence and environmental implication.

To date, there is not sufficient knowledge to fully understand the occurrence, transport and fate of residual uranium (U) from uranium mill tailings (UMT). Herein this study investigated different U release behaviors from natural UMT (without grinding) under four simulated acid rain (pH = 2.0-5.

Removal of thallium from aqueous solutions using Fe-Mn binary oxides.

In this study, Fe-Mn binary oxides, which harbor the strong oxidative power of manganese dioxide and the high adsorption capacity of iron oxides, were synthesized for Tl(I) removal using a concurrent chemical oxidation and precipitation method. The adsorption of Tl onto the Fe-Mn adsorbent was fast, effective, and selective, with equilibrium sorption reaching over 95% under a broad operating pH (3-12), and high ionic strength (0.1-0.

Historical trends and ecological risks of polybrominated diphenyl ethers (PBDEs) and alternative halogenated flame retardants (AHFRs) in a mangrove in South China.

While the production of polybrominated diphenyl ethers (PBDEs) was gradually phased out in the last decade, they may still pose hidden danger to the environment due to their toxicity and persistence. On the other hand, alternative halogenated flame retardants (AHFRs) have been increasingly used as substitutes for PBDEs and may further worsen environmental health. To determine the environmental impact of PBDEs and AHFRs, we examined the historical trends and ecological risks of PBDEs and AHFRs in a typical industrialized city in South China by measuring their concentrations in mangrove sediment.

Simultaneous removal of thallium and chloride from a highly saline industrial wastewater using modified anion exchange resins.

Simultaneous removal of thallium (Tl) and chloride from a highly saline industrial wastewater was investigated using modified anion ion exchange resins. The removal of thallium was mainly driven by the exchange of Tl-chlorocomplex (TlCl) formed in the oxidation of thallous (Tl (I)) to thallic ion (Tl (III)) by hydrogen peroxide (HO) under saline conditions. Over 97% of thallium and chloride removal was achieved using the modified resins, with a wide optimal conditions found to be HO dosage 1.

Occurrence of PBDEs and alternative halogenated flame retardants in sewage sludge from the industrial city of Guangzhou, China.

This study investigated the prevalence and abundance of halogenated flame retardants (HFRs) in sludge samples from 5 sewage treatment plants in Guangzhou, China. Detection of 18 polybrominated diphenyl ethers (PBDEs), 9 alternative HFRs including Dechlorane Plus (DP), brominated alkylbenzenes, and polybrominated biphenyls, and 2 related degradation products was conducted. Decabromodiphenyl ether (BDE 209) and decabromodiphenyl ethane (DBDPE) were the dominant HFRs, with concentrations ranging from 200 to 2150 ng/g and 680-27,400 ng/g, respectively.

Characterization and mitigation of nitrous oxide (N2 O) emissions from partial and full-nitrification BNR processes based on post-anoxic aeration control.

It has been reported that a directional change from anoxic to aerobic conditions is a common trigger for nitrous oxide (N2 O) production by ammonia oxidizing bacteria (AOB). By extension, during anoxic-aerobic cycling, post-anoxic dissolved oxygen (DO) concentrations might likely play a role in the magnitude of N2 O emissions observed. The overall goal of this study was to determine the impact of three select post-anoxic DO concentrations (0.

The design and implementation of postprocessing for depth map on real-time extraction system.

Depth estimation becomes the key technology to resolve the communications of the stereo vision. We can get the real-time depth map based on hardware, which cannot implement complicated algorithm as software, because there are some restrictions in the hardware structure. Eventually, some wrong stereo matching will inevitably exist in the process of depth estimation by hardware, such as FPGA.

Long-term performance and microbial ecology of a two-stage PN-ANAMMOX process treating mature landfill leachate.

Long-term performance of a two-stage partial nitritation (PN)-anaerobic ammonium oxidation (ANAMMOX) process treating mature landfill leachate was investigated. Stable partial nitritation performance was achieved in a sequencing batch reactor (SBR) using endpoint pH control, providing an effluent with a ratio of NO2(-)-N/NH4(+)-N at 1.23 ± 0.

Transformation of metals speciation in a combined landfill leachate treatment.

Landfill leachate was treated by a combined sequential batch reactor (SBR), coagulation, Fenton oxidation and biological aerated filter (BAF) technology. The metals in treatment process were fractionated into three fractions: particulate and colloidal (size charge filtration), free ion/labile (cation exchange) and non-labile fractions. Fifty percent to 66% Cu, Ni, Zn, Mn, Pb and Cd were present as particulate/colloidal matter in raw leachate, whereas Cr was present 94.