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In this study, we developed a UV-LED/H2O2/Cu2+ system to remove cyanide, which is typically present in metal electroplating wastewater. The results showed the synergistic effects of UV-LED, H2O2, and Cu2+ ions on cyanide removal in comparison with UV-LED photolysis, H2O2 oxidation, UV-LED/H2O2, and H2O2/Cu2+ systems. Cyanide was removed completely in 30 min in the UV-LED/H2O2/Cu2+ system, and its loss followed pseudo-first order kinetics. Statistically, both H2O2 and Cu2+ ions showed positive effects on cyanide removal, but Cu2+ ions exhibited a greater effect. The highest cyanide removal rate constant (k = 0.179 min−1) was achieved at pH 11, but the lowest was achieved at pH 12.5 (k = 0.064 min−1) due to the hydrolysis of H2O2 (pKa of H2O2 = 11.75). The presence of dissolved organic matter (DOM) inhibited cyanide removal, and the removal rate constant exhibited a negative linear correlation with DOM (R2 = 0.987). The removal rate of cyanide was enhanced by the addition of Zn2+ ions (from 0.179 to 0.457 min−1), while the co-existence of Ni2+ or Cr+6 ion with Cu2+ ion reduced cyanide removal. The formation of OH radicals in the UV-LED/H2O2/Cu2+ system was verified using an aminophenyl fluorescence (APF) probe. Cyanate ions and ammonia were detected as the byproducts of cyanide decomposition. Finally, an acute toxicity reduction of 64.6% was achieved in the system within 1 h, despite a high initial cyanide concentration (100 mg/L). In terms of removal efficiency and toxicity reduction, the UV-LED/H2O2/Cu2+ system may be an alternative method of cyanide removal from wastewaters.

Palladium(II) complexes, LnPdCl2 (Ln = LA–LI), with N,N′-bidentate imine ligands derived from picolinaldehyde and substituted anilines have been synthesized and structurally characterized. Molecular structures revealed a distorted square plane geometry around Pd(II) centre in LnPdCl2 (Ln = LA–LC) obtained via coordination with pyridine and imine nitrogens and two chloro ligands. Pd(II) complexes LnPdCl2 (Ln = LA–LI) initiate polymerisation of methylmethacrylate (MMA) in the presence of modified methylaluminoxane (MMAO). The complex LIPdCl2 (of which the ligand was N-furfuryl substituted) showed the highest catalytic activity for the polymerisation of MMA with an activity of 7.08 × 104 g PMMA/mol·Pd·h at 60 °C. All the complexes yielded syndio-rich poly(methyl methacrylate) (PMMA) ([rr] = 0.70). Notably, the substituents on the imine moiety of the iminopyridine fragments affects the activities towards MMA polymerization, whereas the stereoselectivities remained unchanged.

This study was to determine the effect of oleogel on lipid metabolism in rats fed high-fat diet. Male SD rats (n = 32; 4-wk-old) and obese Zucker rats (n = 6) fed either beef tallow containing high fat diet (HFD) or beeswax oleogel containing canola oil (BOG) for 2 months. Substitution of 50% BT by BOG significantly reduced body weight. Increased serum triglyceride by HFD was reduced (P

Rationale and Objectives Although contrast-enhanced ultrasound imaging techniques such as harmonic imaging (HI) have evolved to reduce tissue signals using the nonlinear properties of the contrast agent, levels of background suppression have been mixed. Subharmonic imaging (SHI) offers near complete tissue suppression by centering the receive bandwidth at half the transmitting frequency. The aims of this study were to demonstrate the feasibility of three-dimensional (3D) SHI and to compare it to 3D HI. Materials and Methods Three-dimensional HI and SHI were implemented on a Logiq 9 ultrasound scanner with a 4D10L probe. Four-cycle SHI was implemented to transmit at 5.8 MHz and receive at 2.9 MHz, while two-cycle HI was implemented to transmit at 5 MHz and receive at 10 MHz. The ultrasound contrast agent Definity was imaged within a flow phantom and the lower pole of two canine kidneys in both HI and SHI modes. Contrast-to-tissue ratios and rendered images were compared offline. Results SHI resulted in significant improvement in contrast-to-tissue ratios relative to HI both in vitro (12.11 ± 0.52 vs 2.67 ± 0.77, P P = .04). Rendered 3D subharmonic images provided better tissue suppression and a greater overall view of vessels in a flow phantom and canine renal vasculature. Conclusions The successful implementation of SHI in 3D allows imaging of vascular networks over a heterogeneous sample volume and should improve future diagnostic accuracy. Additionally, 3D SHI provides improved contrast-to-tissue ratios relative to 3D HI.

To demonstrate the feasibility of simultaneous dual fundamental grayscale and subharmonic imaging on a modified commercial scanner.The ability to generate signals at half the insonation frequency is exclusive to ultrasound contrast agents (UCA). Thus, subharmonic imaging (SHI; transmitting at f(0) and receiving at f(0)/2) provides improved visualization of UCA within the vasculature via suppression of the surrounding tissue echoes. While this capability has proven useful in a variety of clinical applications, the SHI suppression of surrounding tissue landmarks (which are needed for sonographic navigation) also limits it use as a primary imaging modality. In this paper we present results using a commercial ultrasound scanner modified to allow imaging in both grayscale (f(0)=4.0 MHz) and SHI (f(0)=2.5 MHz, f(0)/2=1.25 MHz) modes in real time.A Logiq 9 ultrasound scanner (GE Healthcare, Milwaukee, WI) with a 4C curvilinear probe was modified to provide this capability. Four commercially available UCA (Definity, Lantheus Medical Imaging, North Billerica, MA; Optison, GE Healthcare, Princeton, NJ; SonoVue, Bracco Imaging, Milan, Italy; and Sonazoid, GE Healthcare, Oslo, Norway) were all investigated in vitro over an acoustic output range of 3.34 MPa. In vivo the subharmonic response of Sonazoid was investigated in the portal veins of four canines (open abdominal cavity) and four patients with suspected portal hypertension.In vitro, the four UCA showed an average maximum subharmonic amplitude of 44.1±5.4 dB above the noise floor with a maximum subharmonic amplitude of 48.6±1.6 dB provided by Sonazoid. The average in vivo maximum signal above the noise floor from Sonazoid was 20.8±2.3 dB in canines and 33.9±5.2 dB in humans. Subharmonic amplitude as a function of acoustic output in both groups matched the S-curve behavior of the agent observed in vitro. The dual grayscale imaging provided easier sonographic navigation, while the degree of tissue suppression in SHI mode varied greatly on a case by case basis.These results demonstrate the feasibility of dual grayscale and SHI on a modified commercial scanner. The ability to simultaneously visualize both imaging modes in real time should improve the applicability of SHI as a future primary clinical imaging modality.