Silver nanoparticle-decorated NiFe2O4/CuWO4 heterostructure electrocatalyst for oxygen evolution reactions.

In this work, Ag nanoparticles decorated with NiFe2O4/CuWO4 heterostructure were synthesized using the step-wise precipitation method. The influence of varying Ag loading on the NiFe2O4/CuWO4 heterostructure and its electrochemical OER performance was extensively studied in 1 M KOH electrolyte. The obtained LSV profile was analyzed to determine the overpotential, Tafel slope, and onset potential. The heterostructure with an optimal Ag loading of 5 wt% required the least overpotential (1.60 V vs. RHE) for generating a current density of 10 mA cm-2 with a lower Tafel slope of 44.5 mV dec-1, indicating its faster OER kinetics. Furthermore, the composite remained stable over a period of 24 hours with a minimum rise in the overpotential after the stability test. The enhanced OER performance of the as-prepared catalyst can be attributed to the presence of multiple metallic elements in the Ag-loaded NiFe2O4/CuWO4 composite, which created a diverse array of oxygen-vacant sites with varying reactivity, enhancing the charge-transfer kinetics; and thus contributing to the overall efficiency of OER. Therefore, optimizing the Ag concentration and engineering a microstructure represents an encouraging strategy for developing cost-effective catalysts for next-generation energy-conversion applications.

Waste remediation: Low-temperature synthesis of hybrid Cu(OH)2/CuO and CuO nanostructures from spent printed circuit boards and their dye degradation studies.

The demand for environmentally friendly and sustainable resource utilization techniques for recycling waste printed circuit boards is significant due to their status as valuable secondary resources, containing high-purity copper and precious metals. In this context, Cu(OH)2/CuO and CuO nanostructures were fabricated using alkaline precipitation and low-temperature aging methods using the strip solution originated from laboratory-scale spent mobile phone printed circuit board recovery process. XRD, FTIR, FESEM-EDX, and TEM were utilized to characterize the as-recovered nanoproducts. A hybrid structure of Cu(OH)2/CuO was formed at 70°, and monoclinic CuO phase was formed at 80 °C aging time. The results show that Cu(OH)2/CuO nanoflakes have an average crystallite size of 24.06 nm and a particle width of 22 ± 3 nm. Cu(OH)2/CuO nanoflakes formed at 70 °C aging temperature and 24-h residence time have finer crystallite and particle sizes than CuO-ridged nanospheres formed at 80 °C aging temperature. The optical band gap energy of Cu(OH)2/CuO and CuO nanostructures formed was found to be 2.28 eV and 2.22 eV, respectively. The hybrid Cu(OH)2/CuO nanostructure photocatalyzed the decomposed 97.28% rhodamine blue using a visible light source, whereas the CuO nanostructure degraded only 14.64% rhodamine blue dye under similar conditions. A surfactant-less hybrid structure is developed without the use of any chemical precursor. Thus, a high value-added product is produced using one waste material to remove another waste in wastewater treatment.

Genesis of copper oxide nanoparticles from waste printed circuit boards and evaluation of their photocatalytic activity.

Discarded Printed Circuit Boards (PCBs) are one of the secondary resources of high-purity copper, and precious materials, which if disposed off inappropriately may present several environmental risks. This study focuses on the production of copper oxide nanoparticles (CuO NPs) from reclaimed copper via a facile precipitation route to obtain a value-added nanoproduct. The synthesis involved the dissolution of downsized PCBs, leaching of Cu into the solution phase and the precipitation of nanoparticles (NPs) in an alkaline medium. XRD analysis confirmed the as-synthesized NPs were monoclinic CuO of size 19.23 nm without any impurity. HRTEM analysis confirmed that the NPs were nearly round spheres with average particle size of 19.973 ± 6.036 nm. The NPs have a specific surface area of 200 m2/g and mesoporous structure with mean pore diameter of 18.051 nm. The CuO NPs photocatalyzed the degradation of Congo Red under visible light irradiation. Hence, the PCB e-waste was utilized to produce nanomaterials with added-values, decreasing environmental problems.

The bandgap of sulfur-doped Ag2O nanoparticles.

A narrow band gap restricts photocatalytic applications of Ag2O nanoparticles, but appropriate doping can favorably modify this aspect. Given this, density functional theory (DFT) calculations were conducted, revealing that substitutional sulfur doping of Ag2O could increase its bandgap and stabilize oxygen vacancies. A hydrothermal precipitation protocol was employed to prepare sulfur-doped (S-doped) Ag2O nanoparticles. The band gap of the prepared nanoparticles increased to 1.89 eV with 1.25-mole percent S-doping. XPS analysis of the samples also revealed that S-doping increased oxygen vacancies in the prepared Ag2O nanoparticles. Furthermore, S-doping caused a major shift in the valence band position to a negative value. These doped Ag2O nanoparticles showed an enhanced visible-light photocatalytic activity towards rhodamine B (RhB) degradation.

Synthesis and characterization of titanium-substituted nanocrystalline Co2-Y hexaferrite: magnetically retrievable photocatalyst for treatment of methyl orange contaminated wastewater.

Rapid industrial growth causes considerable environmental havoc, adversely affecting human and aqueous life. It becomes a significant concern to deal with adequate wastewater treatment strategies by converging on water scarcity. This research work explored the synthesis of titanium-substituted Y-type barium hexaferrite (Co2-Y), having a general formula of Ba2Co2Fe12-xTixO22 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5), using a facile nitrate-based sol-gel auto-combustion route and its suitability was investigated as a heterogeneous catalyst within the photo-Fenton-based degradation of methyl orange (MO), one of the significant pollutants generated from textile industries. Developing a thermochemically stable and magnetically separable heterogeneous catalyst for photocatalytic decomposition of nonbiodegradable organic dye from wastewater was also emphasized. The as-prepared nanocrystalline Co2-Y powders were analyzed using XRD, FTIR, DLS, UV-visible spectroscopy, SEM, VSM, and XPS. Furthermore, the photocatalytic degradation performance of pristine and titanium substituted Ba2Co2Fe11.6Ti0.4O22 ferrite, having the lowest bandgap value among all samples, was quantified and compared in terms of apparent rate constant (karc) value and turnover frequency values. The enriched photocatalytic performance was correlated with the existence of multi-valance states of transition metal cations and the availability of oxygen vacancy, confirmed by the surface chemistry using the XPS analysis. The modified (enhanced thermal and chemical stability) hexaferrite catalyst was magnetically separable and reusable without significant losses to its catalytic performance. This promising catalyst may be considered as a replacement for soft ferrite materials to catalyze the degradation of several other nonbiodegradable organic pollutants from wastewater in large-scale industries.

Does Time of Administration of Intravenous Ketorolac Impact Pain-Related Outcomes in Dacryocystorhinostomy?

PURPOSE: An emerging body of evidence indicates that intravenous ketorolac (IVK) reduces pain scores and the requirement for opioid analgesics in a variety of oculofacial procedures. This study was performed to assess the impact of timing of IVK administration on these benefits after external dacryocystorhinostomy (DCR). METHODS: Patients were randomized to receive IVK before (n = 50), during (n = 50), or after DCR (n = 50). An additional cohort of control patients did not receive the medication (n = 50). Postoperative pain was measured via a visual analog scale immediately after DCR on the first day after surgery (POD1). Additionally, the need for opioid analgesics to control pain was recorded. Statistical analyses were performed via a dedicated computerized software package. RESULTS: Immediately after surgery, mean pain scores were 5.26 for control patients, and 2.30, 2.44, and 2.36 for patients that received IVK pre-, intra-, and post-operatively, respectively (p < .001 for each condition, as compared to controls). On POD1, mean pain scores were 3.52 for control patients and 1.38, 1.32, and 1.28 for patients that received IVK pre-, intra-, and post-operatively, respectively (p < .001 for each condition, as compared to controls). 28% of control patients required postoperative opioid analgesics, as compared to 6%, 4%, and 4% among patients that received IVK pre-, intra-, and postoperatively, respectively (p < .05 for each condition, as compared to controls). CONCLUSIONS: IVK significantly reduces postoperative pain and the requirement for opioid analgesics after DCR, regardless of the timing of administration. This benefit appears to extend into the first postoperative day.

Cd-doped Ag2O/BiVO4 visible light Z-scheme photocatalyst for efficient ciprofloxacin degradation.

Foreign element doping can produce new photocatalysts with different band edge positions and adsorption properties. A composite of such a doped semiconductor with another component should enhance its photocatalytic properties towards a target substrate. The present investigation used a simple hydrothermal protocol to prepare Cd-doped Ag2O nanoparticles. The Cd-doping of Ag2O nanoparticles changed its valence band maximum position from 0.8 eV (for undoped Ag2O nanoparticles) to 2.67 eV with a slight narrowing of the Ag2O bandgap. A combination of DFT calculation and XRD results showed that the dopant Cd substituted Ag in the Ag2O lattice. The doped material is an effective photocatalyst for ciprofloxacin degradation but with poor recyclability. The joining of a BiVO4 part to the Cd-doped Ag2O nanostructures gave a composite with improved photocatalytic activity and recyclability towards ciprofloxacin degradation. DFT calculations showed that BiVO4 has a higher oxygen affinity than Cd-doped Ag2O. The XPS characterization of the composite and appropriate active species scavenger experiments demonstrated a Z-scheme mechanism. Superoxide radicals play a critical role in CIP degradation.

AgI/CuWO4 Z-scheme photocatalyst for the degradation of organic pollutants: Experimental and molecular dynamics studies.

While the knowledge of the adsorption properties of components of a composite heterogeneous photocatalyst is critical to its applicability to a particular reaction, there has been little research in this direction. The present research is on the development of AgI/CuWO4 nanocomposites that photocatalytically degraded ciprofloxacin and rhodamine B in an aqueous medium under visible light irradiation. The nanocomposites were prepared by a step-wise precipitation protocol. XPS analysis and active species trapping experiments demonstrated that the photocatalysis proceeded by a Z-scheme mechanism. Large scale aqueous medium molecular dynamics simulations showed that oxygen and CIP adsorb on the AgI part, while water interacts intensely with the CuWO4 component. Information from experimental and molecular dynamics studies was combined to arrive at the photocatalysis mechanism.

Foot and Mouth Disease (FMD) incidence in cattle and buffaloes and its associated farm-level economic costs in endemic India.

The study investigated the important epidemiological parameters and farm-level economic costs of FMD incidence in cattle and buffaloes during 2013-14 to 2015-16 in various states of India. Multistage random sampling procedure was adopted for the primary survey and data was collected through face-to-face personal interview from 18,609 cattle and buffalo rearing farm households from 123 districts across twelve states and one Union Territory. Besides epidemiological parameters, different farm-level direct and indirect loss associated with FMD was assessed at disaggregated level (states) by employing deterministic mathematical models. Highest number of affected villages and disease incidence was observed in non- FMD control programme (FMD-CP) implemented Madhya Pradesh and Assam states, respectively whereas negligible incidence was in FMD-CP implemented Punjab state. The disease incidence was high during 2013-14 and declined during 2014-15 and 2015-16, respectively implied severe incidence scenario (2013-14) succeeded by moderate (2014-15) and mild (2015-16) scenarios. The crossbred and high productive animals were severely affected than local breeds whereas on sexwise and agewise comparison revealed higher incidence in females and adult animals. During severe incidence scenario, milk loss/animal ranged from USD 6.87-47.44, 18.42-125.88, 16.33-91.43, and 27.17-123.62; mortality loss/animal ranged from USD 32.61-804.27, 30.76-577.7, 65.36-502.2, and 188.04-413.7; distress sale loss/animal ranged from USD 3.22-188.63, 64.34-519.3, 214.47-341.8, and 209.11-450.3; and opportunity cost of labour/animal from USD 5.49-54.29, 5.49-67.78; 7.95-31.37 and 9.83-72.38 in indigenous cattle, crossbred cattle, local and improved buffalo, respectively. The estimated draught power loss/animal varied from USD 39.46-142.94 with least being in Madhya Pradesh and highest in Assam states whereas the median treatment cost/animal was USD 9.18 and USD 27.07 in indigenous cattle and upgraded buffaloes, respectively. The total farm-level economic loss projected due to FMD in cattle and buffaloes in India was USD 3159 million (INR 221,110 million), USD 270 million (INR 18,910 million) and USD 152 million (INR 10,610 million), respectively during the severe, moderate and mild incidence scenarios at 2015-16 constant prices. The loss varied across the states, and in severe incidence scenario, the country might lose USD 3.2 billion/year and hence, the bi-annual vaccination schedule need to be strictly implemented in all the states. Besides timely vaccination coverage, managing unabated animal movement, educating and motivating the farmers to vaccinate their animals might reduce the incidence and consequential losses to various stakeholders in endemic states like India.

Intravenous Ketorolac Reduces Pain Score and Opioid Requirement in Orbital Surgery.

PURPOSE: Intravenous ketorolac (IVK) is an effective agent to reduce postoperative pain without the risks inherent to opioid analgesics. However, many clinicians avoid using this agent due to concerns regarding hemorrhagic complications. This study was performed to assess the efficacy and safety of IVK in the setting of orbital surgery. METHODS: In a single dose prospective study, patients either received IVK immediately before orbital surgery (n = 50) or acted as controls (n = 50). Postoperative pain was evaluated via a numerical scale (range = 0-10) immediately after surgery, before discharge to home, and on the first postoperative day (POD1). The requirements for opioid analgesic and anti-emetic medications were determined by the nursing staff and recorded. Statistical analyses were performed via a dedicated software package. RESULTS: Fifty patients received IVK (24 males, 26 females, mean age = 54 years, SD = 18 years) and 50 patients acted as controls (26 males, 24 females, mean age = 50 years, SD = 19 years) immediately before orbital surgery. Mean pain scores were lower in patients who received IVK than in controls immediately after surgery (3.08 vs. 5.44, p = 0.0001) and on POD1 (1.04 vs. 2.66, respectively, p = 0.0001). Four patients (8%) who received IVK and 12 patients who did not (24%) required opioid analgesics to control pain (p = 0.03). No patient experienced a hemorrhagic complication or required an emergent return to the operating room. CONCLUSIONS: In the setting of orbital surgery, IVK safely and effectively reduces pain and the requirement for opioid analgesics. Within the limits of the study size, increased risks of bleeding-related complications were not identified.

Preoperative Intravenous Ketorolac Safely Reduces Postoperative Pain in Levator Advancement Surgery.

PURPOSE: To assess the impact of intravenous ketorolac (IVK) on self-reported pain scores, requirements for opioid analgesic and anti-emetic medications, and bleeding complications in the setting of levator advancement surgery METHODS:: A prospective randomized controlled trial was performed among adult patients undergoing levator advancement surgery. Pain scores were measured immediately after surgery, prior to discharge from the surgical facility, and on the first postoperative day. The requirements for postoperative analgesic and anti-emetic medications were recorded. Statistical comparisons were performed via a dedicated computerized software package. RESULTS: Fifty patients (20 males, 30 females, mean age = 65.7 years, standard deviation = 11.9 years) underwent levator advancement without IVK and acted as controls. An additional 50 patients received IVK (19 males, 31 females, mean age = 64.6 years, standard deviation = 12.0 years). As compared with control patients, IVK resulted in statistically significant reductions in pain score immediately after surgery (4.62 vs. 1.44, p = 0.0001) and on postoperative day 1 (3.22 vs. 1.24, p = 0.0001). Fourteen patients (28%) in the control and 4 patients (8%) in the group that received IVK required opioid analgesics (p = 0.017). Seven patients (14%) in the control group and 1 patient in the group that received IVK required anti-emetic medications (p = 0.059). No patient experienced a hemorrhagic complication. CONCLUSIONS: In the setting of levator advancement surgery, IVK results in a dramatic reduction in self-reported pain score immediately after surgery and on postoperative day 1 and the requirement for opioid analgesics. This medication may be safely utilized for ptosis repair.

Intravenous Acetaminophen in Orbital Surgery.

PURPOSE: To assess the role of intravenous acetaminophen (IVA) in orbital surgery. METHODS: Fifty control patients underwent orbital surgery without IVA. Fifty patients received 1 g of IVA within 30 minutes of surgery, and 50 patients received 1 g of IVA immediately preoperatively. Postoperative requirements for analgesic and anti-emetic medications and standardized pain scores were recorded. RESULTS: 44 patients (88%) in the control group and 57 patients (57%) that received IVA preoperatively required analgesic medications (p = 0.0023). 31 patients (62%) that received the medication within 30 minutes of surgery and 26 patients (52%) that received IVA immediately preoperatively required analgesic medications (p = 0.77). The control group had a greater requirement for analgesic medications than patients that received IVA within 30 minutes of orbital surgery (p = 0.0076) and those that received IVA immediately preoperatively (p = 0.032). Twelve patients in the control group (24%) and 4 patients (4%) in the group that received IVA preoperatively received anti-emetic medications (p = 0.0078). Mean pain scores for all patients that received IVA, patients that received IVA within 30 minutes of surgery, and patients that received IVA at the time of surgery were 3.68 (standard deviation = 3.24), 3.12 (standard deviation = 3.05) and 4.39 (standard deviation = 3.37), respectively, as compared to a mean control group score of 7.92 (standard deviation = 3.36), (p = 8.30x10). CONCLUSIONS: When administered prior to orbital surgery, IVA significantly reduced pain scores and postoperative requirements for analgesic and anti-nausea medications.