Facile Process Research Articles

Unveiling the potential of a g-C3N4/BiOBr/Bi2O2CO3 ternary heterojunction photocatalyst for rechargeable zinc-air battery: Visible-light-driven photo-assisted charging for bifunctional ORR and OER at the air cathode

Advancements in solar-driven energy storage technology have been achieved for rechargeable zinc-air batteries (RZABs), facilitating accelerated kinetic responses in both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this study, we successfully synthesized a novel g-C3N4/BiOBr/Bi2O2CO3 ternary heterojunction through a facile hydrothermal process, demonstrating its efficacy as a bifunctional photocatalyst. Upon exposure to LED irradiation, this heterojunction triggers an effective separation of the photogenerated electron-hole pairs, resulting in enhanced oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance by 46.19 % and 65.69 % respectively, compared to non-LED conditions. Interestingly, the reduction in the potential gap under LED irradiation (0.06 V), correlating with a significant 2.71 % increase in round-trip efficiency (RTE), is observed. In addition, the optimized band alignment derived from g-C3N4/BiOBr/Bi2O2CO3 ternary heterojunction for photo-assisted charging rechargeable zinc-air batteries is proposed. Insightfully, photo-enhanced charging in RZABs mechanism during the charge/discharge process through in-situ X-ray absorption spectroscopy (XAS) is monitored, confirming the large interaction between O2 adsorption and Bi 6d orbitals of g-C3N4/BiOBr/Bi2O2CO3 in the presence of LED. In conclusion, our innovative g-C3N4/BiOBr/Bi2O2CO3 ternary heterojunction underscores the significant role that visible-light-driven photocatalysts can play in enhancing the efficiency of rechargeable zinc-air batteries.

Up-scaling Social Innovations: The Eku and Implications for Enhancing Small-scale Palm Oil Production in Nigeria

The dearth of adoption of processing technologies by small-scale palm oil processors in Nigeria has resulted in poor quality of output and low extraction rates. This paper proposes that improved versions of the Eku, a community-based social innovation which enables the sharing of palm oil processing facilities can be up-scaled and diffused in the sector to improve the technological base of small-scale palm oil production in Nigeria. A framework, which emphasises removing constraints to the practicality and efficiency of social innovations with institutional and funding measures to create a prototype that will be up-scaled and diffused, is developed. The study reveals that only one of five unit operations of small-scale palm oil production is totally mechanised in the Eku and constraints affecting full mechanisation of all unit operations in the Eku include lack of awareness and funds to adopt processing technologies. The chapter recommends equipping prototype Ekus with innovations for all the un-mechanised stages of palm oil production and suggests its up-scaling and diffusion in the sector through small-scale entrepreneurs. The study concludes that the diffusion of the prototype versions of the Eku can enhance the diffusion of technological innovations in the sector.

Modulation of electronic structure of Ni3S2 via Fe and Mo co-doping to enhance the bifunctional electrocatalytic activities for HER and OER

Heazlewoodite nickel sulfide (Ni3S2) is advocated as a promising nonnoble catalyst for electrochemical water splitting because of its unique structure configuration and high conductivity. However, the low active sites and strong sulfur–hydrogen bonds (S–Hads) formed on Ni3S2 surface greatly inhibit the desorption of Hads and reduce the hydrogen and oxygen evolution reaction (HER and OER) activity. Doping is a valid strategy to stimulate the intrinsic catalytic activity of pristine Ni3S2 via modifying the active site. Herein, the Ni foam supported Fe and Mo co-doped Ni3S2 electrocatalysts (Fe-MoS2/Ni3S2@NF) have been constructed using Keplerate polyoxomolybdate {Mo72F30} as precursor through a facile hydrothermal process. Experimental results certificate that Fe and Mo co-doping can effectively tune the local electronic structure, facilitate the interfacial electron transfer, and improve the intrinsic activity. Consequently, the Fe-MoS2/Ni3S2@NF display more excellent HER and OER activity than MoS2/Ni3S2@NF and bare Ni3S2@NF by delivering the 10 and 50 mA cm−2 current densities at ultra-low overpotentials of 74/175 and 80/160 mV for HER and OER. Moreover, when coupled in an alkaline electrolyzer, Fe-MoS2/Ni3S2@NF approached the current of 10 mA cm−2 under a cell voltage of 1.60 V and exhibit excellent stability. The strategy to realize tunable catalytic behaviors via foreign metal doping provides a new avenue to optimize the water splitting catalysts.

스프레이 프린팅된 1 V 이하의 유연한 전해질 게이트 인버터

We demonstrate all-printed, low-voltage, and flexible electrolyte-gated transistors and inverters prepared through a facile spray-printing process. All active components of the electronic circuits, including source/drain electrodes, semiconductor, gate dielectric, gate electrode, and load resistor, were directly deposited via spray printing. The sprayed transistors show a high on/off ratio of ∼104. The printed devices also show excellent operational stability under successive bending stresses, maintaining 88% of their performance after 5,000 bending cycles at a small bending radius of 2 mm. Furthermore, the resistor-loaded flexible inverters exhibit appropriate rail-to-rail voltage inverting characteristics with a high voltage gain of ~9 at a low supply voltage of −1 V. These results demonstrate that the high-throughput strategy is promising for generating low-voltage, flexible, and all-spray-printed electronic circuits.

Mapping the processes and information flows of a prehospital emergency care system in Rwanda: a process mapping exercise

ObjectiveA vital component of a prehospital emergency care system is getting an injured patient to the right hospital at the right time. Process and information flow mapping are recognised methods...

Experimental study on responsiveness of multi-spectrum infrared flame detectors to diffuse flames partially hidden by obstacles installed in oil and gas processing facilities

Multi-spectrum infrared flame detectors are commonly installed in many oil and gas processing facilities for an early fire detection. Since these facilities are filled with equipment and piping, the visibility of flames from infrared flame detector is a critical factor for reliable and early detection. However, conventional methodology of fire mapping study does not consider the three-dimensional spread of flames. Therefore, this paper focuses on the responsiveness of multi-spectrum infrared flame detectors under the condition that flame is partially hidden by such obstructions.A series of full-scale experiments was conducted to examine the responsiveness of infrared flame detectors to flames partially hidden by shielding objects. These experiments simulated various conditions seen in the oil and gas processing facilities.The experiments have confirmed the relationship between the intensity of infrared energy and the obstruction ratio. Specifically, the infrared energy at a wavelength of 4.504 μm emitted from a flame hidden by shielding objects can be quantified using the obstruction ratio, the ratio of visible area of partially hidden flame. By using these indices, it has been clarified that the infrared energy emitted from a partially hidden flame at the location of an infrared flame detector can be estimated. The responsiveness of detectors depends more on the intensity of the infrared energy near 4.5 μm than on flame pulsation. Multi-spectrum flame detectors, commercially available and employed in this study, exhibited performance equal to or even more sensitive than what is stated in their data sheets. Quantitative evaluation of the responsiveness of flame detectors to partially hidden flames revealed in this study can contribute to the improvement of the fire mapping study for the realistic design evaluation in the oil and gas processing facilities.

Effect of MWCNTs surface functionalization on the characterization of PVA/MWCNTs nanocomposites

The present study aims to put forward the role of surface functionalization of multi-walled carbon nanotubes (MWCNTs) on the enhancement thermal and hydrophilicity properties of new nanocomposite based poly(vinyl alcohol)/surface functionalized MWCNTs (PVA/MWCNTs), prepared by a facile phase inversion process. In this study, the fabrication of PVA/MWCNTs nanocomposites is carried out using functionalized MWCNTs (f-MWCNTs) with different functional groups (–OH, –COOH, –NH2). The structural, morphological, thermal, hydrophilicity and physico-chemical properties of PVA/MWCNTs nanocomposites are characterized by XRD, FE-SEM, FT-IR, TGA and contact angle measurement. The FT-IR results confirm the formation of a hydrogen bond between MWCNTs and PVA chain. XRD analysis indicates an improvement in the crystallinity of the PVA/MWCNTs nanocomposite. TGA results reveal that the PVA/f-MWCNTs nanocomposites show higher thermal stability than pure PVA. It is revealed that PVA/MWCNTs nanocomposites based functionalized MWCNTs remarkably increase the degradation temperature, and thus enhancing the thermal properties. The highest weight loss (30.7 wt%) and degradation temperature (520 °C) values are obtained with PVA/f-MWCNTs(0.5 wt%). The contact angle measurement confirms that the hydrophobic properties of pure PVA became hydrophilic because of the functional groups of MWCNTs. The hydrophilicity of PVA/MWCNTs nanocomposites is increased with the increase in wt% of MWCNTs embedded in the nanocomposite.

Soft Schottky diodes for skin-interfaced electronics enabled by entirely soft components

Soft electronics have achieved significant development, attracting substantial interest due to their promising potential as a dominant form of future electronics. In this rapidly evolving field, the fully soft Schottky diode plays a critical role as a fundamental building block for electronic circuitry systems. These systems, constructed entirely from soft materials, can tolerate various mechanical deformations when interfaced with human skin, making them ideal for use in health monitoring systems and interactive human-machine interfaces. In this study, we introduce a Schottky diode fabricated entirely from soft materials using a facile solution process, further enabling all-printing fabrication systems. Utilizing the mechanical softness of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate-based soft electrode, poly(3-hexylthiophene) nanofibril composite soft semiconductor, and liquid metal, we successfully fabricated a fully soft Schottky diode. This diode exhibits exceptional electrical characteristics even under various mechanical deformations, showcasing the high durability of the device. We have further developed fully soft rectifiers and logic gates, highlighting the versatility of our study. By incorporating these devices with a piezoelectric nanogenerator in a skin-interfaced energy harvesting system, they exhibit sufficient capability for rectification, ensuring a stable power supply as part of a power supply management system. This approach offers substantial potential for future skin-interfaced electronics, paving the way for advanced wearable technology.

Is the persistence of Listeria monocytogenes in food processing facilities and its resistance to pathogen intervention linked to its phylogeny?

The foodborne pathogen Listeria monocytogenes is differentiated into four distinct lineages which differ in their virulence. It remains unknown, however, whether the four lineages also differ with respect to their ability to persist in food processing facilities, their resistance to high pressure, a preservation method that is used commercially for Listeria control on ready-to-eat meats, and their ability to form biofilms. This study aimed to determine differences in the pressure resistance and biofilm formation of 59 isolates of L. monocytogenes representing lineages I and II. Furthermore, the genetic similarity of 9 isolates of L. monocytogenes that were obtained from a meat processing facility over a period of 1 year and of 20 isolates of L. monocytogenes from food processing facilities was analyzed to assess whether the ability of the lineages of L. monocytogenes to persist in these facilities differs. Analysis of 386 genomes with respect to the source of isolation revealed that genomes of lineage II are over-represented in meat isolates when compared with clinical isolates. Of the 38 strains of Lm. monocytogenes that persisted in food processing facilities (this study or published studies), 31 were assigned to lineage II. Isolates of lineage I were more resistant to treatments at 400 to 600 MPa. The thickness of biofilms did not differ between lineages. In conclusion, strains of lineage II are more likely to persist in food processing facilities while strains of lineage I are more resistant to high pressure.IMPORTANCEListeria monocytogenes substantially contributes to the mortality of foodborne disease in developed countries. The virulence of strains of four lineages of L. monocytogenes differs, indicating that risks associated with the presence of L. monocytogenes are lineage specific. Our study extends the current knowledge by documentation that the lineage-level phylogeny of L. monocytogenes plays a role in the source of isolation, in the persistence in food processing facilities, and in the resistance to pathogen intervention technologies. In short, the control of risks associated with the presence of L. monocytogenes in food is also lineage specific. Understanding the route of contamination L. monocytogenes is an important factor to consider when designing improved control measures.

Association of liver-abscess presence and severity with trim loss, slaughter yield, carcass grading performance, lung lesions, and value of fed-Holsteins*

ObjectiveOur objective was to evaluate the effects of liver abscesses on carcass characteristics and value of Holstein carcasses. Materials and MethodsFed-Holsteins were evalu- ated at 2 commercial processing facilities in Texas (n = 1,073) and Kansas (n = 1,070) from fall of 2016 through spring of 2017. Liver abscesses were visually assessed and scored; simultaneously, lungs were manually palpated to assess degree of consolidation and fibrin tag formation, to assess their association with liver abnormality. Finally, carcass trim was weighed from carcasses moved off line for zero tolerance trimming. Carcass and viscera values were assigned using USDA market reports and adjusted based on viscera condemnations along with premiums and dis- counts for quality and yield outcomes. Data were analyzed using the MIXED and GENMOD procedures of SAS v9.4 (SAS Institute Inc., Cary, NC) with carcass as the experi- mental unit. Results and DiscussionHot carcass weight was re- duced (−25.1 kg, −6.6%) in carcasses that had an ad- hered and open liver abscess as compared with carcasses without abscessed livers. Carcasses with adhered, open, or adhered and open liver scores had increased carcass trim (0.72, 3.92, and 3.39 kg, respectively) when compared with carcasses without abscessed livers (0.38 kg). Similarly, carcasses with adhered, open, or adhered and open liver scores returned gross carcass revenues that were 5.0% to 6.4% less (–$97.69, –$93.86, and –$121.22/carcass, re- spectively) than carcasses without abscessed livers. Liver abscesses reduced gross offal values of individual animals by 20% to 84% depending upon severity. Implications and ApplicationsFed-Holsteins have been a significant portion of the beef industry, even though Holsteins have increased rates of severe liver ab- scesses compared with their non-dairy-reared equivalents. Therefore, methods to control liver abscesses should be employed, to mitigate the greater financial risk that Hol- steins and dairy-reared animals incur to both cattle feeders and beef processors.

Facile Preparation Method of TiO2/Activated Carbon for Photocatalytic Degradation of Methylene Blue.

The development of nanocomposite photocatalysts with high photocatalytic activity, cost-effectiveness, a simple preparation process, and scalability for practical applications is of great interest. In this study, nanocomposites of TiO2 Degussa P25 nanoparticles/activated carbon (TiO2/AC) were prepared at various mass ratios of (4:1), (3:2), (2:3), and (1:4) by a facile process involving manual mechanical pounding, ultrasonic-assisted mixing in an ethanol solution, paper filtration, and mild thermal annealing. The characterization methods included XRD, SEM-EDS, Raman, FTIR, XPS, and UV-Vis spectroscopies. The effects of TiO2/AC mass ratios on the structural, morphological, and photocatalytic properties were systematically studied in comparison with bare TiO2 and bare AC. TiO2 nanoparticles exhibited dominant anatase and minor rutile phases and a crystallite size of approximately 21 nm, while AC had XRD peaks of graphite and carbon and a crystallite size of 49 nm. The composites exhibited tight decoration of TiO2 nanoparticles on micron-/submicron AC particles, and uniform TiO2/AC composites were obtained, as evidenced by the uniform distribution of Ti, O, and C in an EDS mapping. Moreover, Raman spectra show the typical vibration modes of anatase TiO2 (e.g., E1g(1), B1g(1), Eg(3)) and carbon materials with D and G bands. The TiO2/AC with (4:1), (3:2), and (2:3) possessed higher reaction rate constants (k) in photocatalytic degradation of methylene blue (MB) than that of either TiO2 or AC. Among the investigated materials, TiO2/AC = 4:1 achieved the highest photocatalytic activity with a high k of 55.2 × 10-3 min-1 and an MB removal efficiency of 96.6% after 30 min of treatment under UV-Vis irradiation (120 mW/cm2). The enhanced photocatalytic activity for TiO2/AC is due to the synergistic effect of the high adsorption capability of AC and the high photocatalytic activity of TiO2. Furthermore, TiO2/AC promotes the separation of photoexcited electron/hole (e-/h+) pairs to reduce their recombination rate and thus enhance photocatalytic activity. The optimal TiO2/AC composite with a mass ratio of 4/1 is suggested for treating industrial or household wastewater with organic pollutants.

The removal of microplastics from reverse osmosis wastewater by coagulation

Wastewater treatment plants (WWTPs) are major sources of microplastic (MP) discharge into water bodies, leading to plastic pollution in the environment and negative effects on aquatic ecosystems. Research is increasingly being focused on MP removal from wastewater, as their presence in freshwater environments, and associated risks, are matters of growing concern. Eliminating MPs from wastewater is a significant challenge for WWTPs, and mitigation actions are required to develop and improve removal treatments. Coagulation has been shown to have high removal efficiency for suspended particles, including MPs. This process involves the addition of coagulants, such as aluminum or iron salts that together with the MPs form larger flocs, facilitating their removal by settling or flotation. Our study evaluated the coagulation process, aiming to improve MP removal from wastewater generated from reverse osmosis (RO) concentrate, backwash microfiltration (MF), and cleaning chemicals for membranes operated by MF and RO processes in industrial water supply facilities. More than 1000 MP particles, predominantly polymers with polyethylene (PE), polypropylene (PP), and polystyrene (PS) were identified as being influenced by the current process. We used polyaluminum chloride (PAC) as chemical coagulant to evaluate MP removal during batch experiments (jar test). Our coagulation process achieved higher efficiencies for microplastic removal than conventional biological treatment processes at an optimal PAC dose and pH. Remarkable results were obtained, with more than 90% of MPs being removed. Our findings indicate that chemical coagulation is effective for removing MPs, and that the process could be optimized by selecting an appropriate coagulant and pH.

Facile one-step synthesis of in situ WO3@Gr nanorods as an efficient material for antimicrobial and decoloration applications

This work examined the synthesis, antibacterial activity, and decolourisation of WO3@Graphene nanorods (WO3@Gr NR). WO3@Gr NR nanocomposite was in situ produced via a facile one-step hydrothermal process employing sodium tungstate dihydrate and exfoliated graphene as precursors. The resulted NR exhibited an average diameter of 13 nm, a large specific surface area of 53.3 m2 g−1, and a bimodal pore size distribution with an average pore size of 5.5 nm. The optical bandgap is extrapolated to be 2.75 eV. Graphene was shown to be responsible for the sample’s elaborate visible-light absorption, which improved adsorption and the ability to harvest visible light. WO3@Gr NR are more efficient against E. coli than S. aureus, killing up to 52% and 39% of cells, respectively, after two hours of treatment. When used in conjunction with invisible light, the NR killed E. coli and S. aureus by 78 and 62%, respectively. The bactericidal activity of photoinduced WO3@Gr NR was evaluated against P. aerugunosa, E. faecalis, E. coli, and S. aureus. The photocatalytic constant rates of organic dye methylene blue (MB) were determined to be 0.01 min−1. An IC50 (50% cell growth inhibition) value of 97 (μg ml−1) was determined for the nanocomposite against human liver cancer cell lines (HepG2). Our findings suggest that this nanorod may be utilised to degrade bacteria and organic colours in wastewater simultaneously while posing no risk to human health.

Constructing hierarchical CuS hollow spheres as efficient anode for aqueous zinc-ion batteries

In recent years, aqueous zinc-ion batteries (ZIBs) have emerged as a prominent research topic due to their inherent safety attributes, relatively low cost, and comparatively higher energy density. However, the challenges associated with the zinc metal anode in the form of dendrite formation, hydrogen evolution, and severe side reactions have proven to be particularly vexing. Thus, it is imperative to investigate novel intercalation-type anode materials for ZIBs that exhibit exceptional structural properties and appropriate redox potentials based on conversion mechanisms. In this work, through adding polyvinylpyrrolidone (PVP) surfactant to precursors and tailoring reaction time, hierarchical CuS hollow spheres are successfully constructed by a facile one-step hydrothermal process. When applied as an anode in ZIBs, the hollow hierarchical CuS with large surface area can effectively reduce the transport distance of electrons and Zn2+ and alleviate volume expansion during the insertion/extraction of Zn2+. The hierarchical CuS hollow spheres prepared over 8 h (CuS-8) exhibit a specific capacity of 126 mAh/g and long-term cycle life (1500 cycles) at a current density of 3 A/g. In addition, CuS-8//MnO2@CNTs full-cell shows a capacity retention of 117 mAh/g after 300 cycles at 1 A/g current density, which proves the advantage of hierarchical CuS hollow spheres in serving as an efficient and durable anode material for ZIBs.

Shielding design and analysis of the hot cell used to produce fission molybdenum-99

Molybdenum-99 is a critical radioisotope for producing diagnostic radiopharmaceuticals labeled by technetium-99m. In this study, the shielding of hot cells used in radiochemical process facilities for industrial 99Mo production via fission of domestic LEU targets was investigated. A calculation method based on MCNP6 simulations was proposed and evaluated by some experimental data. The results showed that the calculated dose rate values should be multiplied by 1.3 from a conservative point of view and then values compared with the permissible dose rate limits. The ISODOSE graphs showed that although a one-layer hot cell with Barite concrete (BA) walls of 80 cm is not enough for radiation-safe work on a hot batch, a one-layer hot cell of BA with 90 cm walls, two-layer BA(80 cm) + Lead(3 cm) and BA(80 cm) + Carbon steel (CS) (4.3 cm) and three-layer BA(80 cm) + CS(1.4 cm) + Lead(2 cm) could be suitable options.

Hierarchical multiphase heterointerfaces Ni2P–CoP/MoO2 catalyst for efficient and stable hydrogen evolution reaction over the entire pH range

The development of pH-versatile, high-performing, and durable catalysts for hydrogen evolution reaction (HER) is crucial to satisfy the complex environment of water electrolysis industry. Herein, we present the synthesis of a hierarchical multiphase heterointerfaces Ni2P–CoP/MoO2 nanocatalyst with exceptionally high HER activity in the entire pH range through a facile three-step process involved hydrothermal, electrodeposition, and in situ phosphating treatment. Experiments and characterization revealed the strong electronic interactions among the phases of Ni2P, CoP, and MoO2, which endowed the Ni2P–CoP/MoO2 with high hydrogen evolution activity in different pH ranges. Meanwhile, the layered structure of our as-prepared catalyst makes the massive exposure of active sites. As a result, the Ni2P–CoP/MoO2 catalyst shows remarkable performance, requiring mere overpotentials of 33, 41, and 23 mV to drive 10 mA cm−2 in 1 M KOH, 1 M phosphate buffer solution, 0.5 M H2SO4, respectively. Moreover, the catalyst exhibits excellent stability in the chronopotentialmetry test under different pH electrolyte. Impressively, the Ni2P–CoP/MoO2 catalyst coupled with Ni–Fe LDH to form an overall water splitting system only require 1.50 V to drive 10 mA cm−2. Furthermore, this system actuated by wind and solar energy can stably undergo a continuous production of hydrogen and oxygen.

Fabrication of hydrophilic cellulose graft copolymer/SiO2 coated mesh for efficient oil-water separation

A superhydrophilic and underwater superoleophobic cellulose graft copolymer/SiO2 coated metal mesh (CASi/M) was fabricated through a facile and cost-effective process. As-prepared CASi/M could separate different oil-water mixture with a separation efficiency higher than 99.4 % and a flux up to 26940 L·m−2·h−1 only driven by gravity. The reusability experiment showed that the separation efficiency still exceeded 99.2 % after 25 cycles, which displayed superior reusability. Furthermore, CASi/M displayed superior stability in corrosive liquids such as acidic, alkaline, and salty environments. This work provides new sights in the development of durable and low-cost functional materials for rapid and efficient oil/water separation.

Effect of Season and Machine Type on Performance of Semi- and Fully Mechanized Harvesting Systems in Beech-Dominated Stands

It is common to have large trees in mature hardwood-dominated stands. This is especially true for European beech (Fagussylvatica L.), which can also have a complex architecture. Such trees have predominantly been harvested using motor-manual operations. However, in an effort to increase occupational safety and allow for a more continuous wood flow to processing facilities, fully-mechanized systems are also being employed more frequently. This study was established to determine the effect of season (Fall or Winter) and harvester type (wheeled or tracked) on the performance of semi- and fully- mechanized harvesting systems deployed in beech-dominated stands. Time-and-motion analysis was conducted on a total of 927 trees located in two forest sites in Germany. The study indicated that new silvicultural prescriptions make it impossible to harvest all trees exclusively with mechanized systems, even in the case of the tracked harvester with its 14.5 m boom. Motor-manual intervention was needed with trees that were too large, malformed or out of reach. Motor-manual intervention was significantly more frequent for the wheeled (30%) than for the tracked harvester (18%). Once again, tree size had the strongest effect on time consumption in a linear model, which varied from 0.5 to over 6 min per tree. Season and machine effect were also significant but could only account for a small fraction of the total variability. For the same tree size, time consumption was higher with the wheeled harvester and during the fall. The model also indicated a significant relationship between tree form and time consumption, even though the explanatory contribution of this independent variable was relatively small, too. Good stem form resulted in a lower time consumption. The larger tracked harvester was generally more efficient, but also more expensive to own and operate: its higher costs must be weighed against the higher revenues. New silvicultural trends make it difficult to achieve full mechanization, but the results of this study may guide managers towards technical solutions that minimize motor-manual intervention to the advantage of higher productivity and better occupational safety.

Synthesis of Cu doped NiO for their antioxidant and photocatalytic properties: Green synthesis using Lycopodium Linn

Metal oxide nanoparticles produced by plant extracts are more stable and biocompatible in comparison with those produced by physical and chemical methods. This research focuses on the synthesis of pure and Cu doped NiO nanoparticles (NPs) using Phytolacca dodecandra L'Herit (P.d) leaf extract and evaluation of their antioxidant and photocatalytic activities. The obtained Cu-doped NiONPs have been characterized through X-ray diffraction (XRD), Transmission electron microscope (TEM), Fourier transform infrared (FT-IR), Ultraviolet-visible (UV–Vis), N2 adsorption-desorption and X-ray photoelectron spectra (XPS) analyses in different concentrations (1, 3, and 5 %) of copper at an optimum temperature of 400 °C. The photocatalytic activity of prepared samples was studied by degradation of Rose Bengal (RB) and Methylene Blue (MB) dye aqueous solutions. Under UV radiation for 60 min. 5-Cu-NiO nanophotocatalyst showed degradation efficiency of 98.7 % (0.5 mol/L), high apparent constant (0.9871 min−1) and long term stability towards MB dye. In the antioxidant test, NiO NPs and Cu−NiO NPs prevented the oxidation of 50 % of the H2O2 molecules at a concentration of 363.96 and 350.29 μg/mL, respectively. Moreover, the enhancement of the antioxidant activity of the biosynthesized NiO NPs might be an effect of copper ions present in the particles. Facile and green synthesis process with the excellent degradation performance demonstrates that the Cu doped NiO NPs have a great potential for wastewater treatment applications.

Effect of Crude Oil Spillage and Constraints Associated with Artisanal Fishing in Oil-Spilled Areas of Bayelsa State

This study considered the effect of crude oil spillage and constraints associated with artisanal fishing in oil-spilled areas of Bayelsa State. The study's goals were to find out the respondents' socioeconomic status, determine how the spill of crude oil affected artisanal fishing, and pinpoint the obstacles to artisanal fishing output in particular oil-spilled areas. A simple random selection technique was employed to select 100 respondents, from whom a questionnaire was used to collect data for the study. Descriptive statistics were used to analyze the data that was collected. Men made up the majority of respondents (77%), according to the study's main findings. In the region where crude oil spilled, 55% of the artisanal fishermen were between the ages of 45 and 55. Married respondents made up 84% of the sample, and 60% had finished secondary school. The respondents had a mean of 25.4 years of experience and an average household size of 6. The main obstacles to artisanal fishing in the areas affected by the spill of crude oil were the following: water pollution, rising consumption, lack of government support, issues with marketing, spoiled fish, funding and credit issues, absence of extension services, climate change and flooding, poor processing facilities, high labour costs, health issues, and a scarcity of fishing baits. This study makes several recommendations, including better processing facilities, increased access to bank loans at lower interest rates for farmers, expanded and strengthened extension services, and the establishment of policies by the government, private citizens, and corporate entities that will boost output and improve the profitability of artisanal fishing.