Maximum Loading Rate Research Articles

Effects of early sports specialization on landing and balance ability in female college basketball players.

Early specialization in a single sport from childhood is associated with an increased risk for acute and overuse injuries. Conversely, experience in multiple sports may be associated with improved neuromuscular control and performance. Currently, early sports specialization remains poorly researched in Japan. Therefore, this study aimed to clarify the relationship between early sports specialization and landing and balance ability in Japan. Thirty-eight female college basketball players were included and divided into the early specialization and nonspecialization groups. Landing and balance ability was measured using the one-leg jump-landing test, and the Star Excursion Balance Test (SEBT) differences between the two groups were examined using unpaired t-test. Results showed no significant differences in SEBT between the two groups. In the one-leg jump-landing test, the vertical maximum ground reaction force and loading rate of the nondominant foot were significantly higher in the early specialization group than in the nonspecialization group. Thus, in female college basketball players, early specialization may affect ground reaction forces and loading rate and may be a factor in developing acute and overuse injuries.

Gemcitabine-Loaded Microbeads for Transarterial Chemoembolization of Rabbit Renal Tumor Monitored by 18F-FDG Positron Emission Tomography/X-Ray Computed Tomography Imaging

Background/Objectives: The purpose of this study was to develop the gemcitabine-loaded drug-eluting beads (G-DEBs) for transarterial chemoembolization (TACE) in rabbit renal tumors and to evaluate their antitumor effect using 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography/X-ray computed tomography (18F-FDG PET/CT). Methods: DEBs were prepared by polyvinyl alcohol-based macromer crosslinked with N-acryl tyrosine and N,N′-methylenebis(acrylamide). Gemcitabine was loaded through ion change to obtain G-DEBs. Their particle size and drug release profile were characterized. VX2 tumors were implanted in the right kidney of rabbits to establish the renal tumor model. The tumor-bearing rabbits received pre-scan by 18F-FDG PET/CT, followed by targeted transarterial injection of G-DEBs under digital subtraction angiography (DSA) guidance. The rabbits received another 18F-FDG PET/CT scan 10 or 14 days after the treatment. The therapeutic effect was further validated by histopathological analysis of the dissected tumors. Results: The average particle size of the microspheres was 58.06 ± 0.50 µm, and the polydisperse index was 0.26 ± 0.002. The maximum loading rate of G-DEBs was 18.09 ± 0.35%, with almost 100% encapsulation efficiency. Within 24 h, GEM was eluted from G-DEBs rapidly and completely, and more than 20% was released in different media. DSA illustrated that G-DEBs were delivered to rabbit renal tumors. Compared with the untreated control group with increased tumor volume and intense 18F -FDG uptake, the G-DEBs group showed significant reductions in tumor volume and maximum standard uptake value (SUVmax) 10 or 14 days after the treatment. Histopathological analysis confirmed that the proliferating area of tumor cells was significantly reduced in the G-DEBs group. Conclusions: Our results demonstrated that G-DEBs are effective in TACE treatment of rabbit VX2 renal tumors, and 18F-FDG PET/CT provides a non-invasive imaging modality to monitor the antitumor effects of TACE in renal tumors.

Camellia oleifera Abel. shell based slow-release fertilizer: A new insights of urea store and release mechanism from cellular-structural-molecular level

The development of biodegradable slow-release fertilizers derived from lignocellulosic materials is essential for mitigating environmental pollution and ecological damage associated with petroleum-based components in conventional fertilizers, as well as for enhancing agricultural productivity. In this study, a Camellia oleifera Abel. shell based slow-release fertilizer (COSU) was prepared by molten urea impregnation method. FTIR NMR, SEM, EDX, BET and molecular dynamic simulation were used to reveal the urea storage and slow-release mechanisms of COSU at the cell wall and molecular level. These results indicated the role of the cellular tissue structure with its pore structure in the storage and slow release of urea and demonstrate the molecular behavior of urea adsorption and release on lignocellulosic chemical component. The maximum nitrogen loading rate of COSU was 36.58 % and the cumulative release rate over 28 days was 75.08 %, which met the GBT23348–2009 standard. The multiple coupling regulatory mechanism of the cell wall - lignocellulosic molecules of urea store and releasing were discussed and proposed. Pot experiments confirmed that the prepared slow-release fertilizer not only stimulated the growth of corn seedlings but also contributed to an increase in soil humus. The findings of this research provide a new insight and a solid theoretical foundation for the development of lignocellulose-based slow-release fertilizers, offering a sustainable alternative to traditional fertilizers and contributing to a greener agricultural future.

Advancement of constant and progressive load multi‐cycle indentation method on surface properties characterization of polymers

AbstractIn recent years, polymers have been popular in industrial applications due to their lightweight, corrosion‐resistant, improved surface polish, ease of manufacturing, cost‐effectiveness, and so forth. Similarly, micro/nano‐indentation has gained popularity as a technique for assessing the surface mechanical characteristics of polymers. The present study conducted comprehensive experiments using cyclic micro‐indentation on engineering polymers, specifically poly‐ether‐ether‐ketone (PEEK), poly(methyl methacrylate) (PMMA), and poly(tetra‐fluoroethylene) (PTFE). An appropriate and optimal indentation method has been proposed after analyzing the behavior and significance of all the input parameters in evaluating the properties. Both constant load multi‐cycle (CLMC) and progressive load multi‐cycle (PLMC) were considered for this investigation. A comparative evaluation has been conducted to assess two multi‐cycle tests on these materials. From the analysis of the input parameters, including maximum loads, loading and unloading rates, and the number of cycles, the unloading rate and indentation cycle are crucial factors in determining hardness (H) and elastic modulus (E). Increasing the loading rates leads to an increase in H and a reduction in E for all three materials. This effect arises from the thermal effect, which is characterized by the creep modulus and a closed hysteresis loop. Employing the holding duration and multiple cycle data in constant load multi‐cycle can significantly influence the creep behavior and use of the hysteresis loop for fatigue behavior. Similarly, a progressive load multi‐cycle indentation with a force greater than 0.5 N and a minimum of five cycles is the most accurate approach for evaluating surface mechanical parameters.

BIOMECHANICAL INFLUENCE OF RUNNING SHOES WITH MIDSOLE HOLLOW STRUCTURE ON LOWER LIMBS DURING RUNNING

The objective was to investigate the effects of running shoes with midsole hollow structure span and height on the biomechanics of the lower limbs during running. We collected 21 adults with running habits who wore two pairs of running shoes with different midsole hollow structures and ran at a speed of 3.3[Formula: see text]m/s on a force-measuring treadmill. The lower limb kinematics, ground reaction force (GRF) and lower limb muscle activation characteristics were simultaneously captured by a motion capture system, a 3D force treadmill, and a surface electromyography (sEMG) system. Paired t-tests were performed on data for the two shoe conditions that fit the normal distribution assumptions; otherwise, Wilcoxon signed-rank tests were used. The statistical parameter mapping (SPM) technology was used for the analysis of 1D parameters of kinematic, dynamic, and sEMG activation characteristics. The result showed that the time to the peak impact force at touchdown of Hollow shoe2 was significantly increased ([Formula: see text]), the maximum loading rate ([Formula: see text]) and average loading rate ([Formula: see text]) were significantly reduced, braking time ([Formula: see text]), push time ([Formula: see text]), contact time ([Formula: see text]) of Hollow shoe2 were significantly increased compared with Hollow shoe1. Hollow shoe2 push phase of the tibialis anterior muscle activation characteristics was significantly lower (SPM, [Formula: see text]) than Hollow shoe1. Our conclusion is that running shoes offer the solution as they have the advantage of the complex structure of the hollow midsole.

Ethanol-type anaerobic digestion enhanced methanogenic performance by stimulating direct interspecies electron transfer and interspecies hydrogen transfer

Ethanol pre-fermentation of food waste effectively alleviates acidification; however, its effects on interspecies electron transfer remain unknown. This study configured the feed according to COD ratios of ethanol: sodium acetate: sodium propionate: sodium butyrate of 5:2:1.5:1.5 (ethanol-type anaerobic digestion) and 0:5:2.5:2.5 (control), and conducted semi-continuous anaerobic digestion (AD) experiments. The results showed that ethanol-type AD increased maximum tolerable organic loading rate (OLR) to 6.0 gCOD/L/d, and increased the methane production by 1.2–14.8 times compared to the control at OLRs of 1.0–5.0 gCOD/L/d. The abundance of the pilA gene, which was associated with direct interspecies electron transfer (DIET), increased by 5.6 times during ethanol-type AD. Hydrogenase genes related to interspecies hydrogen transfer (IHT), including hydA-B, hoxH-Y, hnd, ech, and ehb, were upregulated during ethanol-type AD. Ethanol-type AD improved methanogenic performance and enhanced microbial metabolism by stimulating DIET and IHT.

Application of Recycled Filling to Improve the Purification Performance of Confectionery Wastewater in a Vertical Anaerobic Labyrinth Flow Bioreactor

Anaerobic wastewater treatment is, in many cases, a justified alternative to typical activated sludge processes, from a technological, economic, and ecological point of view. The optimisation of fermentation reactors is primarily concerned with increasing the biodegradation of organic compounds and biogas production, as well as improving efficiency in the removal of nitrogen and phosphorus compounds. The aim of the research was to determine the impact of using low-cost recycled filling on the efficiency of treating real confectionery wastewater in a vertical anaerobic labyrinth flow bioreactor. The experiments focused on selecting the organic loading rate that would allow for the effective biodegradation and removal of pollutants, as well as the efficient production of biomethane. It was found that the tested reactor can operate efficiently at a maximum organic loading rate (OLR) of 7.0–8.0 g of chemical oxygen demand (COD)/L·d. In this OLR range, high efficiency was guaranteed for both wastewater treatment and biogas production. However, increasing the OLR value to 8.0 g COD/L·d had a significant negative effect on the methane (CH4) content in the biogas. The most efficient variants achieved a biodegradation efficiency of around 90% of the organic compounds, a CH4 content of over 70% in the biogas, and a biogas yield of over 400 L/kg of COD removed. A significant influence of the applied OLR on the ratio of free organic acids (FOS) to total alkaline capacity (TAC) and pH was observed, as well as a strong correlation of these indicators with the specific biogas yield and CH4 content. The application of a solution based on the use of a hybrid system of anaerobic granulated sludge and an anaerobic filter resulted in an efficient treatment process and an almost complete elimination of suspensions from the wastewater.

Subject-specific sensitivity of several biomechanical features to fatigue during an exhaustive treadmill run

The aim of the present study was to examine the sensitivity of several movement features during running to exhaustion in a subject-specific setup adopting a cross-sectional design and a machine learning approach. Thirteen recreational runners, that systematically trained and competed, performed an exhaustive running protocol on an instrumented treadmill. Respiratory data were collected to establish the second ventilatory threshold (VT2) in order to obtain a reference point regarding the gradual accumulation of fatigue. A machine learning approach was adopted to analyze kinetic and kinematic data recorded for each participant, using a random forest classifier for the region pre and post the second ventilatory threshold. SHapley Additive exPlanations (SHAP) analysis was used to explain the models’ predictions and to provide insight about the most important variables. The classification accuracy value of the models adopted ranged from 0.853 to 0.962. The most important feature in six out of thirteen participants was the angular range in AP axis of upper trunk C7 (RTAPu) followed by maximum loading rate (RFDmaxD) and the angular range in the LT axis of the C7. SHAP dependence plots also showed an increased dispersion of predictions in stages around the second ventilatory threshold which is consistent with feature interactions. These results showed that each runner used the examined features differently to cope with the increase in fatigue and mitigate its effects in order to maintain a proper motor pattern.

Enhanced production of <sup>199</sup>Hg cold atoms based on two-dimensional magneto-optical trap

Efficient preparation of cold atoms plays an important role in realizing precision measurement including optical lattice clocks (OLCs). Fast preparation of cold atoms reduces Dick noise by shortening dead time in a clock interrogation cycle, which improves the stability of OLCs. Here, we increase the loading rate of the three-dimensional magneto-optical trap (3D-MOT) in the ultra-high vacuum environment by utilizing the two-dimensional magneto-optical trap (2D-MOT) with a push beam, reduce the temperature of cold atoms with the compression-MOT technique which is implemented by reducing the detuning of 3D-MOT rapidly at the end of atom preparation, and realize the enhanced production of cold atoms for <sup>199</sup>Hg OLCs. To achieve 3D-MOT and 2D-MOT of mercury atoms, a deep ultraviolet laser (DUVL) system composed of three DUVLs is developed with one working in lower power for frequency locking and the other two in high power for laser cooling. Such a configuration improves the long-term frequency stability and shows greater robustness than our previous system consisting of two DUVLs. To maximize the 3D-MOT loading rate, we orderly optimize the detuning and the magnetic field gradient of 3D-MOT and those of 2D-MOT as well as the detuning and the power of the push beam. After all parameters are optimized, we measure the maximum loading rate of 3D-MOT to be 3.1×10<sup>5</sup> s<sup>–1</sup> and prepare cold atoms of 1.8×10<sup>6</sup> in 9 s. The loading rate is greatly enhanced by a factor of 51 by using 2D-MOT and the push beam. In order to improve the efficiency of transferring cold atoms from 3D-MOT to optical lattice, we use compression-MOT technique to reduce the temperature of cold atoms and produce cold <sup>199</sup>Hg atoms which are about 45 μK, lower than the expected temperature of Doppler cooling theory. By achieving the high gain of the 3D-MOT loading rate under the ultra-high vacuum and reducing the temperature of cold atoms, this enhanced preparation of cold atoms based on 2D-MOT effectively shortens the preparation time of cold atoms and improves the transfer efficiency of optical lattice, which provides a significant scheme for efficiently preparing cold mercury atoms in other experiments.

Comparison of the Knee–Thigh–Hip Response in Small Female ATDs with Female PMHS

<div>Bilateral knee impacts were conducted on Hybrid III and THOR 5th percentile female anthropomorphic test devices (ATDs), and the results were compared to previously reported female PMHS data. Each ATD was impacted at velocities of 2.5, 3.5, and 4.9 m/s. Knee–thigh–hip (KTH) loading data, obtained either via direct measurement or through exercising a one-dimensional lumped parameter model (LPM), was analyzed for differences in loading characteristics including the maximum force, time to maximum force, loading rate, and loading duration. In general, the Hybrid III had the highest loading rate and maximum force, and the lowest loading duration and time to peak force for each point along KTH. Conversely, the PMHS generally had the lowest loading rate and maximum force, and the highest loading duration and time to peak force for each point along KTH. The force transfer from the knee to the femur was 79.2 ± 0.3% for the Hybrid III 5th female, 82.7 ± 0.4% for the THOR-05F, and 70.6 ± 1.7% for the PMHS. The force transfer from the knee to the hip was 60.6 ± 0.5% for the Hybrid III 5th female, 41.4 ± 0.4% for the THOR-05F, and 57.0 ± 3.0% for the PMHS. While the Hybrid III aligned more with the PMHS force transfer ratios, the loading characteristics of the THOR-05F were more similar to the PMHS.</div>

Development of hierarchical MOF-based composite phase change materials with enhanced latent heat storage for low-temperature battery thermal optimization

Most of the composite phase change materials (PCMs) based on metal-organic frameworks (MOFs) have much lower latent heat than pure PCMs due to nanoconfined effects, which limits their application in the field of battery insulation. In this work, a series of hierarchical porous carbon nanotubes (CNT)/MOF-199 were synthesized by adjusting the content of N-methyl pyrrolidone (NMP) in the solvent components, and scattered in stearic acid (SA) to obtain a novel composite PCM. The results show that there is a nearly linear relationship between the impregnation ratio, crystallization fraction and impregnation efficiency of PCMs and the mesoporous content of the supporting materials at the maximum loading rate of 70 wt%, which may provide an idea for selecting MOFs supporting materials for PCMs. The latent heat of SA/CNT/MOF-199-2 (SA/CM-2) composite PCM is 97.1/96.2 J·g−1, with a heat loss percentage of only 0.96%. Furthermore, when the lithium-ion battery is discharged 2C at −20 °C, SA/CM-2 used as insulation material can increase the discharge energy by 8.27%. Accordingly, this novel composite PCMs would be hopefully applied to thermal optimization of batteries at low temperatures.

Spatial correlation of the maximum shear strain loading rate and the correlation dimension along the Sumatra subduction margin for potential earthquake and tsunami hazard study and analysis

Spatial correlation of the maximum shear strain loading rate and the correlation dimension along the Sumatra subduction margin for potential earthquake and tsunami hazard study and analysis

Robust BNNS/ANF aerogel skeleton-based PEG composite phase change materials with high latent heat for efficient thermal management

In this work, PEG-based phase change materials with high latent heat were fabricated by integrating ANF with two-dimensional BNNS to create a robust hybrid aerogels skeleton with subsequent PEG impregnation. Specifically, BNNS was initially obtained by boric acid-assisted ball milling, and BNNS/ANF hybrid aerogels were then obtained by freeze-drying. The hybrid aerogel had pores uniformly distributed with a size range of 73–190 μm and exhibited a compressive strength of 28.1 kPa with 50 wt% BNNS. The BNNS/ANF porous skeletons were employed as packaging materials for PEG, offering not only a high-load environment and excellent mechanical support, but also outstanding thermal conductivity. The composite phase change material demonstrated a thermal conductivity of 0.48 W/m·K with 40 wt% BNNS, which was 200 % higher than that of pure PEG. In particular, the rigid BNNS/ANF hybrid aerogels skeleton facilitated PEG storage, achieving a maximum loading rate of 98.73 % and an enthalpy efficiency of 99.87 %, respectively. The phase change enthalpy of the composites was as high as 189.19 J/g. The rigid support and adsorption capabilities of the skeleton structure also improve the shape stability and cycle stability during phase transition. Even after 50 thermal cycles, the phase transition temperature and enthalpy of the composites remained largely unchanged.

Valorization of Dishwashing Scrubber as Biocarrier for the Enrichment of Anammox Bacteria Under Realistic Conditions

The hypersensitivity of anammox bacteria toward fluctuating temperature (seasonal) conditions significantly limits its real-world application. Biomass immobilization alleviates the impact of environmental shocks on the anammox process. In this study (291 d), a sequencing batch reactor engaging dishwashing scrubbers as model waste biocarriers and an amalgamation of activated, anaerobic, and anammox sludge (1:1:0.5 ratio) as inoculum (at influent pH 8.0) were deployed for the startup of the anammox process. Intriguingly, the SBR was run at ambient temperature (6–37 °C) at varying nitrogen loading rates (g N m−3 d−1) of 20, 30, 40, 46.4, 58, 60, 81.2, 92.8, and 116. Notably, anammox activation took place at ⁓247 d wherein the reactor performance improved and exhibited stable nitrogen removal (NH4 +–N, NO2 −–N and total nitrogen removals were 100, 99, and 72.04%, respectively). Additionally, post 279 days of reactor operation (280 – 291 d), the reactor demonstrated an average total nitrogen removal rate (g N m−3 d−1) of 88.2 at a maximum nitrogen loading rate (g N m−3 d−1) of 116. The 16S rRNA gene sequencing results revealed that Anammox bacteria predominated in the reactor, highlighting the fact that the reported increase in the percentage abundance of Candidatus Kuenenia at 266 d was exorbitantly higher (41.69%) than inoculum sludge (0.18%). Nitrospira (23.9%) and Nitrosomonas (4.32%), in addition to anammox, were found in high concentrations, suggesting presence of dissolved oxygen in the system.

Treatment of fresh leachate by anaerobic membrane bioreactor: On-site investigation, long-term performance and response of microbial community

This study proposed fresh leachate treatment with anaerobic membrane bioreactor (AnMBR) based on the on-site investigation of the characteristics of fresh leachate. Temperature-related profiles of fresh leachate properties, like chemical oxygen demand (COD), were observed. In addition, AnMBR achieved a high COD removal of 98% with a maximum organic loading rate (OLR) of 19.27 kg-COD/m3/d at the shortest hydraulic retention time (HRT) of 1.5 d. The microbial analysis implied that the abundant protein and carbohydrate degraders (e.g., Thermovirga and Petrimonas) as well as syntrophic bacteria, such as Syntrophomonas, ensured the effective adaptation of AnMBR to the reduced HRTs. However, an excessive OLR at 36.55 kg-COD/m3/d at HRT of 1 d resulted in a sharp decrease in key microbes, such as archaea (from 37% to 15%), finally leading to the deterioration of AnMBR. This study provides scientific guidance for treating fresh leachate by AnMBR and its full-scale application for high-strength wastewater.

Highly loaded magnetocaloric composites by La(Fe,Si)13H powder dedicated to extrusion-based additive manufacturing applications

Additive manufacturing is attracting increasing interest in the field of magnetic refrigeration to solve the problem of the brittleness of magnetocaloric alloys. The formulation of a composite based on a thermoplastic binder loaded with La(Fe,Si)13H magnetocaloric powder and then its shaping by an innovative additive manufacturing process were investigated in this work. To best preserve the magnetocaloric properties of the powders, the composite must have the highest powder mass fraction and the most suitable rheological behaviour for 3D printing from pellets. The thermo-rheological characterizations of the powders, the constituents of the binders, the binders and the composites were performed. Except for the powder, these behaviours were modelled as a function of the powder's shear rate, temperature and volume fraction leading to the identification of their different parameters. Criteria encompassing more parameters are defined to select the formulation of the composite with its forming parameters (i.e. from its elaboration to its printing). They lead to the selection of a powder, binder and composite components as well as some process parameters that can be optimised (e.g. maximum powder loading rate, nozzle temperature, shear rate). Particular attention is paid to the homogeneity of the composite and the non-degradation of the magnetocaloric properties throughout the fabrication process (i.e. the preservation of hydrogen in the La(Fe,Si)13H powder) which places this work in the context of 4D printing. Different parts (small 0.6 mm thick plates and characterization samples) of highly charged magnetocaloric powder (89% by mass) were printed. Their characterization reveals favourable properties, such as a porosity of 10.8 ± 2% present in the binder (and a global porosity of 5.4 ± 1% in the composite) in the form of pore size <2.10−3 mm3 and with a few voids of 4.10−3 mm3 obtained by X-ray tomography, and, high magnetocaloric properties (Δs = 9.3 J·K−1·kg−1). Other characterizations reveal less favourable mechanical properties, such as a yield strength of 0.7 MPa at room temperature which is highly dependent on the latter rising to an acceptable level of 5 MPa at −20 °C. A comparison with extruded strips of the composite of the same formulation but with lower porosity (i.e. 4% in the binder and overall 2% in the composite) shows an approximately 5-fold higher yield strength and the same initial Young's modulus, which determines the gap for improvement of the overall printing process used in this study.

Preparation and property studies of enteric-soluble oral nattokinase microcapsules with halloysite nanotubes

Eudragit L100-55-halloysite nanotubes (EL100-55, HNTs) nanocomposite microcapsules were introduced to release nattokinase (NK) and avoid the limitations of oral and systemic administration of NK while increasing the entrapment efficiency and stability of NK. The drug loading capacity, stability, and shapes of the NK microcapsules (NK@HNTs-EL) were characterized with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The maximum loading rate of NK was 82.63%, and the encapsulation efficiency of NK was 31.6%. The formulation conditions did not adversely affect the NK tertiary structure. The maximum in vitro drug release in the simulated small intestine buffer was 93.3%, and the NK@HNTs-EL exhibited pH-dependent drug release. The drug release data were analyzed with different kinetic models, which showed that the NK@HNTs-EL drug-release mechanism involved erosion and osmotic pressure on the EL100-55. After 90 days of storage, the NK@HNTs-EL maintained an enzymatic activity greater than 95%. Hemolysis analyses indicated that NK@HNTs-EL was not cytotoxic at concentrations below 500 FU/mL. These findings indicate that NK@HNTs-EL is a promising oral thrombolytic agent.

Continuous single-stage elemental sulfur reduction and copper sulfide precipitation under thermoacidophilic conditions

Metal sulfide precipitation is a viable technology for high-yield metal recovery from hydrometallurgical streams, with the potential to streamline the process design. A single-stage elemental sulfur (S0)-reducing and metal sulfide precipitating process can optimize the operational and capital costs associated with this technology, boosting the competitiveness of this technology for wider industrial application. However, limited research is available on biological sulfur reduction at high temperature and low pH, frequent conditions of hydrometallurgical process waters. Here we assessed the sulfidogenic activity of an industrial granular sludge previously shown to reduce S0 under hot (60–80 °C) and acidic conditions (pH 3.6). A 4 L gas-lift reactor was operated for 206 days and fed continuously with culture medium and copper. During the reactor operation, we explored the effect of the hydraulic retention time, copper loading rates, temperature, and H2 and CO2 flow rates on the volumetric sulfide production rates (VSPR). A maximum VSPR of 274 ± 6 mg·L−1·d−1 was reached, a 3.9-fold increase of the VSPR previously reported with this inoculum in batch operation. Interestingly, the maximum VSPR was achieved at the highest copper loading rates. At the maximum copper loading rate (509 mg·L−1·d−1), a 99.96% copper removal efficiency was observed. 16 s rRNA gene amplicon sequencing revealed an increased abundance of reads assigned to Desulfurella and Thermoanaerobacterium in periods of higher sulfidogenic activity.

Optimization of a Developed Multi-Cyclone Using Response Surface Methodology (RSM) to Control Fine Particulate Emission

The effects of increasing volumetric air flow rate and inlet particulate loading on overall collection efficiency of MR-deDuster; a developed multi-cyclone system was investigated using various segregated sizes of palm oil mill boiler fly ash. The operating conditions of the fabricated pilot plant scale of the unit were predicted theoretically and screened experimentally. Increasing volumetric air flow rate theoretically will increase the overall collection efficiency, yet the experimental results during screening stage demonstrated contradict finding when the increment of volumetric air flow rate caused the overall collection efficiency to be decreased for a constant particulate loading. Subsequently, the optimization work was done to determine the optimum operating conditions of the system using Response Surface Method (RSM) with Box-Behnken design. The parallel arrangement of multi-cyclone units proved the ability of the system to uniformly disseminate the gas flow with high volume of gas carrier. Nevertheless, excessive pressure drops between each unit of multi-cyclone due to high volumetric air flow rate should be avoided as such condition may lower the overall collection efficiency by allowing dust re-entrainment from the hopper to circulate between the cyclones. Through statistical analysis of variance (ANOVA), validation and verification studies, it is suggested that the developed pilot scale multi-cyclone unit would be able to meet the targeted limit of 150 mg/m3 for solid fuel burning equipment industry in Malaysia by operating with optimized volumetric air flow rate of 0.27 m3/s, and maximum inlet particulate loading rate and size of 2 g/m3 and 1000 μm respectively.

Moving Bed Biofilm Reactor Performance on Saline Produced Water (Upstream Oil &amp; Gas) at Very Low Hydraulic Retention Time

This paper presents the results obtained on an oil and gas field terminal in Gabon during a continuous 8-month long operation involving the move of a pre-industrial bed biofilm bioreactor pilot for treating highly saline produced water (100 g/L). After several months of efficient acclimation of the biofilm carriers, more than 90% of the biological oxygen demand, 50% of total organic carbon and 35% of the chemical oxygen demand were removed during 1 h of residence time at a maximum organic loading rate of 12 kgCOD.m−3.day−1, making it a highly promising solution for offshore produced water treatment. These values reached more than 95%, 80% and 60% of BOD, TOC and COD removal, respectively, for 12 h residence time. In addition to the significant removal efficiency of the pilot, it is also important to highlight the robustness of the process. The presence of an acclimated biofilm properly attached to the carriers strongly reduced biomass washing during anomalous phases in comparison to a conventional activated sludge configuration. This technology favorably follows the three key pillars for implementing offshore technologies: high removal performance, robustness and low footprint.