The unprecedent prevalence of digitalization has an impact on learning modules, particularly with the shift from print modules to e-modules. Though there is amount of research dedicated to English ...learning modules, research on e-modules for EFL/ESL learning is still scarce. Hence, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines is used to guide the selection, screening, and reporting processes. The research objective is to synthesize the available literature, present the current stances of EFL/ESL learning e-modules, and identify gaps thoroughly scrutinizing documents from 2000 to February 2024. Three databased including Web of Science (WOB), Scopus and ERIC were reviewed, only with 15 articles meeting the inclusion criteria. The findings indicated that EFL/ESL learning e-modules were mostly related with two themes, namely English for specific purpose (ESP) and learner autonomy. Based on the findings, the review puts forward suggestions and gaps for future research.
Multiple antibiotics that are used in veterinary medicine coexist in soils, but their interaction and the effects on adsorption and desorption in soils have not been extensively studied. In this ...study, using batch experiments, we evaluated the adsorption and desorption of sulfadiazine (SDZ), tetracycline (TC), and norfloxacin (NFX) using four different soil aggregate size fractions and discovered that: (1) TC had the highest adsorption (76–98 %) and the lowest desorption in each tested system, whereas SDZ showed opposite adsorption and desorption ability, (2) the highest adsorption and the lowest desorption of all three tested antibiotics were observed with soil macroaggregates (250–2000 µm) in all the cases; in contrast, opposite adsorption and desorption ability were observed for soil clay (<53 µm), and (3) adsorption of each antibiotic was in the following order: single system (71–89 %) > binary system (56–84 %) > ternary system (50–78 %); however, desorption were in the reverse order. The Freundlich equation fitting and Brunauer–Emmett–Teller (BET) analysis further demonstrated that the adsorption competition between the tested antibiotics depended mainly on the specific surface area of each soil aggregate size fractions and its chemical properties. In conclusion, soil macroaggregates play a key role in the retention of antibiotics in soils, and the coexistence of multiple antibiotics greatly increases leaching risk.
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•Soil macroaggregates (250–2000 µm) showed the highest adsorption rate and the lowest desorption rate for the tested antibiotics.•The adsorption rates of the antibiotics were in the following order: tetracycline > norfloxacin > sulfadiazine.•The adsorption capacity of each antibiotic was in the following order: single system > binary system > ternary system. This is mainly attributed to the number of available adsorption sites.•Brunauer–Emmett–Teller (BET) analysis showed that the specific surface area of each soil component affects the adsorption of antibiotics.
Cesarean has been suggested to decrease neonatal iron stores at birth. However, few studies have differentiated the effect induced by cesarean operation from that related to medical indications.
We ...aimed to estimate the association of cesarean delivery on maternal request (CDMR), a subtype of cesarean without any medical indications, with a spectrum of indicators reflecting iron stores at birth.
This prospective cohort study involved 288 term singleton neonates born to women without any complications by CDMR or spontaneous vaginal delivery (SVD). Measured hematological iron-related indicators in cord blood included serum ferritin (SF), hemoglobin (Hb), red blood cell (RBC), and hematocrit (Hct). Blood flow volume (BFV) of cord vein when clamping was measured to reflect placental transfusion status during birth. Quantile regression was used to assess the association between delivery mode and the iron store indicators.
CDMR (n = 154) versus SVD group (n = 134) had lower conditional median cord blood SF (-34.80; 95% CI -64.70, -4.90 μg/L; P = 0.02), Hb (-10.67; 95% CI -18.87, -2.47 g/L; P = 0.01), RBC (-0.30; 95% CI -0.48, -0.12 ×10
/L; P = 0.002), and Hct (-3.06; 95% CI -6.08, -0.04 %; P = 0.047). The BFV was higher in CDMR than SVD group at the 25th centile (0.51; 95% CI 0.19, 0.82 ml/cm
; P = 0.002), median (0.49; 95% CI 0.04, 0.95 ml/cm
; P = 0.03) and the 75th centile (0.54; 95% CI 0.06, 1.03 ml/cm
; P = 0.03).
The cesarean operation per se likely hampered placental transfusion from mother to neonate and decreased iron stores at birth.
The aim of this study was to characterize the effects of cornstalk biomass amendments on microbial communities in bauxite residues (BRs) by phylogenetic analysis. Improvements in soil geochemical, ...physical, and biological properties were assessed to identify the major factors controlling microbial community development in BRs. After one year of incubation, the salinity and structure of the amended BRs had gradually improved, with pH dropping from 11.39 to 9.89, the exchangeable sodium percentage (ESP) dropping from 86.3% to 35.2%, and the mean weight diameter (MWD) rising from 0.12 mm to 0.38 mm. Further analysis of community level physiological profiles (CLPP) showed that the microbial utilization of different carbohydrates had shifted significantly, in addition to increases in the diversity index H′ (0.7–7.34), U (2.16–3.14), and the average well color development (0.059–1.08). Over the one-year outside incubation, the dominant fungal phyla in the BRs had shifted gradually from Ascomycota (85.64%) to Ascomycota (52.07%) and Basidiomycota (35.53%), while the dominant bacterial phyla had shifted from Actinobacteria (38.47%), Proteobacteria (21.39%), and Gemmatimonadetes (12.72%) to Actinobacteria (14.87%), Proteobacteria (23.53%), and Acidobacteria (14.37%). Despite these shifts, microbial diversity remained lower in the amended BRs than in the natural soil. Further redundancy analysis indicated that pH was the major factor driving shifts in the bacterial community, while aggregates were the major factor driving shifts in the fungal community. This study demonstrated that amendment with cornstalk biomass shifted the microbial community in the BRs from halophilic groups to acidogenic groups by improving the soil environmental conditions.
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•Cornstalk amendment accelerated the soil pedogenesis processes of BRs.•Physico-chemical properties of BRs were improved with pH decreased from 11.4 to 9.9.•The relative abundance of acid-producing group significantly increased as amendment.•Microbial resilience was mainly governed by pH, ESP, and MWD.
The adsorption mechanism of Cr6+ on biochar prepared from corn stalks (raw carbon) was studied by extracting the organic components (OC) and inorganic components (IC). Scanning electron microscopy, ...X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the properties of three kinds of carbon. Kinetic and thermodynamic experiments were performed. The results showed that the experimental data were fitted well by the Freundlich model and the pseudo-second-order kinetic model, and the adsorptions on the three kinds of carbon were all spontaneous, endothermic processes. The adsorption of Cr6+ by biochar was in accordance with a chemisorption process. The adsorption contribution rate of the OC was 97%, which was much higher than that of the IC. Electrostatic attraction and redox reaction were the main mechanisms of adsorption, and among them, the contribution rate of the redox reaction accounted for 61.49%. The reduced Cr3+ could both exchange ions with K+ and dissociate into solution by electrostatic repulsion; the amount of Cr3+ released into the solution was approximately 17.07 mg/g, and the amount of Cr3+ ions exchanged with K+ was 0.29 mg/g. These results further elucidate the adsorption mechanism of Cr6+ by biochar.
To solve problems in dressings for metal-bonded super-hard abrasive wheels, such as low efficiency and rapid wear, this article introduces a laser-assisted ultrasonic vibration dressing technique. ...Firstly, finite-element simulations were conducted on the dressing process of a bronze-bonded diamond wheel, and the wheel's temperature field distributions under different laser parameters were simulated. By analysing the simulation results of temperature fields and the melting point of the bronze bond, the laser parameters for laser-assisted ultrasonic vibration dressing tests were optimized, and then actual tests were carried out on the bronze-bonded diamond wheel. Results showed that, with appropriate technology parameters, the laser-assisted ultrasonic vibration dressing technique achieved desirable dressing results; specifically, the dressing force was low, the abrasive particles had high protrusions and the wheel had a large chip space and favourable surface topography.
Environmental-friendly photocatalysts and high utilization of solar energy have attracted much attention; hence, it is important to develop highly efficient and non-toxic photocatalysts. As a novel ...two-dimensional semiconductor, black phosphorus nanosheets (BPNs) have gotten extensive solicitude due to their tunable bandgap and high carrier mobility. Here, we report a new kind of environmental-friendly nanocomposite consisting of ZnAl-layered double hydroxides (LDH) and BPNs, and is obtained by electrostatic self-assembly method. The acquired photocatalysts were studied by XRD, TEM, EDX, UV–Vis diffuse reflectance spectra, mott-schottky, EIS and ESR techniques so as to gain the information on morphology, structure and properties. Compared to pristine ZnAl-LDH and BPNs, the composite photocatalyst shows the best photocatalytic activity for methylene blue (MB) degradation under visible light irradiation, and the 99% of MB was degraded in 80 min. The improvement of photocatalytic performance is mainly because BPNs provide an additional transfer channel of electrons and holes. The nanocomposites have opened up a new idea to construct black phosphorus (BP) based photocatalysts for environmental remediation.
•BP/LDH show excellent activity for MB degradation under visible light irradiation.•An environmental-friendly photocatalyst is obtained by electrostatic self-assembly.•The mechanism of BPNs enhanced photocatalytic activity is proposed.
In the last few decades, the eutrophication of lakes has been a serious issue in the middle and lower reaches of the Yangtze River watershed. To explore the relationship between lake systems and ...anthropogenic activities, sediments were collected from the Shuanglong reservoir in the Dianchi watershed in Southwest China. Total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), and the carbon isotopic ratio (
δ
13
C) were analyzed in sediment cores to reconstruct the effects of natural succession and human activities on the past lacustrine environmental conditions. A reliable chronology of the sediment core was established by using the
210
Pb dating technique, which indicated that the age span of the 70-cm sediment core is from the years 1871 to 2011. Above – 31 cm depth in the core, TN, TP, TOC, C/N, and
δ
13
C increased significantly, indicating that eutrophication has occurred since the 1980s. By combining the indicators of
δ
13
C and C/N, it was shown that terrestrial and lacustrine components were the main sources of organic matter (OM) in the reservoir, which was mostly controlled by terrestrial C
3
plants and algae. Since the 1980s, increased sewage discharge, fish aquaculture, fertilizer application, population, and economic strength have sped up the eutrophication process, and the eutrophication was further intensified in 2001.
Graphical abstract
Montmorillonite was employed as adsorbent to remove cationic and anionic dyes respectively and simultaneously. When the dye present singly, it only had a good effect to cationic dye removal. The ...experimental data well fitted to pseudo-second-order kinetic model, and the adsorption behavior followed the Langmuir model revealed that cationic dye adsorption was a monolayer coverage and charge-limited adsorption process. Molecular arrangement of the contaminants in the interlayer were analyzed by molecular simulation. As the cationic and anionic dyes co-exist, both cationic and anionic dyes could be removed. The adsorption mechanism of anionic dyes, under the circumstances, were investigated through equilibrium experiment, XRD and molecular dynamics simulation. The experimental data showed that anionic dyes in mixed wastewater were fitted Freundlich model well and the mechanism of anionic dyes removal was trapped by hydrophobic interaction on account of organic phase formed by cationic dyes in the interlayer.
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