Carbon Ratios Research Articles

Differential impacts of pH on growth, physiology, and elemental stoichiometry across three coccolithophore species

AbstractCoccolithophores are pivotal players in ocean biogeochemistry, yet the impact of changing pH on the physiology of different species remains unclear as there has been a dominant focus on Gephyrocapsa huxleyi. Meta‐analyses of existing experimental data are challenging due to the differences in multidimensional culture conditions. This study investigated the response of three species—Gephyrocapsa huxleyi, Coccolithus braarudii, and Chrysotila carterae—under varying CO2 conditions (via pH). The sensitivity to pH differed between species, but all species showed reduced growth rates under the highest CO2 (lowest pH) treatment possibly due to high [H+]‐related inhibition. Low pH impacted cellular physiology and elemental stoichiometry, while the impact of high pH was less adverse. The changes in elemental production induced by low pH could exert a negative influence on the contribution of coccolithophores to nutrient and carbon export, especially for biogeochemically relevant open‐ocean species. pH also affected coccolith formation, especially in C. braarudii, through CO2 limitation at high pH and low calcite saturation state at low pH. Contrasting species‐specific pH sensitivities highlighted the potential for species like G. huxleyi to further outperform others like C. braarudii in an acidic ocean. Literature synthesis showed that coccolithophores show a broad CO2 optimum, although growth rates and particulate inorganic carbon to particulate organic carbon ratios consistently declined with increasing CO2. Strain‐specific CO2 optima partly contributed to the variability within responses of individual species, giving the misleading perception of a broad species‐level CO2 optimum. Strain‐specific optima exist possibly due to their adaptation to carbonate chemistry conditions at the place of origin.

A Simple Method for Triple Stable Isotope Analysis of Cellulose, Sugar, and Bulk Organic Matter-Advances and Limitations.

Determining several isotope ratios in one analysis multiplies the information that can be retrieved from a sample in a cost-efficient way. The stable isotope ratios of hydrogen (δ2H), carbon (δ13C), and oxygen (δ18O) in organic compounds are highly relevant due to their complimentary hydroclimatic and physiological signals. Different types of organic material reflect different processes and integration times, like short term in leaf sugars and long term in tree ring cellulose, but currently, no simple method exists for their triple isotope analysis. Here, we present a method that enables the isotopic analyses of the three elements H, C, and O in one run and is applicable to different types of carbohydrates and bulk organic matter. We discuss all steps required from water vapor equilibration necessary for obtaining reliable δ2H values of carbon-bound H to high-temperature conversion (HTC) of the sample to CO and H2 and to the mass-spectrometric isotope-ratio analysis. We show that reliable triple isotope analysis is possible for a large range of samples, although it results in some reduction of precision compared to individual isotope analysis. Important considerations are the equilibration procedure, the type of autosampler, selection of HTC reactor, the influence of nitrogen in the sample, the verification of δ13C values obtained by HTC versus combustion, and the selection of reference materials. By presenting a relatively simple triple-isotope method, we promote the use of multi-isotope studies in environmental sciences, which helps in addressing many important climate and ecological research challenges that we face today.

Synthesis of β-SiAlON materials from blast furnace slag by acetic acid leaching combined with carbothermal reduction and nitridation

ABSTRACT In order to optimize the utilization of blast furnace slag (BFS) and enhance the cost-effectiveness and feasibility of β-SiAlON preparation, a novel approach involving acetic acid leaching-carbothermal reduction and nitridation was proposed. The effects of acid concentration and leaching times on the leaching behavior of BFS were thoroughly investigated. The synthesis mechanism of β-SiAlON was comprehensively explored through thermodynamic analysis, X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy. The results demonstrate that selective leaching of Ca and Mg elements from BFS can be achieved while effectively enriching Si and Al elements in the filter residue. Under optimized leaching conditions, the contents of CaO and MgO in the residue are reduced to below 3% and 1%, respectively. The mass ratio of alumina to silica (w(Al)/w(Si) = 0.3-0.4), the molar ratio of carbon to oxygen (n(C)/n(O) = 0.5), the roasting temperature at 1673 K and the roasting time for 4 hours should be precisely controlled in order to successfully synthesize β-SiAlON from BFS. In summary, the primary reaction pathways for β-SiAlON synthesis from BFS can be described as follows: C4H7AlO5/AlO(OH) transforms into Al2O3, which further reacts with SiO2 to form β-SiAlON; alternatively, Al2O3 reacts with SiO2 to produce mullite, which subsequently converts into β-SiAlON.

Optimization of preparation process for seasoning derived from the lees of Shaoxing Huangjiu(Chinese yellow rice wine) based on multi round progressive strategy

Huangjiu lees are rich in flavor compounds, but traditional methods of utilizing them remain inefficient. Developing an efficient process for the rapid release and extraction of these flavor compounds from Huangjiu lees to produce lees-flavored seasonings holds significant promise. To tackle this complex process, a multi-round, progressive optimization strategy was devised. First, four separate orthogonal experiments identified the key factors for pre-fermentation, acid hydrolysis, enzyme hydrolysis, and debittering/decolorization, which were determined to be pre-fermentation time, HCl concentration, flavor enzyme concentration, and activated carbon ratio, respectively. Subsequently, response surface methodology was employed to rank the importance of these four factors in influencing the sensory score of the seasonings. The optimal conditions were determined as follows: pre-fermentation time of 7.785 days, HCl concentration of 14.978 %, flavor enzyme concentration of 6.276 %, activated carbon ratio of 7.496 %, with an expected sensory score of 45.117. Finally, the AI-based ANN-PSO method was applied for further refinement, yielding optimized conditions of a pre-fermentation time of 7.417 days, HCl concentration of 12.569 %, flavor enzyme concentration of 6.843 %, activated carbon ratio of 6.946 %, and an improved expected sensory score of 47.838. Verification experiments confirmed the superiority of the latter conditions. This study not only establishes a novel method for the efficient utilization of the abundant flavor resources in Huangjiu lees, which has substantial market potential, but also demonstrates that combining multiple optimization methods in a stepwise, multi-round approach is effective in addressing complex manufacturing processes involving multiple stages and factors.

Biofabrication of polyhydroxybutyrate (PHB) in engineered Cupriavidus necator H16 from waste molasses

BackgroundCupriavidus necator H16, a native polyhydroxybutyrate (PHB) producer, has emerged as a promising candidate for sustainable bioproduction to replace conventional plastics. However, most fermentation processes still rely on expensive substrates. Therefore, developing an eco-friendly bioprocess for PHB using waste materials is urgent and essential. MethodAn engineered strain Lgg-H16, incorporating galactose permease (galP) and glucokinase (glk), was employed to boost glucose uptake and phosphorylation. Then, biomass and PHB production were improved by fine-tuning the carbon, nitrogen, and phosphorus ratios. Yeast extract was supplemented as an additional nutrient, and a tailored feeding strategy was applied to maximize PHB output. To lower the manufacturing costs, waste molasses from the sugar industry, was utilized for fed-batch fermentation. The physical properties of the PHB, such as molecular weight and crystallinity, were analyzed using differential scanning calorimeter (DSC) and gel permeation chromatography (GPC), respectively. Significant resultsEngineered Lgg-H16 strain exhibited a 2.15-fold increase in specific growth rate compared to the wild type with a C:N:P ratio of 20:1:18, as well as supplemented 2 g/L yeast extract in the medium. PHB yield reached 17.4 g/L with 70 % content from waste molasses in fed-batch fermentation with an atomizer to increase gas dispersion, costing only 1 % of pharmaceutical-grade glucose. All physical properties of the PHB produced by Lgg-H16 were comparable to commercial product, supporting this promising bioprocess by using the low-cost feedstocks for high-value bioplastic PHB.

Humic fractions as support for the classification of high-mountain Organossolos in the southeast of Brazil

ABSTRACT Brazilian Soil Classification System (SiBCS) adopts a hierarchical approach to classify soils using specific diagnostic attributes. Organossolos (Histosols) class is differentiated according to its genesis, especially because the parent material is organic, thus requiring diagnostic attributes that describe the unique properties of soil organic matter (SOM). This study aimed to propose the use of labile organic carbon and the C and N contents of humic fractions and their ratios for the family and series levels of the Brazilian Soil Classification System for Organossolos in high mountainous regions. Quantitative chemical fractionation of SOM was performed to obtain the humic fractions and determine the labile oxidizable carbon in 16 Organossolos profiles from Itatiaia National Park, RJ. Carbon and nitrogen contents of the humic acid, fulvic acid, and humin fractions were obtained, as well as the percentages of these fractions in relation to the total carbon and nitrogen in the soil. Carbon and nitrogen ratios were calculated for each fraction. Results showed little variation in the levels of labile organic carbon between the profiles but a large variation in total carbon and nitrogen levels, especially in the Organossolo Fólico Hêmico lítico profile. The ratios between the carbon and nitrogen of humic acids and fulvic acids (means of HAC/FAC = 1.61 and AHN/FACN = 1.05), carbon and nitrogen of the alkaline extract and humin (means of AEC/HUMC = 0.71 and AEN/HUMN = 0.38), carbon and nitrogen of the alkaline extract, and total carbon and total nitrogen (means of AEC/TC = 0.28 and AEN/TN = 0.19) were effective in determining the humification level of the profiles. This study proposes that the attributes evaluated, especially the ratio between the carbon of the alkaline extract of the humic substances (carbon of the fulvic acid fraction + carbon of the humic acid fraction) and the total soil carbon, as well as the ratio between the C and N of the humin fraction, should be used to define lower categorical levels of Organossolos. This new approach could facilitate the classification of these soils and contribute to a better understanding of the composition of Organossolos in Brazil.

Grassland degradation-induced soil organic carbon loss associated with micro-food web simplification

Soil micro-food webs play a vital role in sustaining soil carbon cycling and stocks through the activities and interactions of individual organisms. However, grassland degradation disrupts these micro-food webs and is expected to reduce soil carbon stocks. This hypothesis was tested along degradation transects that were established in alpine meadows and steppes in arid regions, examining how multitrophic organisms and microbial metabolic efficiency respond to grassland degradation and how these responses relate to soil organic carbon (SOC). Grassland degradation reduced microbial necromass accumulation coefficient (the ratio of microbial necromass carbon to microbial biomass carbon) and increased microbial metabolic quotient (the ratio of soil respiration rate to microbial biomass carbon), indicating that microbes may prioritize SOC decomposition for resource acquisition over growth and necromass accumulation. Degradation led to increased bacterial and fungal diversity, reduced protist and nematode diversity, and simplified the structure of micro-food web (network complexity). Overall, grassland degradation reduced microbial metabolic efficiency, linked to reduced plant biomass, lower soil clay content, and a simplified micro-food web—particularly weakening interactions among microbes, microbivores, and predators—which is associated with SOC loss in degraded grasslands. These findings indicate the necessity of maintaining micro-food web structures to promote soil carbon sequestration in degraded grasslands.

Preparation of lignin oil with high H content by electrolyzing alkali lignin pretreated by organic thiol/hydrogen peroxide /ethylene glycol

Pretreatment can improve the reaction selectivity of lignin, promote the subsequent electrolytic catalysis of lignin depolymerization and conversion into high-quality lignin oil, thereby enhancing the energy conversion efficiency of lignin. The degree of depolymerization and electrochemical reduction of lignin under different pretreatment methods was investigated in this study, it was found that ethylene glycol /hydrogen peroxide/β-mercaptoethanol can break β-O-4 bond in a mild condition to increase the depolymerization performance of lignin, and reduced its number-average molecular weight significantly. The effects of electrode material, reaction temperature and current density on the yield of lignin oil and volatile component content were discussed. The highest the yield of lignin conversion could reach 95.0 %, and small molecular products dominated by alkanes and aromatics were obtained, of which the monomer yield was 25.1 wt%, which could reduce the oxygen carbon ratio of lignin effectively, improve the calorific value of lignin oil (34.39 MJ/kg). This study will provide technical reference for the greenly and efficiently conversion of lignin into hydrocarbon fuels under milder conditions.

Effectiveness of ozone nanobubble treatments on high biomass cyanobacterial blooms: A mesocosm experiment and field trial

Cyanobacterial harmful algae blooms (cyanoHABs) are a global threat to water resources, and lake managers need effective strategies to suppress or control them. Algaecides may have negative environmental impacts, and their use is becoming restricted. Nanobubble ozone technology (NBOT) is an emerging water treatment option with potentially fewer negative impacts. We assessed the effectiveness of NBOT in treating Planktothrix cyanoHAB from Grand Lake St Marys (GLSM, Ohio USA) in a mesocosm (2,000L) experiment and two 4-week trials in a GLSM embayment (Sunset Beach, SBE; ∼4.7∗107 L). In mesocosms, the medium (1.21 ± 0.08 ozone to dissolved organic carbon ratio, O3:DOC) and high (2.04 ± 0.07 O3:DOC) doses decreased both chlorophyll a (chl-a) and phycocyanin by 98–99% and microcystins by 62% and 92%, respectively. The low dose (0.68 ± 0.05 O3:DOC) decreased chl-a and phycocyanin by over 70%. No effect was observed for chl-a nor microcystins in both oxygen-only nanobubble mesocosm treatments and the SBE NBOT trial. The average O3:DOC at SBE was less than the low NBOT mesocosm experiment dose, and the percentage of water treated was lower. DOC chemistry, as indicated by SUVA254, was more oxidized at the NBOT outlet than the inlet in the SBE trial, suggesting interaction with ozone. However, no differences were observed 3m from the outlet, indicating minimal treatment reach. The mesocosm experiment highlighted NBOT's ability to control cyanoHABs, but the limited effectiveness of NBOT at SBE was likely due to high cyanobacteria biomass and DOC at the onset of treatment, low O3:DOC, and low percentage of lake water instantaneously treated.

Changes in soil inorganic carbon following vegetation restoration in the cropland on the Loess Plateau in China: A meta-analysis

Vegetation restoration in the cropland has been widely implemented to protect the ecological environment of the Loess Plateau, China. However, a quantitative and comprehensive understanding of the changes in soil inorganic carbon (SIC) after vegetation restoration is lacking. Based on 637 pieces of data from 35 studies on the Loess Plateau, we performed a meta-analysis to quantify the variations in SIC after vegetation restoration in the cropland and analyze the influences of environment factors on the variations in SIC. Overall, SIC significantly increased by 6.73% after vegetation restoration. The conversions of cropland to broadleaf forestland, coniferous forestland and grassland significantly increased the SIC contents by 3.16, 14.77 and 6.32%, respectively. The response ratio of SIC (RR-SIC) to vegetation restoration was positively related with restoration age, the response ratio of soil organic carbon and the soil pH respectively, but was significantly negatively correlated with mean annual precipitation and mean annual temperature. The results demonstrated that vegetation restoration in cropland has a high potential to SIC sequestration on the Loess Plateau. The relationship of RR-SIC with environmental factors indicated that the production of pedogenic inorganic carbon plays a crucial role in SIC sequestration after vegetation restoration in the cropland on the Loess Plateau. Our findings highlight that SIC is as vital to soil carbon sequestration as soil organic carbon after vegetation restoration, and SIC should not be neglected for assessing carbon sequestration capacity of vegetation restoration on the Loess Plateau.

Rosuvastatin/calcium carbonate co-precipitated nanoparticles: A novel synergistic approach enhancing local bone regeneration in osteoporotic rat model

This study aimed at preparing sustained release rosuvastatin (Ru) calcium carbonate (CC) co-precipitate nano-formulation for local intra-osseous application in osteoporotic rats. Nano-formulations were prepared by the co-precipitation method using different concentrations of polyvinyl alcohol (PVA) (0.2, 0.4, 0.6 %) as a stabilizer and equimolar ratios of calcium chloride and calcium carbonate (0.1, 0.3 or 0.5 M). Pre-formulation examination including; FTIR and X-ray diffraction confirmed the formation of CC nanoparticles in a crystalline structure that was preserved before and after loading with Ru. The optimized formula showing; PS of 105.71 ± 5.10 nm, PDI of 0.25 ± 0.02, ZP of −44.70 ± 0.09 mV, % EE of 60.16 ± 1.58 and a quasi-spherical nanoparticle with nano-deposition of Ru crystals adsorbed on them as seen under TEM and SEM, was then integrated in 20 % Pluronic gel. The Ru-gel exhibited good rheological behavior with a short gelation time of 20 sec and a sustained release pattern of 30 % for the optimized Ru/CC gel versus ≈ 90 % for the Ru/CC dispersion after 6 h. In-vivo, ovariectomy-induced osteoporotic rats were used to cause a bone defect in the tibial metaphysis. The drill-hole defects were then filled with the formulations under test and examined 30 days postoperatively. Through SEM-EDX scanning, histological assessments, and evaluation of bone metabolic markers, Ru/CC treatment significantly enhanced bone healing, improved bone microarchitecture, increased trabecular bone area, enhanced osteogenic gene expression, and reduced osteoclast activity. Experiments proved that Ru/CC successfully enhances osteogenesis and reduces osteoclastogenesis, proposing it as a promising therapeutic approach for enhancing bone regeneration in osteoporosis.

Characterization of native starch granules from different botanical sources and the contribution of surface-associated lipids and proteins to the accuracy of 3D food printing

3D printing of starch-based materials has become of great interest during the last few years. However, the characterization of the printing inks and the prediction of the printing accuracy is still challenging. Therefore, the surface chemistry and particle size distribution of starches from different organic sources (wheat, potato, rice) were characterized, and their influence on printing accuracy was investigated. Starch granules surface is covered with different lipids (e.g. phospholipids) and protein (e.g. puroinduline), which are known to influence the properties of starch and the interaction with other ingredients. These surface-associated lipids (SSAL) and proteins (SSAP) were removed individually from starch granules' surfaces to investigate the influence of particle-particle interplay on the printing behavior. Therefore, the amount of surface proteins was calculated by XPS analysis based on the nitrogen to carbon (N/C) ratio of each starch granules' surface. There was a linear correlation (r = −0.84) between the N/C ratio and the printing accuracy, measured by a geometrical deviation, indicating a dominating influence of the surface composition of the individual starch granules. The deviation from the geometrical template was higher for printed samples with smaller N/C ratio and therefore less protein on the starch granules’ surface. No influence of the particle size was found, as the samples from different starches containing the same amount of SSAPs had the same printing accuracy. These results reveal that the particle-particle and particle-polymer interactions mainly influence by the protein content on the starch granule surface seem to be decisive for the geometrical stability of 3D food printing. It is therefore recommended to use starches with a high amount of SSAPs for 3D printing applications.

The journey of loggerhead turtles from the Northwest Atlantic to the Mediterranean Sea as recorded by the stable isotope ratios of O, C and N of their bones

Loggerhead turtles, Caretta caretta, born on the nesting beaches of the Northwest Atlantic Ocean (US eastern coast) undertake a transoceanic migration immediately after birth, traveling eastward in association with the Gulf Stream and reaching the coasts of Europe and northwestern Africa when two or three years old and 20–30 cm in curve carapace length. Once there, they may remain in the eastern Atlantic or enter the Mediterranean Sea before eventually returning to the western Atlantic several years later. However, the timing of entry into the Mediterranean and the length of the period spent inside are poorly known. To study this, skeletochronology was combined with the analysis of the stable isotope ratios of oxygen (δ18O), carbon (δ13C) and nitrogen (δ15N) in the cortical bone of the humerus of 31 juvenile loggerhead turtles of Northwest Atlantic origin found dead stranded in the Balearic Islands. Incremental bone layers were sampled to assess changes in habitat through the movement across isotopically distinct water masses and the existence of any ontogenetic change in the diet. Although the incremental layers corresponding to the very first years of live were missing in all individuals, the wide range of δ18O values of the remaining layers suggested that these juveniles moved between water masses differing in salinity, from the eastern Atlantic, the western Mediterranean, and the much saltier eastern Mediterranean, without any consistent temporal pattern. Nevertheless, upon reaching ten years old, loggerhead turtles seem to settle in low salinity areas of the western Mediterranean, such as the Algerian Basin or the Alboran Sea, likely preparing for their return towards their natal beaches in the Northwest Atlantic. Finally, the changes observed in the δ13C and δ15N values were small, suggesting only minor ontogenetic changes in their diet throughout the analysed life stages.

Evidences of the sources of suspended sediments and ecological processes in the Yellow River Basin.

Terrestrial originated suspended sediments from the Yellow River are crucial to understand the sources of the suspended sediment and ecological processes in estuary. This study integrated physicochemical indices, stable isotopes and microbial communities to trace the origin of the suspended sediment, and investigated the importance of ecological processes in community assembly via the null model and neutral community model. Global data revealed that the dissolved and particle ratios of carbon and nitrogen obviously decreased from the headstream to the estuary. A significant positive correlation was detected between δ15N and δ13C from Henan Province to offshore. Notable differences in bacterial community composition were found between Henan Province and offshore in dry season, whereas nearly no remarkable changes were detected throughout the entire YR basin in wet season. Multiple lines of evidence from physicochemical analysis, stable isotopic and genetic tracing revealed the possibility that the terrestrially- derived suspended sediments in the lower reaches contributed the most carbon and nitrogen to the suspended sediment in the estuary. Dispersal limitations for stochastic processes had the greatest relative importance in the community assembly of the two seasons. A greater degree of homogeneous selection for deterministic processes was exhibited in dry but not wet season. Proteobacteria had a remarkable correlation with salinity and conductivity in both dry and wet seasons, while Elusimicrobiota was more strongly related to NO3-N in dry than that in wet season. Therefore, this study elucidates the source of suspended sediment in estuaries and highlights the ecological processes involved in altering the microbial community composition in Yellow River basin.

Investigation into Recycling of Iron Oxide Scale on H13 Steel by Low‐Temperature Carbothermal Reduction Method

The current method for recovering iron oxide scale in the steel industry is not economically optimal, especially for high‐alloy scales found in alloyed steel. This study focuses on iron oxide scale containing valuable metals like chromium (Cr), molybdenum (Mo), and vanadium (V). The required carbon addition is calculated based on the iron and chromium oxides in the scale. The effects of varying carbon additions and reduction temperatures on reduction efficiency are thoroughly examined. Kinetic studies show that as temperature and carbon increase, the rate‐limiting step shifts from interfacial diffusion to interfacial reaction. Reduction experiments assess carbon utilization, metallization rate, deoxidation rate, and removal of harmful elements. Results show that high temperatures hinder sulfur (S) and phosphorus (P) removal, and excess carbon reduces carbon utilization efficiency. Optimal conditions are a carbon ratio of 0.2174 and a temperature of 1150 °C. The carbothermic reduction product requires further refinement through conventional ladle slag systems to meet the quality standards for metallic materials. Over 65% of alloying elements are recovered, though phosphorus content remains slightly higher than in finished alloy steel. The materials from this study are suitable as high‐quality intermediates for alloy steel production.

Workability of Nanomodified Self-Compacting Geopolymer Concrete Based on Response Surface Method

Geopolymer concrete is more low-carbon and environmentally friendly than Portland cement concrete. Nanoparticle modification can help to improve the mechanical and durability performance of concrete, but due to its large specific surface area and high activity, it may deteriorate its workability. However, there is currently limited research on the effect of nanomodification on the workability of freshly mixed self-compacting geopolymer concrete (SCGC). This article conducted SCGC workability experiments using the response surface methodology, which included 29 different mixtures. The effects of nano-silica (NS), nano-calcium carbonate (NC), alkali content (N/B), and water cement ratio (W/B) on the workability of SCGC were studied. The experimental results show that the addition of NS and NC can reduce the slump expansion of SCGC, and the combination of the two significantly increases the amplitude of slump expansion with the change in nanomaterial content. An increase in N/B will reduce the expansion time and clearance value of SCGC. As N/B increases from 4% to 4.4%, the slump extension of SCGC decreases, and with a further increase in N/B, the slump extension increases significantly to 68.1 cm, which means that the slump extension of SCGC increases by 9.5% as N/B increases from 4.4 to 5. This study can provide a reference for optimizing the fresh performance of geopolymer concrete and improving the mechanism of nanomaterial-modified geopolymer concrete.

Multi response optimization of synthesis of boron compounds by Dopting to graphene oxide in the Modified Hummers method

The synthesis of graphene oxide can be improved by replacing boron compounds for NaNO3 and H3PO4 in the Hummers technique, using the TOPSIS-Based Taguchi method, which was employed to analyze multiple responses. L9(34) experimental design with four parameters and three levels was used to describe how boron compounds are used in the Hummers technique of synthesizing graphene oxide. The parameters chosen for each 2 g graphite amount, include the specific boron compound, the quantity of boron compound, the quantity of sulfuric acid, and the quantity of potassium permanganate. Seven quality criteria have been established to conduct parameter effect analysis. Raman analysis was conducted to determine the ratio of D peak intensity to G peak intensity (ID/IG) and 2D peak intensity to G peak intensity (I2D/IG), SEM + EDS was used to measure the atomic ratio of carbon to oxygen (C/O), BET analysis was employed to measure the surface area (SA), XRD analysis was performed to measure crystallite (Cs), ZETA-SİZER analyses were performed to measure Zeta Potenital (ZP) and Particle Size (PS) analyses and FTIR analysis was used for structure characterization. A reference experiment was conducted using H3PO4 in the Hummers method, and the recovery rates were documented. L9(34) The results of the best quality criteria in the design of the experiment, and improvement rates were calculated based on the reference experiment. The improvement rates calculated according to the quality criteria are for ID/IG, I2D/IG, C/O, SA,Cs,ZP and PS respectively 5 %, 190 %, 178 %, 74 %, 77 %, 66 %, and 30 % has been achieved.

Novel method for quantifying the ratios of sp3/sp2 hybridized carbon in diamond-like carbon films using soft X-ray emission spectroscopy

This study presents a pioneering method for quantifying the ratios of sp3/sp2 hybridized carbon in diamond-like carbon (DLC) films. The novelty lies in using soft X-ray emission spectroscopy (SXES), a technique not widely employed in this context. The DLC films, obtained through various deposition methods, were characterized for hydrogen content, film density, and sp3/sp2 ratio using Rutherford backscattering spectroscopy/Elastic recoil detection analysis (RBS/ERDA), X-ray reflectivity (XRR), and SXES, respectively. To ensure the reliability of the SXES method, it was validated through comparative analysis with near-edge X-ray absorption fine Structure (NEXAFS) spectroscopy, providing confidence in its accuracy. While NEXAFS provided consistent sp3/sp2 ratio measurements in hydrogen-free DLC films, its accuracy in hydrogenated DLC films was impacted due to poor accuracy when applied to this film group. In contrast, SXES demonstrated greater precision in hydrogenated and hydrogen-free DLC films, revealing sp3/sp2 ratios ranging from 36 % to 62 %, corresponding variations in hydrogen contents and film densities. These findings highlight the superior utilization of SXES in accurately determining the sp3- and sp2-hybridized carbon ratios, particularly in hydrogenated DLC films, offering a robust alternative to NEXAFS and paving the way for enhanced characterization and application in various industrial fields.

The impact of atmospheric ultrafine particulate matter on IgE-mediated type 1 hypersensitivity reaction

The effect of atmospheric ultrafine particulate matter (UPM) on respiratory allergic diseases has been investigated for decades; however, the precise molecular mechanisms underlying these effects remain poorly understood. In this study, we used a simulated UPM (sUPM) generated via the spark discharge method to refine black carbon, a core particle that closely mimics real-world UPM, including the size (i.e., size of agglomerates: 165nm) and organic carbon/elemental carbon ratio (i.e., 2.62). When 25μg/mouse of dispersed sUPM was instilled into the lungs of mice, it promoted the infiltration and degranulation response of pulmonary mast cells, and exposure to sUPM in an immunoglobulin E (IgE)-mediated passive anaphylaxis model intensified the degranulation response of peripheral mast cells. These effects of sUPM were demonstrated to amplify the downstream signaling mechanism of the high-affinity IgE receptor (FcεRI) mediated by IgE when tested using rat basophil leukemia (RBL)-2H3 and mouse bone marrow-derived mast cells (BMMCs) collected from the bone marrow of BALB/c mice. These results indicate that airborne UPM can exacerbate type 1 hypersensitivity reactions by enhancing the IgE-mediated signaling pathways within mast cells. Furthermore, this study provided mechanistic evidence on exacerbated allergic pulmonary diseases induced by UPM inhalation.

Chemical composition, multiple sources, and health risks of PM2.5: A case study in Linyi, China's plate and logistics capital

Elucidating the chemical composition, sources, and health risks of fine particulate matter (PM2.5) is crucial for effectively preventing and controlling air pollution. This study collected PM2.5 samples in Linyi from November 10, 2021, to October 15, 2022, spanning the period of the 2022 Winter Olympics and Paralympics. The analysis focused on seasonal variations in the chemical composition of PM2.5, including water-soluble ions, inorganic elements, and carbonaceous aerosols. Results from the random forest model indicated that control measures during the Olympics and Paralympics reduced PM2.5 concentrations by 21.5% in Linyi. Organic matter was the dominant component of PM2.5, followed by NO3−, SO42−, and NH4+. Among secondary inorganic ions, SO42− exhibited the highest concentration in summer, while NO3− and NH4+ showed the lowest concentrations. The inorganic elements S, K, Fe, and Si had high mean annual concentrations, underscoring the need for targeted control measures for plate production, bulk coal burning, and biomass combustion in Linyi. The organic carbon (OC) to elemental carbon ratio (17.7–20.5) in Linyi was high, highlighting the importance of addressing secondary OC pollution. According to the positive matrix factorization model, coal burning, and the secondary formation processes of sulfate and nitrate were the dominant sources of PM2.5. Backward air mass trajectories revealed substantial contributions from the southeastern, local, and southwestern regions of Linyi. This suggests the need for enhanced regional joint prevention and control efforts between Linyi and neighboring cities, such as Rizhao and Jining in Shandong Province, as well as northern cities in Jiangsu Province. The highest non-carcinogenic and carcinogenic risks (CRs) were associated with As. coal burning posed significant noncarcinogenic risks and a moderate CR, contributing 41.7% and 44.0% of the total health risk, respectively. These findings are crucial for developing effective air pollution prevention and control strategies.