Greater Recovery Research Articles

Highly elastic and degradable vitrimeric elastomers using polycondensation

Introducing covalently crosslinked network to polymer matrix can merge the advantages in reprocessing and durability of polymers. In this contribution, a series of high-performance vitrimeric elastomers were achieved via polycondensation. The topological structures of polymers were tuned by varying the feeding ratios of bisacetoacetate, hex‑substituted bisacetoacetate, bisamine and tris(2-aminoethyl)amine. With these structural manipulations, the vitrimeric elastomers presented great elastic recovery properties (strain recovery value up to 80%) benefiting from the introduction of long chain branch. Furthermore, the elastomers exhibited excellent reprocessing property, water vapor/oxygen barrier and adhesive properties. Specially, the elastomers could be degraded into monomer under acid conditions which enabled the elastomer synthesis again in closed loop recycling system. The ease of the polycondensation in this work to prepare highly elastic and recyclable vitrimeric elastomers demonstrated exciting opportunities for the synthesis of sustainable polymers.

Recombinant ADAMTS-13 Improves Survival of Mice Subjected to Endotoxemia.

When stimulated by proinflammatory mediators, endothelial cells release ultra-large von Willebrand factor (ULVWF) multimers that are hyperactive in activating and aggregating platelets. These ULVWF multimers can accumulate in the circulation and on the inflamed endothelium because they are insufficiently cleaved by the metalloprotease ADAMTS-13, which becomes moderately deficient under conditions of systemic inflammation. This moderate ADAMTS-13 deficiency may lead to thrombotic complications that contribute to ischemic tissue injury and organ failure that are associated with severe infections. To test this hypothesis, we investigated whether recombinant ADAMTS-13 improves the pathological course of endotoxemia in lipopolysaccharide (LPS)-treated mice. C57BL/J6 mice received a bolus infusion of either 5 µg/mouse of ADAMTS-13 or vehicle control 30 min after LPS challenge and were monitored for seven-day survival. During the monitoring period, platelet counts, VWF antigen, and ADAMTS-13 activity were measured. Thrombosis was also examined by the immunohistochemistry in the liver. We found that ADAMTS-13 reduced mortality from 66% to 34.9%. The improved survival was associated with a greater recovery from thrombocytopenia, higher plasma ADAMTS-13 activity, and less thrombotic vascular occlusion. These results suggest that systemic inflammation could result in deficient ULVWF proteolysis by ADAMTS-13 and that ADAMTS-13 improves the outcomes of endotoxemia-induced inflammation.

Electrochemical Monitoring of Sulfadiazine via La@CeO Incorporated with Reduced Graphene Oxide

In recent years, indiscriminate consumption and dumping of antibiotics have become destructive to human health and causes ecotoxicological pollution. Here, the irregular particle nanosized dendrite structure of lanthanum-doped cerium oxide (LCO) decorated with sheet-like reduced graphene oxide (RGO) composite was utilized to detect the sulfonamide-based drug sulfadiazine (SZ). LCO@RGO nanocomposite was prepared using the hydrothermal method, the synergistic effect between LCO and RGO facilitates electron transferability and conductivity which enhances the electrochemical properties toward the detection of SZ. The detection of SZ expressed a lower detection limit (0.005 µM) and linear range (0.01–265 µM) of the fabricated LCO@RGO/GCE electrode toward SZ, analyzed using the highly sensitive DPV technique. Also, DPV was utilized to determined shows good repeatability, reproducibility, and storage stability of fabricated LCO@RGO/GCE. Moreover, effective practicability was proven in human blood serum and river water samples with great recovery results. All the above probes the synthesized LCO@RGO’s thriving and outstanding electrocatalytic performance of this nanocomposite’s highly sensitive detection of SZ in real biological and environmental samples.

Influence of particle size in supercritical carbon dioxide extraction of roselle (Hibiscus sabdariffa) on bioactive compound recovery, extraction rate, diffusivity, and solubility

The purpose of this work was to establish the best particle size for recovering high yields of total phenolic compounds (TPC), total anthocyanin compounds(TAC) and total flavonoid compounds (TFC) from roselle (Hibiscus sabdariffa) by applying supercritical carbon dioxide (ScCO2). The extraction rate, diffusivity and solubility of yield in ScCO2 were also studied and calculated utilizing models. Pressure (10 and 30 MPa), temperature (40 and 60 °C), and particle size (250 µm < dp < 355 µm, 355 µm < dp < 425 µm and 425 µm < dp < 500 µm) were employed as variables in this experiment. The greatest recovery was 11.96% yield, 7.16 mg/100 g TAC, 42.93 mg/100 g TPC and 239.36 mg/100 g TFC under the conditions of 30 MPA, 40 °C and 250 µm < dp < 355 µm, respectively. The extraction rate of supercritical carbon dioxide in roselle extraction ranged from 5.19 E−03 to 1.35 E−03 mg/s fitted using the Esquivel model. The diffusivity coefficient of ScCO2 ranged from 2.17E−12 to 3.72E−11 mg/s2, as fitted by a single sphere model. The greatest solubility of global yield, TAC, TPC and TFC in ScCO2 was 1.50 g/L, 0.3 mg/L, 1.69 mg/L and 9.97 mg/L, respectively, with a particle size of 250 µm < dp < 355 µm. The smaller particle size of roselle provides the maximum bioactive compound recovery and solubility. Furthermore, the diffusivity and extraction of ScCO2 are increased by decreasing the particle size. Therefore, a smaller particle size is appropriate for roselle extraction by ScCO2 based on the experimental and modelling data.

From west to east: Heterogeneity in the life history traits of a small pelagic fish (Sardina pilchardus) throughout the Mediterranean

Small pelagic fish are key elements of marine trophic networks and are of great importance to the total landing of marine species. Over the last decades, a decrease in biomass and catches of European sardine has been described, especially in the Mediterranean Sea, as an indication of a drop in stock condition. Multiple causes, including direct and indirect anthropogenic factors, seem to affect this ecologically and economically important species. To address this issue, it is important to identify the current variability in sardine status and understand the strategies for energy allocation, which are intimately related to reproductive potential and recruitment. We analyzed the somatic condition through tissue and mesenteric lipid measurements, relative condition (Kn) and hepatosomatic (HSI) indices, and reproductive condition with the gonadosomatic index (GSI) in four subareas of the Mediterranean (Northern Alboran, Northern Spain, the Northern Adriatic, and the Aegean Sea) and an outgroup from the Atlantic. The analyses were performed within the gonadal development cycle since translocation to reproduction may mask the state of actual energy reserves for comparison. The results revealed marked differences in health status among subareas, highlighting the low condition of Northern Spain sardines throughout the annual cycle. The uniform condition throughout gonadal development in the Northern Adriatic suggests that resource availability modulates the reproductive strategy since in this locality, sardines would have high dependence on immediate reserves, not behaving as strict capital breeders. Moreover, similarities between Alboran and Atlantic stocks are discussed, highlighting the marked energy replenishment of the latter after reproduction compared to the Mediterranean stocks. The Aegean stock was the fastest to reach its maximum after spawning, presenting low condition values from the developing to actively spawning period, but with the greatest recovery at the regressing phase, coinciding with a peak in productivity. Finally, the role of the liver in sardine energy storage is analyzed considering stock heterogeneity, potentially indicating that HSI is intimately related to feeding activity. Given the divergences among stocks, we propose concrete measures for managing this resource (i.e., the need for adapting the close seasons), which could be applied to other species in similar contexts.

Важный вклад в освещение статистики национального дохода и экономической истории дореволюционной России и СССР

The author of this paper analyses the book by A. Markevich and M. Harrison, “Great War, Civil War, and Recovery: Russia’s National Income, 1913 to 1928”. He highlights the fact that the authors’ (A. Markevich and M. Harrison) calculations introduced in this article significantly expand and clarify the economic situation in Russia and the USSR in 1913-1928 from an economics point of view. For the first time, M. Harrison and A. Markevich evaluate the dynamics of national income and production of individual economic sectors, including the service industry, and compare the economies of Russia and the USSR with other countries in the same period. The calculations show a more successful development of the economy of Russia than other warring countries during the First World War. In addition, the article analyzes the decline in Russia’s share in the world economy in 1928 compared to 1913. Thereby, the authors make a reasonable conclusion about the decrease in the efficiency of the USSR economy in 1928 compared to the pre-revolutionary period. Estimates of the national income, the personal consumption fund, and the population allowed evaluating the entire economic development of pre-revolutionary Russia, the USSR, and post-Soviet Russia. Finally, the authors reveal the consequences of the economic crises of the 20th century in Russia. Drawing on personal and other researchers’ calculations, the authors criticize the opinion about the national income growth in 1928 in comparison with 1913 as exaggerated. Its significant drop during the civil war was caused by war communism as well as by the rupture of economic ties.

Review on the Beneficiation of Li, Be, Ta, Nb-Bearing Polymetallic Pegmatite Ores in China

Lithium-bearing polymetallic pegmatite ores are an important raw material for lithium extraction. They contain not only lithium but also other associated elements such as beryllium, tantalum, and niobium, with great recovery values. It is therefore often called lithium-bearing polymetallic pegmatite ore (LPPO). The recovery and utilization of Be-bearing minerals in LPPOs have yet to be further studied. This paper briefly expounds the geological aspects of LPPO deposits in China and Chinese experiences on the beneficiation of LPPOs, with special emphasis on the flotation separation of lithium-beryllium minerals. In LPPO, spodumene is the main target mineral for lithium, while beryl is the main Be-bearing mineral in a fine-grained embedded state. If the BeO grade of LPPO is greater than the industrial grade (BeO ≥ 0.04%), it will be processed for recovery. Tantalum and niobium minerals are mainly in the form of tantalite, columbite, or ferrotapiolite, which may be recovered by gravity separation or magnetic separation. Gangue minerals are mainly composed of albite and quartz. Currently, the most commonly used methods for separating the target minerals from gangue are dense medium separation and flotation. The manual sorting method has become obsolete and is expected to be replaced by machine sorting methods such as color sorters and X-ray transmission sorters. Flotation is the main method for the separation of fine-grained beryl and spodumene. The success of flotation depends on the selection of suitable pretreatment methods and appropriate flotation reagents for altering the surface properties of spodumene and beryl and for expanding the floatability differences between spodumene and beryl and between spodumene and gangue.

Characterizing Post-Fire Forest Structure Recovery in the Great Xing’an Mountain Using GEDI and Time Series Landsat Data

Understanding post-fire forest recovery is critical to the study of forest carbon dynamics. Many previous studies have used multispectral imagery to estimate post-fire recovery, yet post-fire forest structural development has rarely been evaluated in the Great Xing’an Mountain. In this study, we extracted the historical fire events from 1987 to 2019 based on a classification of Landsat imagery and assessed post-fire forest structure for these burned patches using Global Ecosystem Dynamics Investigation (GEDI)-derived metrics from 2019 to 2021. Two drivers were assessed for the influence on post-fire structure recovery, these being pre-fire canopy cover (i.e., dense forest and open forest) and burn severity levels (i.e., low, moderate, and high). We used these burnt patches to establish a 25-year chronosequence of forest structural succession by a space-for-time substitution method. Our result showed that the structural indices suggested delayed recovery following the fire, indicating a successional process from the decomposition of residual structures to the regeneration of new tree species in the post-fire forest. Across the past 25-years, the dense forest tends toward greater recovery than open forest, and the recovery rate was faster for low severity, followed by moderate severity and high severity. Specifically, in the recovery trajectory, the recovery indices were 21.7% and 17.4% for dense forest and open forest, and were 27.1%, 25.8%, and 25.4% for low, moderate, and high burn severity, respectively. Additionally, a different response to the fire was found in the canopy structure and height structure since total canopy cover (TCC) and plant area index (PAI) recovered faster than relative height (i.e., RH75 and RH95). Our results provide valuable information on forest structural restoration status, that can be used to support the formulation of post-fire forest management strategies in Great Xing’an Mountain.

Threat learning in space: how stimulus-outcome spatial compatibility modulates conditioned skin conductance response

A central question in Pavlovian conditioning concerns the critical conditions that drive the acquisition and maintenance of the stimulus-outcome association. The spatial relationship between the conditioned (CS) and unconditioned (US) stimuli is considered to exert strong effects on learning. However, how spatial information modulates Pavlovian learning remains mostly unexplored in humans. Here, we test how the compatibility between the CS and the US location influences the acquisition, extinction, and recovery (following reinstatement) of Pavlovian conditioned threat. Participants (N = 20) completed a differential threat conditioning task in which visual CSs appeared on the same (compatible) or opposite (incompatible) hemispace as the US delivery (aversive shock to one hand), while their skin conductance response served as an index of learning. Results show that initial threat expectations were biased in favor of compatible CSs before conditioning. Nevertheless, this bias was revised during acquisition to reflect current stimulus-outcome contingencies. Computational modeling suggested that this effect occurred through a higher reliance on positive aversive prediction errors for incompatible CSs, thereby facilitating learning of their association with the US. Additionally, the conditioned response to incompatible CSs was associated with initially slower extinction and a greater recovery after threat reinstatement. These findings suggest that spatial information conveyed by stimuli and outcomes can be flexibly used to enact defensive responses to the current source of danger, highlighting the adaptive nature of Pavlovian learning.

The Effect of Annealing Temperature and Quenching Media Variations On Heat Treatment Process of Cu-Zn-Al Shape Memory Alloys For Shape Memory Effect and Microstructure

Shape Memory Alloys (SMA) is a material that can return to its original shape after undergoing mechanical deformation. The most commonly SMA material used is the Ni-Ti alloy. However, it is high cost. So that it is necessary to have alternative materials, for instance Cu-Zn-Al. Several studies related to Cu-Zn-Al Shape Memory Alloys have poor mechanical properties. So there further research required in order to determine the heat treatment process of Cu-Zn-Al Shape Memory Alloys. In this study Cu-21Zn-5Al alloys were given heat treatment with annealing temperature variations (425;550;600°C) and cooling media (brine, dry ice). Annealing process affects the mechanical properties and microstructure of the test material. Cooling media results the cooling rate during solution treatment. Tests in this study include hardness test, metallographic test, XRD test, DSC test, and SME test. From the test results, it was found that all the test variables have the Shape Memory Effect. The variable that had the greatest recovery (38.3%) was annealing temperature of 450°C with the cooling solution media using brine. In addition, the most rapid cooling occurs in the brine cooling media.

A New Chromone‐based Sequential Functioning Colorimetric Chemosensor for Cu2+ and Cysteine in Near‐perfect Aqueous Media

AbstractA selective chromone‐containing colorimetric chemosensor DOCC ((E)‐N,N‐dimethyl‐2‐((4‐oxo‐4H‐chromen‐3‐yl)methylene)hydr azine‐1‐carbothioamide) was designed for the sequential probing of Cu2+ and cysteine. DOCC exhibited a marked color variation from colorless to pale yellow and had the lowest limit of detection (0.30 μM) among the chromone‐based colorimetric sensors for Cu2+ in near‐perfect aqueous media. DOCC could work to probe and quantify Cu2+ in real water samples with great recovery (98‐102%). DOCC could discriminate Cu2+ using the test kit down to 10 μM. On the other hand, Cu2+‐2⋅DOCC could selectively detect cysteine (Cys) in a sequential step through the demetallation reaction. Cu2+‐2⋅DOCC showed that its color returned from pale yellow to colorless only in the presence of Cys and its limit of detection was calculated to be 6.62 μM. The practical applications for Cys were successfully achieved in water samples with perfect recovery (99–100%) and pH tests at 7–9. FT‐IR, Job plot, ESI‐MS, and DFT calculations were applied to explain the sensing mechanisms of Cu2+ by DOCC and Cys by Cu2+‐2⋅DOCC.

An experimental assessment of carbon and nitrogen allocation in Pinus pinea populations under drought stress and rewatering treatment

Global drought effects will increase with climate change and, accordingly, plant species will be affected at different scales. Carbon (C) and nitrogen (N) are critical for plant growth and development. Drought stress disturbs the process of adjusting C and N acquisition and allocation in plants. The present study aimed to determine the N (%), C (%), C/N ratio, carbon mass (CM, g), and nitrogen mass (NM, g) in different plant organs (needle, shoot, stem, and root) in 2-years-old stone pine (Pinus pinea L.) seedlings from seven different populations of Türkiye under drought stress and rewatering treatment. The seedlings were subjected to drought until a predawn water potential between − 4.5 MPa to − 4.0 MPa. The return of the seedlings to their pre-drought level was determined by using resistance (RS), recovery (RC), and resilience (RSL) indices. The N concentration in each organ showed significant differences between the populations in response to drought while the C concentration differed between the populations only in roots. In drought, the N (%) and NM (g) values in needles increased in the populations and the increase was 50% higher in northern populations. The N (%) and NM (g) values in shoots increased almost twice in response to drought. Although C (%) and CM (g) decreased in needles and shoots in drought, they increased in stems and roots. The stem C/N ratio increased by more than 100% in some populations in drought. Root C/N ratios increased by more than 50% in drought, while they generally decreased below control values with rewatering. The C/N ratio in the stem showed great resistance and recovery, while resilience stayed negative. In conclusion, stone pine populations generally demonstrated high recovery in terms of N concentration in roots after drought. Compared to northern populations, southern populations showed more resistance to drought in terms of needle and shoot N concentration. The needle and shoot N (%) of northern populations demonstrated high resilience capacity.

Chemometrics Assisted Spectrophotometric Method Development and Validation for Simultaneous Estimation of Abacavir, Lamivudine and Dolutegravir in Dosage Form

Abstract: Aim: Multivariate methods, particularly Classical Least Square, Inverse Least Square (ILS), Partial Least Square and Principal Component Regression are invented for the quantitation of the Abacavir sulphate (ABA), Lamivudine (LAM) and Dolutegravir sodium (DOL) in their combined tablet formulation. Materials and Methods: Chemometrics is the integration of statistical and mathematical approaches to analytical data in order to extract as much information as possible. The calibration and validation sets were built using fractional factorial design. 32 ternary mixtures of calibration sets and 16 mixtures of validation set were prepared. The absorbance data matrix was created by measuring absorbance in the range of 230 to 308 nm (Δλ = 3 nm) at 27 distinct wavelengths. The models were developed with the aid of MATLAB 2018a, Minitab 16.1.1 and MS Excel 2010. Results: The recovery values were close to 100% with low standard deviation (SD) justified the high accuracy of the proposed methods. For chemometrics approaches, the RMSECV, RMSEC, and RMSEP values produced show good accuracy and precision. The values of model diagnostic tools were lowest for ILS method. Conclusion: The ILS was shown to be the most appropriate method among produced chemometric models. The chemometric method is more accurate and precise than conventional methods as the total absorbance of the ternary mixture was measured and can be utilised in simultaneous estimation. With great recoveries and precision, the proposed approach was successfully used to the assay of formulation. Keywords: Abacavir sulphate, Lamivudine, Dolutegravir sodium, Chemometrics, Spectophotometric, Validation.

Investigating the recovery in ecosystem functions and multifunctionality after 10 years of natural revegetation on fly ash technosol

Technogenic soil (technosol) developed from coal fly ash (FA) landfilling has been considered a critical environmental problem worldwide. Drought-tolerant plants often naturally grow on FA technosol. However, the impact of these natural revegetations on the recovery of multiple ecosystem functions (multifunctionality) remains largely unexplored and poorly understood. Here we assessed the response of multifunctionality, including nutrient cycling (i.e., carbon, nitrogen, and phosphorus), carbon storage, glomalin-related soil protein (GRSP), plant productivity, microbial biomass carbon (MBC), microbial processes (soil enzyme activities), and soil chemical properties (pH and electrical conductivity; EC) to FA technosol ten years' natural revegetation with different multipurpose species in Indo-Gangetic plain, and identified the key factors regulating ecosystem multifunctionality during reclamation. We evaluated four dominant revegetated species: Prosopis juliflora, Saccharum spontaneum, Ipomoea carnea, and Cynodon dactylon. We found that natural revegetation initiated the recovery of ecosystem multifunctionality on technosol, with greater recovery under higher biomass-producing species (P. juliflora and S. spontaneum) than lower biomass-producing ones (I. carnea and C. dactylon). The individual functions (11 of the total 16 variables) at higher functionality (70 % threshold) also exhibited this pattern among revegetated stands. Multivariate analyses revealed that most of the variables (except EC) significantly correlated with multifunctionality, indicating the capability of multifunctionality to consider the tradeoff between individual functions. We further performed structural equation modeling (SEM) to detect the effect of vegetation, pH, nutrients, and microbial activity (MBC and microbial processes) on ecosystem multifunctionality. Our SEM model predicted 98 % of the variation in multifunctionality and confirmed that the indirect effect of vegetation mediated by microbial activity is more important for multifunctionality than their direct effect. Collectively, our results demonstrate that FA technosol revegetation with high biomass-producing multipurpose species promotes ecosystem multifunctionality and emphasizes the significance of microbial activity in the recovery and maintenance of ecosystem attributes.

Investigation of Cardiac Arrhythmias in Non-Cardiac Surgeries with A Focus on the Type of Arrhythmia and the Type of Surgery

Background and Objective: Arrhythmias are the most dangerous cause of death in cardiac patients, the purpose of this study is to investigate cardiac arrhythmias in non-cardiac surgeries with a focus on the type of arrhythmia and the type of surgery in Imam Khomeini (RA) hospital in Ilam city in 2021. Materials and Methods: In a retrospective study, 150 patients were selected as the sample size. A questionnaire containing demographic information and type of underlying disease, type of arrhythmia and clinical outcome of arrhythmia, type of surgery and type of anesthesia. The studied data were analyzed by SPSS software. To analyze the data, T-test and chi-square were used. Results: The most arrhythmia caused in general anesthesia was related to AF arrhythmia and tachycardia, significantly 100% (P&lt;0.04). The results show that craniotomy had the highest (72.5%) clinical outcome of arrhythmia in the form of death, and there was a significant relationship between the type of surgery and the clinical outcome of arrhythmia. Conclusion: The results of this study generally showed that bradycardia is the most common arrhythmia and PVC arrhythmia is the least, general anesthesia has played an important role in causing cardiac arrhythmias, and the incidence of AF arrhythmia is evident at older ages and the greatest recovery is in the age range of 30-60 years and it was more in men than women, and more incidence of AF was reported in patients who underwent laparotomy. Postoperative AF is a frequent and serious complication in older patients

Insights into Phosphate Adsorption Performance onto Magnetic Thermal Modified Palygorskite Nanocomposites

Eutrophication caused by excessive discharging of phosphorus is a global water pollution problem. To further improve the phosphorus adsorption capacity of natural palygorskite and easy separation from liquid, magnetic thermal modified palygorskite nanocomposite (MTPG) was firstly fabricated and then characterized by XRD and SEM-EDS. The characterization results showed Fe3O4 in nano-diameters was prosperously immobilized on the surface of thermal modified palygorskite (TPG) calcinated at a temperature of 700 °C. Abundant nano-scale Fe3O4 loading almost doubled the specific surface area (SSA) of TPG. The adsorption of phosphate onto MTPG was highly pH-dependent and slightly influenced by ionic strength. According to the results from the Langmuir model, the maximum adsorptive quantity of 400.00 mg/g was counted at 298 K. The regeneration ratio was 80.98% after three regeneration cycles. The process of phosphate adsorption was confirmed to be an endothermic and spontaneous chemisorption. Thus, the cost-effective, excellent phosphate affinity, great magnetic recovery performance, and high adsorption capacity of MTPG had an enormous promising utilization on phosphate removal from aqueous solutions.

DNA‐Incorporated Biomimetic Olfactory Neuroepithelium That Facilitates Artificial Intelligence

Designing biomimetic olfactory neuroepithelium (BONe) with subnanosized active domains as artificial olfactory receptors (ORs) is highly desirable to sense various colorless and odorless hazardous odorants which find no appropriate ORs in the human olfactory neuroepithelium (ONe), yet challenging because of the unsuitability of biomolecules for a design that requires effective electronic features and stability. Herein, a DNA‐incorporated 3D BONe is introduced, where DNA facilitates optimal tuning of d‐band center, and in situ anchoring of PdO2 subnanoscale clusters (PdO2‐sNCs) on the exfoliated single‐layer reduced graphene oxide (SL rGO), to mimic wrinkled morphology of natural ONe. Unprecedentedly, BONe demonstrates benchmarked H2‐sensing performance (small recovery time of ≈30 s with a limit of detection of 50 ppb) at room temperature with yearlong durability, satisfying prerequisites of safe adoption of H2 clean energy. The great recovery is innovatively illustrated by the downshift of d‐band center of PdO2‐sNCs and strong electron transport of SL‐rGO network. An adsorption/desorption model is proposed to clarify the sensing mechanism. BONe design may eventually be integrated with artificial intelligent electronics for ppb‐level sensing of harmful gases to ensure accident prevention in modern public and military environments.

The solvent extraction is a potential choice to recover asphalt from unconventional oil ores

The abundant unconventional oil ores (about 70% of total world oil) are playing an increasingly important role in global energy supply. To obtain asphalt in unconventional oil ores, different methods, including hot water-based extraction, pyrolysis and solvent extraction, were used to recover asphalt from oil ores (i.e., Canadian, Indonesian, and Iranian oil ores). It is found that asphalt recovery obtained by solvent extraction is the highest. Multi-staged single solvent extraction was used to recover asphalt from oil ores (i.e., toluene, tetrahydrofuran: THF, xylene, petroleum: PE, ethanol), resulting in a cumulative asphalt recovery over 98% at ambient conditions by using toluene. Take Iranian oil ores with the highest oil content (83.79 wt%) as an example, great asphalt recovery was obtained by using multi-staged composite solvents extraction (i.e., toluene@xylene, toluene@THF, toluene@PE, toluene@ethanol). It is also found that introduction of toluene in the composite solvents can significantly increase the ability of single solvent’s (xylene, THF, PE and ethanol) asphalt recovery. After solvent extraction, the solvent recovery was more than 95%. This finds suggest that solvent extraction method would be potential choice to recover asphalt from unconventional oil ores, and it possesses great prospect of industrial application in the future.

Cobalt oxide functionalized ceramic membrane for 4-hydroxybenzoic acid degradation via peroxymonosulfate activation

Membrane separation and sulfate radicals-based advanced oxidation processes (SR-AOPs) can be combined as an efficient technique for the elimination of organic pollutants. The immobilization of metal oxide catalysts on ceramic membranes can enrich the membrane separation technology with catalytic oxidation avoiding recovering suspended catalysts. Herein, nanostructured Co3O4 ceramic catalytic membranes with different Co loadings were fabricated via a simple ball-milling and calcination process. Uniform distribution of Co3O4 nanoparticles in the membrane provided sufficient active sites for catalytic oxidation of 4-hydroxybenzoic acid (HBA). Mechanistic studies were conducted to determine the reactive radicals and showed that both SO4•− and •OH were present in the catalytic process while SO4•− plays the dominant role. The anti-fouling performance of the composite Co@Al2O3 membranes was also evaluated, showing that a great flux recovery was achieved with the addition of PMS for the fouling caused by humic acid (HA).

Greater than pH 8: The pH dependence of EDTA as a preservative of high molecular weight DNA in biological samples.

Ethylenediaminetetraacetic acid (EDTA) is a divalent cation chelator and chemical preservative that has been shown to be the active ingredient of the popular DNA preservative DESS. EDTA may act to reduce DNA degradation during tissue storage by sequestering divalent cations that are required by nucleases naturally occurring in animal tissues. Although EDTA is typically used between pH 7.5 and 8 in preservative preparations, the capacity of EDTA to chelate divalent cations is known to increase with increasing pH. Therefore, increasing the pH of EDTA-containing preservative solutions may improve their effectiveness as DNA preservatives. To test this hypothesis, we stored tissues from five aquatic species in 0.25 M EDTA adjusted to pH 8, 9, and 10 for 12 months at room temperature before DNA isolation. For comparison, tissues from the same specimens were also stored in 95% ethanol. DNA extractions performed on tissues preserved in EDTA pH 9 or 10 resulted in as great or greater percent recovery of high molecular weight DNA than did extractions from tissues stored at pH 8. In all cases examined, percent recovery of high molecular weight DNA from tissues preserved in EDTA pH 10 was significantly better than that observed from tissues preserved in 95% ethanol. Our results support the conclusion that EDTA contributes to DNA preservation in tissues by chelating divalent cations and suggest that preservative performance can be improved by increasing the pH of EDTA-containing DNA preservative solutions.