Saturated Sodium Chloride Solution Research Articles

Beach wrack as a potential microplastic hot spot in the South-Eastern Baltic Sea environment

Beach wrack is considered as a major source of nutrients to the sandy coast ecosystems in the South-East Baltic Sea, and it serves as the natural beach sediment storage and habitat formation material. However, it also could be a hot spot for microplastic and other types of marine litter accumulation. We carried out the recovery rate experiments to determine the most reliable method for a rapid and cost-effective application to extract microplastics from the beach wrack. The aeration of media in a saturated solution of sodium chloride revealed to be statistically significant and reliable, therefore was selected as a most suitable to extract the microplastics from the beach wrack. This study shows that the concentration of microplastics is significantly different between the four analyzed compartments in the coastal zone. The microplastic concentration in a beach wrack, with a mean value of 0.47 ± 0.17 items/cm3, contained 4.7 times more microplastics than observed in the surface sand samples. This study estimated that on average over 450 million microplastic items could be found during the castaway event in the South-East Baltic Sea coast.

Eco-friendly, high-hydrophobic polybutylene succinate foam for oil-water separation

Polybutylene succinate (PBS) is an excellent biodegradable resin with good processability and toughness. The inherent hydrophobicity of this material makes it unique for the preparation of oil-water separation materials. In this paper, PBS foams with high hydrophobicity were prepared by the non-solvent induced phase separation (TINIPS) method using N, N-dimethylformamide (DMF) as a good solvent and anhydrous ethanol as a non-solvent. The effect of PBS concentration on the wettability and micro-morphology of this foam was experimentally investigated. The results showed that the foam had an optimal microporous structure with a water contact angle as high as 145° when the concentration of PBS was 30 %. It was further found that the saturated adsorption capacity of the foam was 5.55–12.39 times its mass and remained strong after 10 adsorption tests. Finally, the environmental adaptability of foams had been studied. The foams maintained their superhydrophobic and oil-absorbing properties in the presence of strong acids, strong bases, saturated sodium chloride solutions, and repeated abrasion. In addition, with the help of a pump-assisted adsorption device, oil-water mixtures can be separated continuously and quickly. This showed that the material had a broad application prospect in oil-water separation.

Bioinspired surface silicification of cellulose-mediated PVDF membranes for significantly enhancing superhydrophilicity and anti-oil adhesion toward ultrafast oil/water emulsion separation

Cellulose is a widely used hydrophilic material due to its rich hydrophilic hydroxyl groups. However, the presence of its lipophilic segment will affect the antifouling performance. Finding strategies to improve this problem has attracted considerable attention. In this work, a layer of silica was applied to a cellulose-deposited polyvinylidene fluoride membrane through a straightforward in-situ bionic silicification process of tetraethyl orthosilicate. The contact angle and oil droplet contact test proved that the high-hydrophilicity and underwater superoleophobicity of the silicified membranes were significantly enhanced. The surface structure and composition were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results of show that this improvement was mainly attributed to the presence of silicon hydroxyl groups, buried cellulose chains, and micro-nanostructures composed of cellulose and silica. The stable silica coating also provided protection for the polymeric membrane against degradation after water washing for 24 h, ultrasonic treatment (40 KHZ) for 10 min or exposure to different pH levels (pH=1, 4, 9 and 12) and saturated sodium chloride solution for 24 h. Furthermore, the silicified membrane showed outstanding oil adhesion resistance and permeation flux, enabling effective purification of different oil-in-water emulsions that were stabilized by emulsifiers. Notably, the membrane achieved a high oil removal rate (> 99.4 %) of various emulsions (toluene-in-water, cyclohexane-in-water, tetrachloroethane-in-water, soybean oil-in-water, toluene-in-salt solution, toluene-in-acid solution and toluene-in-alkaline solution emulsions). In particular, for toluene-in-water emulsions (oil droplets in the emulsion ranged from 58.77 nm to 615.1 nm), a significantly enhanced permeation flux (4777 L·m−2·h−1·bar−1) was obtained at 0.8 bar pressure. Even after multiple cycles of separation, the flux was higher than that of the unsilicified membrane. Overall, this approach is mild, simple, efficient, and easily scalable, making it an ideal method for producing superhydrophilic coatings with substantial application potential.

Parasites with zoonotic potential in dog feces and sand collected in public squares of Blumenau, Santa Catarina, Brazil

The presence of parasitized animals in streets, squares, parks, and other public places contributes to environmental contamination by infective forms of zoonotic parasites. Thus, this study aimed to evaluate the frequency of eggs, cysts, oocysts and/or larvae of parasites in samples of sand and feces present in nine public squares in the city of Blumenau, Santa Catarina, Brazil, through the four seasons of the year. Samples were collected between March 2021 and April 2022, totaling 223 dog feces samples and 106 sand samples. The dog feces samples were analyzed by the Willis method and by the Faust method, and the sand samples were analyzed by the Hoffman method and by the method of Flotation in Saturated Sodium Chloride Solution (NaCl). All analyzed squares had at least one positive sample. Of the 223 stool samples collected from March 2021 to April 2022, 31 (13.9%) were positive for at least one parasite. Of the registered positive samples, Ancylostoma spp. was the most frequent parasite, observed in 26 samples (57.8%); followed by Entamoeba sp., identified in 11 samples. As for the contamination of the sandboxes, of the 106 samples collected, 11 (10.37%) were positive for some parasite. These results highlight the importance of improving public spaces, and school educational campaigns highlighting the importance of hygiene and reducing contamination by infective parasites, thus contributing to improving public health in the city of Blumenau, SC. KEY WORDS: Zoonoses; sand contamination; hookworm; public spaces.

Development and validation of an ultrafast method of quantification of rivaroxaban in human serum using laser diode thermal desorption coupled to triple quadrupole mass spectrometry.

Rivaroxaban is an anticoagulant prescribed to patients who are at risk of medical conditions such as deep-vein thrombosis, pulmonary embolisms, and strokes caused by blood clots. The administration of this drug is monitored to adjust the dosage and evaluate patients' blood concentration. Rapid quantification of this drug in plasma could make it possible to ensure that the dose present in the blood of patients does not represent a danger for the medical intervention to be carried out. Liquid chromatography-tandem mass spectrometry is usually employed to quantify rivaroxaban in blood, plasma, and serum. Here, an alternative method of analysis based on laser diode thermal desorption-triple quadrupole mass spectrometry (LDTD-QqQMS) was developed and comprehensively validated. This new method allows the quantification of rivaroxaban in less than 13 s from sample to sample. The extraction of rivaroxaban in human serum was done by a salting-out liquid-liquid extraction with acetonitrile and a saturated sodium chloride solution. The proposed method allows the quantification of rivaroxaban in less than 13 s from sample to sample. During validation, all criteria were respected. The accuracy was <15% of the nominal value, the precision was <15%CV, and the recovery was ≥89.9%. There were no observed carryover or matrix effects. Analysis of the extracted samples established the stability of dry (24 h) and wet samples (1week) when samples cannot be analyzed immediately, a considerable advantage in a clinical setting. This method improves sample throughput by more than 1200% compared to liquid chromatography-tandem mass spectrometry methods of analysis of rivaroxaban and decreases analysis costs by reducing solvent consumption and instrument time.

Robust and stable organic sulfonate sodium salt-coated superhydrophilic mesh for ultra-fast gravity-drive oil-water separation

Due to its special wetting behavior and high selectivity, super-wetting mesh is considered as an ideal candidate material for efficient separation of water/oil mixture. However, the oil-water separation mesh suffers from the problems of poor stability and durability, leading to the failure of the separation. In this paper, a robust and stable superhydrophobic/superhydrophilic copper mesh had been successfully prepared by decorating the copper mesh via the chemical grafting of the 3-thiol-propyl trimethoxysilane (KH590) and the subsequent reaction with 2-acrylamide-2-methylpropane-1-sulfonate sodium (AMPS). It showed that the KH590 condensation compound was tightly coated on the surface and the superhydrophobic copper mesh (SUCM) possessed excellent superhydrophobicity towards various liquid droplets with a WCA of higher 150° and a sliding angle lower 5°, while the superhydrophilic copper mesh (SICM) had promising anti-oil pollution property with WCA near 0°. The SUCM and SICM also had excellent acid and alkali resistance. The obtained SICM had preeminent separation efficiency higher 99% and extremely high permeability flux of 33,441 L·m−²·h−¹ for gravity-driven toluene-water separation, and possessed excellent recyclability even after 20 cycles. Moreover, the SICM could be used to separate the oil-water mixture of aqueous solution with different pH (pH=5/7/8) and aqueous sodium chloride solution with different concentrations (5%/25%/50%/saturated aqueous sodium chloride solution). In addition, the SICM had outstanding anti-abrasion mechanical stability. This work provided a simple and effective method for the preparation of special wettability materials with excellent acid/alkali resistance and mechanical stability, and promoted the practical application of oil/water separation mesh.

Comparison of Methodologies for Microplastic Isolation through Multicriteria Analysis (AHP)

Environmental pollution caused by microplastics has evolved into a global concern; however, limited knowledge exists about microplastics in soils due to the absence of standardized extraction methods. This research aimed to develop an inexpensive, rapid method with user-friendly and environmentally sustainable outcomes for microplastics retrieval. Three salt solutions (Sodium Chloride, Magnesium Sulfate, Sodium Hexametaphosphate) and an oil solution (canola oil) underwent evaluation for microplastics extraction through the flotation process due to the density and oleophilic properties of plastics. Four widely used plastic types, obtained through fragmentation using a grinding mill from clean new plastic containers or membranes, were subjected to analysis. The experimental procedures for microplastics retrieval varied among the evaluated solutions. Through a comprehensive multicriteria analysis, the saturated Sodium Chloride solution emerged as the optimal scenario for microplastics extraction, followed closely by the canola oil scenario. The recovery method utilizing Sodium Chloride demonstrated economic feasibility, safety, and reliability. This study provides valuable insights into an effective and sustainable approach for mitigating microplastic pollution in soil, offering a promising avenue for future environmental conservation efforts.

Testing of the supramolecular complex of ivermectin Aniverm-2.0% against parasitosis on various types of livestock animals

The purpose of the research is to obtain and test a complex drug Aniverm-2.0% based on the ivermectin substance by free feeding in a mixture with concentrated feed against parasitosis of cattle, sheep, and horses.Materials and methods. Aniverm-2.0% obtained by mechanochemical technology was tested on a farm in the Shatoy Region, the Chechen Republic, on 900 sheep, 180 cattle and 156 horses in March-April 2023. To determine the infection rate, coproovoscopic examinations were conducted on 80 samples from sheep, 20 samples from young cattle and 30 samples from horses using the Fulleborn’s flotation method with a saturated sodium chloride solution. Sheep were dewormed using a group method. The drug was mixed with feed per 0.3 mg/kg for the AS or 60 mg for the drug per animal. The young cattle were kept by tie-up housing and therefore they were given Aniverm-2.0% once at a dose of 0.2 mg/kg for the AS individually in a mixture with feed. The horses were given the drug in a group method at a dose of 0.2 mg/kg for the AS or 1.5 mg/kg for the drug. Fecal samples from all animals were examined before and 2 weeks after the drug.Results and discussion. A 100% rate of infection of the sheep by gastrointestinal nematodes (Strongylata, Nematodirus spp., Trichocephalus spp.) was determined with an average number of eggs 633.3 in 1 g of feces. In 20 fecal samples from the young cattle, 16 were found to have Strongylata eggs (prevalence = 80.0%) with 222.2–280.5 specimens of Strongylata eggs found in 1 g of feces. Strongylata eggs were found in all 30 examined fecal samples from the horses, on average, 253.3 specimens/g of feces (100%). At 2 weeks after treatment, nematode eggs were found in three out of 80 examined fecal samples from the sheep, which can be explained that the sheep did not eat the appropriate dose of the drug. The drug efficacy was determined to be 99.7%. One hundred percent efficacy of the drug was obtained on young cattle and horses.

A Simple Fecal Flotation Method for Diagnosing Zoonotic Nematodes Under Field and Laboratory Conditions.

Diagnosis of canine parasites with zoonotic potential such as Toxocara canis and Ancylostoma caninum under field conditions is usually difficult due to limited access to a laboratory in rural and suburban areas in Mexico. This study aimed to detect T. canis and Ancylostoma spp. in fecal samples collected from dogs in Mexico from 2017 to 2021 under field conditions. Sample size calculation resulted in a target enrollment of 534 dogs across the country. Samples were collected directly from the rectum or the ground after defecation. Samples were stored in individual, tightly sealed, plastic bags at 4 °C. A saturated solution of sodium chloride (specific gravity [SpG] 1.20) was prepared both under field and laboratory conditions. Within 3 days of collection, 2-4 g of feces were tested for parasites using a flotation method by suspending each fecal sample in a saline solution. Feces were mixed with the flotation solution and crushed using a metal spoon. Once a uniform consistency was achieved, the fecal sample was poured into a new plastic cup using a sieve and allowed to sit for 10-15 min. Three drops from the top of the mixture were collected using a sterilized inoculating loop. The slides were placed on the microscope and parasites were identified by trained parasitologists. Fecal samples from 1,055 dogs were screened microscopically. The number of positive samples for Ancylostoma spp.was 833 (78.95% frequency) and 222 (21.04%) for T. canis. These findings illustrate the importance of identifying zoonotic helminths in dogs living in urban and rural areas in Mexico using a coproparasitoscopic technique in the laboratory and under field conditions.

Mo-based bio-derived carbon catalyst enables a tandem dehydration reaction for the direct synthesis of fuel precursors from fructose

In the pursuit of sustainable alternatives for petroleum fuels, bio-based hydrocarbons emerge as a promising choice. To explore this, a molybdenum catalyst supported on bio-derived carbon was developed, enabling the direct synthesis of fuel precursors from fructose. The catalyst was synthesized by varying the wt.% of molybdenum loading through hydrothermal treatment and carbonization. The NH3-TPD analysis revealed the presence of 1 mmol/g of acidic sites on best the catalyst. HRTEM and XPS analysis reveals that the majority of molybdenum is present as Mo6+. The synthesized catalyst effectively facilitated the dehydration of fructose to 5-hydroxymethylfurfural (5-HMF), followed by hydroxyalkylation/alkylation (DHAA) of 5-HMF with 2-methylfuran. Furthermore, compared to commercial Brønsted acid catalysts, the synthesized catalyst demonstrated remarkable performance, achieving complete fructose conversion with 36% selectivity towards the DHAA product. Moreover, an innovative approach was developed for the separation of 5,5′-((5-((5-methylfuran-2-yl)methyl)furan-2-yl)methylene)bis(2-methylfuran) and 5-HMF from dimethyl sulphoxide (DMSO) using a saturated aqueous sodium chloride (NaCl) solution in tetrahydrofuran (THF). This developed method, utilizing the bio-derived catalyst with efficient catalytic performance and effective product separation from DMSO, shows great promise for directly synthesizing fuel precursors from fructose and advancing sustainable fuel production.

Estimation of P retention capacity by the water content of soil kept with a saturated NaCl solution in a desiccator

ABSTRACT Phosphorus (P) retention capacity is an important soil parameter for site-specific nutrient management in croplands as well as a diagnostic criterion for classifying Andic properties. Air-dried soil water content is positively correlated with P retention capacity and has been proposed as a simple P retention capacity index; however, air humidity can affect the water content of air-dried soils. Therefore, in the present study, we 1) tested whether the water content of air-dried soils can be stabilized when they are kept with a saturated sodium chloride (NaCl) solution in a closed desiccator and 2) developed a model for predicting P retention capacity across various soil types. We tested 306 soil samples from paddy rice fields in Madagascar, exhibiting P retention capacities of 10.1–96.1%. Placing a saturated NaCl solution with the soil samples in a closed desiccator for one week kept the relative humidity inside the desiccator at 57–66%, regardless of the temperature and relative humidity outside the desiccator. The accuracy of the model predicting P retention capacity by soil water content was higher when soils were kept with the saturated NaCl solution [R2 = 0.870; root mean square error (RMSE) = 8.30] than without the solution (R2 = 0.812; RMSE = 9.96) at room temperature. The high correlation between P retention capacity and soil water content was mainly attributed to Al oxides. Additionally, the reproducibility of soil water content was enhanced by this method under different relative humidity conditions. However, compared with room temperature, controlling the temperature at 15°C and 30°C did not further improve the accuracy of the model when the soils were kept in the desiccator with saturated NaCl solution, although soil water content was higher at 30°C than at 15°C and room temperature. Therefore, we conclude that soil P retention capacity can be simply and accurately estimated with high reproducibility according to the water content of soils kept with saturated NaCl solution in a closed desiccator for one week at a room temperature.

Identification and characterization of extracted microplastics from agricultural soil near industrial area: FTIR and X‐ray diffraction method

AbstractMicroplastics have been found in large quantities in agricultural soil and now become a major global issue. Different types of microplastic have adverse effects on agricultural soil. The most widely used method for the extraction of microplastics in agricultural soil is the density floatation method by using saturated NaCl solution. This method includes the pre‐digestion of soil samples with H2O2 to remove all the organic matter present in the soil. Different types of microplastic particles were extracted and identified by using ATR‐FTIR viz polypropylene, polybutylene tetrapthalate, polyethylene, polystyrene, and polyethylene tetrapthalate. The crystalline nature of extracted microplastic was checked by employing XRD analytical technique. Floatation with higher density saturated sodium chloride (NaCl) solution recovered approximately 80% MPs from soil. Floatation methods were found to be effective for extracting microplastics from soils.

Poly (ionic liquid)s-silica spheres as effective core-shell catalysts for the conversion of glucose and fructose into 5-hydroxymethylfurfural

5-Hydroxymethylfurfural (5-HMF), as a significant, bio-derived platform chemical molecule, has been under extensive research due to its wide application in petrochemical industry. In this work, three kinds of poly (ionic liquid)s-silica spheres (PIL@SiO2) with various lengths of alkyl chains as effective core-shell catalysts were prepared by the polymerization and coating methods, and were used to prepare 5-HMF from glucose and fructose with optimal results. When the alkyl carbon number of PIL monomer was 18, PIL@SiO2-18 displayed good catalytic activity in 5-HMF production, resulting in the highest yields of 77.36% and 72.8% from glucose and fructose in methyl isobutyl ketone (MIBK)/ saturated solution of sodium chloride (Sat.NaCl) biphasic solvent. A possible reaction mechanism was proposed that the core-shell synergistic catalysis effectively promoted the preparation of 5-HMF from monosaccharide, in which Lewis acidic polycationic centers contributed to driving the isomerization process. The promising approach provides an efficient strategy for silica-based core-shell synergistic catalysts in the synthesis of 5-HMF from carbohydrates.

Research on visualisation of plain concrete crack depth detection based on tracer and hand-held radar

ABSTRACT Detecting the concrete crack depth has always been a technical problem. The traditional detection methods，which are based on stress wave theory, have limitations such as low accuracy, complex operation, time-consuming and laborious procedures. This paper proposes a new method based on the combination of tracer and hand-held radar to better complete this task. Its main procedures include firstly spreading tracer diffusion to the bottom of the crack propagation, and then mapping the location of the air-tracer interface by radar waves, thus visualising the crack depth information. This paper elaborates the detection principle of this new method, carried out the feasibility numerical analysis and simulation verification. Also, the concrete standard crack specimens were made, together with relevant experimental researches. As to the feasibility of the method, it is verified by using common distilled water and saturated sodium chloride solution as tracers. The detection effects of these two tracers are compared and analysed by comparing the test data with the actual depth of the specimen. This research innovatively applies tracers to actively improve the electrical ability of concrete cracks, and then uses radar to detect the electrical distribution of cracks, realising the visual detection of crack depth.

Metallographic Mechanism of Embrittlement of 15 μm Ultrafine Quaternary Silver Alloy Bonding Wire in Chloride Ions Environment.

Chloride ions contained in the sealing compound currently used in the electronic packaging industry not only interact with intermetallic compounds but also have a serious impact on silver alloy wires. A 15 μm ultrafine quaternary silver-palladium-gold-platinum alloy wire was used in this study. The wire and its bonding were immersed in a 60 °C saturated sodium chloride solution (chlorination experiment), and the strength and elongation before and after chlorination were measured. Finally, the fracture surface and cross-section characteristics were observed using a scanning electron microscope and focused ion microscope. The results revealed that chloride ions invade the wire along the grain boundary, and chlorides have been generated inside the cracks to weaken the strength and elongation of the wire. In addition, chloride ions invade the interface of the wire bonding to erode the aluminum substrate after immersing it for enough long time, causing galvanic corrosion, which in turn causes the bonding joint to separate from the aluminum substrate.

Performances of UHPC bonded cementitious composite systems containing styrene-butadiene rubber latex in a chloride-rich environment

• The green and sustainable cement-based material—UHPC was used as the repairing material to strengthen the existing cementitious substrate. • Mechanical, electrochemical and microstructural characteristics of the bonded composite systems were investigated. • The performance developments of the composite systems in a chloride-rich environment were presented. • Styrene-butadiene rubber (SBR) latex were considered to enhance the bonding properties and the electrochemical performances of the composite systems. This study investigates the mechanical, electrochemical and microstructural characteristics of UHPC bonded cementitious composite systems concerning the influences of chloride attack. The bonded composite systems with styrene-butadiene rubber (SBR) latex content of 0, 2 %, 4 %, 6 %, 8 % in UHPC layers were prepared. The experimental groups were immersed in saturated sodium chloride solution whereas the reference groups were cured in clean water. The compressive, bonding and flexural strength of the bonded systems were tested at different curing ages. The free corrosion potential, AC impedance spectroscopy and polarization resistance were considered to figure out their electrochemical behaviors. Furthermore, X-ray diffraction (XRD), pore structure characteristics as well as scanning electron microscope (SEM) observations were employed to show some light on the internal mechanism at a microscale level. Results indicate that the chloride-rich environment demonstrated certain adverse effects on the system’s mechanical properties, especially the bonding strength, which could be reduced by 20 % on average at 56d. Proper content of SBR latex was conducive to the system’s bonding strength. However, when the dosage was too large, a remarkable adverse effect on compressive strength was seen. The addition of SBR latex could further delay the corrosion of the reinforcement inside the system, from 28d of the systems without latex to 42d with 4 % SBR latex. The microstructural investigations confirmed that in a chloride-rich environment, the total pore volume was reduced by 29.4 % at 28d. A dense transition zone was observed between the substrate and the UHPC layer with a width of about 0.1 μm in clean water curing, whereas it became relatively loose and obvious bonding holes appeared in this area under severe chloride attack.

Two deaths after ingestion of a falsified pumpkin seed oil

To determine the cause of death of two people who consumed a falsified pumpkin seed oil purchased online for weight loss. Medical records for both patients provided by the hospital were critical examined. The Pumpkin seed oil ingested was seized by the police and physiochemically characterized (color and odor). Also, fatty acid was analyzed by converting total fatty acids to methyl esters using n-hexane, methanolic solution of KOH and saturated solution of sodium chloride and posterior injection on GC-MS. Analytical toxicological systematic (ATS) was performed on the oil by liquid-liquid extraction with chloroform and methanol and injected on GC-MS. Diethylene glycol (DEG) was quantified by dilution with toluene and GC-FID direct injection. Biological samples (blood and urine) were collected from both victims and screened for alcohol using GC-FID headspace analysis and also for drugs, medicines and pesticides by in house ATS GC-MS and LC-MS/MS methods. DEG and diglycolic acid (DA) analysis was only performed in the victim who died 28 days after ingestion (patient A) by protein precipitation with acetonitrile and methanol and GC-MS analysis. Both patients were first admitted presenting vomiting, headache, diarrhea, fever and asthenia. Later, were transferred for the I.C.U with worsening level of consciousness, hypotension, renal failure and progressed to coma. Patient A died 28 days after hospitalization and patient B, 60 days. The pumpkin seed oil seized was colorless and odorless and any fatty acids were detectable, inconsistent with purified pumpkin seed oil or other vegetable oils. ATS in the oil was positive for glycerin and diethylene glycol. Quantitative analysis of DEG in the product presented the value of 13% v/v. Blood analysis for patient A detected trace levels of DA on patient A, DEG was not detected. The product sold as pumpkin seed oil was a falsification, did not had any vegetable oil and was contaminated with glycerin and diethylene glycol. The symptoms presented were consisted with DEG intoxication. The elimination of DEG by the body is fast, but its metabolite, diglycolic acid (DA), may persist for a long time.

Distribution of ascariasis, trichocephaliasis and oesophagostomiasis of pigs in Central Yakutia

The article presents the results of studying the influence of the conditions of keeping pigs in industrial pig breeding using the example of Khatas Pig Complex LLC in comparison with farms of various types, on spread of diseases caused by nematode parasitism. The study of the species composition of pathogens and the spread of intestinal nematodes was carried out using helminthoovoscopic studies using the F?lleborn method. A saturated sodium chloride solution was prepared. A total of 1236 samples of pig faeces were studied. Of these, 425 samples from the Khatassky pig farm were examined by helminthoovoscopic examination. 811 samples were taken from farms in the villages of Tabaga, Sibir, Uchur, from the farm of the boarding school for the disabled in the village of Kapitonovka, and from private farmsteads in the villages of Khatassy, Vladimirovka and the Poultry Farm. According to the results of research in the industrial Khatassky pig farm, in the household farms of the village of Khatassy, the subsidiary farm of the colony of the village of Novaya Tabaga and the private sector of the village. Vladimirovka sick pigs with ascariasis, oesophagostomiasis and trichocephaliasis were not found, all pigs were healthy. The incidence of animals in private sector farms reaches 50-87 %. The average content of eggs of various helminths in 1 g of pig faeces on average in Yakutia is characterized by the following indicators: Ascaris suum - 9.78 ± 2.83, Trichocephalus suis - 11.29 ± 4.08 and Oesophagostomum dentatum - 6.3 ± 1.06 copy.

One-pot superhydrophilic surface modification of waste polyurethane foams for high-efficiency oil/water separation

Despite of the fact that polymers have brought tremendous convenience to human life, they have also inevitably caused considerable environmental pollution after their service life. Therefore, a feasible strategy that can effectively recycle waste polymers and endow them with high added value is much desired. Superwetting materials have shown great promise in oily wastewater treatment because of their high oil/water separation efficiency. However, most of these materials present some limitations, such as complex preparation procedures and poor salt tolerance, which hamper their practical applications. In this study, an iron hydroxide@polydopamine@waste polyurethane foam (Fe(OH)3@PDA@WPU) was synthesized via a facile and mild “one-pot” reaction. During this process, polymerization of dopamine and in situ growth of Fe(OH)3 were simultaneously realized, and the resultant PDA and Fe(OH)3 nanoparticles were firmly attached to the surface of WPU. Due to the abundant hydrophilic groups from PDA and Fe(OH)3 coupled with the surface roughness created by Fe(OH)3 nanoparticles, the surface properties of the foam could be changed from hydrophobic to superhydrophilic. Remarkably, the Fe(OH)3@PDA@WPU was capable of separating various oil/water mixtures even under some severe conditions (e.g. erosion in a saturated sodium chloride solution and longtime sonication), demonstrating high potential in marine oily sewage treatment. Moreover, this work also paved a new path for reducing the negative impact of waste polymer foams on our environment, and in the meantime realizing their high value utilization.

Fast screening and confirmation of 73 common prohibited compounds in cosmetics by ultra performance liquid chromatography-quadrupole-time-of-flight high resolution mass spectrometry

建立了超高效液相色谱-四极杆-飞行时间高分辨质谱(UPLC-Q-TOF HRMS)同时快速筛查确证化妆品中73种常见禁用物质的方法。样品经饱和氯化钠溶液分散均匀后,采用含0.2%甲酸的乙腈溶液超声提取,50 mg PSA净化,以8000 r/min高速冷冻离心除脂,采用Waters Acquity HSS T3色谱柱(100 mm×2.1 mm, 1.8 μm)分离。采用多反应监测高分辨扫描模式(MRM HR),以保留时间、一级母离子精确质量数、同位素丰度比和二级子离子精确质量数实现化妆品中73种禁用物质的快速筛查和确证,基质匹配外标法定量。实验比较了不同提取溶剂、净化吸附剂、色谱条件和质谱扫描模式对73种禁用物质测定的影响,并考察了膏霜剂和水剂的基质效应。结果表明,73种禁用物质线性关系良好,相关系数(R2)>0.99;检出限为5~150 μg/kg;定量限为15~450 μg/kg;膏霜剂及水剂两种基质在3个加标水平下的回收率为60.3%~130.3%,日内、日间RSD分别为0.8%~10.0%(n=6)和1.1%~15.0%(n=3)。日常风险监测中检出磺胺甲基异噁唑、甲基泼尼松、林可霉素、对乙酰氨基酚、甲氧苄啶、阿法骨化醇、倍他米松戊酸酯、溴莫尼定、氯霉素、氯苯那敏、氯倍他索丙酸酯、克罗米通、益康唑、酮康唑、泼尼松醋酸酯和泼尼松,检出含量范围为0.5~1136.1 mg/kg。该方法准确、快速、简便,可用于化妆品中73种常见禁用物质的检测。