Preparation Method Research Articles

A review of high-entropy ceramics preparation methods, properties in different application fields and their regulation methods

High-entropy alloys (HEAs) provides a new way to develop new materials with adjustable performance due to their unique cocktail effect. Inspired by HEAs, a ceramic material with high-entropy effect has been developed, which was named high-entropy ceramics (HECs). With the introduction of the concept of entropy stability, research on HECs has developed rapidly. At present, research on the performance of HECs has extended to traditional performance such as thermomechanical performance, oxidation resistance, and magnetic properties, as well as emerging performance such as catalytic performance, optical properties, and radiation resistance. Based on the definition of HECs, this paper reviews the crystal structure and preparation methods of HECs and supplements the simulation calculation methods and descriptors which is suitable for HECs. In this paper, the performance of HECs at this stage is divided into traditional fields and emerging fields according to the application fields. A variety of performance regulation methods are reviewed, and the development and research directions of HECs are prospected.

Promotion of Different Active Phases in MnOX-CeO2 Catalysts for Simultaneous NO Reduction and o-DCB Oxidation

AbstractMnOX-CeO2 catalysts with different Mn and Ce content were prepared to evaluate the effect of metal content on catalytic properties and activity in the simultaneous NO reduction and o-DCB oxidation, in order to elucidate the most active species for the process. Catalytic properties were evaluated by ICP-AES, XRD, skeletal FTIR, STEM-HAADF, XPS, N2-physisorption, H2-TPR, NH3-TPD and pyridine-FTIR. Catalysts with 85%Mn and 15%Ce molar content have been found to be the most active. Their excellent catalytic performance is related to the coexistence of Mn in different phases, i.e., Mn species strongly interacting with Ce and segregated Mn species. The effect of the preparation methods has also been deeply investigated: Co-precipitation method (CP) leads to Mn segregation as Mn2O3, whereas sol-gel preparation method (SG) promotes the formation of an amorphous powder. The synergy between segregated Mn2O3 species and Mn species in high interaction with Ce (resulting in a mixed oxide phase) leads to the presence of Mn with different oxidation states. This effect, together with the high oxygen mobility caused by structural defects, enhances redox, acidic and oxidative properties. The improvement of catalytic properties with Mn content also favors NO reduction side-reactions, with N2O and NO2 being the most important by-products, whereas it limits the production of chlorinated organic by-products in o-DCB oxidation.

Efficient degradation of phenol wastewater using CuFe2O4 as highly active catalyst in the microwave-assisted catalytic wet peroxide oxidation process

Six kinds of CuFe2O4, including capsule-shaped CuFe2O4-C, plate-shaped CuFe2O4-P, polyhedral-shaped CuFe2O4-O, and irregular shaped catalysts prepared by co-precipitation (CuFe2O4-CO), by microwave heating (CuFe2O4-MW), and by hydrothermal synthesis (CuFe2O4-S), were used in the microwave-assisted catalytic wet peroxide oxidation (MW-CWPO) process to remove phenol from wastewater. The physicochemical properties of the catalysts were dependent on preparation methods. The catalytic activities were in the order of CuFe2O4-CO (95.3 %) >> CuFe2O4-P (78.8 %) > CuFe2O4-C (72.7 %) > CuFe2O4-MW (67.1 %) > CuFe2O4-S (63.3 %) > CuFe2O4-O (60.0 %). Effects of CuFe2O4-CO dosage, H2O2, pH, phenol initial concentration, anions, and MW in the MW-CWPO process were then systematically studied. Under optimal conditions of pH = 3, H2O2 = 1 mL/L, and CuFe2O4-CO = 0.5 g/L, MW energy of 99 kJ (550 W, 3 min) and 132 kJ (550 W, 4 min) were found essential to achieve 99.6 % removal rate of phenol and 95.3 % removal rate of chemical oxygen demand (COD). Possible degradation pathways were suggested: phenol was firstly oxidized into hydroquinone and catechol, which further degraded into p-benzoquinone, 1,2-benzoquinone, respectively. Finally, these compounds transformed into oxalic acid, CO2, and H2O within 4 min. The proposed mechanism suggested that the catalyst CuFe2O4-CO generates more “hot spots” due to its irregular shape, which enhances MW scattering and absorbing abilities. Consequently, the chemical composition and crystal structure of the catalyst significantly promote the decomposition of H2O2 to generate free radicals. The CuFe2O4-CO has an opportunity of potential engineering application due to its high efficiency and stability.

Ensemble learning evaluation of mechanical property for mining waste cemented backfill

Processing the large amount of waste rock generated from mining into backfill materials enables the resource utilization of waste materials. Additionally, the mechanical properties of backfill materials influence the stability of overlying strata. Therefore, this study established a large-scale dataset of coal gangue-based and tailing-based backfill materials. Three novel ensemble learning models were developed to evaluate the nonlinear effects of 29 dimensional factors on the mechanical properties of backfill material. Additionally, factors like material type, preparation method, and measurement error can cause discrepancies in mechanical properties, affecting evaluation accuracy. Consequently, this paper constructed SVR fusion models using three ensemble learning methods to enhance robustness on differentiated data. It investigated the impacts of ensemble methods, ensemble levels, and perturbation levels on the model. The study found that the Bagging-ensembled SVR performed optimally, with R2, MAE, and RMSE of 0.951, 0.369, and 0.560, respectively, exhibiting better robustness on perturbed datasets. This study contributes to resource utilization in mining waste.

One-Step Hydrothermal Deposition of AgSbS2-xSex Thin Films for Solar Cell Applications.

AgSbS2-xSex is a promising light-harvesting material for thin film solar cells, characterized by nontoxicity, high chemical stability, and excellent optoelectronic properties. However, the complex chemical composition of AgSbS2-xSex poses significant challenges to thin film preparation, giving rise to an intensive dependence on multi-step preparation methods. Herein, a hydrothermal method is developed for depositing AgSbS2-xSex films and achieves one-step preparation of this kind of thin film materials for the first time. This method can provide sufficient energy for atomic nucleation and adsorption on the substrate surface to promote nuclei aggregation and grow into films. Meanwhile, it achieves control of the chemical kinetics of the deposition solution by introducing EDTA-2Na as an additive and suppressing the enrichment of Ag2Se impurities at the substrate interface. As a result, a high-purity AgSbS2-xSex film with compact and flat morphology is prepared and assembled into solar cells. The device delivers a power conversion efficiency of 3.04% under standard illumination, which is currently the highest efficiency for AgSbS2-xSex solar cells fabricated by the one-step method. This study provides a facile and promising method for the controllable preparation of high-quality AgSbS2-xSex thin films and promoting their application in solar cells.

Anesthetic recovery outcomes after 2 methods of nasal mucosal preparation for endoscopic sinus surgery

PurposeOur institution uses two approaches for nasal mucosal preparation during endoscopic sinus surgery (ESS) to improve surgical field visualization: topical epinephrine (TE) versus topical cocaine with injection of lidocaine containing epinephrine (TCLE). We aimed to compare anesthetic outcomes after ESS using these techniques. Methods and materialsWe retrospectively identified adult patients at our institution who underwent ESS from May 2018 through January 2023 under general anesthesia with propofol and remifentanil infusions. Postoperative anesthetic outcomes, including pain and recovery time, were compared between patients who had mucosal preparation with TE versus TCLE using inverse probability of treatment weighting (IPTW) to adjust for potential confounders. ResultsAmong 1449 patients who underwent ESS, 585 had TE, and 864 had TCLE. Compared with TE, during anesthetic recovery, the TCLE group had fewer episodes of severe pain (numeric pain score ≥ 7) (IPTW-adjusted odds ratio, 0.65; 95 % CI, 0.49–0.85; P = .002), less opioid analgesic administration (IPTW-adjusted odds ratio, 0.55; 95 % CI, 0.44–0.69; P < .001), and shorter recovery room stay (IPTW-adjusted ratio of the geometric mean, 0.90; 95 % CI, 0.85–0.96; P = .002). Postoperative nausea and vomiting and postoperative sedation were similar between groups. ConclusionsPatients who received preparation of the nasal mucosa with TCLE, compared with TE, were less likely to report severe pain or receive an opioid analgesic in the postanesthesia recovery room and had faster anesthetic recovery. This observation from our large clinical practice indicates that use topical and local anesthetic during endoscopic sinus surgery may have benefit for ambulatory ESS patients.

Exploring the Impact of Visual Heat Conduction Paths on Thermal Conductivity of Polymer Composites and the Practical Applications.

The theory of heat conduction paths has been widely recognized and widely studied in the research about the thermal conductivity of thermal conductive polymer composites at present. Encapsulating polymer pellets with thermally conductive fillers and processing them into thermally conductive polymer composites is a simple and effective method for constructing heat conduction paths. It is meaningful to investigate the related heat conduction mechanism of this method. Otherwise, this approach can significantly preserve the performance of the polymer substrate, making it highly valuable for practical material applications. In this work, polyethylene-octene elastomer (POE) pellets were encapsulated with thermal conductive fillers by physical absorption. Subsequently, the composite films containing heat conduction paths were fabricated using the encapsulated POE pellets through a heating press. Alumina (Al2O3), boron nitride (BN), and alumina/boron nitride hybrid (Al2O3/BN) fillers were used to prepare Al2O3@POE, BN@POE, and BN/Al2O3@POE composite films to investigate the influence of filler shapes on heat conduction path construction. The influence of the constitute and density of heat conduction paths on the thermal conductivity of composite films was analyzed by infrared thermal imaging, finite element analysis, and thermal resistance theory in detail. Owing to the reserved good adhesion and flexibility of the POE substrate, the composite films could be directly used as thermal interface materials for chip cooling, which presented a good heat dissipation effect. Furthermore, a series of integrated composite materials were prepared by the combination of encapsulated pellets with various functional films (copper foil, aluminum foil, and graphite sheet) through a one-pot heating press, exhibiting a good electromagnetic shielding effect. The performance of the composites and the corresponding preparation method demonstrate the strong significance of this research for practical applications.

Progress and Prospect of Sn‐based Metal‐organic Framework Derived Anode Materials for Metal‐ion Batteries

AbstractIn order to realize the growing demand for superior energy storage devices and electric vehicles, commercial anode candidates for next‐generation rechargeable batteries need to meet the characteristics of low cost, high energy density, high capacity, and stable performance. The emerging tin‐based anodes show great potential for high performance metal‐ion battery anodes due to their high theoretical capacity, low cost, green harmless and high safety. Tin based anode materials include tin gold based materials, tin alloy materials, tin based oxides, tin based phosphide, tin based sulfides, multi‐component composite materials, etc. However, the change in volume and structure of tin‐based anode materials during the cycle has become the biggest obstacle to its development. Metal‐organic frameworks (MOFs) provide a wide range of possibilities for achieving high rate capacity and excellent cycle stability by finely regulating the structure and composition of tin‐based materials at the molecular level. The latest progress of tin‐based materials derived from MOFs as anode materials for metal‐ion batteries (including lithium ion batteries, sodium ion batteries, potassium ion batteries, magnesium ion batteries) was reviewed in this paper. Firstly, the preparation method and morphology control of tin‐based MOF are briefly introduced, and the structural characteristics, storage mechanism and modification of tin‐based MOF derived materials are emphatically discussed. Finally, we summarized the existing modification measures and challenges of these anode materials, and put forward the prospect of the future.

Access to 1,3- and 1,5-disubstituted 1,2,4-triazoles by condensation of acyl hydrazides with formamidinium acetate

A simple redox-neutral method for the regioselective preparation of 1,3- and 1,5-disubstituted 1,2,4-triazoles from the corresponding unactivated acyl hydrazides and the inexpensive, non-toxic and shelf stable formamidinium acetate was developed. The addition of zinc salts proved to be pivotal to ensure full regioselectivity for the 1,3-disubstitution pattern, while 1,5-disubstituted 1,2,4-triazoles could be accessed without. A variety of sensitive functional groups were tolerated, and [1,2,4]triazolo[4,3-a]pyridines were obtained from the corresponding 2-hydrazopyridines without Dimroth rearrangement.

Methods for analysis and monitoring of heavy metals in the environment

This review surveys capabilities of modern instrumental analytical methods that provide low limits of detection for a wide range of elements. Some elements have their own toxic forms, so their identification is of particular importance. Researchers pay increased attention to the content of cadmium and lead due to their high immediate and delayed toxicity.It should be noted that those instrumental methods of analysis that are used to determine these important ecotoxicants are often used to determine other heavy metals. The following objects of analysis are considered – natural, river, sea waters; brines; bottom sediments; plants, including medicinal ones; precipitation; soil; as well as whole blood and blood serum; hair and animal fur; animal organs and tissues. Special attention is paid to eliminating matrix influences and reducing limits of detection using concentration procedures. Various types of extraction, sorption, precipitation, chemical transformation (hydride generation, etc.) are considered and applied to biological and environmental objects.The capabilities of modern instrumental methods of analysis for the determination of heavy metals and important ecotoxicants are considered and compared – single‐element (ETAAS, IVA, etc.) and multi‐element (ICP AES, ICP MS, XRF, etc.). The data is structured in the form of a table, which shows specific analysis methods, indicating the method of sample preparation and/or features of instrumental determination, a list of elements to be determined and the limits of detection.

Functional Nutrients and Jujube-Based Processed Products in Ziziphus jujuba.

Jujube (Ziziphus jujuba Mill.) is the first tree species in China, with a long history and abundant yield. However, fresh jujubes have a short shelf-life and are not resistant to storage. Therefore, more and more processed jujube products are being studied. These processed products can extend the shelf-life of jujubes and attract widespread attention for their rich functional nutrients. This review summarized changes in nutrients of fresh jujube and processed products and the research progress of different preparation methods of jujubes. Meanwhile, the pharmacological effects of bioactive components in jujube-based products were concluded. Jujube and its processed products contain rich polysaccharides, vitamin C, and other functional nutrients, which are beneficial to humans. As the initial processing method for jujubes, vacuum freezing or microwave drying have become the most commonly used and efficient drying methods. Additionally, processed jujube products cannot be separated from the maximum retention of nutrients and innovation of flavor. Fermentation is the main deep-processing method with broad development potential. In the future, chemical components and toxicological evaluation need to be combined with research to bring consumers higher quality functional jujube products and ensure the sustainable development of the jujube industry.

Thermally conductive silver adhesive enhanced by MXene@AgNPs with excellent thermal conductivity for thermal management applications

The Thermal Conductive Silver Adhesive (TCSA) efficiently transfers heat from electronic components to heat dissipation components, preventing overheating and extending device lifespan. Despite the effectiveness of commercial sintered nano TCSA, high production costs necessitate a more affordable, high-performance preparation method. This study presents a strategy for preparing ultra-high thermal conductivity (TC) TCSA using multidimensional thermal conductive fillers and low-temperature sintering of silver nanoparticles (AgNPs). MXene@AgNPs particles are synthesized via in-situ reduction of AgNPs on MXene surfaces. These particles, combined with silver microflakes (AgMFs) as primary fillers and epoxy (EP), undergo low-temperature heat treatment to form the AgMFs-MXene@AgNPs/EP composite. Characterization and computational models show that filler-filler interface thermal resistance (ITRf-f) is critical for TC. Adding MXene alone is insufficient, but using MXene@AgNPs particles as secondary fillers allows AgNPs to interconnect fillers, effectively reducing the ITRf-f. The resulting composite achieves an ultra-high TC of 65.51 Wm−1K−1 with 63 wt% total filler content (60 wt% AgMFs, 3 wt% MXene@AgNPs). This study advances the development of low-cost, high-performance TCSA for thermal management applications.

Intrinsic CO2 nanobubbles in alkaline aqueous solutions

Nanobubbles (NBs) and their derivative, bulk nanobubbles (BNBs), have been widely studied due to their potential wide range of applications. However, the stable existence of intrinsic NBs and BNBs in solutions is still controversial. This study investigates the existence and behaviour of unknown nano-entities in dilute alkaline solutions using Flow Field Fractionation Multi-Angle Light Scattering (FFF-MALS), resulting in the first report of the presence, size distribution, and size distribution changes under different treatments. The results suggest that neutral and acidic pure solutions of salts at concentrations below the solubility product do not contain detectable nano entities. Alkaline solutions, on the other hand, such as carbonate buffer and sodium hydroxide, do contain nano scatterers in the range of ~100nm diameter that cannot be removed by boiling or filtration. Reducing the pH of the solutions or freezing reduces their number densities. The freeze-thaw procedure strongly suggests that these nano entities are BNBs. Zeta Nanoparticle Tracking Analysis (ZNTA) shows the zeta potential and the concentration in agreement with previous literature. It can be concluded that intrinsic BNBs in alkaline solutions are an integral part of the total nano-entity population. This study highlights the importance of considering intrinsic BNBs when investigating nanoparticles in alkaline solutions with analytical methods such as Static Light Scattering (SLS), which can detect low number densities in the original liquid state that may not be plausible by other detection methods due to their detection thresholds or acquisition of sample preparation methods of drying or freezing that do not allow real-time observations.

Combined matrix-assisted laser desorption/ionisation-mass spectrometry imaging with liquid chromatography-tandem mass spectrometry for observing spatial distribution of lipids in whole Caenorhabditis elegans.

Matrix-assisted laser desorption/ionisation-mass spectrometry imaging (MALDI-MSI) is a powerful label-free technique for biomolecule detection (e.g., lipids), within tissue sections across various biological species. However, despite its utility in many applications, the nematode Caenorhabditis elegans is not routinely used in combination with MALDI-MSI. The lack of studies exploring spatial distribution of biomolecules in nematodes is likely due to challenges with sample preparation. This study developed a sample preparation method for whole intact nematodes, evaluated using cryosectioning of nematodes embedded in a 10% gelatine solution to obtain longitudinal cross sections. The slices were then subjected to MALDI-MSI, using a RapifleX Tissuetyper in positive and negative polarities. Samples were also prepared for liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis using an Exploris 480 coupled to a HPLC Vanquish system to confirm the MALDI-MSI results. An optimised embedding method was developed for longitudinal cross-sectioning of individual worms. To obtain longitudinal cross sections, nematodes were frozen at -80°C so that all worms were rod shaped. Then, the samples were defrosted and transferred to a 10% gelatine matrix in a cryomold; the worms aligned, and the whole cryomold submerged in liquid nitrogen. Using MALDI-MSI, we were able to observe the distribution of lipids within C. elegans, with clear differences in their spatial distribution at a resolution of 5μm. To confirm the lipids from MALDI-MSI, age-matched nematodes were subjected to LC-MS/MS. Here, 520 lipids were identified using LC-MS/MS, indicating overlap with MALDI-MSI data. This optimised sample preparation technique enabled (un)targeted analysis of spatially distributed lipids within individual nematodes. The possibility to detect other biomolecules using this method thus laid the basis for prospective preclinical and toxicological studies on C. elegans.

Unraveling the myth: immunocytochemistry applications in thyroid lesions.

Fine needle aspiration cytology serves as an important preoperative diagnostic tool for thyroid nodules. Despite its excellent diagnostic accuracy, diagnoses based solely on morphological observation can be challenging. Therefore, various ancillary diagnostic techniques have been applied, including immunocytochemistry (ICC). This review discusses the application and evaluation of ICC in thyroid fine needle aspiration. Currently, three immunostaining preparation methods are available for cytological materials: liquid-based cytology, cell block, and cell transfer. ICC proves valuable in scenarios such as tumour diagnosis, assessment of differentiation and grading of carcinomas, estimation of primary organs in metastatic carcinomas, and detection of gene abnormalities. However, ICC, while useful, is not as accurate as immunohistochemistry and is more difficult to evaluate. If the pitfalls and limitations are understood and effectively navigated, ICC could play a significant role in decreasing the non-diagnostic rate, thus leading to more accurate and valuable diagnoses and reductions in the re-aspiration rate.

The Effects of Different Seed Rates on Yield and Economical Feasibility of Mustard (Brassica juncea)

Rapeseed-mustard plant (Brassica juncea)” is any one of several plant species in the genera Brassica, Rhamphospermum and Sinapis in the family Brassicaceae (the mustard family). Mustard seed is used as a spice. Grinding and mixing the seeds with water, vinegar, or other liquids creates the yellow condiment known as prepared mustard. The seeds can also be pressed to make mustard oil, and the edible leaves can be eaten as mustard greens. Many vegetables are cultivated varieties of mustard plants; domestication may have begun 6,000 years ago. Mustard is a popular condiment, commonly it is a popular condiment made from the seeds of the mustard plant. It can be prepared using white/yellow mustard, brown mustard, or black mustard seeds mixed with liquids, salt, and other flavorings to create a paste or sauce. Mustard pairs well with meats, vegetables, and cheeses and is commonly used in sandwiches, hamburgers, and hot dogs. It is also used in dressings, glazes, sauces, and marinades around the world. The word "mustard" has origins in Latin and French, and archaeological evidence suggests mustard cultivation dates back to ancient civilizations like the Indus Valley. Mustard has a long history of culinary use, with the Romans likely being the first to experiment with mustard as a condiment. In France, Dijon became a renowned center for mustard making, and Dijon mustard is still highly regarded today. Mustard has various uses, such as a condiment, an ingredient in sauces and soups, and an emulsifier in dishes like Hollandaise sauce. The flavor and heat of mustard depend on the seed type and preparation method. Mustard offers nutritional benefits such as vitamins, minerals, and omega-3 fatty acids. Mustard plants is used for producing edible oil for human, oil-cake for feeding animals, sauce, spices, medicine and other purposes in Afghanistan. Mustard has a long history in Afghanistan and is mostly cultivated in the Northern provinces such as Baghlan, Kunduz, Thakkar, Samangan and etc. For the above-mentioned importance of Mustard, we decided to apply a research on seed rates to fine the desirable seed rate of mustard crop for Afghan Mustard growers. Seed rates are one of the important factors, which the suitable seed rates prevent from the economic loss of farmers. This research accomplished in the title of “The effects of different seed rates on yield and growth components of mustard (Brassica juncea)” The research was designed in a complete block design (RCBD) with three replications and five treatments. The data were collected from growth parameters such as plant height, number branches plant-1, number of leaves plant-1 as well as yield parameters such as number of pods plan-1, number of seeds plant-1, seed yield kg ha-1, dry matter kg ha-1 and biological yield kg ha-1. The collected data were analyzed using excel, OPSTAT online testing program, statistical tool for agricultural research (STAR). Based on the statistical analysis the significant differences were observed in all parameters at (P≥0.05. Least significant difference (LSD) was used to compare treatments. A positive correlation was also recognized between growth and yield parameters. Mostly treatment three (15 cm) space between rows performed high influence then the other treatments. We recommend much more research to find the best space between plant to plant and row to row. For the moment the farmers of Afghanistan can use the result of this research on their field for obtaining high yield from Mustard.

Anisotropic thermally conductive films based on two‐dimensional nanomaterials

AbstractThe significant advancement of high‐power densification and miniaturization in modern electronic devices has attracted increasing attention to effective thermal management. The primary objective of thermal management is to transfer excess heat from electronics to the outside environment through the use of thermal conductive materials. The anisotropic thermally conductive films (TCFs) based on two‐dimensional (2D) nanomaterials exhibit outstanding controlled heat transfer capability, which effectively removes hotspots along the in‐plane direction and provides thermal insulation along the cross‐plane direction. However, a comprehensive review of anisotropic TCFs is rarely reported. Herein, we first discuss the intrinsic anisotropic thermal conductivity of 2D nanomaterials for preparing TCFs. Then, the preparation methods and anisotropic thermal conductivity of TCFs have been summarized and discussed. Furthermore, we conclude with the practical applications of TCFs for anisotropy thermal management. Finally, a conclusion of the challenges and outlook of TCFs is provided to promote their development in future scientific research.

Assessment of the effects of the use of preconsumer cotton waste on the quality of rotor yarns

Due to the shortage of raw fiber materials and stricter legislative conditions, it has become necessary to process even the more contaminated fiber wastes that contain only a small amount of useable fibers. Hence, this paper investigates the impact of different cleaning channels on the Rieter R37 rotor spinning machine in controlling spinning strategy and yarn quality using recovered blowroom cotton waste fibers. The study involves spinning 98-tex yarns with different cleaning channels during the spinning process, using recovered blowroom cotton waste in blends with virgin cotton processed into slivers by two methods. Qualitative indicators in the fiber-sliver-yarn line were evaluated and graphically compared. The statistical significance of the influencing factors was determined using the Generalized Anova. Additionally, the quality of the experimental samples was compared to authentic data from global production using the USTER® STATISTIC. The results underline the significant influence of fiber quality, sliver preparation method and implemented cleaning channels on the arrangement of fibers in yarn structures as evidenced by structural and mechanical parameters. In particular, the comparison with USTER® STATISTICS confirms that all yarns meet the required quality standards for selected applications, including those spun exclusively from 100 % cotton waste. Furthermore, the results demonstrate that this innovative technology enables yarn manufacturers to meet customer demands, ensure optimal yarn quality and achieve cost savings by optimizing waste removal without compromising fiber yield.

Optimization of Sample Preparation Procedure for Determination of Fat-Soluble Vitamins in Milk and Infant Food by HPLC Technique

Background: The analysis of vitamins in baby food is a challenging task given the complexity of the food matrix, vitamin stability, and strict regulations of the European Union regarding permissible deviations from declared values. Vitamins in food exist in different concentrations and forms and have different stabilities; thus, the preparation of samples for a reliable analysis using the same procedure is not straightforward. Therefore, significant attention has been devoted to optimizing sample preparation in the analysis of vitamins. Methods: This study aims to determine which of the sample preparation and extraction methods is the most efficient for the simultaneous determination of vitamins A, D, E, and K in milk and baby food using high-performance liquid chromatography (HPLC). Different samples of baby food were prepared in seven different ways based on four methods (saponification, enzymatic hydrolysis, solvent extraction, and solid-phase extraction). Results and Conclusion: According to the validation parameters, the optimal preparation method proved to be solid-phase extraction with a C18 stationary phase, with recoveries of 97.4%, 96.1%, 98.3%, and 96.2% for vitamins A, D, E, and K, respectively, and HPLC with a UV–Vis detector was identified as a sufficiently sensitive technique for the identification and quantification of fat-soluble vitamins in milk and baby food.

Ion Chromatography and Related Techniques in Carbohydrate Analysis: A Review.

Ion chromatography and related techniques have been the most popular separation methods used in the determination of organic and inorganic anions and cations, predominantly in water and wastewater samples. Making progress in their development and introducing new stationary phases, methods of detection and preparation of samples for analyses have given rise to the broadening of their analytical range. Nowadays, they are also used for substances that are not ionic by nature but can convert to such forms under certain conditions. These encompass, among others, carbohydrates, whose role and significance in humans' lives and environment is invaluable. Their presence in the air is mostly due to the industrial burning of biomass for energy production purposes. In addition, the content of sugars in plants, fruits and vegetables, constituting the base of human diets, affects our health condition. Given that, there is not only a need for their determination by means of routine methods but also for searching for novel analytical solutions. Based on literature data from the past decade, this paper presents the possibilities and examples of applications regarding ion chromatography and related techniques for the determination of carbohydrates in environmental samples, biomass and plants constituting food or raw materials for food production. Attention has been paid to the virtues and limitations of the discussed separation methods in this respect. Moreover, perspectives on their development have been defined.