Reference Materials Research Articles

Development of New Series of Certified Reference Materials for Ferrosilicon Magnesium Alloys

This paper presents a practical approach to the production of certified reference materials (CRMs) for ferrosilicon magnesium alloys. These new CRMs are predicted to be used in fast X-ray fluorescence spectrometry (XRF) analysis, which does not require sample digestion and does not result in the production of acidic sewage and emissions, contrary to the classical and instrumental techniques currently used in laboratories. Four new certified reference materials (CRMs) were developed to fill the gap in the reference materials market and ensure fast and traceable analyses. The materials were produced with an industrial process and then homogenized and mixed to achieve the required compositions and level of homogeneity. The homogeneity was determined using specially developed analytical methods and confirmed statistically by ANOVA. Additionally, the results of the tests show the short- and long-term stabilities of the new materials. The certified values for specific element contents were determined in interlaboratory tests. All results were assessed statistically for outliers. The results from three or more independent and different analytical methods were used for the calculations. In parallel homogeneity, the stability, and characterization standard uncertainties were calculated and used in the estimation of the final expanded uncertainties of the certified values. Finally, four new CRMs were assisted with the proper certificates according to ISO standards.

Determinants of Unwanted Pregnancy in Indonesia in 2022

Unwanted pregnancy in teenagers is the impact of deviant sexual behavior. Adolescents with Unwanted pregnancy are faced with various problems, especially health problems for mothers and babies, and socio-economic problems. This research aims to examine the determinants of untimely pregnancy in adolescents in North Konawe Regency. The research design uses a Cross Sectional Study conducted in September 2022-February 2023 in three randomly selected sub-districts of North Konawe Regency. A total of 80 teenage girls aged 14-19 years who experienced untimely pregnancy were sampled. The research uses a structured questionnaire technique guided by researchers which has been previously tested and analyzed using the Fisher Exact test. The results of the bivariate analysis showed that the variables were Knowledge (p=0.568>0.05), Attitude (p=0.002<0.05), Action (p=0.74>0.05), Permissive Parenting Pattern (p=0.109>0.05), Peer Pressure Peers (p=0.592>0.05), Use of Technology (p=0.034<0.05) and Religiosity (p=0.001<0.05). The results of this research show that there is a relationship between Attitude, Use of Technology and Religiosity, and there is no relationship between Knowledge, Action, Permissive Parenting Patterns and Peer Pressure with Unwanted Pregnancy in teenagers in the North Konawe Regency Area. Thus, the Reproductive Health Education program for Adolescents in formal education involves education stakeholders including the School Committee which is a reference material and a program to reduce the number of unwanted pregnancy in adolescents in the North Konawe Regency area.

A versatile ratiometric fluorescence nanoprobe for the determination of clonazepam in patients' plasma samples.

Despite the necessity of the study of therapeutic drug monitoring of clonazepam (CLZ), there are only a few fast detection methods available for determining CLZ in biological media. This study aims to develop a cost-effective and ratiometric probe for the quantification of CLZ in plasma samples. Fluorescent polydopamine nanoparticles were produced through a self-polymerization process at a pH of 8.5. Rhodamine B molecules were employed as a fluorescent reference material, emitting stable fluorescence in the visible range. The fabricated probe exhibited a specific detection capability for CLZ. The fluorescence emission of the probe was enhanced in two concentration ranges: from 50 ng/mL to 1.0 μg/mL and from 1.0 to 15.0 μg/mL with a lower limit of quantification of 50 ng/mL, indicating the sensitivity of the probe for detecting CLZ plasma levels. The accuracy of the probe is favorable which could be recommended for CLZ monitoring in the biological media. Furthermore, this probe is highly specific towards CLZ in the presence of various interfering agents which is mainly caused by its ratiometric nature. The developed platform showed high reliability in quantifying CLZ concentrations in patients' plasma samples. Hence, the fabricated probe could be recommended as a reliable method for the routine detection of CLZ in clinical settings.

Efficient Quality Control of Peptide Pools by UHPLC and Simultaneous UV and HRMS Detection

Peptide pools consist of short amino acid sequences and have proven to be versatile tools in various research areas in immunology and clinical applications. They are commercially available in many different compositions and variants. However, unlike other reagents that consist of only one or a few compounds, peptide pools are highly complex products which makes their quality control a major challenge. Quantitative peptide analysis usually requires sophisticated methods, in most cases isotope-labeled standards and reference materials. Usually, this would be prohibitively laborious and expensive. Therefore, an approach is needed to provide a practical and feasible method for quality control of peptide pools. With insufficient quality control, the use of such products could lead to incorrect experimental results, worsening the well-known reproducibility crisis in the biomedical sciences. Here we propose the use of ultra-high performance liquid chromatography (UHPLC) with two detectors, a standard UV detector at 214 nm for quantitative analysis and a high-resolution mass spectrometer (HRMS) for identity confirmation. To be cost-efficient and fast, quantification and identification are performed in one chromatographic run. An optimized protocol is shown, and different peak integration methods are compared and discussed. This work was performed using a peptide pool known as CEF advanced, which consists of 32 peptides derived from cytomegalovirus (CMV), Epstein–Barr virus (EBV) and influenza virus, ranging from 8 to 12 amino acids in length.

РАЗВИТИЕ ВЗГЛЯДОВ НА СТРАТЕГИЧЕСКОЕ УПРАВЛЕНИЕ ЧЕЛОВЕЧЕСКИМИ РЕСУРСАМИ В ДРЕВНЕКИТАЙСКОЙ ИДЕОЛОГИИ КОНФУЦИАНСТВА

Based on the research of two Confucian scholars of the ancient Chinese school of management thought, Confucius and Meng-tzu, this work provides an academic analysis and a general description of their work, discusses the differences between different types of management thought in order to clarify the principles of management described in it, and finally, the causes and factors leading to the development of and the change of managerial thought, which can be used as a reference material for research by students studying management, and it has a certain reference value for the development of a strategic view of human resource management of the ancient Chinese school of management thought.

Certification of Meissen Granite IAG GMN‐1 Using the GeoPT Proficiency Testing Certification Protocol

Following a full assessment of the GeoPT proficiency testing scheme against the recommendations in ISO Guide 35:2017 for the use of proficiency testing in the certification of reference materials, this paper presents the first application of the GeoPT certification protocol in the characterisation of a new geochemical CRM, IAG GMN‐1, Meissen Granite. This protocol is applied to the measurement results reported in Round 51 of the GeoPT programme in which the candidate CRM was used as the test material, together with an established CRM (CGL 008 MGT‐1 Granite) to provide validation of the results. Following the presentation of mineralogy, grain‐size analysis and homogeneity testing data for IAG GMN‐1, certified values for nine major elements and thirty‐nine trace elements are reported.

Revolutionizing scandium detection in real samples: Unleashing the power of sol-gel-based optical sensor.

The development of a highly selective and ultra-sensitive optical sensor for detecting scandium (Sc3+) ions involves incorporating the reagent 2,3-dichloro-6-(3-carboxy-2-hydroxy-1-naphthylazo)quinoxaline (DCHNAQ) into a silica sol-gel thin film on a glass substrate. This innovative approach utilizes tetraethoxy-silane (TEOS) as the precursor, maintaining a sol-gel pH level of 4.5, a water-to-alkoxide ratio of 5:1, and a DCHNAQ concentration of 5.0 × 10-4M. A detailed exploration of the impact of sol-gel parameters on the sensing capabilities of the developed sensor has been meticulously undertaken. This innovative sensor demonstrates remarkable selectivity in evaluating Sc3+ ions over a dynamic range of 7.5-170ng/mL, with limits of quantification and detection recorded at 7.3 and 2.20ng/mL, respectively. Consistent results are achieved with a minimal RSD of 1.47 and 0.94% for Sc3+ ions at 50 and 100ng/mL, respectively, coupled with a swift response time of three min. Assessments of interference demonstrate a noteworthy preference for Sc3+ions, accomplished by enclosing DCHNAQ within the sol-gel framework and making optimal structural modifications to the doped sol-gel. The sensor offers straightforward regeneration using a 0.25M EDTA solution, exhibiting complete reversibility. Comparative analysis with other methodologies underscores the efficacy in determining Sc3+ions in various reference materials, including plant leaves, fish, water, alloys, ores, and monazite samples.

International comparisons in the field of measurement of specific adsorption of gases and specific surface area of solids: the optimal amount to ensure calibration and measurement capabilities

Indicators of the accuracy of measurements of the most important characteristics of the structure of porous and dispersed materials - specific adsorption of gases, specific surface area, specific pore volume and pore size – are considered. The performance of sorbents, catalysts and membranes in the chemical and petroleum industries, including the purification of substances and materials, depends on the values of these characteristics. It has been established that for mutual recognition of national standards and certificates of calibrations and measurements of porosity characteristics of solid substances performed by national metrological institutes, it is required to organize and successfully participate in three international key comparisons under the auspices of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology of the International Bureau of Weights and Measures. The results of the participation of national metrology institutes and designated organizations of Germany, China, Japan, Brazil, Turkey and Russia in three international key comparisons in the field of measurements of specific adsorption of gases (nitrogen, argon, krypton) and specific surface area of solids (zeolite, silicon oxides and aluminum) are presented. Carrying out the optimal number of comparisons makes it possible to register in the Key Comparison Database of the International Bureau of Weights and Measures the measuring and calibration capabilities of the national metrological institutes of the participating countries for various matrices in a wide range of measurements of specific adsorption of gases 0.001–25 mol/kg and specific surface area of solids 0.1–1500 m2/g. Based on the results of these three international key comparisons, 18 of broad calibration and measurement capabilities of the Russian participant, the D. I. Mendeleev Institute for Metrology, were entered into the Key Comparison Database; two of these items are currently undergoing examination, including reference materials produced by this institute. A comparative analysis of the results of measurements of the specific surface area of solids using nitrogen and krypton as adsorbates was performed. It has been established that the uncertainty of the measurement results of the specific surface area is significantly less in the case of using krypton as an adsorbate with a specific surface area of less than 1 m2/g, which is due to the higher values of the relative pressure of krypton compared to nitrogen. The use of calibration and testing laboratories in Russia of certified reference materials of sorption properties presented in the Key Comparison Database of the International Bureau of Weights and Measures will ensure metrological traceability in the field of measurements of porosity characteristics.

Effect of surfactants on the degree of polydispersity of a suspension of polystyrene latex spheres

The problem of satisfying the needs of the domestic market of the Russian Federation for creating domestic particle size standard reference materials in liquids to ensure uniformity in measurements of the granulometric composition of aerosols and powdery substances is considered. It is known that, under various conditions, monodisperse suspensions of polystyrene latex spheres can be synthesized, both monodisperse and polydisperse samples being obtainable. The effect of the composition and solubility of surfactants in a styrene-based water emulsion on the particle size of suspensions obtained as a result of emulsion polymerization, and their polydispersity, has been investigated. The metrological characteristics of polystyrene suspensions based on sodium, potassium, and lithium laureths synthesized in this study were determined using dynamic light scattering and laser diffraction techniques. It has been found that the size and degree of polydispersity of particles in suspensions based on lauric acid salts is primarily influenced by the solubility of the surfactant and the surface tension of the interfacial layer formed between styrene and water at the time of particle formation. The effect of the rate of reaction, as well as the concentration of surfactants, on the size and polydispersity of the synthesized particles, has been studied. It has been found that when potassium persulfate is used as the initiator in the reaction, particle size distributions are monodisperse for suspensions based on sodium or potassium laureate. The polydispersity degree of lithium laureate-based suspensions is approximately 1.5 to 2 times higher compared to other suspension samples. When azoisobutyronitrile is used as an initiator, all suspensions samples are monodisperse. It has been experimentally determined that the achievement of monodisperse samples is due to the polymer-monomer particle formation time, which is comparable to the monomer transformation rate. The results obtained will be utilized in the development and establishment of particle size standard reference materials for storage and reproduction of particle size values within a liquid medium.

Alcohol policy development in Sierra Leone: An assessment of the role of civil society

Objective: To assess the value addition of civil society collaboration with Government in the development of Sierra Leone’s National Alcohol Policy (NAP). Policy Development Process: We reviewed the entire process of lobby, advocacy, and support for the development of the NAP from 2015 when the Siera Leone Alcohol Policy Alliance (SLAPA) was formed to the launch of the NAP in 2023. It also assesses the level of collaboration between FoRUT, SLAPA and Ministry of Health of Health and Sanitation (MoHS). The MoHS coordinated the policy formulation process with substantive technical support from civil society. Results: The quality of the NAP was rated high as it reflected appropriate policy areas and interventions from the Global Strategy to Reduce the Harmful Use of Alcohol, the WHO SAFER initiative, and the Global Action Plan for Alcohol Control (202-2030). The NAP is a solid reference material for the development of a new alcohol bill. MoHS recognized FoRUT and SLAPA as the national champions for alcohol control in the country. FoRUT, directly and through SLAPA influenced the process of developing the NAP and its quality through advocacy, collaboration and technical and financial support. Conclusions: The development of the NAP in Sierra Leone truly reflects civil society-government collaboration, built on mutual trust and a common health and development agenda. Connecting national level lobby and advocacy with regional global advocacy actions to prioritize, influence, support, and monitor the alcohol control agenda is a critical catalyst for civil society to advancing the development of NAPs.

Using Bland-Altman plot-based harmonization algorithm to optimize the harmonization for immunoassays.

Harmonization has been recommended by theInternational Organization for Standard (ISO) to achieve equivalent results across invitro diagnostic measurement devices (IVD-MDs). We aim to evaluate the effectiveness of Bland-Altman plot-based harmonization algorithm (BA-BHA) created in this study and compare it with weighted Deming regression-based harmonization algorithm (WD-BHA) proposed in ISO 21151:2020. Eighty patient sera were used as the harmonization reference material (HRM) to develop IVD-MD-specific harmonization algorithms. Another panel of 40 patient sera was used to validate the effectiveness of harmonization algorithms. We compared regression slopes, intercepts, Bland-Altman plot layouts, percent differences, limits of agreement (LoAs), between-method coefficients of variation (CV) before and after harmonization. After harmonization by WD-BHA, acceptable slopes and intercepts between measured values and HRM targets were observed in weighted Deming regression, but not in Passing-Bablok analysis. Mean differences were-5.5 to 5.0 % and differences at specific levels were-33.9 to 23.9 %. LoAs were-64.6 to 74.6 %. Between-method CV was 22.9 % (±12.9 %). However, after harmonization by BA-BHA, both weighted Deming and Passing-Bablok regressions equations presented harmonized results. Mean differences were-0.3 to 0.2 % and differences at specific levels were-1.1 to 1.6 %. LoAs were-23.3 to 23.2 %. Between-method CV was 8.4 % (±4.0 %). The data points were evenly distributed at both sides of the mean in Bland-Altman plots. The inequivalence of test results between different methods can be improved but unacceptable analytical differences at specific levels may be hidden in terms of an acceptable slope and intercept on WD-BHA. The new protocol BA-BHA may be a viable alternative to optimize the harmonization for immunoassays.

Greening airports: A methodological framework for site assessment and assessing solar PV potential

Due to energy intensiveness and carbon emissions, the aviation sector is under continuous environmental pressure. In this regard, airports have shown keen interest in solar photovoltaic (PV) technology to decarbonize their energy consumption. Implementing onsite solar projects in the airport is challenging due to various technical and safety aspects. Improper siting of solar PV arrays may adversely affect the safety of the passengers. This paper aims to develop a methodological framework for site assessment and potential estimation of PV projects in airport locations. The developed methodology is applied as a case study to seven Indian airports: Madurai, Goa, Raipur, Ahmedabad, Lucknow, Amritsar, and Dehradun. It was understood that the suitable area for solar PV projects on airport land depends on airspace restrictions, built area, and glare occurrence. On average, 30–40 % of the airport land is observed to be built area; hence, it is unavailable for land-based solar PV systems. Among the studied airports, the highest value of technical potential is observed for Raipur airport (21 MW). These conservative estimates provide baseline information for airport planning and development projects. This study is expected to be a reference material for energy specialists, airport stakeholders, and policymakers.

Improving hydrogen release from oxygen‐functionalized LOHC molecules by Ru addition to Pt/C catalysts

Bimetallic PtRu/C catalysts have been prepared by depositing Ru onto a commercial Pt/C catalyst and subsequent thermal annealing. Different Pt:Ru ratios of 1:1, 2:1, 4:1, 8:1, and 16:1 have been investigated with annealing temperatures of 350 and 500 °C. Using X‐ray diffraction (XRD), synchrotron powder X‐ray diffraction (SPXRD) combined with pair distribution function (PDF) analysis and scanning transmission electron microscopy with energy dispersive X‐ray spectrum imaging (STEM‐EDXS), we show that diffusion of Ru into the fcc crystal structure of the Pt nanoparticles takes place during thermal annealing. Partial segregation and the formation of Pt nanoclusters on the bimetallic surface was observed depending on the Pt:Ru ratio. The annealing process does not only cause a high Pt dispersion but also affects the electronic structure of the Pt surface by broadening the d‐band thus facilitating the product’s desorption from the surface of the bimetallic particle. These beneficial effects have been exemplified for the catalytic dehydrogenation of dicyclohexylmethanol, a promising hydrogen carrier compound with 7.2 wt% hydrogen capacity. The most active catalyst material among the tested supported alloys and monometallic reference materials was Pt4Ru1/C after annealing at 500 °C, which increased the hydrogen release productivity by 65% compared to the unmodified Pt/C catalyst.

Fatigue Behavior of Medium Entropy Alloys AlCrFe<sub>2</sub>Ni<sub>2</sub> and AlCrFe<sub>2</sub>Ni<sub>2</sub>Mo<sub>0.1 </sub>- A Comparison with Super Duplex Steel 1.4517

Fatigue Behavior of Medium Entropy Alloys AlCrFe<sub>2</sub>Ni<sub>2</sub> and AlCrFe<sub>2</sub>Ni<sub>2</sub>Mo<sub>0.1 </sub>- A Comparison with Super Duplex Steel 1.4517

Synergistic effect of Nb and Mo on the microstructural formation of the Ti(C,N)-high chromium ferrous-based cermets

In this study, Ti(C,N)-Fe-based green cermets with different metallic alloying elements have been consolidated by pressureless liquid-phase sintering. The addition of different metallic binders on Ti(C,N)-based cermet such as Nb and Mo on high chromium Ferrous based binder has been investigated. Detailed analysis of the phase constitution was conducted using thermodynamic calculations and experiments, as well as a systematic study of the microstructure evolution and room temperature mechanical properties including hardness and fracture toughness was conducted. The Nb and Mo addition to the binder system affects the sintering temperatures and can significantly affect the phase formation and microstructural development. Scanning electron microscope (SEM) and Energy dispersive spectroscopy (EDS) technique were used to examine the microstructure, composition, and fracture surface of cermets. The addition of the Mo, and Nb reveals lower porosity and finer microstructure as compared to the reference material (Ti(C,N)-Fe-Cr). The refinement of microstructure improves mechanical properties such as hardness and fracture toughness of Ti(C,N)-Fe-Cr-Mo-Nb-based cermets. Further, the addition of these binder elements may reduce the formation of Fe-Cr-based intermetallic complex carbides, allowing cermets to perform better in terms of toughness and corrosion resistance. As a result of the experiments, it is evident that Nb and Mo dissolve in Ti(C,N) and form solid solutions during sintering. The increased number of coreless grains, spinodal decomposition, and crack deflection in cermet further enhance the fracture toughness.

Continuous-Flow Stable Sulfur Isotope Analysis of Organic and Inorganic Compounds by EA-MC-ICPMS.

Elemental analysis (EA) coupled to isotope ratio mass spectrometry (IRMS) is a well-established method to derive stable isotope ratios of sulfur (34S/32S). Conversion of sulfur to SO2 by EA and measurement of SO2 isotopologues by IRMS represents the simplest and most versatile method to accomplish isotope measurement of sulfur even in bulk samples. Yet, interferences by oxygen isotopes in SO2 often impair the precision and trueness of measured results. In the current study, we coupled EA to multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) to establish a method that avoids such interferences due to direct measurement of S+ ions. In addition, measurement of the 33S/32S isotope ratios is possible, thus representing the first bulk method that is suitable to study mass-independent isotope fractionation (MIF). Analytical precision (σ) of available Ag2S and BaSO4 reference materials (RMs) was, on average, 0.2 mUr for δ33S and δ34S, never exceeding 0.3 mUr within this study (1 mUr = 1‰ = 0.001). Measured δ34S values of reference materials agreed within ±0.2 mUr of officially reported values. Measurement of wood samples yielded good precision (0.2 mUr) for sulfur amounts as low as 3.5 μg, but precision deteriorated for samples at lower sulfur contents due to poor peak shape. Finally, we explored cross-calibration of organic liquids separated via gas chromatography (GC) against solid RMs combusted via EA that avoids challenging offline conversion of RMs. Results indicate good precision (≤0.08 mUr) and acceptable trueness (≤0.34 mUr) for determination of δ34S, demonstrating the future potential of such an approach.

Utilization of bis-MPA Dendrimers for the Calibration of Ion Mobility Collision Cross Section Calculations.

Ion mobility-mass spectrometry (IM-MS) has become increasingly popular with the rapid expansion of available techniques and instrumentation. To enable accuracy, standardization, and repeatability of IM-MS measurements, the community requires reliable and well-defined reference materials for calibration and tuning of the equipment. To address this need, synthetic dendrimers of high chemical and structural purity were tested on three ion mobility platforms as potential calibrants. First, synthesized dendrimers were characterized by drift tube ion mobility (DTIMS), using an Agilent 6560 IM-qTOF-MS to assess their drift tube collision cross section (DTCCS) values. Then, assessment of obtained CCS values on trapped ion mobility (TIMS) and traveling wave ion mobility (TWIMS) ion mobility platforms were compared to those found by DTIMS. Across all three systems, dendrimers were found to have high potential for m/z and ion mobility calibration in the CCS range of 160-1700 Å2. To further validate their use as calibrants, drift tube calculated CCS values for dendrimers were utilized to calibrate calculations of CCS for known standards including Agilent Tuning mix, the CCS Major mix from Waters, and SPLASH LIPIDOMIX. Additionally, structures of sodiated dendrimers were computated along with theoretical CCS values which showed good agreement with the experimental CCS values. On the basis of the results presented, we recommend the use of dendrimers as alternatives and/or complementary compounds to commonly used calibrants for ion mobility platforms.

Essential and toxic elements determination in Ampelodesma mauritanicum plant based on gamma-ray spectrometry

Due to the scarcity of data on both basic and toxic chemical elements in medicinal and fodder plants in Algeria, this study focused on evaluating the content of these elements in the Ampelodesma mauritanicum plant grown in the Ghardaia region of Southern Algeria. This plant is commonly used by Bedouins in traditional medicine and as fodder, and has applications in construction, decontamination, and water purification. Based on gamma-ray spectrometry for neutron activation analysis, the study identified and categorized a total of 25 mineral and trace elements into essential, non-essential, and potentially toxic groups. Essential elements exhibited varying concentrations, with potassium being the most abundant, followed by sodium, calcium, iron, zinc, chromium, cobalt, and selenium. The study also assessed potentially toxic elements, all found below the estimated permissible limits established by FAO/WHO. Quality control was ensured through the analysis of certified reference materials. The findings provide valuable insights into the elemental composition of Ampelodesma mauritanicum, offering significant implications for medicinal and nutritional applications while ensuring analytical accuracy and reliability.

Nile red staining for rapid screening of plastic-suspect particles in edible seafood tissues

Concerns regarding microplastic (MP) contamination in aquatic ecosystems and its impact on seafood require a better understanding of human dietary MP exposure including extensive monitoring. While conventional techniques for MP analysis like infrared or Raman microspectroscopy provide detailed particle information, they are limited by low sample throughput, particularly when dealing with high particle numbers in seafood due to matrix-related residues. Consequently, more rapid techniques need to be developed to meet the requirements of large-scale monitoring. This study focused on semi-automated fluorescence imaging analysis after Nile red staining for rapid MP screening in seafood. By implementing RGB-based fluorescence threshold values, the need for high operator expertise to prevent misclassification was addressed. Food-relevant MP was identified with over 95% probability and differentiated from natural polymers with a 1% error rate. Comparison with laser direct infrared imaging (LDIR), a state-of-the-art method for rapid MP analysis, showed similar particle counts, indicating plausible results. However, highly variable recovery rates attributed to inhomogeneous particle spiking experiments highlight the need for future development of certified reference material including sample preparation. The proposed method demonstrated suitability of high throughput analysis for seafood samples, requiring 0.02–0.06 h/cm2 filter surface compared to 4.5–14.7 h/cm with LDIR analysis. Overall, the method holds promise as a screening tool for more accurate yet resource-intensive MP analysis methods such as spectroscopic or thermoanalytical techniques.Graphical

Knowledge mapping of chronic insomnia: a bibliometric analysis (2000-2023).

Recently, significant scientific research breakthroughs have been witnessed in the treatment of chronic insomnia. However, it seems that there is currently no bibliometric analysis of this. Therefore, we hope to comprehensively review and analyze the scholarly system and research focus in the field of chronic insomnia treatment through bibliometric methods. Between 2000 and 2023, we explored various papers in relation to the treatment of chronic insomnia in the Web of Science Core Collection(WOSCC) database. Subsequently, the collected papers were subjected to bibliometric analysis utilizing CiteSpace, VOSviewer, and the "bibliometric" package in R language. With China and the United States(USA) among them, a total of 2937 papers were published across 49 countries. Publications related to the treatment of chronic insomnia were increasing year by year. The Laval University, Washington University, Pittsburgh University, and Stanford University were key research institutions. The journal Sleep was widely popular in the field and was also one of the most cited journals. These papers came from 148 authors, with Morin, Charles M., Roth, Thomas, Espie, Colin A., Harvey, Allison G., and Buysse, Daniel J. publishing the most papers and Morin, cm being co-cited the most. The treatment process of chronic insomnia can be divided into three main stages: drug intervention, diseases related to chronic insomnia, and cognitive behavioral therapy and mental health. Keywords such as "children and adolescents", "novel coronavirus pneumonia" (COVID-19), "mental health" and "heart failure" have become the focus of current research. We carried out a detailed bibliometric review of the development trends and research results of chronic insomnia research through this study for the first time. The information it provides reveals recent research hotspots and cutting-edge issues, providing valuable reference materials for researchers focusing on the treatment of chronic insomnia.