Determination of chlorinated paraffins in PM2.5 by QuEChERS combined with ultra-high performance liquid chromatography-quadrupole/orbitrap high resolution mass spectrometry by Wenyan YAN, Chao WANG, Juan LIU, Yibin SUN, Wen GU, Yifu LU, Ke FANG, Yi WAN, Song TANG

“…Simultaneous extraction and determination of SCCPs, MCCPs, and LCCPs in PM2.5 could provide technical support for their environmental monitoring and human health risk assessment.ObjectiveTo establish a method based on QUEChERS pretreatment method in conjunction with ultra-performance liquid chromatography-quadrupole/orbitrap high resolution mass spectrometry for simultaneously determining the levels of SCCPs, MCCPs, and LCCPs in PM2.5. …”
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Flash glucose monitoring system help reduce the frequency of hypoglycemia and hypoglycemic fear behavior in type 1 diabetes patients by Lining Dong, Junxian Li, Yanyun Hu, Ruoting Chai, Ye Zhu, Liying Zhu, Nengguang Fan, Zhijian Zhang, Jiemin Pan, Jinhua Yan, Fang Liu, Fang Liu

“…The optimal cut-off point for GCV was determined to be 40.55.…”
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Application of novel oligomeric Co(II) complexes of 4,4′-bipyridine and 1,10-phenanthroline modified glassy carbon electrode for differential pulse voltammetric determination of ci... by Mezgebu Biresaw, Adane Kassa, Getinet Tamiru Tigineh, Atakilt Abebe

“…The recovery results for tablet and urine samples ranged from 99.44 % to 99.95 % and 99.25 % to 100.51 %, respectively, with interference recovery showing an error of less than 4.73 %. When it came to determining CPF in tablet formulations and human urine samples, the new approach outperformed recently published voltammetric methods. …”
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On а Model for Drough Risk Reduction in Agriculture by B. A. Ashabokov, L. M. Fedchenko, A. A. Tashilova, L. A. Kesheva, M. B. Ashabokova

“…A model based on different vulnerability of agricultural crops to this dangerous weather phenomenon is presented, the results of model calculations for the conditions of the steppe zone of the Kabardino-Balkarian Republic (KBR) are presented.Materials and research methods. When conducting research, the Selyaninov hydrothermal coefficient was used as an indicator characterizing the moisture content of the soil. …”
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Prevalence and determinants of HIV among reproductive-age women (15–49 years) in Africa from 2010 to 2019: a multilevel analysis of demographic and health survey data by Alemu Gedefie, Amare Muche, Anissa Mohammed, Aznamariam Ayres, Dagnachew Melak, Eyob Tilahun Abeje, Fekade Demeke Bayou, Fekadeselassie Belege Getaneh, Lakew Asmare, Abel Endawkie

“…Thus, the aim of this study was to identify the determinants of HIV among reproductive-age women in Africa.MethodsThis study was conducted among reproductive-age women in Africa, based on secondary data obtained from the Demographic Health Survey (DHS) conducted between 2010 and 2019. …”
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Predicting the critical drainage induced by soil seepage failure during pumping in foundation pit construction by Fuwei JIANG, Shujun TANG, Xiaofei DENG, Zhenchao LI, Fawang ZHANG, Hongyuan YIN

“…To ensure that the calculated result is more effective, the calculated expression was modified by introducing correction coefficient. The results indicate that the relationship between the critical drawdown volume for inducing soil permeability failure in the four cases and the critical permeability velocity is linear, suggesting that measuring the critical permeability velocity of the soil at the site can determine the critical drawdown volume. …”
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Research and Application of an Innovative 110 Mining Method in Gob-Side Half Coal Rock Entry Retaining by Eryu Wang, Xiangdong Chen, Xiaojie Yang

“…First the technical principle and key technology of this mining method was presented. Then, through theoretical analysis and calculation, engineering experience, and field test, the key parameters such as the length of constant resistance anchor cable, the cutting angle and height of presplitting blasting, the charge structure, and the blocking-gangue support structure were determined and conducted in the retained entry. …”
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A general approximation method for accurate evaluation of the intermolecular potential parameters by using density functional theory by Bahtiyar Akber Mamedov, Elif Somuncu, Ebru Karatas

“…In this work, a new approach is developed and presented for determining the intermolecular potential parameters from intermolecular interaction energy data obtained using the Density Functional Theory (DFT) method over a different basis set. …”
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SURFACE OSCILLATIONS IN OPEN RESONATORS WITH CURVILINEAR REFLECTORS by I. K. Kuzmychov, O. S. Lukash, O. B. Senkevych, O. V. Gribovsky

“…The electric field structures of considered oscillation types were measured using the probe-induced perturbation method. The resonant transmission coefficients of the open oscillating systems and the physical phenomena within them were experimentally studied with the aid of well-known microwave measurement techniques. …”
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Areas of energy advantage for flowsheets of separation modes for mixtures containing components with similar volatilities by M. E. Peshekhontseva, M. A. Maevskiy, I. S. Gaganov, A. V. Frolkova

“…The direct and indirect distillation modes can become competitive when the point of the original composition is located near single K-surfaces or in a region with a different ratio of distribution coefficients. Sharp distillation is not suitable for the separation of a mixture containing a pair of components exhibiting relative unity volatility with medium boiling points.Methods. …”
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Finite-element analysis of contact characteristics and friction modes of the "valve-guide" of the internal combustion engine by K.E. Holenko, A.A. Vychavka, M.O. Dykha, V.O. Dytyniuk

“…Based on the constructed finite-element model of the "valve-guide" conjugation, an analysis of the influence of determining tribological factors: sliding speed in contact, temperature, skew angle, friction coefficient on contact stresses both for each part of the friction pair and in the process of contact interaction was carried out. …”
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EVALUATION OF SUBSOIL MASSIF STABILITY TAKING INTO ACCOUNT THE IRREGULARITY OF CONSTITUENT ROCKS ON THE BASIS OF A RANDOM SIZE AND FUNCTION MODEL by M. O. Allaev

“…The use of the random function model when solving the problem of forecasting the stability of the massif enables the evaluation of such important parameters of the safe development of the landslide process as probability of occurrence, i.e. the decrease below the permissible level of the safety coefficient, and the time period of development, so as to maintain the safety status of the massif.A method for determining the cost of maintaining the necessary stability or reliability coefficient value at a time when their calculated values are less than the respective permissible values is shown. …”
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Selection of appropriate multispectral camera exposure settings and radiometric calibration methods for applications in phenotyping and precision agriculture by Vaishali Swaminathan, J. Alex Thomasson, Robert G. Hardin, Nithya Rajan, Rahul Raman

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A method for measuring intraocular pressure using artificial intelligence technology and fixed-force applanation tonometry by D. A. Dorofeev, A. A. Antonov, D. Yu. Vasilenko, A. V. Gorobets, K. A. Efimova, E. V. Kanafin, E. V. Karlova, E. V. Kirilik, I. V. Kozlova, E. R. Orlova, A. Z. Tsyganov

“…To estimate the accuracy of IOP measurement using artificial intelligence (AI) technologies and applanation tonometry with fixed strength. Material and methods. 290 patients (576 eyes) underwent applanation tonometry according to Maklakov with tonometer weights of 5, 10, and 15 g using a modified elastotonometry technique followed by an analysis of impression quality and diameter measurements by three independent ophthalmologist experts. …”
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Study on Semi-Rigid Joint Performance and Stability Bearing Capacity of Disc-Type Steel Pipe Support by Fankui Zeng, Guoxin Zou, Meng Ji, Jianhua Zhang

“…Numerical simulation and analytical correction method were employed to determine the effective length correction coefficient <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi mathvariant="sans-serif">μ</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></semantics></math></inline-formula> under various erection parameters while accounting for joint semi-rigidity. …”
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Calculation Method of Shale Oil Fluid Component Content Based on Nuclear Magnetic Resonance T2 Distribution by LIU Jilong, XIE Ranhong, WEI Hongyuan, XU Chenyu, JIN Guowen, ZHENG Di, WANG Shaoxiang

“…Shale oil reservoirs, characterized by the complex occurrence state of fluid and complex mineral compositions, are difficult to accurately determine the fluid component content. Therefore, a method to determine the fluid component content of shale oil combining with continuous wavelet transform (CWT) and Gaussian distribution function is proposed in this paper. …”
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A Novel Method of Self-Healing Concrete to Improve Durability and Extend the Service Life of Civil Infrastructure by Yan Xue, Weiliang Gao, Yanming Zhao

“…Finally, the Pareto frontier solution set is processed using the ideal point method selection approach to determine the optimal concrete mix ratio scheme. …”
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Application of the Modified Method of ant Colonies to Search for Rational Assignment of Employees to Tasks Using Fuzzy Sets by V. A. Sudakov, Yu. P. Titov

“…The problem of “cycling” of the ant colony method, caused by the passage of agents along the same routes, is determined.Conclusion. …”
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A Data Resource Trading Price Prediction Method Based on Improved LightGBM Ensemble Model by Wan Nie, Bingliang Shen, Desheng Li

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Solvent extraction of europium(III) from technogenic solutions with the use of surfactants by N. V. Dzhevaga, O. L. Lobacheva

“…Infrared spectroscopy (Nicolet 6700 spectrometer) was used to determine the type of salts extracted into the organic phase. …”
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