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Articles 7621 - 7650 of 291657

Full-Text Articles in Physical Sciences and Mathematics

Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere Dec 2025

Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere

Turkish Journal of Chemistry

Gold is abundant in nature, however, precise and reliable analytical methods for its detection are required stemming from its increasing prevalence in environmental, biological, and industrial systems, as well as the growing interest in understanding its function in living organisms and its effects on human health. This study investigates the use of biogenically synthesized silver nanoparticles (AgNPs) for the preconcentration and determination of gold ions prior to determination by UV-Vis spectrophotometry. AgNPs were synthesized by reducing silver nitrate through the use of an apricot kernel extract as both reducer and stabilizer agent. The colloidal yellowish AgNPs interacted with gold ions, …

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Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee Dec 2025

Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee

Turkish Journal of Chemistry

Paclitaxel (Pac) is an important anticancer bioactive compound, and the availability of an accurate and robust analytical method for its quantification is of utmost importance. In this investigation, a novel, direct, and reliable spectrophotometric method has been proposed for the estimation of Pac via a complex formation reaction with osmium (Os). The method was based on the reaction of Pac with Os tetroxide, which produced a yellowish-brown complex. The resulting complex is soluble in water and displays a maximum absorption peak at 482 nm. The reaction conditions, including reactant concentration, pH, temperature, and reaction time, were optimized to obtain the …

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Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal Dec 2025

Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal

Turkish Journal of Chemistry

This study used single-crystal X-ray diffraction, elemental analysis, infrared (IR) spectroscopy, theoretical nuclear magnetic resonance (NMR), and theoretical ultraviolet spectroscopy to characterize 3 newly synthesized crystalline compounds. Additionally, the nonlinear optical, highest occupied molecular orbital energies, lowest occupied molecular orbital energies, band gap, molecular electrostatic potential, and thermodynamic parameters of the 3 crystalline compounds were examined. The strong correlation between experimental IR spectra and theoretical NMR chemical shifts confirmed the accuracy of computational predictions. The molecular formulas of the 3 newly synthesized crystalline compounds, each containing different ligand molecules, were: C8H14O4·2(C6H4N2), C5H7N2·NCS, and Ni(CN)4·2(C5H7N2)·2(H2O) for compounds 1, 2, and 3, …

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Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy Dec 2025

Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy

Turkish Journal of Chemistry

Novel coumarin–triazole–coumarin dyads were synthesized and characterized, and their α-glycosidase inhibitory activities were evaluated spectrophotometrically. Compound 4e exhibited the most pronounced inhibitory effect, with an IC50 value of 38.98 ± 0.77 μM. The IC50 values for 4d and 4a were 93.55 ± 1.70 μM and 95.04 ± 3.55 μM, respectively. The Lineweaver–Burk plot showed that 4e inhibited α-glycosidase in a mixed type. In addition, the Ki value obtained from the Dixon plot was 19.95 ± 0.15 μM for α-glycosidase.

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Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz Dec 2025

Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz

Turkish Journal of Chemistry

This study investigates the extraction behavior of Y³⁺ ions using a Multi-Dropped Liquid Membrane (MDLM) system that employs di(2-ethylhexyl) phosphoric acid (D₂EHPA) as the carrier ligand. The focus is on the system’s ability to transport ions between aqueous phases selectively. The extracted complex was analyzed spectrophotometrically via ultraviolet–visible (UV–Vis) measurements after complexation with 0.05% Arsenazo III. The aim of this study was to determine the influence of the optimum D₂EHPA carrier concentration, together with the pH and temperature conditions of the donor and acceptor phases, on the system’s extraction performance. Accordingly, a series of extraction experiments was performed at different …

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Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay Dec 2025

Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay

Turkish Journal of Chemistry

The direct synthesis of boron nitride nanotubes (BNNTs) via chemical vapor deposition (CVD) in high-temperature furnaces remains highly challenging due to difficulties in optimizing key experimental parameters such as synthesis temperature and catalyst composition. These challenges often result in uncontrolled growth behavior, adversely affecting the quality and yield of the BNNTs. In this study, colemanite was effectively utilized as a boron source for the high-yield synthesis of directionally aligned BNNTs. The synthesis was carried out using a CVD method that used a dual-catalyst system comprising Fe2O3 and MgO in conjunction with a silicon carbide template under high-temperature conditions. The resulting …

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Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat Dec 2025

Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat

Turkish Journal of Chemistry

This study highlights the potential of organometallic carbonyl complexes as selective markers for biomolecules, enabling sensitive infrared (IR) detection. The regio- and stereoselective coupling of N-acetylhistamine, a histidine analogue, with the precursor complex 1 [Fe(CO)₃(1,4-η⁵-N-pyridiniocyclohexa-1,3-diene)] BF₄ affords the labeled complex 3 [Fe(CO)₃(1,4-η⁵-N-acetylhistaminocyclohexa-1,3-diene)]. X-ray diffraction (XRD) confirms the exo stereochemistry and reveals a rigid, well-defined architecture. IR and 1H nuclear magnetic resonance spectroscopic studies combined with IR-monitored acid–base titration demonstrate the complex’s stability in aqueous media between pH 5 and 8, alongside a modest increase in basicity relative to the free ligand. These findings establish the Fe(CO)₃ moiety as a robust …

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Investigating Surface-Borehole Transient Electromagnetic Responses From Veined Orebodies Considering Induced Polarization Effects, Li Jianhui, Wang Yao, Wang Wenchuang, Xie Shaojian, Zhu Siwei Dec 2025

Investigating Surface-Borehole Transient Electromagnetic Responses From Veined Orebodies Considering Induced Polarization Effects, Li Jianhui, Wang Yao, Wang Wenchuang, Xie Shaojian, Zhu Siwei

Coal Geology & Exploration

Objective The observational data derived using the surface-borehole transient electromagnetic (TEM) method tend to feature complex curve morphologies, a problem posing significant challenges to data processing and interpretation. This study aims to ascertain the mechanisms behind the generation of such complex responses using forward modeling.Methods Using the vector finite element-based spectral method and the Cole-Cole model, this study developed a 3D forward modeling technique incorporating the induced polarization (IP) effect. By constructing a typical theoretical model of low-resistivity veined orebodies, it systematically analyzed the electromotive force (EMF) responses excited by transmitter loops at different orientations. Results and Conclusions The …

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Coal Body Structure Identification Method Based On Bayesian-Optimized Cnn-Bilstm-Attention, Bian Huiyuan, Ji Jiajun, Duan Chaowei, Zhou Jun, Li Kun, Ma Yuhan Dec 2025

Coal Body Structure Identification Method Based On Bayesian-Optimized Cnn-Bilstm-Attention, Bian Huiyuan, Ji Jiajun, Duan Chaowei, Zhou Jun, Li Kun, Ma Yuhan

Coal Geology & Exploration

Background Coal-bearing basins contain primary and tectonically deformed coals due to multistage tectonic deformations. However, the gas-bearing properties of coal seams differ significantly due to varying pore and fracture densities, permeability, and mechanical properties. This makes coal structure assessment critical to coalbed methane (CBM) exploration and production. Objective and Method To enhance the accuracy and intelligence of coal structure identification, this study constructed a CNN-BiLSTM-Attention hybrid model that integrated a Bayesian optimization strategy. This model allowed for efficient fusion and representation of multi-scale log data by combining the local feature extraction capability of the convolutional neural network (CNN), the temporal …

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Self-Adaptive Inverse Wavefield Transform And Derived Pseudo-Wavefield Characteristics Under Roadway-Borehole Observation Of Transient Electromagnetic Data, Fan Kerui, Guo Jianlei, Wang Ruoyu, Zhuang Ming, Fan Fangze, Xu Sheng, Zhao Wentao Dec 2025

Self-Adaptive Inverse Wavefield Transform And Derived Pseudo-Wavefield Characteristics Under Roadway-Borehole Observation Of Transient Electromagnetic Data, Fan Kerui, Guo Jianlei, Wang Ruoyu, Zhuang Ming, Fan Fangze, Xu Sheng, Zhao Wentao

Coal Geology & Exploration

Objective To address the challenge of detecting aquifers outside the roadway excavation contour, this study combined the close-range detection via roadway-borehole transient electromagnetic (TEM) method with the wavefield transform. This will help simultaneously receive detection signals in front of the mining face and outside the roadway excavation contour while also highlighting the boundary information of aquifers. Moreover, to obtain a pseudo-wavefield featuring both reasonable kinematic characteristics and high sensitivity to changes in the electrical structures of strata, this study proposed a self-adaptive algorithm of inverse wavefield transform, thereby improving the accuracy and efficiency of the inverse wavefield transform of roadway-borehole …

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Performance And Migration Path Tracing Of Magnetic Grouts For Fractured Rock Masses, Shang Hongbo, Wang Hao, Wang Xiaodong, Qiao Wei, Wang Tiantian, Sun Junqing, Sun Jie Dec 2025

Performance And Migration Path Tracing Of Magnetic Grouts For Fractured Rock Masses, Shang Hongbo, Wang Hao, Wang Xiaodong, Qiao Wei, Wang Tiantian, Sun Junqing, Sun Jie

Coal Geology & Exploration

Objective For coal mining areas in the middle reaches of the Yellow River basin, sealing mining-induced fractures via grouting serves as an effective approach to preventing water inrushes from coal seam roofs while also protecting groundwater resources. However, accurately identifying the migration paths of grouts remains a bottleneck for the further application of grouting modification technology to fractured rock masses. Methods This study investigated a coal mine threatened by both water inrushes from the coal seam roof and a short supply of water resources within the Jurassic coalfield in the middle reaches of the Yellow River basin, focusing on the …

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An Automated Attitude Control Method For The Rotary Steerable System And Its Validation Through Hardware-In-The-Loop Simulation, Zhang Nan, Ren Bai’An, Li Fei, Liu Ziqi, Lyu Fangxing Dec 2025

An Automated Attitude Control Method For The Rotary Steerable System And Its Validation Through Hardware-In-The-Loop Simulation, Zhang Nan, Ren Bai’An, Li Fei, Liu Ziqi, Lyu Fangxing

Coal Geology & Exploration

Objective The traditional manual control mode of a rotary steerable system (RSS) faces challenges, including response delay and low control efficiency. To address these challenges, this study proposed a closed-loop automated attitude control method for the RSS and verified its effectiveness through hardware-in-loop (HIL) simulation. Methods This study focuses on the drilling process of a point-the-bit RSS. In the case of deviations between measured and target attitudes, the control parameters were calculated based on the deviation signals using a closed-loop controller, driving the RSS actuator to conduct trajectory correction. Afterward, the actual attitude was yielded and then entered the input …

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Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin Dec 2025

Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin

Coal Geology & Exploration

Objective The pore structures of clastics play a crucial role in assessing the potential of saline aquifers for geologic CO2 sequestration. Current studies on pore structures during CO2 sequestration focus primarily on artificial cores. However, compared to artificial cores, natural cores feature more complex pore size distributions and stronger heterogeneity. Methods This study examined a natural core from deep reservoirs in the Ordos Basin and two artificial cores with different porosities through CO2-water displacement experiments under water-saturated conditions. Using a nuclear magnetic resonance (NMR) analysis and imaging system for multiphase fluid displacement, this study analyzed the …

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Impacts Of Anti-Rock Burst Multistage Hydraulic Fracturing Using Horizontal Wells On Mining Roadways And Fracture Control Techniques: A Case Study Of Mining Facein The Zhaoxian Coal Mine, Shaanxi Province, Liu Xiugang, Jiang Zaibing, Yang Juan, Liu Mingjun, Pang Tao, Wu Weixing, Tu Xiaolong, Mo Haitao, Guo Xiaolong, Du Xinfeng Dec 2025

Impacts Of Anti-Rock Burst Multistage Hydraulic Fracturing Using Horizontal Wells On Mining Roadways And Fracture Control Techniques: A Case Study Of Mining Facein The Zhaoxian Coal Mine, Shaanxi Province, Liu Xiugang, Jiang Zaibing, Yang Juan, Liu Mingjun, Pang Tao, Wu Weixing, Tu Xiaolong, Mo Haitao, Guo Xiaolong, Du Xinfeng

Coal Geology & Exploration

Objective Surface multistage hydraulic fracturing of hard roofs using horizontal wells serves as an important technique for rock burst control in mines. However, fracturing technique under improper control might pose adverse impacts on excavated mining roadways underground, causing roadway deformation, mesh failure with block falling, and the flow of fracturing fluids into the roadways. Methods This study investigated certain mining face of the Zhaoxian Coal Mine in the Yonglong mining area, Shaanxi Province. Targeting different characteristics and phenomena of roadways following hydraulic fracturing, this study analyzed the reasons why fracturing fluids flowed into roadways during hydraulic fracturing using theoretical analysis, …

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Lithofacies Paleogeography Of The Ordovician Kelimoli-Lashizhong Formations Along The Western Margin Of The Ordos Basin, Wang Weibin, Ma Zhanrong, Hu Aiping, Zhang Qian, Li Wenhou, Chen Qiang, Ma Yao, Wang Yanbo Dec 2025

Lithofacies Paleogeography Of The Ordovician Kelimoli-Lashizhong Formations Along The Western Margin Of The Ordos Basin, Wang Weibin, Ma Zhanrong, Hu Aiping, Zhang Qian, Li Wenhou, Chen Qiang, Ma Yao, Wang Yanbo

Coal Geology & Exploration

Objective The period during the deposition of the Middle-Late Ordovician Kelimoli-Lashizhong formations witnessed a key transition of the tectonic framework along the western margin of the Ordos Basin. Investigating the lithofacies paleogeography of these formations can reveal the tectono-sedimentary responses during this period, thereby providing a basis for the resource potential prediction, exploration, and exploitation of natural gas in the study area. Methods Using field section observations, core observations, and log interpretations, as well as previous research results, this study comprehensively analyzed the Middle-Late Ordovician strata in the Ordos Basin from the perspectives of stratigraphy, sedimentary system division, and sedimentary …

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Intelligent Lithology Identification While Drilling Using Bilstm Integrating Attention Mechanism, Wang Xi, Peng Fengjia, Li Siyang, Guo Xiao, Zhang Feifei, Ran Xiaofeng, Zhang Cong Dec 2025

Intelligent Lithology Identification While Drilling Using Bilstm Integrating Attention Mechanism, Wang Xi, Peng Fengjia, Li Siyang, Guo Xiao, Zhang Feifei, Ran Xiaofeng, Zhang Cong

Coal Geology & Exploration

Objective Vibration signals while drilling reflect the physical properties and microstructural characteristics of rocks, providing a valuable basis for real-time lithology identification. However, existing models suffer from limited accuracy and robustness due to the low dimensionality of signal features and the class imbalance induced by variations in the rock layer thickness. Methods To overcome these limitations, this study proposed a novel lithology identification method based on a bidirectional long short-term memory (BiLSTM) network that integrates attention mechanism (also referred to as the BiLSTM-Attention). This approach incorporates automated feature extraction and class weight adjustment strategies to enhance both the classification performance …

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Uniqueness And Prospects Of Co2 Sequestration In Basalts, Hu Chenlin, Sang Shuxun, Li Xin, Rui Zhenhua, Liu Shiqi, Wang Ziqiang, Xie An, Yu Huan Dec 2025

Uniqueness And Prospects Of Co2 Sequestration In Basalts, Hu Chenlin, Sang Shuxun, Li Xin, Rui Zhenhua, Liu Shiqi, Wang Ziqiang, Xie An, Yu Huan

Coal Geology & Exploration

Objective and Method CO2 sequestration in basalts offers advantages such as permanent carbonation and elevated safety. Based on literature review and case studies, this study compared the CO2 sequestration performance of basalts, clastic rocks, and carbonate rocks. Accordingly, the pros and cons of technologies for CO2 sequestration in these rocks were determined, and the dominant mechanisms underlying the CO2 sequestration were identified. By revealing the characteristics of CO2 sequestration in the three rock types based on representative projects and tests, this study conducted a comparative analysis of the mechanisms, conditions, technologies, potential, and siting for …

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New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş Dec 2025

New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş

Turkish Journal of Chemistry

A series of novel bis-piperazine derivatives (2a–2f) were synthesized and structurally characterized via Fourier transform-infrared and nuclear magnetic resonance spectroscopic techniques. Their gamma-ray shielding efficiencies were investigated through simulations on the Monte Carlo-based Geant4-GATE platform, and the results were benchmarked against data obtained from the XCOM and Phy-X software. A simulation model incorporating an NaI scintillation detector and a point gamma source was developed. Key shielding parameters, including mass attenuation coefficient, linear attenuation coefficient, half-value layer, and mean free path (MFP), were evaluated at gamma energies of 80, 120, 662, 1173, and 1332 keV. Additionally, the energy absorption buildup factor …

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Structural Categorization And Identification Of Electrostatic Interactions In Two Proposed Human Serum Albumin Dimerization Patterns And Dipyridamole Interaction, Haluk Çeti̇nok, Veyi̇s Karakoç, Erol Erçağ, Yusuf Meli̇h Şekerer, Hasan Demi̇rci̇ Dec 2025

Structural Categorization And Identification Of Electrostatic Interactions In Two Proposed Human Serum Albumin Dimerization Patterns And Dipyridamole Interaction, Haluk Çeti̇nok, Veyi̇s Karakoç, Erol Erçağ, Yusuf Meli̇h Şekerer, Hasan Demi̇rci̇

Turkish Journal of Chemistry

Human serum albumin (HSA) is a ubiquitous, multifunctional protein responsible for the systemic distribution of both endogenous metabolites and exogenous pharmaceuticals. Its inherent properties, particularly its ability to seep into tissues and its multiple ligand-binding sites, have rendered HSA an attractive vehicle for nanoparticle-based drug delivery systems, particularly for cancer targeting. In this study, we present high-resolution crystallographic data revealing two distinct dimerization patterns of HSA (Protein Data Bank [PDB] ID: 9V61) obtained under high-concentration crystallization conditions, along with results from dipyridamole docking. Both dimer types demonstrate extensive interface areas and a significant number of electrostatic interactions. Comparative analysis with …

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Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh Dec 2025

Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh

Turkish Journal of Chemistry

Hydrazone chemistry has become important and plays a key role in the development of organic compounds. Hydrazones can be useful pharmacophores for creating novel derivatives, owing to their broad range of activities. In this study, a series of N-((2-hydroxy-3-(2-(substitutedbenzylidene)hydrazine-1-carbonyl)naphthalen-1-yl)(3-nitro-phenyl/3,4-dimethoxyphenyl)methyl)acetamide derivatives were prepared, characterized by FTIR, 1H-NMR, 13C-NMR, and mass spectroscopy, and evaluated for their antimicrobial, antiinflammatory, and antioxidant activities along with in silico studies. The substituted derivatives were synthesized by the reaction of acetonitrile, chlorosulphonic acid, and substituted benzaldehyde with the hydrazones. The antimicrobial evaluation showed that compound 3i had more antimicrobial potential than the other tested molecules. Compound 3j …

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Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman Dec 2025

Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman

Turkish Journal of Chemistry

In this work, electrochemical biosensors utilizing tyrosinase (Tyr) for the detection of the nonselective beta-adrenergic agonist isoproterenol (ISO) are presented. Three different configurations for immobilizing Tyr on a graphite electrode (GE) are compared: (1) GE modified with poly(diallyldimethylammonium chloride) (PDADMAC), PDADMAC/Tyr/GE; (2) PDADMAC combined with iridium nanoparticles (IrNPs) in a stepwise preparation, resulting in PDADMAC/IrNPs/Tyr/GE; and (3) a composite of PDADMAC and IrNPs mixed with Tyr at a 1:1 (v:v), forming PDADMAC/(IrNPs-Tyr)/GE. Surface morphology was characterized using scanning electron microscopy (SEM). Cyclic voltammetry (CV) and amperometry were applied to characterize the biosensor’s performance. Within the linear range of 5 μM …

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A Simulation Study On A Dual-Borehole Dc Resistivity System For Advance Detection Under Varying Angles, Zhou Guanqun, Xu Shaotian, Zhang Weixin, Wang Yafei, Wu Xiaoping, Hu Xiongwu, Chen Xinghai, Cao Yu Dec 2025

A Simulation Study On A Dual-Borehole Dc Resistivity System For Advance Detection Under Varying Angles, Zhou Guanqun, Xu Shaotian, Zhang Weixin, Wang Yafei, Wu Xiaoping, Hu Xiongwu, Chen Xinghai, Cao Yu

Coal Geology & Exploration

Significance Mine direct current (DC) methods, an efficient geophysical exploration technique, can be used to identify and delineate underground electrical resistivity anomalies, serving as a critical means for the advance detection of water-bearing or hydraulically conductive structures ahead of the mining face. Methods By combining the water exploration and discharge boreholes commonly used in coal mining and making reference to the observation system of the ground-based cross-borehole DC resistivity CT method, this study devised a dual-borehole DC resistivity observation system for advance detection. Through numerical simulation using the COMSOL software, this study constructed a homogeneous full-space model, in which a …

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Structural Evolution And Spontaneous Combustion And Activation Mechanisms Of Coals Treated Under Inert Atmospheres In A Coal Mine Goaf, Zhang Leilin, Li Wanting, Wen Chenchen Dec 2025

Structural Evolution And Spontaneous Combustion And Activation Mechanisms Of Coals Treated Under Inert Atmospheres In A Coal Mine Goaf, Zhang Leilin, Li Wanting, Wen Chenchen

Coal Geology & Exploration

Objective When used for the treatment of fire zones in deep coal mine goafs, low-oxygen and inertization techniques suffer from a scientifically blind spot, i.e., the fire prevention and control bottleneck caused by a high susceptibility to re-ignition of coals after being treated with high-temperature, low-oxygen (or inert) gas. To overcome this limitation, this study aims to systematically determine the mechanisms by which the evolution of the physical and chemical structures of coals after heat treatment under different atmospheres influences their spontaneous combustion and activation behavior. The purpose is to provide theoretical support for the treatment and safe opening of …

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A Method For Interpretating Acoustic Reflection Imaging Logging Data Of Fractured-Vuggy Reservoirs Based On Their Theoretical Response Characteristics, Huang Ruokun, Jiang Kai, Wu Xingneng, Ma Kunyu, Su Yuanda, Wang Bing, Chen Xu Dec 2025

A Method For Interpretating Acoustic Reflection Imaging Logging Data Of Fractured-Vuggy Reservoirs Based On Their Theoretical Response Characteristics, Huang Ruokun, Jiang Kai, Wu Xingneng, Ma Kunyu, Su Yuanda, Wang Bing, Chen Xu

Coal Geology & Exploration

Objective During the exploration and development of fractured-vuggy carbonate reservoirs, acoustic reflection imaging logging technology enables the detection of fractured-vuggy bodies around wells. However, this technology suffers from unclear response characteristics and a strong multiplicity of solutions. Focusing on the Tarim Oilfield, this study aims to establish a tailored interpretation method by integrating geological and geophysical characteristics. The purpose is to enhance the identification accuracy and reliability of fractured-vuggy bodies in these reservoirs. Methods Based on the distribution characteristics of fractured-vuggy carbonate reservoirs in the Tarim Oilfield, this study established the numerical simulation models of three typical fractured-vuggy bodies: inter-breccia …

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Numerical Simulations Of Dynamic Rock Damage Under Laser-Induced Shock Waves, Xu Yuelin, Qin Enwei, Li Wei, Wang Ying Dec 2025

Numerical Simulations Of Dynamic Rock Damage Under Laser-Induced Shock Waves, Xu Yuelin, Qin Enwei, Li Wei, Wang Ying

Coal Geology & Exploration

Objective Traditional laser thermal rock breaking technologies suffer from high energy consumption and a limited damage depth. To overcome these challenges, this study proposed a novel mechanical rock breaking method based on high-pressure plasma shock waves induced by short pulsed lasers, aiming to transform a thermodynamics-dominated rock breaking mechanism into a dynamics-dominated mechanism. Methods and Results Under the Abaqus/Explicit explicit dynamics framework, this study constructed a finite element model to simulate the interactions between nanosecond laser-induced shock waves and rocks. The accurate loading of shock wave pressure in the spatial and temporal domains was achieved using the VDLOAD user subroutine. …

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A Novel Model For Calculating In Situ Stress Within Deep Coal Seams Considering Microstructural Characteristics And Its Application, Zhao Haifeng, Shi Hongwei, Xie Fei, Wang Chengwang, Wang Zongfei, Chen Gaojie Dec 2025

A Novel Model For Calculating In Situ Stress Within Deep Coal Seams Considering Microstructural Characteristics And Its Application, Zhao Haifeng, Shi Hongwei, Xie Fei, Wang Chengwang, Wang Zongfei, Chen Gaojie

Coal Geology & Exploration

Objective Research on in situ stress serves as a bridge between geological and engineering analyses. Accurate insights into in situ stress regimes are crucial for ensuring engineering efficiency and development benefits. However, microstructures are well developed in deep coal seams, for which no effective model is currently available for calculating in situ stress. Methods and Results By classifying structures into macrostructures and microstructures, this study established a novel model for calculating in situ stress in deep coal seams while considering microstructural characteristics. In the novel model, the horizontal in situ stress was decomposed into three components: the horizontal components induced …

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Technique For Water-Preserved Coal Mining Based On Zonal Height Limits Along Mining Face And Mechanisms Behind Overburden Failure, Sun Xueyang, Cao Hongyi, Li Peng, Han Dehao, Luo Qiyao, Liu Kuan, Li Jihong, Yin Xu Dec 2025

Technique For Water-Preserved Coal Mining Based On Zonal Height Limits Along Mining Face And Mechanisms Behind Overburden Failure, Sun Xueyang, Cao Hongyi, Li Peng, Han Dehao, Luo Qiyao, Liu Kuan, Li Jihong, Yin Xu

Coal Geology & Exploration

Objective The exploitation of shallow coal seams under water bodies faces a contradiction between water resource preservation and overburden disturbance. In this case, achieving safe mining while preventing water-conducting fracture zones from affecting key aquifers and exploring techniques that place equal emphasis on water preservation and efficient resource recovery have emerged as popular research topics. Methods An integrated aquifer-overburden-coal seam model was constructed using 3D geological visualization technology. This model, combined with the principles for the setting up of waterproof coal pillars, enabled accurate delineation of zones with water inrush risks. Accordingly, a technical scheme for mining based on zonal …

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Simulation Of Groundwater Flow Field Evolution And Water Inrush Risks Under The Deep-Well Reinjection Of High-Tds Mine Water, Liu Qi, Sun Yajun, Fan Jianguo, Tan Xianfeng, Xiao Shengxin, Yang Chuanwei, Chen Weiyang, Chen Ge Dec 2025

Simulation Of Groundwater Flow Field Evolution And Water Inrush Risks Under The Deep-Well Reinjection Of High-Tds Mine Water, Liu Qi, Sun Yajun, Fan Jianguo, Tan Xianfeng, Xiao Shengxin, Yang Chuanwei, Chen Weiyang, Chen Ge

Coal Geology & Exploration

Objective The deep-well reinjection of mine water results in a regional groundwater level rise to varying degrees, possibly inducing hydrogeological hazards such as floor water inrushes or water inrushes along faults. In this context, determining the evolutionary pattern of the groundwater flow field under long-term mine water reinjection and conducting reinjection safety assessments play a critical role in ensuring both the safety of mine water reinjection and water conservation-based coal mining.Methods This study examined the reinjection of mine water in a coal mine within the Juye coalfield, North China. Based on the geological conditions for mine water reinjection in …

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An Experimental Study On The Deterioration Characteristics Of Sandstone Masses With Rock Bridges Under Cyclic Freezing And Thawing, Zhang Huimei, Li Zengle, Chen Shiguan, Yuan Chao, Zheng Shihang Dec 2025

An Experimental Study On The Deterioration Characteristics Of Sandstone Masses With Rock Bridges Under Cyclic Freezing And Thawing, Zhang Huimei, Li Zengle, Chen Shiguan, Yuan Chao, Zheng Shihang

Coal Geology & Exploration

Objective To determine the deformation and failure mechanisms of fractured rock masses with rock bridges in alpine regions, this study conducted mechanical property tests on rock samples with varying lengths of rock bridges subjected to cyclic freezing and thawing. Methods Through experiments, this study summarized the characteristics of the static strength deterioration of rock masses under the combined effects of different numbers of freezing and thawing cycles and varying rock bridge lengths. By combining acoustic emission signal monitoring and scanning electron microscopy, this study thoroughly explored both the evolutionary characteristics of fractures and rock rupture modes. Accordingly, it revealed the …

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Table Of Contents, The Editors Dec 2025

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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