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Articles 14041 - 14070 of 294494

Full-Text Articles in Physical Sciences and Mathematics

Geochemical Nature Of The Geothermal Water From Lanzhou Basin: Implications For The Genesis Of Shallow Helium-Bearing Fluids, Tang Jianzhou, Wang Shuangming, Zhang Zhicheng, Li Ke, Li Changpeng Jun 2025

Geochemical Nature Of The Geothermal Water From Lanzhou Basin: Implications For The Genesis Of Shallow Helium-Bearing Fluids, Tang Jianzhou, Wang Shuangming, Zhang Zhicheng, Li Ke, Li Changpeng

Coal Geology & Exploration

Objective and Methods Investigations on the geochemical nature of geothermal water are vital to the comprehension of the origin of helium-rich fluids in shallow basins. To address this issue, this paper reports the results of the chemical analysis, H-O isotopes and 14C ages from geothermal water and soluble gas components from the well BY-1 in Lanzhou Basin, northeastern margin of Qinghai Tibet Plateau. Chemical analysis of geothermal water samples reveals that the chemical type of geothermal water is NaCl. The show δD value of –78‰, high δ18O value (–8.7‰), low 3H value (<0.4TU), and old 14C …


Impacts Of Metakaolin And Fly Ash On The Performance Of Cement-Based Grouting Materials In Anchoring Engineering, Cheng Zhiyuan, Yang Junpeng, Xue Wei, Wei Daidong, Wang Yimin Jun 2025

Impacts Of Metakaolin And Fly Ash On The Performance Of Cement-Based Grouting Materials In Anchoring Engineering, Cheng Zhiyuan, Yang Junpeng, Xue Wei, Wei Daidong, Wang Yimin

Coal Geology & Exploration

Objective The filling of grouting materials plays a significant role in ensuring the performance of anchoring structures. This study aims to further enhance the fluidity of grouting materials, reduce their dry shrinkage in the curing process, and ensure complete filling. This will help improve the bonding property between the anchoring body and the rock and soil mass to be reinforced. Methods Using cement as the primary material, as well as fly ash and metakaolin as admixtures, this study designed and prepared 20 groups of binary and ternary mixtures and one control group. Through tests of the fluidity, bleeding ratios, and …


Diffusion Mechanisms Of Coal-Measure Helium And Their Implications For Helium Accumulation: A Case Study Of The Taiyuan Formation, Northern Qinshui Basin, China, Ma Yong, Xin Zhiyuan, Chen Jianfa, Li Yuhong, Zhang Xiutao, Jiang Haojie, Chen Zeya Jun 2025

Diffusion Mechanisms Of Coal-Measure Helium And Their Implications For Helium Accumulation: A Case Study Of The Taiyuan Formation, Northern Qinshui Basin, China, Ma Yong, Xin Zhiyuan, Chen Jianfa, Li Yuhong, Zhang Xiutao, Jiang Haojie, Chen Zeya

Coal Geology & Exploration

Objective The global helium-rich gas reservoirs are dominated by conventional natural gas reservoirs. In recent years, helium-bearing natural gas has been discovered in the Carboniferous-Permian coal measures in the Ordos Basin and surrounding regions, revealing the resource potential of coal-measure helium. However, there is almost a total lack of studies on mechanisms underlying the diffusion and migration of coal-measure helium. This severely restricts further research on the accumulation patterns of coal-measure helium.Methods This study investigated a coal seam in the Taiyuan Formation in the northern Qinshui Basin and mudstones in the coal seam roof. Using physical diffusion experiments on …


Colloidal Hot-Injection Synthesis Of Cubse2 Nanocrystals: Tetragonal Chalcogenide Templates For Superionic Lithiation Pathways, Yunhao Xu, Niket Powar, Kelly Zervos, Isabella Campbell, Simran Choudhary, Layan Al-Khaled, Progna Banerjee Jun 2025

Colloidal Hot-Injection Synthesis Of Cubse2 Nanocrystals: Tetragonal Chalcogenide Templates For Superionic Lithiation Pathways, Yunhao Xu, Niket Powar, Kelly Zervos, Isabella Campbell, Simran Choudhary, Layan Al-Khaled, Progna Banerjee

Chemistry: Faculty Publications and Other Works

Copper boron selenides represent a previously unexplored class of materials with tetragonal structural symmetries and bonding chemistries potentially relevant to lithium-ion conduction. In this work, the first colloidal synthesis of nanocrystalline copper boron selenides is reported, enabling access to nanocrystals with reaction times shown as the synthetic knob to control composition and morphology. Copper boron selenide nanocrystals are synthetically designed as precursors for lithiation reactions aimed at probing structural evolution and ionic mobility pathways toward superionic conductors applicable as solid electrolytes in lithium-ion batteries. Postsynthetic lithiation studies under ambient conditions reveal a series of phase transformations and morphological changes, which …


Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole, Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo Jun 2025

Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole, Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo

Turkish Journal of Physics

This paper investigates the geodesics of the Schwarzschild black hole modified with the quintessence field and modeled as a barotropic fluid with a constant equation of state derived in Boyer Lindquist coordinates with natural units G = c = 1. Hamilton–Jacobi formalization is applied to investigate the geodesics in both static and nonstatic black hole spacetime. It specifically examines the formation of bound orbits of test particles around the black hole, highlighting that these orbits result from the interplay between the gravitational pull of the black hole and a repulsive force associated with quintessence. The thermodynamic properties of a black …


Selecting An Internal Carbon Price For Academic Institutions, Alexander R. Barron, Dimitra Prassa Jun 2025

Selecting An Internal Carbon Price For Academic Institutions, Alexander R. Barron, Dimitra Prassa

Environmental Science and Policy: Faculty Publications

Many businesses have adopted internal carbon prices (ICPs) to help drive smarter business decisions, innovation, and emissions reductions. The objective of this white paper is to provide a framework that institutions, particularly those in higher education, can use as they think about selecting a price in the context of their own goals for an ICP.

Second Nature’s recent 2025 Carbon Markets and Offsets guidance recommends that: “colleges and universities develop a climate action strategy that includes some type of internal carbon pricing, either as a mechanism to inform climate-positive decision-making or as a mechanism for generating revenue estimates for decarbonization …


Homework, Households, And Hurdles: The Unexpected Drivers Of Student Graduation Perceptions, Daniel Alhassan, Zahra Fatah, Priscilla Mansah Codjoe, Caroline Bena Kuno, Dorcas Ofori-Boateng Jun 2025

Homework, Households, And Hurdles: The Unexpected Drivers Of Student Graduation Perceptions, Daniel Alhassan, Zahra Fatah, Priscilla Mansah Codjoe, Caroline Bena Kuno, Dorcas Ofori-Boateng

Mathematics and Statistics Faculty Publications and Presentations

Students’ perceptions of their likelihood to graduate are important determinants of their academic engagement, yet these perceptions remain understudied. This study, which is based on the 2021 Monitoring the Future survey of 8th- and 10th-grade students in the United States, uses machine learning algorithms to identify the most important factors that influence these perceptions. Among the tested models, random forest provided the best classification performance. Using permutation-based feature importance, we identified frequent participation in schoolwork, maternal education, paternal education, and homework completion as the most important predictors of students’ graduation perceptions. These results highlight the importance of targeted and well-coordinated …


Kolmogorov–Smirnov-Based Edge Centrality Measure For Metric Graphs, Christina Durón, H. Kravitz, Moysey Brio Jun 2025

Kolmogorov–Smirnov-Based Edge Centrality Measure For Metric Graphs, Christina Durón, H. Kravitz, Moysey Brio

Mathematics and Statistics Faculty Publications and Presentations

In this work, we introduce an edge centrality measure for the Helmholtz equation on metric graphs, a particular flow network, based on spectral edge energy density. This measure identifies influential edges whose removal significantly changes the energy flow on the network, as indicated by statistically significant p-values from the two-sample Kolmogorov–Smirnov test comparing edge energy densities in the original network to those with a single edge removed. We compare the proposed measure with eight vertex centrality measures applied to a line graph representation of each metric graph, as well as with two edge centrality measures applied directly to each …


Table Of Contents, The Editors Jun 2025

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Construction And Application Of A Tcn-Lstm-Svm-Based Time Series Prediction Model For Water Inflow In Coal Seam Roofs, Liu Xuan, Ji Yadong, Zhu Kaipeng, Zhao Chunhu, Li Kai, Li Chaofeng, Yuan Chenhan, Li Panpan, Yan Pengzhen Jun 2025

Construction And Application Of A Tcn-Lstm-Svm-Based Time Series Prediction Model For Water Inflow In Coal Seam Roofs, Liu Xuan, Ji Yadong, Zhu Kaipeng, Zhao Chunhu, Li Kai, Li Chaofeng, Yuan Chenhan, Li Panpan, Yan Pengzhen

Coal Geology & Exploration

Background The accurate prediction of mine water inflow plays a significant role in the prevention and control of water hazards and the safe and efficient production in coal mines. Methods To construct a prediction model of water inflow in mines under threat of water hazards from extremely thick sandstones aquifer in West China, this study investigated a typical mine (also referred to as the studied mine) severely affected by such water hazards in the Binchang mining area of Shaanxi Province. The correlation between the mining footage and water inflow of the mining face was selected as the characteristic variable for …


Technical Advances And Research Directions Of Borehole Geophysical Prospecting For Coal Mines, Cheng Jianyuan, Yan Yu, Li Yuteng, Wang Pan, Zhao Rui, Jiang Bici Jun 2025

Technical Advances And Research Directions Of Borehole Geophysical Prospecting For Coal Mines, Cheng Jianyuan, Yan Yu, Li Yuteng, Wang Pan, Zhao Rui, Jiang Bici

Coal Geology & Exploration

Background High-precision and long-distance exploration of geological conditions is required for coal extraction and disaster prevention in coal mines. However, traditional drilling and geophysical prospecting methods face technical bottlenecks such as insufficient exploration accuracy and limited exploration ranges. Borehole geophysical prospecting technology integrates the reliable and straightforward axial results of drilling with the high-resolution transverse results of geophysical prospecting, providing technical support for safe, efficient, and intelligent coal mining. Based on the construction spaces, this study categorizes borehole geophysical prospecting technology into four types: i.e., intra-borehole, inter-borehole, borehole-surface, and borehole-roadway. Furthermore, it presents the primary advances and applicable conditions of …


Implications Of Helium Accumulation Models In Helium-Rich Basins In China For The Enrichment And Exploration Of Helium In Coal Measures, Li Yunbo, Wang Chengtao, Song Dangyu, Shi Xiaowei, Wang Rongqi Jun 2025

Implications Of Helium Accumulation Models In Helium-Rich Basins In China For The Enrichment And Exploration Of Helium In Coal Measures, Li Yunbo, Wang Chengtao, Song Dangyu, Shi Xiaowei, Wang Rongqi

Coal Geology & Exploration

Background Helium is a strategic resource in serious short supply in China, and intensifying its exploration is crucial to national resource security. China enjoys abundant coal measure gas and significant potential for associated helium accumulation. However, relevant research remains in its infancy. Methods Based on a summary and analysis of helium generation, migration, and accumulation theories in natural gas reservoirs, this study systematically investigated the enrichment patterns of helium in coal measures and proposed exploration targets. Results and Conclusions The insights reveal that the helium resources in China exhibit a distribution pattern of zoning in both north-south and east-west directions. …


Mechanisms Underlying Differential Helium Enrichment In Shale Gas Of Varying Structural Styles In The Southeastern Sichuan Basin, Xin Zhiyuan, Chen Jianfa, Wang Jie, Ma Yong Jun 2025

Mechanisms Underlying Differential Helium Enrichment In Shale Gas Of Varying Structural Styles In The Southeastern Sichuan Basin, Xin Zhiyuan, Chen Jianfa, Wang Jie, Ma Yong

Coal Geology & Exploration

Objective Shale gas reservoirs hold considerable helium reserves despite relatively low helium abundance, establishing them as a critical replacement for helium production growth. The southeastern Sichuan Basin exhibits diverse structural styles with varying preservation conditions, leading to an unclear understanding of the distribution characteristics and enrichment patterns of helium in shale gas. Determining the mechanisms behind the differential helium enrichment in shale gas is significant for the effective utilization of helium in shale gas.Methods Focusing on the typical shale gas reservoirs of different structural styles in the southeastern Sichuan Basin, this study explored the mechanisms underlying differential helium accumulation …


Physical Simulation Experiments On Competitive Dissolution Of Helium In Helium-Containing To Helium-Rich Gas Reservoirs, Zou Yi, Luo Qingyong, Chen Jianfa, Zou Huayao, Du Tao, Liu Xiaoqiang, Cai Xinyong, Yu Chengming, Fang Zilong Jun 2025

Physical Simulation Experiments On Competitive Dissolution Of Helium In Helium-Containing To Helium-Rich Gas Reservoirs, Zou Yi, Luo Qingyong, Chen Jianfa, Zou Huayao, Du Tao, Liu Xiaoqiang, Cai Xinyong, Yu Chengming, Fang Zilong

Coal Geology & Exploration

Background and Purpose Helium is widely applied in high-tech and scientific research fields due to its unique physicochemical properties. Formation water plays a key role in helium migration and enrichment. Typically, in the form of dissolved gas, helium is transported in pores or fractures by formation water. When helium-rich fluids migrate to shallow natural gas reservoirs, helium will experience dissolution and desorption exchange with other gases. This process is affected by formation temperature, pressure, and water salinity, as well as the competitive dissolution between helium and other gases. However, there is a lack of studies on the mechanisms underlying the …


Dominant Factors Causing Helium Deficiency In Coal-Measure Natural Gas In The Kuqa Depression, Tarim Basin, Liu Jiarun, Liu Quanyou, Li Pengpeng, Gao Yu, Lü Jiahao Jun 2025

Dominant Factors Causing Helium Deficiency In Coal-Measure Natural Gas In The Kuqa Depression, Tarim Basin, Liu Jiarun, Liu Quanyou, Li Pengpeng, Gao Yu, Lü Jiahao

Coal Geology & Exploration

Background Helium is identified as a scarce strategic resource, having found widespread applications in high-tech fields such as high-end manufacturing, aerospace, and national defense due to its stable chemical properties and low boiling point. The Kuqa Depression in the Tarim Basin is a significant natural gas production base in China. Determining the distribution characteristics and controlling factors of helium in coal-measure natural gas in the Kuqa Depression holds great significance.Methods Using two helium resource assessment methods and geological data, this study explored the dominant factors causing helium deficiency in the coal-measure natural gas in the Kuqa Depression.Results and …


Resource Potential And Extraction Technique Design For Helium In Coal Measures, Wang Lei, Tang Maoyin Jun 2025

Resource Potential And Extraction Technique Design For Helium In Coal Measures, Wang Lei, Tang Maoyin

Coal Geology & Exploration

Back ground Helium is an important strategic scarce resource. Presently, helium used in industry originates primarily from natural gas. In contrast, helium in coal measures, generally emerging as coalbed methane (CBM) with a high helium content, serves as a vital supplement to conventional helium resources. In industry, helium extraction from boil off gas (BOG) during natural gas liquefaction is recognized as an important way to obtain helium resources. However, existing studies on helium in coal measures mostly focus on the genesis, enrichment patterns, and geochemical characteristics of helium, while there is a lack of studies on its resource characteristics and …


Effectiveness Assessment And Spatial Distribution Characteristics Of Helium Source Rocks In The Shixi Block Along The Eastern Margin Of The Ordos Basin, Chang Yangmei, Liu Chao, Sun Beilei Jun 2025

Effectiveness Assessment And Spatial Distribution Characteristics Of Helium Source Rocks In The Shixi Block Along The Eastern Margin Of The Ordos Basin, Chang Yangmei, Liu Chao, Sun Beilei

Coal Geology & Exploration

Background Helium gas serves as a significant rare strategic resource. In China, helium resources are relatively scarce and dependent heavily on imports. Therefore, there is a pressing need for the exploration and exploitation of helium resources. Helium source rocks provide a material basis for the formation of helium resources. The Zijinshan pluton serves as a principal source of coal-measure helium along the eastern margin of the Ordos Basin. Previous studies reveal that helium in natural gas within the Shixi Block originates primarily from the decay of radioactive elements in the deep part of the Jianjiagou-Zijinshan plutons. However, there is a …


Backfill-Strip Mining And Co2 Mineralization Sequestration In Coal Mine Goaves: A Synergetic Method And Its Key Technologies, Zhu Mengbo, Liu Lang, Wang Shuangming, Wei Baoning, Rong Ruoyu, Zhang Wenzhong, Zhuang Dengdeng, Jia Qifeng Jun 2025

Backfill-Strip Mining And Co2 Mineralization Sequestration In Coal Mine Goaves: A Synergetic Method And Its Key Technologies, Zhu Mengbo, Liu Lang, Wang Shuangming, Wei Baoning, Rong Ruoyu, Zhang Wenzhong, Zhuang Dengdeng, Jia Qifeng

Coal Geology & Exploration

Objective Coals serve as both the cornerstone of China’s energy security and important industrial raw materials. However, their mining and utilization tend to cause ecological and environmental problems such as CO2 emissions, the generation of solid wastes, and land subsidence. This necessitates reforming coal mining methods to promote the green, low-carbon, and sustainable development of China’s coal industry.Methods Through the comparative analysis of the conditions of CO2 sequestration in goaves corresponding to the caving, room-and-pillar (also known as knife-pillar), and backfill mining methods, this study developed a synergetic method for backfill-strip mining and CO2 mineralization sequestration …


Analyzing The Permeability Enhancement Effect Of Hydraulic Slotting For Low-Permeability Coal Seams Based On A Stress-Diffusion-Seepage Coupling Model, Zhang Hongtu, Zhou Tian, Wang Dengke, Li Botao, Luo Yong, Pan Rongsheng, Tang Jiahao, Lu Weiyong Jun 2025

Analyzing The Permeability Enhancement Effect Of Hydraulic Slotting For Low-Permeability Coal Seams Based On A Stress-Diffusion-Seepage Coupling Model, Zhang Hongtu, Zhou Tian, Wang Dengke, Li Botao, Luo Yong, Pan Rongsheng, Tang Jiahao, Lu Weiyong

Coal Geology & Exploration

Objective and Methods This study aims to improve the permeability enhancement effect of coal seams for gas drainage. Targeting the soft, low-permeability coal seams with complex gas occurrence conditions in the Baiping mining area and considering the impacts of effective stress, gas migration, actual gas effects, and tortuosity, this study constructed a stress-diffusion-seepage coupling model based on the pore-fracture dual medium assumption. Using the coupling model, this study simulated the variation patterns of gas content in coal seams during gas drainage under varying gas contents and borehole spacings. Through field tests under different permeability enhancement measures and unloaded coal amounts …


Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu Jun 2025

Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu

Coal Geology & Exploration

Objective During fire prevention and extinguishment for mines, injecting normal-temperature nitrogen into goaves can only play an inerting role. Meanwhile, the preparation of liquid nitrogen is complicated and costly. Therefore, in the Wudong Coal Mine in Xinjiang, low-temperature gaseous nitrogen of –40 ℃ was prepared using nitrogen cooling devices and then injected into goaves to prevent the spontaneous combustion of residual coals. However, the influencing patterns of low-temperature nitrogen on the pore structures and oxidation characteristics of residual coals in goaves remain poorly understood. This tends to affect the prediction and forecast of the secondary oxidation of residual coals in …


Chemical Temporary Plugging-Based Full-Bore Reconstruction Technology For Old Wellbores For The Collaborative Production Of Tight-Sand Gas And Deep Coalbed Methane, Yang Fan, Tan Zhanglong, Hu Jiachen, An Qi, Li Yu, Yang Ruiyue, Lin Junwen, Sun Zening, Jing Meiyang Jun 2025

Chemical Temporary Plugging-Based Full-Bore Reconstruction Technology For Old Wellbores For The Collaborative Production Of Tight-Sand Gas And Deep Coalbed Methane, Yang Fan, Tan Zhanglong, Hu Jiachen, An Qi, Li Yu, Yang Ruiyue, Lin Junwen, Sun Zening, Jing Meiyang

Coal Geology & Exploration

Objective In China, the Ordos Basin boasts abundant coal-measure gas resources, holding considerable potential for resource development. As the development deepens, the proportion of depleted, stripper, and inefficient wells for tight-sand gas in coal measures has gradually decreased year by year. The collaborative production of tight-sand gas and deep coalbed methane (CBM) has emerged as a significant approach to effectively releasing production capacity.Methods To achieve the reconstruction of old wellbores and commingled production of new and old layers, this study proposed a technology of chemical temporary plugging-based full-bore reconstruction of old wellbores of tight-sand gas combined with the large-scale …


Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin Jun 2025

Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) has emerged as a hot topic in CBM resource development. However, deep CBM has characteristics such as great burial depths, complex stress environments, and strong reservoir heterogeneity, which seriously restrict sweet spot prediction and accurate well location deployment in its large-scale exploitation. Methods This study investigated a deep CBM field along the eastern margin of the Ordos Basin. Using sonic, density, and caliper logging, this study developed a coal structure index model for deep coals. By introducing the coal structure index based on the coal structure differences in deep coal seams and combining factors including …


The Borehol Wall Image Digital Description Method Of The Overlying Rock Structural Planes Evdution Process In Deep Mining, Wang Jinchao, Zou Junpeng, Li Shenghai, Wang Chao, Li Xiaobin Jun 2025

The Borehol Wall Image Digital Description Method Of The Overlying Rock Structural Planes Evdution Process In Deep Mining, Wang Jinchao, Zou Junpeng, Li Shenghai, Wang Chao, Li Xiaobin

Coal Geology & Exploration

Objective In China, as mineral resource mining is increasingly expanding towards the deep parts of the Earth, the safe and efficient exploitation of deep resources has become a major strategic and technological challenge at the national level to be addressed urgently. Understanding the movement patterns of mining-affected strata in deep environments will assist in improving the intelligent prevention and control of mine disasters, thereby ensuring the safe and efficient exploitation of deep resources. Methods Targeting the complex and diverse forms of the overburden’s structural planes in deep mining, as well as a lack of characterization methods tailored to the evolutionary …


A Method Integrating A Non-Stationary Random Field For Constrained Inversion Of Csamt Data, Dai Qianwei, Guo Luyao, Wu Yun, Xiong Zhexian, Duan Dan, Bao Zhonglin, Wu Hongfei, Hao Fengyun Jun 2025

A Method Integrating A Non-Stationary Random Field For Constrained Inversion Of Csamt Data, Dai Qianwei, Guo Luyao, Wu Yun, Xiong Zhexian, Duan Dan, Bao Zhonglin, Wu Hongfei, Hao Fengyun

Coal Geology & Exploration

Objective The inversion of controlled-source audio-frequency magnetotelluric (CSAMT) data remains challenging due to two key issues: computational efficiency and resolution. To tackle these two issues, especially the over-smoothing effect caused by traditional regularization methods in estimating complex geological structures, this study proposed an improved regularization inversion method to reflect the spatial distribution characteristics of subsurface physical property parameters more accurately. Methods The proposed method was developed using the method for establishing the stochastic partial differential equation (SPDE) based on the Matérn covariance function. By introducing vector fields and the shape parameters of a range ellipse, this method fully considered both …


A Visual Positioning Method For Tunnel Boring Machines In Underground Coal Mines Based On Anchor Net Features, Zhang Xuhui, Chi Yunkai, Du Yuyang, Jiang Junying, Yang Wenjuan, Zhao Youjun, Wan Jicheng, Wang Yanqun, Tian Chenhui Jun 2025

A Visual Positioning Method For Tunnel Boring Machines In Underground Coal Mines Based On Anchor Net Features, Zhang Xuhui, Chi Yunkai, Du Yuyang, Jiang Junying, Yang Wenjuan, Zhao Youjun, Wan Jicheng, Wang Yanqun, Tian Chenhui

Coal Geology & Exploration

Background Precise positioning of tunnel boring machines (TBMs) in underground coal mines plays a fundamental role in the automated and intelligent guidance and control of fully mechanized heading face. However, traditional visual positioning methods show limited application effects in underground roadways due to their narrow and enclosed spaces, insufficient illumination, and sparse textures. This study proposed a visual positioning method for TBMs in underground coal mines based on anchor net features.Methods A three-stream depthwise separable convolutional neural network (TSCR-NET) for image enhancement was employed to estimate the reflection, illumination, and noise in images individually. Through illumination adjustment while suppressing …


Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati Jun 2025

Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati

Makara Journal of Science

The growth of a porous anodic aluminum oxide (PAAO) layer with fewer cracks on a tubular substrate is quite challenging. The PAAO layer on a curved surface grows slower than that on a flat surface and is susceptible to cracking. This study aims to improve the crack resistance of the PAAO layer grown on a tubular aluminum substrate by adding ethylene glycol (EG). Each bath contained additive concentrations of 0, 5, 10, and 15 vol% EG. Anodization proceeded for 4 h at a temperature of 10 ℃ using the potentiostatic mode at 25 V in a sulfuric acid bath and …


Synthesis Of Carboxymethyl Cellulose From Nypa Fruticans For Coating Metformin On Zn-Based Metal-Organic Framework Nanohybrid As A Bionanocomposite Drug Delivery System, Delviani Delviani, Viola Giary Rizkillah Maharani, Putri Nur Shadrina, Tri Warni, Regina Wan Azizah, Indra Lasmana Tarigan, Madyawati Latief Jun 2025

Synthesis Of Carboxymethyl Cellulose From Nypa Fruticans For Coating Metformin On Zn-Based Metal-Organic Framework Nanohybrid As A Bionanocomposite Drug Delivery System, Delviani Delviani, Viola Giary Rizkillah Maharani, Putri Nur Shadrina, Tri Warni, Regina Wan Azizah, Indra Lasmana Tarigan, Madyawati Latief

Makara Journal of Science

Diabetes is a common and rapidly spreading disease that affects 6.6% of the world’s population. Metformin hydrochloride (HCl) is an effective oral pharmacological treatment for type 2 diabetes mellitus (T2DM) patients because of its capability to reduce glucose levels and the risk of hypoglycaemia. However, gastrointestinal sensitivities to this drug can cause diarrhoea, nausea, vomiting and stomach ache. An alternative is controlled release technology by coating metformin with carboxymethyl cellulose (CMC) and zinc-metal-organic framework (Zn-MOF) through the encapsulation method. Therefore, this study aimed to coat metformin formulations using CMC in a Zn-MOF to control release into the body and minimise …


Removal Of Heavy Metals From Motorcycle Washing Wastewater Using A Zeolite-Embedded Sheet, Noverita Dian Takarina, Hanies Ambarsari, Sekar Arum Pramudyawardhani, Maria Fatima Niken Kris Rahmawati, Erni Johan, Naoto Matsue, Mohammad Afdhal Adidharma Jun 2025

Removal Of Heavy Metals From Motorcycle Washing Wastewater Using A Zeolite-Embedded Sheet, Noverita Dian Takarina, Hanies Ambarsari, Sekar Arum Pramudyawardhani, Maria Fatima Niken Kris Rahmawati, Erni Johan, Naoto Matsue, Mohammad Afdhal Adidharma

Makara Journal of Science

The increased use of motorcycles for transportation has heightened environmental challenges related to their washing, particularly the discharge of untreated wastewater containing heavy metals, such as copper (Cu) and lead (Pb), into drainage systems. This study explored the effectiveness of zeolite-embedded sheets (ZESs) in the removal of these pollutants from motorcycle washing wastewater. ZESs were prepared through treatment of nonwoven sheets with Linder Type A (LTA Zeolite) powder and heat treatment, washing, and drying. Characterization was performed via scanning electron microscopy with energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy. Over a 60 min adsorption period, the ZES achieved removal …


Spatiotemporal Evaluation Of Water Quality, Metal Pollution, And Human Health Risks In A Dredged Urban River, New Jersey, Usa, Oluwafemi Soetan, Qingzhi Zhu, Huan Feng Jun 2025

Spatiotemporal Evaluation Of Water Quality, Metal Pollution, And Human Health Risks In A Dredged Urban River, New Jersey, Usa, Oluwafemi Soetan, Qingzhi Zhu, Huan Feng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Although the short-term effectiveness of remedial sediment dredging (RSD) on mitigating sediment contamination in the lower Passaic river (LPR), New Jersey, USA, was previously established in previous studies, dredging impacts on overlying water and consequential effects on aquatic life and human health were not investigated through model-based risk assessment methods. This study assessed the influence of RSD on metal pollution and toxicological risks upstream and downstream of River Mile-3.4, which was the subject of a 2012 RSD. Over the pre-, during-, and post-dredging periods, threats to aquatic life and humans were greater upstream at River Mile-4 (WQIavg. ≥ 50, PIavg. …


Parity-Time Symmetry In Vcsels Utilizing Lithographic Cavities, Abdullah Demi̇r Jun 2025

Parity-Time Symmetry In Vcsels Utilizing Lithographic Cavities, Abdullah Demi̇r

Turkish Journal of Physics

Parity-time symmetry (PTS) has emerged as a powerful strategy for engineering single-mode lasers with enhanced mode selectivity. In this work, we present a systematic numerical study comparing two classes of non-Hermitian micro-laser designs: PTS and quasi-PTS (q-PTS). Using lithographically defined vertical-cavity surface-emitting lasers (Li-VCSELs) as our platform, we show that q-PTS VCSELs offer superior transverse mode discrimination compared to their PTS counterparts. This advantage arises from the unique coupling mechanism in q-PTS architectures, where the fundamental mode preserves its low-loss nature. In contrast, PTS VCSELs require the second-order mode to remain in the PTS phase while the fundamental mode is …