检索结果-内蒙古大学图书馆

Nucleation effects of coccoliths in portland cement

Matter 2025年

作者： Beatty, Danielle N. Srubar, Wil V. Materials Science and Engineering Program University of Colorado Boulder 4001 Discovery Drive UCB 027 BoulderCO80303 United States Department of Civil Environmental and Architectural Engineering University of Colorado Boulder 1111 Engineering Drive ECOT 441 UCB 428 BoulderCO80309 United States

This work explores the use of photosynthesized coccoliths (intricate CaCO3 particles) as a nucleation agent or cement replacement in portland cement paste. First, coccoliths were produced and harvested from the marine microalgae Emiliania huxleyi and the particle size, morphology, and mineralogy were characterized. Then, the nucleation effects of E. huxleyi coccoliths as seeding agent (0.5, 1, 3, or 5 wt % additions) and limestone filler (5 and 15 wt % cement replacements) were studied using isothermal conduction calorimetry and compressive strength testing. The results were compared with five commercially available CaCO3 sources used as nucleation agents and fillers. While the high surface area of coccoliths (12.22 m2/g) enhanced water demand, it also enhanced nucleation during cement hydration without accelerating hydration, leading to enhanced early-age strength without detriments to 28-day strength. Results highlight a potential carbon reduction strategy, namely employing photosynthesis as a method of mineral admixture production, for the cement and concrete industry. © 2025 Elsevier Inc.

关键词： Portland cement

来源：评论

学校读者我要写书评

暂无评论

Flood Modelling for an Urban Indian Catchment: Challenges and Way Forward

Flood Modelling for an Urban Indian Catchment: Challenges an...

引用

Virtual Conference on Disaster Risk Reduction, VCDRR 2021

作者： Ghosh, Mousumi Karmakar, Subhankar Ghosh, Subimal Interdisciplinary Program in Climate Studies Indian Institute of Technology Bombay Mumbai400076 India Environmental Science and Engineering Department Indian Institute of Technology Bombay Mumbai400076 India Centre for Urban Science and Engineering Indian Institute of Technology Bombay Mumbai400076 India Department of Civil Engineering Indian Institute of Technology Bombay Mumbai400076 India

ISBN: (纸本)9789811655005

The current study aims to develop a holistic hydrodynamic flood modelling framework for the Mithi catchment of Mumbai city, India, which is subjected to flooding almost every year causing huge losses and inconvenience. A one-dimensional flood model (MIKE 11) which accounts for the river discharge along with stormwater drainage discharge is coupled with a two-dimensional flood model (MIKE 21) which simulates the overland flow in the MIKE FLOOD platform along with the major flood influencers such as rainfall and tidal elevation to develop a three-way coupled flood modelling framework. The flood parameters obtained from this framework are translated into flood inundation maps which account for flood depth and flood hazard maps which account for flood depth along with spatial velocity and can help to identify the potential areas at risk. However, hydrodynamic flood modelling is highly data-intensive and requires good resolution meteorological, hydraulic, and topographical data sets. Therefore, the unavailability of long-term and reliable data sets in developing and underdeveloping countries cause a major hindrance for modelling in such catchments. The current study also adapts alternate robust methods to address the challenge of data scarcity of rainfall, discharge, tidal elevation, and drainage network. The proposed framework and methods are generic and can be incorporated in similar data-scarce urban catchments for effective flood management. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Hydrodynamics

来源：评论

学校读者我要写书评

暂无评论

Epilithic biofilm as a potential biomonitor for microplastics contamination in Brantas River of Malang City, Indonesia

引用

Case Studies in Chemical and environmental engineering 2025年 11卷

作者： Anggayasti, Wresti L. Pramudia, Zulkisam Susanti, Yogita A.D. Al Zamzami, Ilham Misbakudin Moehammad, Khibar Syiar Wardana, I Nyoman Gede Kurniawan, Andi Environmental Sciences Study Program of Universitas Brawijaya Malang Indonesia Aquaculture Study Program Faculty of Fisheries and Marine Science Universitas Brawijaya Malang Indonesia Aquatic Resources Management Study Program Faculty of Fisheries and Marine Science Universitas Brawijaya Malang Indonesia Mechanical Engineering Department Faculty of Engineering Universitas Brawijaya Malang Indonesia

Despite being an efficient bioremediation agent, aquatic biofilm's usefulness as a biomonitor has not been explored extensively. This study disclosed the potential of epilithic biofilm as biomonitor by comparing its metagenomics with water quality parameters and microplastic count in Brantas River. Metagenomics showed the epilithic biofilm was dominated by Exiguobacterium, which recognizes and degrades microplastics, along with Rhodobacterium and Rhizobiales. For the first time, biofilm microbes and their respective roles were discovered to correspond to the total microplastic counts in comparison with BOD as the only transgressing physicochemical parameter. Thus, epilithic biofilm is a potential biomonitor for riverine microplastic contaminations. © 2024 The Author(s)

关键词： Epilithic biofilm Metagenomics Microplastic biomonitor River pollution Water physicochemical parameters

来源：评论

学校读者我要写书评

暂无评论

GPU Implementation of a Gas-Phase Chemistry Solver in the CMAQ Chemical Transport Model

ACS ES&T air

引用

ACS ES&T air 2025年第2期2卷 226-235页

作者： Duncan Quevedo Khanh Do George Delic José Rodríguez-Borbón Bryan M Wong Cesunica E Ivey Department of Civil and Environmental Engineering University of California Berkeley California 94720 United States. Department of Chemical and Environmental Engineering University of California Riverside California 92557 United States. Center for Environmental Research and Technology Riverside California 92507 United States. Hiperism Consulting LLC Chapel Hill North Carolina 27514 United States. Department of Chemistry Department of Physics & Astronomy and Material Science & Engineering Program University of California Riverside California 92557 United States.

The Community Multiscale Air Quality (CMAQ) model simulates atmospheric phenomena, including advection, diffusion, gas-phase chemistry, aerosol physics and chemistry, and cloud processes. Gas-phase chemistry is often a major computational bottleneck due to its representation as large systems of coupled nonlinear stiff differential equations. We leverage the parallel computational performance of graphics processing unit (GPU) hardware to accelerate the numerical integration of these systems in CMAQ's CHEM module. Our implementation, dubbed CMAQ-CUDA, in reference to its use in the Compute Unified Device Architecture (CUDA) general purpose GPU (GPGPU) computing solution, migrates CMAQ's Rosenbrock solver from Fortran to CUDA Fortran. CMAQ-CUDA accelerates the Rosenbrock solver such that simulations using the chemical mechanisms RACM2, CB6R5, and SAPRC07 require only 51%, 50%, or 35% as much time, respectively, as CMAQv5.4 to complete a chemistry time step. Our results demonstrate that CMAQ is amenable to GPU acceleration and highlight a novel Rosenbrock solver implementation for reducing the computational burden imposed by the CHEM module.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Analysis of marine debris at Alue Naga and Ulee Lheue beaches in Banda Aceh City using the transect method

引用

Materials Today: Proceedings 2022年 63卷 S339-S345页

作者： Windari, Wulan Saiful, Saiful Gani, Asri Mahidin Master of Environment Management Postgraduate Program Syiah Kuala University Banda Aceh Indonesia Chemistry Department Faculty of Mathematics and Natural Science Syiah Kuala University Banda Aceh Indonesia Chemical Engineering Faculty of Engineering Syiah Kuala University Banda Aceh Indonesia Research Center for Environmental and Natural Resources Universitas Syiah Kuala Darussalam Banda Aceh 23111 Indonesia

Alue Naga Beach and Ulee Lheue Beach are beaches located in Banda Aceh City, Aceh Province, these two beaches have a fairly large role in the fields of fisheries, transportation, and tourism. During the last few years, the population growth rate of Banda Aceh City has increased by 2% per year, this causes the volume of waste generated to be even greater, unfortunately, the municipal waste management office cannot manage it fully. Most of the untreated waste enters water bodies and has the potential to pollute the marine and coastal environment. So it is necessary to do research to provide an overview of the level of marine debris pollution on the two beaches. This study uses the transect method, the waste obtained is grouped according to size and type. The results showed that marine debris on Ulee Lheue beach was found to be more numerous and varied than marine debris on Alue Naga beach. Overall, macro waste with a size range of 2.5−1 m was the most commonly found and plastic was the waste with the highest yield with a density value of 65.8 g/m2, an abundance of 6.56 items/m2, and a percentage of 75%. © 2022

关键词： Beaches

来源：评论

学校读者我要写书评

暂无评论

Mathematical Modelling and Comparative Analysis of Three Treatment Technologies for Upgrading Wastewater Treatment Plants: A Case Study of Biofilm Reactors in El-Gouna, Egypt

SSRN

引用

SSRN 2023年

作者： Osama, Ashrakat Kinnawy, Mohab A. Moussa, Mostafa S. Riechelmann, Carsten Hosney, Hadeel Environmental Engineering Program Zewail City of Science and Technology Giza Egypt Sustainable Development Center Zewail City of Science and Technology Giza Egypt Zewail City of Science and Technology Giza Egypt Environmental Engineering Faculty of Engineering Mataria Helwan University Egypt Technische Universität Berlin Germany Water Supply Sanitation and Environmental Engineering Department IHE Delft Institute for Water Education Delft Netherlands

Moving Bed Biofilm Reactors (MBBRs) has been preferred over conventional processes with suspended biomass in recent years. The main reason behind this preference is that it can achieve better removal efficiencies than conventional systems in a smaller footprint. However, unlocking the full potential behind MBBRs in large-scale WWTPs is still a challenge in real life. In this paper, the performance of three different treatment technologies: Extended Aeration Activated Sludge (EAAS), Integrated Fixed Biofilm Reactor (IFAS) and the Hybrid Moving Bed Biofilm Reactor (HMBBR), was investigated over a year in a WWTP located in El-Gouna, Egypt. The COD removal efficiency amongst the three systems was comparable, with EAAS achieving 93.5%, IFAS 94%, and HMBRR 95%. Nevertheless, the NH4 removal efficiency for EAAS was slightly lower at 97.5%, compared to IFAS and HMBBR, both achieving removal efficiency of 98%. All three systems operated below their designed capacity for influent flow and organic load. BioWin Software was able to mimic the real case of the WWTP of El-Gouna and critically defined all plant limitations and operational data. Different simulations were modelled to test the three systems' hydraulic and organic loading capacities using different scenarios and operating conditions. The HMBBR system failed to withstand the increase in organic loads, due to the sloughing effect. The biomass sloughing overloads the reactor volume, where the liquid, biomass and media volumes exceed the reactor volume, leading to an adverse effect contradicting the primary purpose of adding media carriers. Model simulations and data analysis findings were able to recommend the most suited setup for upgrading an existing system by attached growth technique, with all kinetic parameters and operational conditions. © 2023, The Authors. All rights reserved.

关键词： Biomass

来源：评论

学校读者我要写书评

暂无评论

Alert and Response of Earthquake and Tsunami for Community Based Disaster Risk Reduction 2

Alert and Response of Earthquake and Tsunami for Community B...

引用

2nd International Conference on sciences and Technology Applications, ICOSTA 2020

作者： Retno Susilorini, Rr M. I. Pamudji, Andre Kurniawan Sanjaya, Ridwan Ismail, Amrizarois Amasto, Ardhito Hayyu Department of Infrastructure and Environmental Engineering Faculty of Environmental Science and Technology Soegijapranata Catholic University Semarang Indonesia Master Program of Environmental and Urban Studies Faculty of Environmental Science and Technology Soegijapranata Catholic University Semarang Indonesia Department of Information System Faculty of Computer Science Soegijapranata Catholic University Semarang Indonesia

Indonesia had been suffered by earthquake and tsunami for many centuries. Since many lives have taken by tsunami strikes, alert and response system are very important as important part of Disaster Risk Reduction, especially in area with high population density. This research conducted in Kangkung fishing village in Bandar Lampung coastal area which is an earthquake and tsunami prone area. The aim of the research is to study alert and response of Community Based Disaster Risk Reduction. The research conducted by qualitative method and purposive-descriptive approach. There were 53 respondents which participated in the survey and interview. It is reported that "Smart Resilient City"model suitable for community needs of alert and response of earthquake and tsunami disaster. This research meets conclusion that "Smart Resilient City"model may become a great solution in Community Based Disaster Risk Reduction to cope with the hazard of earthquake and tsunami comprehensively and sustainably. © Published under licence by IOP Publishing Ltd.

关键词： Surveys

来源：评论

学校读者我要写书评

暂无评论

Chemical precipitation of nanocrystalline hydroxyapatite with calcium carbonate derived from green mussel shell wastes and several phosphorus sources

引用

Case Studies in Chemical and environmental engineering 2025年 11卷

作者： Naubnome, V. Prihanto, A. Schmahl, W.W. Pusparizkita, Y.M. Ismail, R. Jamari, J. Bayuseno, A.P. Department of Mechanical Engineering Diponegoro University Tembalang Semarang Indonesia Chemical Engineering Vocational Program Catholic Polytechnic Mangun Wijaya Semarang Indonesia Department of Earth and Environmental Science Ludwig Maximillian University of Munich Germany Department of Environmental Engineering Diponegoro University Semarang Indonesia

This work reports on a chemical precipitation experiment to produce nanocrystalline calcium hydroxyapatite (Ca-HA) using a calcium carbonate precursor derived from green mussel shells. Ammonium biphosphate and phosphoric acid were mixed with the precursor, achieving a pH of 13–14 by stirring magnetically at 30 °C for 48 hours. The nanocrystalline Ca-HA product (8–13 nm) was validated through X-ray diffraction and Fourier-transform infrared spectroscopy with an average calcium-to-phosphorus ratio molar of 1.8, influencing the thermal stability according to thermogravimetric and differential thermal analysis. Green mussel shell wastes are a recyclable calcium resource potentially used to synthesize nanocrystalline hydroxyapatite. © 2025 The Authors

关键词： Calcium carbonate Chemical precipitation Green mussel shell waste Nanocrystalline hydroxyapatite Thermal stability

来源：评论

学校读者我要写书评

暂无评论

Reviving the Absorbent Chemistry of Electrochemically Mediated Amine Regeneration for Improved Point Source Carbon Capture

SSRN

引用

SSRN 2023年

作者： Hassan, Ahmad Refaie, Abdelrahman Aleta, Prince Afshari, Mohsen Kalantari, Elmira Fang, Yuanyuan Rahimi, Mohammad Mim Department of Civil and Environmental Engineering University of Houston HoustonTX77204 United States Materials Science and Engineering Program University of Houston HoustonTX77204 United States

Electrochemically mediated amine regeneration (EMAR) is emerging as a promising electrochemical approach for carbon capture from point sources. In this study, for the first time, the absorbent chemistry of the EMAR process was revived by considering criteria beyond metal-amine complexation. The systematic investigation focused on using secondary amines, which were previously overlooked in EMAR due to limited metal-amine interaction, despite their proven effectiveness in conventional carbon capture processes. The integration of secondary amines— monoethanolamine (MEA), aminomethyl propanol (AMP), and methyldiethanolamine (MDEA)—with the benchmark ethylenediamine (EDA) was thoroughly studied, evaluating their impact on absorption and desorption kinetics and capacities, and electrochemical performance. Among the blends, EDA+MDEA emerged as the top performer, particularly excelling in electrochemical aspects. The charge transfer resistance (RCT) of the deposition reaction, as the rate-limiting step, for the EDA+MDEA blend was reduced by 40% compared to pure EDA, and the heterogeneous electron transfer rate constant (k0) improved threefold. In the bench-scale assessments, the EDA+MDEA blend showed a notable decrease in desorption energetics to 37 kJ/molCO2, marking a 34% reduction compared to the 56 kJ/molCO2 required for pure EDA. This marks the lowest reported energetics for an EMAR process targeting point source carbon capture. This research paves the way for future systematic investigations of a wider range of amine blends for EMAR and eventually the process implementation at larger scales. © 2023, The Authors. All rights reserved.

关键词： Amines

来源：评论

学校读者我要写书评

暂无评论

Integrating Land Use Changes,Biomass Dynamics,and Water Quality for Wetland Restoration:A Case Study of Chaohu Lake Shibalianwei Wetland,China

引用

Journal of Geoscience and Environment Protection 2025年第4期13卷 366-392页

作者： Sajida Changming Yang Wazir Aitizaz Ahsan Zifang Wang College of Environmental Science and Engineering Tongji UniversityShanghaiChina UNEP-Tongji Institute of Environment for Sustainable Development(IESD) ShanghaiChina Ph.D.Program of Aquatic Science and Technology Kaohsiung University of Science and TechnologyKaohsiungChina Science and Technology R&D Center Ouyeel Lianjin Recycling Resources Co.Ltd.ShanghaiChina

Wetlands are essential ecosystems that provide critical environmental services,including nutrient retention,water purification,biodiversity conservation,and climate ***,anthropogenic activities such as urban expan-sion,agricultural runoff,and industrial pollution have severely degraded these ecosystems,necessitating targeted restoration *** study assesses the effectiveness of restoration interventions in the Shibalianwei Wetland,a key component of the Chaohu Lake basin,by analyzing land use changes,biomass recovery,and water quality *** strategies included veg-etation re-establishment,hydrological modifications,and adaptive seasonal management over multiple *** findings indicate substantial improve-ments in water quality,with Total Nitrogen(TN)and Total Phosphorus(TP)concentrations in the wetland outflow reduced by up to 52%and 50%,respec-tively,during peak vegetation *** Oxygen(DO)levels con-sistently remained above 6.2 mg/L,while Chemical Oxygen Demand(COD)declined by 38%during the summer *** enhancements were strongly correlated with increased aboveground biomass(AGB),particularly in areas of restored vegetation,which peaked at 10,211 tons in ***,subsequent declines in vegetation cover emphasized the challenges in sustaining long-term ecological gains due to seasonal variability and external *** study highlights the importance of integrated ecological restoration strategies and positions the Shibalianwei Wetland as a significant buffer against eutrophica-tion,contributing to the overall water quality improvement of Chaohu *** results offer a scalable framework for restoring degraded wetland ecosys-tems and underscore the necessity for long-term monitoring,adaptive man-agement strategies,and policy interventions to ensure sustainable restoration *** integrating land use,biomass recovery,and water quality assess-ments,this research provides valuable insig

关键词： Wetland Restoration Assessment Chaohu Lake Land Use Changes Aboveground Biomass Water Quality

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：