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20 pages, 6150 KiB  
Article
Evolution of Permian Sedimentary Environment in South China: Constraints on Heterogeneous Accumulation of Organic Matter in Black Shales
by Weibing Shen, Weibin Shen, Xiao Xiao and Shihao Shen
Minerals 2025, 15(3), 296; https://doi.org/10.3390/min15030296 - 14 Mar 2025
Viewed by 592
Abstract
Permian black shale, as a potential target for marine shale gas exploration in South China, is characterized by its great thickness and organic matter (OM) content. To understand the constraints on the heterogeneous accumulation of OM in Permian black shale, high-resolution geochemical data [...] Read more.
Permian black shale, as a potential target for marine shale gas exploration in South China, is characterized by its great thickness and organic matter (OM) content. To understand the constraints on the heterogeneous accumulation of OM in Permian black shale, high-resolution geochemical data related to paleoenvironment variations are collected on the Gufeng and Dalong Formations of the Putaoling area, the Anhui province, and the Lower Yangtze area. The OM was heterogeneously enriched in the Permian shales, as shown by the highly organic-matter-rich Gufeng Formation and the moderately organic-matter-rich Dalong Formation. The distribution patterns of rare earth elements (REEs) indicate a stably high sedimentary rate throughout the shale deposition. Redox indexes, including MoEF, UEF, V/Sc, and U/Th, indicate anoxic conditions for the deposition of the Gufeng and Dalong Formations, and that seawater oxygenation has occurred. The stratigraphic decreases in the (Fe+Mn)/Ti ratios, the index of chemical alteration (CIA), and the content of nutrient elements demonstrate the upward weakening patterns of hydrothermal activity and chemical weathering, which result in a reduction in the primary production. The redox state combined with the primary production jointly control the heterogeneous accumulation of OM in the Permian shales. Our paleoenvironmental evolution model for OM accumulation in the black shales indicates that the Gufeng Formation might be the priority object for the exploration of shale gases in the Permian strata within the Lower Yangtze area. Full article
(This article belongs to the Special Issue Element Enrichment and Gas Accumulation in Black Rock Series)
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83 pages, 5867 KiB  
Review
Fouling of Reverse Osmosis (RO) and Nanofiltration (NF) Membranes by Low Molecular Weight Organic Compounds (LMWOCs), Part 1: Fundamentals and Mechanism
by Yasushi Maeda
Membranes 2024, 14(10), 221; https://doi.org/10.3390/membranes14100221 - 17 Oct 2024
Cited by 6 | Viewed by 6201
Abstract
Reverse osmosis (RO) and nanofiltration (NF) are ubiquitous technologies in modern water treatment, finding applications across various sectors. However, the availability of high-quality water suitable for RO/NF feed is diminishing due to droughts caused by global warming, increasing demand, and water pollution. As [...] Read more.
Reverse osmosis (RO) and nanofiltration (NF) are ubiquitous technologies in modern water treatment, finding applications across various sectors. However, the availability of high-quality water suitable for RO/NF feed is diminishing due to droughts caused by global warming, increasing demand, and water pollution. As concerns grow over the depletion of precious freshwater resources, a global movement is gaining momentum to utilize previously overlooked or challenging water sources, collectively known as “marginal water”. Fouling is a serious concern when treating marginal water. In RO/NF, biofouling, organic and colloidal fouling, and scaling are particularly problematic. Of these, organic fouling, along with biofouling, has been considered difficult to manage. The major organic foulants studied are natural organic matter (NOM) for surface water and groundwater and effluent organic matter (EfOM) for municipal wastewater reuse. Polymeric substances such as sodium alginate, humic acid, and proteins have been used as model substances of EfOM. Fouling by low molecular weight organic compounds (LMWOCs) such as surfactants, phenolics, and plasticizers is known, but there have been few comprehensive reports. This review aims to shed light on fouling behavior by LMWOCs and its mechanism. LMWOC foulants reported so far are summarized, and the role of LMWOCs is also outlined for other polymeric membranes, e.g., UF, gas separation membranes, etc. Regarding the mechanism of fouling, it is explained that the fouling is caused by the strong interaction between LMWOC and the membrane, which causes the water permeation to be hindered by LMWOCs adsorbed on the membrane surface (surface fouling) and sorbed inside the membrane pores (internal fouling). Adsorption amounts and flow loss caused by the LMWOC fouling were well correlated with the octanol-water partition coefficient (log P). In part 2, countermeasures to solve this problem and applications using the LMWOCs will be outlined. Full article
(This article belongs to the Collection Featured Reviews in Membrane Science)
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21 pages, 5914 KiB  
Article
Removal of Micropollutants in Water Reclamation by Membrane Filtration: Impact of Pretreatments and Adsorption
by Juan C. Aldana, Cristina Agudelo, Pedro M. Álvarez and Juan L. Acero
Membranes 2024, 14(7), 146; https://doi.org/10.3390/membranes14070146 - 27 Jun 2024
Cited by 1 | Viewed by 2343
Abstract
Organic micropollutants (OMPs) present in water and wastewater are in the spotlight because of their potentially harmful effects even at low concentrations and the difficulties of their elimination in urban wastewater treatment plants (UWWTPs). This study explores the impact of some membrane filtration [...] Read more.
Organic micropollutants (OMPs) present in water and wastewater are in the spotlight because of their potentially harmful effects even at low concentrations and the difficulties of their elimination in urban wastewater treatment plants (UWWTPs). This study explores the impact of some membrane filtration processes on the removal of a group of 11 OMPs with an eye on the effects of two pretreatments (i.e., coagulation and adsorption onto powdered activated carbon (PAC)) and the adsorption of OMPs onto the membranes on the overall removal. For this purpose, ultrafiltration (UF) and nanofiltration (NF) experiments were conducted with selected OMPs spiked in ultrapure water and secondary effluents from UWWTPs. It was observed that the adsorption of OMPs onto the membranes was influenced by the characteristics of the membranes, as well as the presence of effluent organic matter (EfOM). Since adsorption was the dominant mechanism for the rejection of OMPs by UF membranes, a study of the adsorption equilibrium of the micropollutants using UF membrane pieces as the adsorbent was conducted. The adsorption isotherms for the most hydrophobic OMPs fitted the Langmuir model. The efficiency of coagulation and powdered activated carbon (PAC) adsorption coupled with UF were also investigated. Both pretreatments alleviated membrane fouling and improved the rejection of organic and inorganic matter. The PAC pretreatment significantly improved the removal of OMPs in the combined PAC/UF process. The best options for achieving reclaimed water with satisfactory physicochemical quality, nearly devoid of OMPs and microorganisms, and suitable for diverse reuse purposes are either the NF treatment or the combination of PAC/UF. Full article
(This article belongs to the Special Issue Advanced Membranes and Membrane Technologies for Wastewater Treatment)
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26 pages, 4848 KiB  
Article
Identification and Characterization of the Gene Responsible for the O3 Mating Type Substance in Paramecium caudatum
by Yuta Chiba, Yasuhiro Takenaka and Nobuyuki Haga
Microorganisms 2024, 12(3), 588; https://doi.org/10.3390/microorganisms12030588 - 15 Mar 2024
Cited by 1 | Viewed by 1803
Abstract
The process of sexual reproduction in eukaryotes starts when gametes from two different sexes encounter each other. Paramecium, a unicellular eukaryote, undergoes conjugation and uses a gametic nucleus to enter the sexual reproductive process. The molecules responsible for recognizing mating partners, hypothetically [...] Read more.
The process of sexual reproduction in eukaryotes starts when gametes from two different sexes encounter each other. Paramecium, a unicellular eukaryote, undergoes conjugation and uses a gametic nucleus to enter the sexual reproductive process. The molecules responsible for recognizing mating partners, hypothetically called mating-type substances, are still unclear. We have identified an O3-type mating substance polypeptide and its gene sequence using protein chemistry, molecular genetics, immunofluorescence, RNA interference, and microinjection. The O3-type substance is a polypeptide found in the ciliary membranes, located from the head to the ventral side of cells. The O3-type substance has a kinase-like domain in its N-terminal part located outside the cell and four EF-hand motifs that bind calcium ions in its C-terminal part located inside the cell. RNA interference and immunofluorescence revealed that this polypeptide positively correlated with the expression of mating reactivity. Microinjection of an expression vector incorporating the O3Pc-MSP gene (Oms3) induced additional O3 mating type in the recipient clones of different mating types or syngen. Phylogenetic analysis indicates that this gene is widely present in eukaryotes and exhibits high homology among closely related species. The O3Pc-MSP (Oms3) gene had nine silent mutations compared to the complementary mating type of the E3 homologue gene. Full article
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24 pages, 6918 KiB  
Article
Research of the Impact of Hydrogen Metallurgy Technology on the Reduction of the Chinese Steel Industry’s Carbon Dioxide Emissions
by Fang Wan, Jizu Li, Yunfei Han and Xilong Yao
Sustainability 2024, 16(5), 1814; https://doi.org/10.3390/su16051814 - 22 Feb 2024
Cited by 9 | Viewed by 4414
Abstract
The steel industry, which relies heavily on primary energy, is one of the industries with the highest CO2 emissions in China. It is urgent for the industry to identify ways to embark on the path to “green steel”. Hydrogen metallurgy technology uses [...] Read more.
The steel industry, which relies heavily on primary energy, is one of the industries with the highest CO2 emissions in China. It is urgent for the industry to identify ways to embark on the path to “green steel”. Hydrogen metallurgy technology uses hydrogen as a reducing agent, and its use is an important way to reduce CO2 emissions from long-term steelmaking and ensure the green and sustainable development of the steel industry. Previous research has demonstrated the feasibility and emission reduction effects of hydrogen metallurgy technology; however, further research is needed to dynamically analyze the overall impact of the large-scale development of hydrogen metallurgy technology on future CO2 emissions from the steel industry. This article selects the integrated MARKAL-EFOM system (TIMES) model as its analysis model, constructs a China steel industry hydrogen metallurgy model (TIMES-CSHM), and analyzes the resulting impact of hydrogen metallurgy technology on CO2 emissions. The results indicate that in the business-as-usual scenario (BAU scenario), applying hydrogen metallurgy technology in the period from 2020 to 2050 is expected to reduce emissions by 203 million tons, and make an average 39.85% contribution to reducing the steel industry’s CO2 emissions. In the carbon emission reduction scenario, applying hydrogen metallurgy technology in the period from 2020 to 2050 is expected to reduce emissions by 353 million tons, contributing an average of 41.32% to steel industry CO2 reduction. This study provides an assessment of how hydrogen metallurgy can reduce CO2 emissions in the steel industry, and also provides a reference for the development of hydrogen metallurgy technology. Full article
(This article belongs to the Special Issue Renewable Energy and Sustainable Energy Systems)
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11 pages, 1664 KiB  
Article
Effect of UV-LED Wavelength on Reactive Species Photogeneration from Dissolved Organic Matter
by Ze-Chong Guo, Lu Zhang, Yong Chen, Cheng Huang and Zhi-Min Liao
Water 2024, 16(5), 635; https://doi.org/10.3390/w16050635 - 21 Feb 2024
Viewed by 1842
Abstract
The photogeneration of reactive species from dissolved organic matter (DOM) plays a crucial role in the photochemical and photobiochemical processes in natural aquatic systems. However, the impact of the ultraviolet (UV) wavelength on the photogeneration of reactive species by different sources of DOM [...] Read more.
The photogeneration of reactive species from dissolved organic matter (DOM) plays a crucial role in the photochemical and photobiochemical processes in natural aquatic systems. However, the impact of the ultraviolet (UV) wavelength on the photogeneration of reactive species by different sources of DOM remains unclear. In this study, UV light at four wavelengths (365 nm, 310 nm, 280 nm, and 260 nm) provided by UV-LEDs were irradiated onto three types of DOM: humic acid (HA), fulvic acid (FA), and effluent organic matter (EfOM). Three reactive species produced by DOM, including excited triplet-state DOM (3DOM*), singlet oxygen (1O2), and hydroxyl radicals (•OH), were determined. UV365 proved to be the most efficient wavelength for generating 1O2 and •OH, with formation rates of 3.47 × 10−6 M s−1 and 1.67 × 10−8 M s−1, respectively, with the addition of FA and EfOM. The highest steady-state concentrations of all three reactive species were also generated under UV365, reaching 3.00 × 10−13 M (3DOM*) and 1.64 × 10−11 M (1O2) with the FA addition, and 1.44 × 10−10 M (•OH) with the EfOM. Across the different DOM sources, UV365 obtained the maximum quantum yields of reactive species, indicating the stronger effect of UV365 on inducing the photosensitization of DOM compared to the other shorter wavelengths. This study expands our understanding of the photochemistry of DOM in aquatic environments. Full article
(This article belongs to the Special Issue The Application of Electrochemical Methods in Water Treatment)
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16 pages, 3695 KiB  
Article
Quantifying the Impact of Organic Fertilizers on Soil Quality under Varied Irrigation Water Sources
by Shudong Lin, Qingyuan Lei, Yun Liu, Yimei Zhao, Lijun Su, Quanjiu Wang, Wanghai Tao and Mingjiang Deng
Water 2023, 15(20), 3618; https://doi.org/10.3390/w15203618 - 16 Oct 2023
Cited by 8 | Viewed by 5720
Abstract
The issues of limited water availability and excessive fertilizer utilization, both of which negatively impact soil health and crop productivity, are key focal points in the pursuit of sustainable agricultural progress. Given these crucial obstacles, it is crucial to utilize accurate methods of [...] Read more.
The issues of limited water availability and excessive fertilizer utilization, both of which negatively impact soil health and crop productivity, are key focal points in the pursuit of sustainable agricultural progress. Given these crucial obstacles, it is crucial to utilize accurate methods of irrigation and fertilization in order to improve the condition of the soil and promote the progress of sustainable farming. The objective of this research is to determine the optimal indicators for creating a minimal data set (MDS) that can assess the influence of organic fertilizers on the quality of pakchoi soil in varying irrigation water sources. Principal component analysis and norm values were utilized to create the MDS, and its accuracy was confirmed by examining coefficients of Nash efficiency and relative deviation. The results of our study showed that there was not much difference in soil bulk density (BD), but there was moderate variation in soil water content (SWC), soil salt content (SSC), alkali-hydrolyzed nitrogen (AN), available phosphorus (AP), available potassium (AK), and organic matter (OM). The selected MDS indicators included BD, AN, and OM. The soil quality index (SQI) achieved a high R2 value of 0.952, indicating a strong correlation. Furthermore, the nonlinear evaluation model showed a high level of effectiveness and efficiency, with Ef and Er values of 0.899 and 0.046, respectively. The effectiveness of this model in evaluating soil quality under different irrigation water conditions is evident. Notably, treatments involving magnetized–ionized brackish water (average SQI = 0.524) and the application of 20 kg/ha organic fertilizer (average SQI = 0.719) demonstrate the capacity to enhance soil quality. The present study presents a pragmatic, productive, and economical quantitative evaluation approach that can be used for worldwide vegetable farming with the utilization of clean water, saline water, magnetized–ionized saline water, and organic manure. Thus, we encourage vegetable growers to consider adopting both magnetized–ionized brackish water and organic fertilizers, and the utilization of the nonlinear soil quality index evaluation model is recommended as it offers a sensitive and effective approach to assessing soil quality across various irrigation and organic fertilizer schemes. Full article
(This article belongs to the Special Issue Sustainable Management of Agricultural Water)
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19 pages, 4028 KiB  
Article
Multiple Controls on Organic Matter Accumulation in the Intraplatform Basin of the Early Cambrian Yangtze Platform, South China
by Qiyang Zhang, Entao Liu, Songqi Pan, Hua Wang, Zhenhua Jing, Zhengfu Zhao and Ruiyue Zhu
J. Mar. Sci. Eng. 2023, 11(10), 1907; https://doi.org/10.3390/jmse11101907 - 2 Oct 2023
Cited by 6 | Viewed by 1878
Abstract
Studying the accumulation rules of organic matter (OM) in paleo-ocean sediments can not only enhance our understanding of how OM becomes enriched in ancient oceans but also provide guidance for the exploration of shale gas in unconventional shale strata. A breakthrough has been [...] Read more.
Studying the accumulation rules of organic matter (OM) in paleo-ocean sediments can not only enhance our understanding of how OM becomes enriched in ancient oceans but also provide guidance for the exploration of shale gas in unconventional shale strata. A breakthrough has been made in shale gas exploration in the early Cambrian Qiongzhusi Formation in South China. However, less attention has been paid to the intraplatform basin of the Yangtze Platform, and the factors controlling organic matter enrichment in this special region remain unclear. This study focuses on a continuous drilling core across the full well section of the Qiongzhusi Formation in the intraplatform basin of the Yangtze Platform. Through the comprehensive analysis of total organic carbon (TOC), major and trace elements, and Mo isotopes, this study investigates the controlling factors for OM enrichment with δ98/95Mo ratios utilized to identify the existence of euxinic bottom water. The examined 240 m long core can be divided into four units, where the TOC values of the lower Units 1 and 2 (0.2–5.0 wt.%) average higher than the upper Units 3 and 4 (0.2–2.5 wt.%). Redox indicators (U/Th, Ni/Co, EF(Mo)—EF(U)) indicate an increasing oxidation of bottom waters from the bottom upwards. δ98/95Mo data further confirm the presence of weakly euxinic conditions in Units 1 and 2, addressing the ongoing controversy surrounding bottom water redox environments. Primary productivity indicators (Ni/Al, Cu/Al) suggest a relatively low average productivity level within the intraplatform basin. The upwelling indicators EF(Co) * EF(Mn) of different profiles in the Yangtze Platform suggest that low productivity within the intraplatform basin can be mainly attributed to the absence of upwelling. Consequently, this study proposes an organic matter enrichment mechanism for the Qiongzhusi Formation in the intraplatform basin, which emphasizes the significance of the redox environment in the formation of high-quality hydrocarbon source rocks in restricted environments that lack upwelling, setting it apart from the deep ocean. These findings have the potential to provide valuable insights for the exploration of high-quality hydrocarbon source rocks in other similar regions. Full article
(This article belongs to the Special Issue High-Efficient Exploration and Development of Oil & Gas from Ocean)
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14 pages, 996 KiB  
Article
Optimization Modelling of the Decarbonization Scenario of the Total Energy System of Kazakhstan until 2060
by Nurkhat Zhakiyev, Ayagoz Khamzina, Svetlana Zhakiyeva, Rocco De Miglio, Aidyn Bakdolotov and Carmelina Cosmi
Energies 2023, 16(13), 5142; https://doi.org/10.3390/en16135142 - 3 Jul 2023
Cited by 10 | Viewed by 3245
Abstract
This research article provides a comprehensive scenario analysis of key structural changes in Kazakhstan’s fuel and energy complex subsectors until 2060, focusing on decarbonization efforts. The background places the issue of decarbonization in a broader context, considering the country’s vast size and sparse [...] Read more.
This research article provides a comprehensive scenario analysis of key structural changes in Kazakhstan’s fuel and energy complex subsectors until 2060, focusing on decarbonization efforts. The background places the issue of decarbonization in a broader context, considering the country’s vast size and sparse population. The study’s purpose involves analyzing the development of the climate agenda by comparing two scenarios: a “reference” scenario without decarbonization measures and a carbon neutrality scenario until 2060 (CN2060). A mathematical technical-economic model based on the TIMES paradigm (The Integrated MARKAL-EFOM System) serves as the method to optimize and simulate Kazakhstan’s energy system. The main findings reveal sets of policies, standards, and legislative, economic, and political decisions that are required to achieve CN2060. Additionally, the integration of a low-carbon policy, sectoral and cross-cutting approaches, the impact of the coronavirus crisis, the Russia-Ukraine conflict, and energy security issues receive a discussion. The article concludes with projected shares of generation and investment in renewable energy sources (RES) necessary for attaining CN2060. This work offers novel insights into challenges and opportunities for Kazakhstan’s transition to a low-carbon economy. Full article
(This article belongs to the Section B: Energy and Environment)
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14 pages, 2376 KiB  
Article
Evaluation of Efficiently Removing Secondary Effluent Organic Matters (EfOM) by Al-Based Coagulant for Wastewater Recycling: A Case Study with an Industrial-Scale Food-Processing Wastewater Treatment Plant
by Yu Cheng, Qiangqiang Cheng, Chengjin Zhao, Xianghao Ren, Yu Wang, Yingying Kou, Kangmin Chon, Myung-Han Ko and Moon-Hyun Hwang
Membranes 2023, 13(5), 510; https://doi.org/10.3390/membranes13050510 - 12 May 2023
Cited by 5 | Viewed by 2212
Abstract
The reuse of wastewater has been identified as an important initiative for the sustainable development of the environment; thus, the removal of secondary effluent organic matter (EfOM) to ensure the safety of reused wastewater is the key step and a subject of extensive [...] Read more.
The reuse of wastewater has been identified as an important initiative for the sustainable development of the environment; thus, the removal of secondary effluent organic matter (EfOM) to ensure the safety of reused wastewater is the key step and a subject of extensive research. In this study, Al2(SO4)3 and anionic polyacrylamide were selected as coagulant and flocculant, respectively, for the treatment of secondary effluent from a food-processing industry wastewater treatment plant to meet the standard regulatory specifications for water reuse. In this process, the removal efficiencies of chemical oxygen demand (COD), components with UV254, and specific ultraviolet absorbance (SUVA) were 44.61%, 25.13%, and 9.13%, respectively, with an associated reduction in chroma and turbidity. The fluorescence intensities (Fmax) of two humic-like components were reduced during coagulation, and microbial humic-like components of EfOM had a better removal efficiency because of a higher Log Km value of 4.12. Fourier transform infrared spectroscopy showed that Al2(SO4)3 could remove the protein fraction of the soluble microbial products (SMP) of EfOM by forming a loose SMP protein complex with enhanced hydrophobicity. Furthermore, flocculation reduced the aromaticity of secondary effluent. The cost of the proposed secondary effluent treatment was 0.034 CNY t−1 %COD−1. These results demonstrate that the process is efficient and economically viable for EfOM removal to realize food-processing wastewater reuse. Full article
(This article belongs to the Special Issue Separation Techniques and Circular Economy)
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14 pages, 5701 KiB  
Article
Alleviating Ultrafiltration Membrane Fouling Caused by Effluent Organic Matter Using Pre-Ozonation: A Perspective of EEM and Molecular Weight Distribution
by Kuo Gao, Hong Yang, Haichen Liu and Bingzhi Dong
Membranes 2023, 13(4), 452; https://doi.org/10.3390/membranes13040452 - 21 Apr 2023
Cited by 8 | Viewed by 2247
Abstract
Wastewater reclamation has gradually become an important way to cope with the global water crisis. Ultrafiltration plays an imperative part as a safeguard for the aim but is often limited by membrane fouling. Effluent organic matter (EfOM) has been known to be a [...] Read more.
Wastewater reclamation has gradually become an important way to cope with the global water crisis. Ultrafiltration plays an imperative part as a safeguard for the aim but is often limited by membrane fouling. Effluent organic matter (EfOM) has been known to be a major foulant during ultrafiltration. Hence, the primary aim of this study was to investigate the effects of pre-ozonation on the membrane fouling caused by EfOM in secondary wastewater effluents. In addition, the physicochemical property changes of EfOM during pre-ozonation and the subsequent influence on membrane fouling were systemically investigated. The combined fouling model and the morphology of fouled membrane were adopted to scrutinize the fouling alleviation mechanism by pre-ozonation. It was found that membrane fouling by EfOM was dominated by hydraulically reversible fouling. In addition, an obvious fouling reduction was achieved by pre-ozonation with 1.0 mg O3/mg DOC. The resistance results showed that the normalized hydraulically reversible resistance was reduced by ~60%. The water quality analysis indicated that ozone degraded high molecular weight organics such as microbial metabolites and aromatic protein and medium molecular weight organics (humic acid-like) into smaller fractions and formed a looser fouling layer on the membrane surface. Furthermore, pre-ozonation made the cake layer foul towards pore blocking, thereby reducing fouling. In addition, there was a little degradation in the pollutant removal performance with pre-ozonation. The DOC removal rate decreased by more than 18%, while UV254 decreased by more than 20%. Full article
(This article belongs to the Topic Membrane Separation Technology Research)
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16 pages, 1948 KiB  
Article
Controls on Organic Matter Accumulation from an Upper Slope Section on the Early Cambrian Yangtze Platform, South China
by Gongjing Zhang, Daizhao Chen, Yi Ding and Taiyu Huang
Minerals 2023, 13(2), 260; https://doi.org/10.3390/min13020260 - 12 Feb 2023
Cited by 5 | Viewed by 2255
Abstract
The early Cambrian witnessed profound environmental changes and biological evolution in Earth’ history. During this period, organic-rich shales were widely distributed over almost the entire Yangtze Block. However, the dominant factor that drove the significant accumulation of organic matter (OM) remains controversial and [...] Read more.
The early Cambrian witnessed profound environmental changes and biological evolution in Earth’ history. During this period, organic-rich shales were widely distributed over almost the entire Yangtze Block. However, the dominant factor that drove the significant accumulation of organic matter (OM) remains controversial and is still debated. Here, we analyzed TOC, organic carbon isotopes, iron speciation, major and trace elements for the lower Cambrian Niutitang Formation in the upper slope Meiziwan section, to investigate the dominant factor controlling OM accumulation. High contents of TOC and Baxs reveal an OM-enriched feature of the Niutitang Formation, and the coupled relationship between them suggest a strong production control on OM accumulation at Meiziwan. Meanwhile, negative relationships between TOC and chemical index of alteration (CIA) values as well as Al contents suggest that influence of chemical weathering and terrestrial input on OM accumulation were limited. Fairly low CoEF × MnEF values provide strong evidence that the deposition of organic-rich shales was under the control of oceanic upwelling event. The upwelling event would bring nutrient-rich deep waters into surface water, stimulating phytoplankton bloom and primary productivity in surface water and facilitating OM enrichment. Meanwhile, enhanced accumulation of OM would have promoted subsequent bacterial sulfate reduction, leading to the occurrence of occasional euxinia (evidenced by iron speciation and redox-sensitive trace element data) and promoting preservation of OM. Taken together, our results shed light on the critical role of oceanic upwelling on the marine primary productivity on the earliest Cambrian Yangtze Platform. Full article
(This article belongs to the Special Issue Reservoir and Geochemistry Characteristics of Black Shale)
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17 pages, 3560 KiB  
Article
Extraordinarily High Organic Matter Enrichment in Upper Permian Wujiaping Formation in the Kaijiang-Liangping Trough, Sichuan Basin
by Yao Du, Xingzhi Wang, Ruifeng Tang, Yiqing Zhu, Cong Yang, Hongfei Zhou and Qian Pang
Energies 2023, 16(1), 349; https://doi.org/10.3390/en16010349 - 28 Dec 2022
Cited by 7 | Viewed by 1886
Abstract
The study of extraordinarily high organic matter content (EHOMC) is beneficial to promote the fine evaluation of shale oil and gas, but so far, there have been few studies on its mechanism. This paper carried out a comprehensive lithological and geochemical analysis of [...] Read more.
The study of extraordinarily high organic matter content (EHOMC) is beneficial to promote the fine evaluation of shale oil and gas, but so far, there have been few studies on its mechanism. This paper carried out a comprehensive lithological and geochemical analysis of the black shales of the Wujiaping Formation in the Kaijiang-Liangping Trough. The results showed that the black shales of the Wujiaping Formation can be divided into two units (the upper and lower parts), and EHOMC occurs in its upper part. The redox-sensitive trace elements (RSTEs), MoEF-UEF covariation, and Ni/Co correlation showed that the lower part of Wujiaping Formation was a weakly restricted oxidation environment, while the upper part evolved into a sulfidation reducing environment. The productivity indicator elements (BaXS, NiXS, CuXS, P, and Mo) indicated that the upper Wujiaping Formation had higher primary productivity than the lower part. However, rare earth elements ((La/Yb)N) indicated that the deposition rate in the lower part of the Wujiaping Formation was higher than that in the upper part. In general, although the oxygenated water in the lower part of the Wujiaping Formation is not conducive to the preservation of organic matter, the high input of nutrients from land sources and the high deposition rate inhibit the decomposition of organic matter, so the lower part has a certain degree of organic matter accumulation. The sulfidation reducing environment and high paleoproductivity are the main reasons for the enrichment of organic matter in the upper part of the Wujiaping Formation. In addition, the sulfidation reducing environment and high paleoproductivity occurred during the violent upwelling at the end of Guadeloupe, a period of high sea level, these factors have jointly contributed to the enrichment of OM in the upper the Wujiaping Formation. Full article
(This article belongs to the Special Issue Advances in Petroleum Geology and Unconventional Oil and Gas)
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16 pages, 1084 KiB  
Article
Effects of Salinity on Abiotic Aggregation of Organic Matter and Subsequent Microbial Responses
by Tzong-Yueh Chen and Annelie Skoog
Gels 2022, 8(12), 836; https://doi.org/10.3390/gels8120836 - 18 Dec 2022
Cited by 2 | Viewed by 1614
Abstract
Studies of marine aggregation have focused on determining formation rates of larger particles from small particles. However, it has been shown that particles can form from the dissolved phase, which includes colloidal material. The purpose of this study was to investigate the effect [...] Read more.
Studies of marine aggregation have focused on determining formation rates of larger particles from small particles. However, it has been shown that particles can form from the dissolved phase, which includes colloidal material. The purpose of this study was to investigate the effect of aggregation on the chemical composition of both the dissolved and particulate phases in two salinity regimes: (1) the coast of Avery Point, Connecticut, USA (AP; salinity of 30.1 psu); (2) the estuary of Thames River, Connecticut, USA (TR; salinity of 5.0 psu). The samples were incubated on a roller table for two days in the dark at a speed of 8 rpm. The mixed collision mechanism of shear and differential sedimentation provided by the roller table enhanced the gross aggregation of particulate organic carbon (POC; 0.75 µM d−1 and 1.04 µM d−1 in AP and TR, respectively). Subsequent microbial degradation led to a negative net aggregation of POC (−5.20 µM d−1 and −1.19 µM d−1 in AP and TR, respectively). Although bacterial abundance remained in a narrow range in this study, the aggregation of organic matter (OM) enhanced planktonic community respiration (CR; CR increased 5.1 mg-C m−3 d−1 and 205.4 mg-C m−3 d−1 in AP and TR, respectively). The collision also led to a gross aggregation of uncharacterized particulate organic matter (POM) transferred from uncharacterized dissolved organic matter (DOM; 0.62 µM-C d−1 and 0.56 µM-C d−1 in AP and TR, respectively). The aggregated, uncharacterized POM could be biologically refractory. The C- and N-yields and enrichment factor (EF) analysis indicated that the organic substrate dynamics in this study were complicated. Full article
(This article belongs to the Special Issue Advanced Research of Aquatic Gels and Their Applications)
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16 pages, 361 KiB  
Article
Distributed Energy as a Megatrend of Audit of Investment Processes of the Energy Complex
by Natalie Gryzunova, Kirill Vedenyev, Victoria Manuylenko, Igor Keri and Michał Bilczak
Energies 2022, 15(23), 9225; https://doi.org/10.3390/en15239225 - 5 Dec 2022
Cited by 5 | Viewed by 1950
Abstract
The global trend is constantly increasing investments in strategic sectors of the economy, for example the electric power industry, which, in many countries, is becoming diversified and dispersed due to the multitude of entities investing in energy production and renewable resources, which leads [...] Read more.
The global trend is constantly increasing investments in strategic sectors of the economy, for example the electric power industry, which, in many countries, is becoming diversified and dispersed due to the multitude of entities investing in energy production and renewable resources, which leads to an increase in the heterogeneity of investment decisions. There is an urgent need to control the movement of investments, budget funds, as well as their development in the process of implementing investment programs of energy companies. The control of the movement of investments is the most promising direction of studying the subject of finance and audit. The increasing volume of public and private targeted investments in the energy sector and the lack of control over the effectiveness of investment projects (since each program contains several thousand lists of projects) necessitated the introduction of additional regulation of budget spending. The development of a mathematical apparatus for such regulation led to the creation in the Russian Federation of an institute of an independent public technological and price audit (TPA). The TPA is seen as a mechanism to ensure an effective project evaluation and selection process. This article describes methodological improvements using power system optimization models. The Integrated MARKAL-EFOM System (TIMES) was developed as part of the Energy Technology Systems Analysis Program of the IEA-ETSAP, an international community that uses long-term energy scenarios to conduct in-depth energy and environmental analyzes. This approach includes two different but complementary systematic approaches to energy modeling: an engineering approach and an economic approach. The same approach is used when conducting a TSA, when an investment object is evaluated as a set of technological and price parameters. The article considers a model of resource allocation in the energy sector and a mechanism for using TPA for investment projects with state participation in a natural monopoly. An approach to the financial and long-term distribution of investments of electric power companies based on the search for a balance of interests of the supplier and consumer and available energy sources is proposed. A model has been developed to find the optimal plan of technical solutions, taking into account the balance of the possibilities of the electric power industry and the needs of the economy. The relevance of the article is due to the requirements of investment efficiency, since the prevailing share in the costs is occupied by the costs of equipment and the construction of power plants. Full article
(This article belongs to the Special Issue Innovative Economic Technologies and Policies in the Energy Sector)
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