Search Results (386)

With the increasing global demand for energy, the development of unconventional resources has become a focal point of research. Among these, shale gas has drawn considerable attention due to its abundant reserves. However, its low permeability and complex fracture networks present substantial challenges. This study investigates the composite fracturing technology combining supercritical CO₂ and slickwater for shale gas extraction, elucidating the mechanisms by which it influences shale fracture roughness and conductivity through an integrated approach of theory, experiments, and numerical modeling. Experimental results demonstrate that the surface roughness of shale fractures increases markedly after supercritical CO₂–slickwater treatment. Moreover, the dynamic evolution of permeability and porosity is governed by roughness strain, adsorption expansion, and corrosion compression strain. Based on fluid–solid coupling theory, a mathematical model was developed and validated via numerical simulations. Sensitivity analysis reveals that fracture density and permeability have a pronounced impact on shale gas field productivity, whereas fracture dip angle exerts a comparatively minor effect. The findings provide a theoretical basis for optimizing composite fracturing technology, thereby enhancing shale gas extraction efficiency and promoting effective resource utilization. Full article

The relentless pace of industrialisation and globalisation has precipitated the rapid depletion of surface mineral deposits, presenting a formidable challenge to conventional mining operations and exerting a detrimental impact on their profitability. This depletion, coupled with the escalating demand for minerals, has driven prices to unprecedented highs, thereby inflating operating costs across various industries. Traditional surface and underground mining methods, struggling to meet burgeoning demands, contribute significantly to environmental degradation and substantial energy consumption. In response to these challenges, this study advocates for a paradigm shift from conventional mining methods and mineral resources toward untapped alternatives that hold the potential for enhanced economic viability and sustainability. Utilising environmentally friendly techniques and adopting more economical approaches becomes paramount in addressing the pressing demands of the current era and securing resources for future generations. This short review examines potential alternative mineral resources and the associated mining methods, including fluidised mining, deep-sea mining, brine mining, urban mining, in-situ and heap leaching, and space mining. A meticulous evaluation of the state-of-the-art technologies developed for these unconventional methods is conducted, including an assessment of their respective advantages and disadvantages. Finally, the study deliberates on the prospects of each approach, elucidating their potential contributions to alleviating the global metal crisis. This research provides insights that can inform sustainable mining practices and guide the industry toward a more environmentally responsible and economically viable future. The urgency of such a transition is underscored by the need to address the challenges posed by conventional mining and ensure the availability of mineral resources for generations to come. Full article

The flash vacuum expansion (FVE) process is an unconventional technology that enables the generation of fruit purees by altering the state of the water stored in the vacuoles. The plant tissue is subjected to an increase in temperature (from 25 to 54 °C) while maintaining a constant pressure (101.3 kPa). The temperature and pressure are then rapidly reduced (25 °C and 5 kPa, respectively). This promotes the conversion of water from liquid to gas, increasing its volume, which causes cell rupture and efficiently releases cellular components, including compounds stored in the vacuole. Furthermore, fermentation with lactic acid bacteria (LAB) is a biotechnological strategy that allows the generation of beverages with specific characteristics derived from the metabolism of LAB. LAB are capable of consuming sugars as an energy source and producing organic acids as a means of defense against microbial competitors. This research analyzes the effect of the FVE process and the genetics of Limosilactobacillus fermentum J24 on sugars and organic acids in a papaya-based beverage. During the production of papaya puree, FVE affects the concentration of sugars and organic acids, leading the bacteria to a different metabolic response than when FVE is not used for papaya puree production. Limosilactobacillus fermentum J24 was found to activate genes that confer high potential for use in the fermentation of plant-based matrices, although it was isolated from cheese. Full article

This paper presents a comparative study on the transdisciplinary design of resilient urban subcenters, examining the interplay between human-led and artificial intelligence (AI)-generated design approaches. By employing holistic design methods, we prepare and present revitalization projects for two areas of urban space. Our goal was to create a resilient urban subcenter that contributes to the development of a resident. The first revitalized site reflects the multicultural past of the city. The second project addresses the need to revitalize a subcenter reserved for residents. In the non-AI approach, holistic design is implemented across various universities, fields, and academic disciplines—the humanities, social sciences, engineering, and the arts. Transdisciplinary teams of sociologists, engineers, interior designers, architects, urban geographers, and acousticians transcend workshop limitations as well as cognitive boundaries, promoting the creation of new, unconventional knowledge. The AI-integrated approach employs artificial intelligence in a dual capacity: both as a generator of alternative design visions and as an analytical tool for assessing technological readiness. The findings contribute to the evolving discourse on sustainable urban development and the transformative potential of technology in transdisciplinary design practices. Full article

Unconventional yeasts, most notably those belonging to the genus Yarrowia, are garnering mounting interest from the scientific community due to their considerable promise in biotechnological applications. In the scientific literature, most attention is devoted to the species Y. lipolytica. The present work focuses on presenting the detailed phenotypic and metabolic characteristics of other less studied species, such as Y. bubula, Y. deformans, Y. phangngensis, and Y. alimentaria. The review includes a comprehensive analysis of Yarrowia species, focusing on their taxonomy, ecology, physiology, and industrial potential. These yeasts demonstrate significant variability in terms of temperature tolerance, substrate utilization, enzymatic activity, and lipid accumulation. A comparative analysis of strain collections, genomic features, and published biochemical studies is conducted. Several described species possess characteristics that are suitable for many applications, including protease production, adaptation to low temperatures, and synthesis of valuable lipids and sugar alcohols. This review also presents a regulatory framework supporting the safe use of Yarrowia yeast species in food, feed, and pharmaceuticals, and discusses the genetic background of those microorganisms. Although Y. lipolytica is the most prevalent species in current applications, the growing knowledge of other Yarrowia species suggests significant untapped potential. It is imperative that further comparative, safety application, and genomic studies be conducted in order to fully exploit this diversity for the purpose of sustainable biotechnological innovation. Full article

The landscape of marketing is rapidly evolving as companies adapt to new societal dynamics and technological advancements. Guerrilla marketing, characterized by its unconventional, creative, and cost-effective tactics, has proven effective in capturing consumer attention. When integrated with social media platforms, these tactics gain amplified reach, immediacy, and interactive potential, fostering viral spread and deeper consumer engagement. This research seeks to answer the pivotal question: “How does guerrilla marketing on social media influence consumer behavior and brand awareness?” To address this, a comprehensive literature review was conducted to provide an in-depth analysis of relevant studies in the field. Our findings reveal that this integration significantly enhances consumer engagement, boosts brand awareness, and positively influences purchasing behavior. Moreover, it provides firms with competitive advantages in dynamic, resource-constrained markets. The results highlight the importance of leveraging creative marketing approaches alongside digital platforms to shape consumer choices and drive successful marketing outcomes in the digital age. Full article

Hydraulic fracturing is a core stimulation technology for enhancing hydrocarbon production. However, it faces significant technical bottlenecks in unconventional reservoirs. These bottlenecks include poor adaptability to high-temperature and high-salinity environments, water-sensitive formation damage, and insufficient long-term fracture conductivity. Nanotechnology leverages unique properties of nanomaterials, such as surface effects, quantum size effects, and designability. Nanotechnology offers systematic solutions for optimizing fracturing fluids, enhancing proppant performance, and innovating waterless fracturing techniques. This review outlines the current status of fracturing technology, exploring the role of nanoparticles in improving fluid rheology, proppant strength, and interface regulation, and discusses future challenges. Studies show that nanomodified fracturing fluids can increase high-temperature viscosity retention by over 300%. Meanwhile, waterless fracturing reduces water consumption by 80%. Despite challenges in particle agglomeration and cost, nanotechnology demonstrates significant potential in boosting recovery and reducing environmental impact. Nanotechnology is positioned as a transformative technology for future unconventional resource development. Full article

Advancements in material science have allowed us to exploit the potential of new era for aircraft production. High-performance composites and alloys have allowed us to improve the performance and durability of aircraft, but they have become more and more precious with time. These materials can provide significant advantages in use but are costly, energy-intensive to produce, and their recovery and reuse has become a critical step to be addressed. Accordingly, a new approach in which end-of-life aircrafts represent unconventional mines rather than a disposal challenge is becoming increasingly relevant, providing access to high-value strategic raw materials and aligning with circular economy principles including European Green Deal and the United Nations Sustainable Development Goals. The complexity of dismantling and processing hybrid structures composed of metal alloys, ceramics, and advanced composites requires multiple approaches able to integrate chemical, mechanical, and thermal recovery routes. Accordingly, this review critically discusses the state of the art of the routes of end-of-life aircraft treatments, evaluating the connections between technology and regulation, and positions material recycling and reuse as central pillars for advancing sustainability in aerospace. Furthermore, this review provides a comprehensive reference for addressing the technical, economic, and policy challenges of waste management in aviation, contributing to broader goals of resource circularity and environmental preservation set forth by international sustainability agendas. Full article

Limited-Entry Liner (LEL) technology has emerged as a transformative solution for enhancing hydrocarbon recovery in unconventional reservoirs while addressing challenges in carbon sequestration. This review examines the role of LEL in optimizing acid stimulation, hydraulic fracturing and production optimization, focusing on its ability to improve fluid distribution uniformity in horizontal wells through precision-engineered orifices. By integrating theoretical models, experimental studies, and field applications, we highlight LEL’s potential to mitigate the heel–toe effect and reservoir heterogeneity, thereby maximizing stimulation efficiency. Based on a comprehensive review of existing literature, this study identifies critical limitations in current LEL models—such as oversimplified annular flow dynamics, semi-empirical treatment of wormhole propagation, and a lack of quantitative design guidance—and aims to bridge these gaps through integrated multiphysics modeling and machine learning-driven optimization. Furthermore, we explore its adaptability for controlled CO₂ injection in geological storage, offering a sustainable approach to energy transition. This work provides a comprehensive yet accessible overview of LEL’s significance in both energy production and environmental sustainability. Full article

Tight gas reservoirs, as important unconventional natural gas resources, face low recovery rates due to low porosity, low permeability, and strong heterogeneity. CO₂ Storage with Enhanced Gas Recovery (CSEGR) technology combines CO₂ geological storage with natural gas development, providing both economic and environmental benefits. However, the main controlling factors and influence mechanisms remain unclear. This study utilized the PR-EOS to investigate CH₄, CO₂, and natural gas physical properties, established a numerical simulation model considering CO₂ dissolution and geochemical reactions, and explored the influence of injection scheme, injection rate, production rate, and shut-in condition on CO₂ enhanced recovery and storage effectiveness through orthogonal design. Results show that CO₂ exhibits significant differences in compressibility factor, density, and viscosity compared to natural gas, enabling piston-like displacement. Intermittent injection slightly outperforms continuous injection in recovery enhancement, while continuous injection provides greater CO₂ storage capacity. The ranking of the significance of different influencing factors for enhanced oil recovery is as follows: injection rate > production rate > injection scheme > shut-in condition. For the effect of geological storage of CO₂, it is as follows: injection rate > injection scheme > production rate > shut-in condition. During gas injection, supercritical, ionic, and dissolved CO₂ continuously increase while mineral CO₂ decreases, with storage mechanisms dominated by structural and residual trapping. The study provides scientific basis for optimizing CO₂ flooding strategies in tight gas reservoirs. Full article

The role of green and low-carbon energy (gLE) resources in realizing the envisaged future decarbonized energy generation and supply cannot be overemphasized. The world has witnessed growing attention to the application of green energy (gE) sources such as solar, wind, hydro, geothermal, and biomass (energy crops, biogas, biodiesel, etc.). There is also the existence of low-carbon energy (LE) resources such as power-to-X, power-to-fuel, power-to-gas, e-fuel, waste-to-energy, etc., which possess huge potential for delivering sustainable energy, thus facilitating a pathway for achieving the desired environmental sustainability. In addition, the evolution of the cyber-physical power systems and the need for strengthening capacity in advanced energy materials are among the key factors that drive the deployment of gLE technologies around the world. This paper, therefore, presents the recent global developments in gLE resources, including the trends in their deployments for different applications in commercial premises. The study introduces different conceptual technical models and configurations of energy systems; the potential of multi-energy generation in a microgrid (m-grd) based on the gLE resources is also explored using the System Advisor Model (SAM) software. The m-grd is being fueled by solar, wind, and fuel cell resources for supplying a commercial load. The quantity of carbon emissions avoided by the m-grd is evaluated compared to a purely conventional m-grd system. The paper presents the cost of energy and the net present cost of the proposed m-grid; it also discusses the relevance of carbon capture and storage and carbon sequestration technologies. The paper provides deeper insights into the understanding of clean and unconventional energy resources. Full article

This study addresses the key technical challenges in monitoring hydraulic fracturing within unconventional reservoirs through an innovative wide-field electromagnetic (WEM) monitoring technique. The method employs a 5A AC-excited wellbore-fracturing fluid system to establish a conductor antenna effect, coupled with a surface electrode array (100–250 m offset) to detect millivolt-level time-lapse potential anomalies, enabling real-time dynamic monitoring of 142 fracturing stages. A line current source integral model was developed to achieve quantitative fracture network inversion with less than 12% error, attaining 10 m spatial resolution and dynamic updates every 10 min (80% faster than conventional methods). Optimal engineering parameters were identified, including fluid intensity ranges of 25–30 m³/m for tight sandstone and 30–35 m³/m for shale, with particulate diverters achieving 93.1% diversion efficiency (significantly outperforming chemical diverters at 35%). Application in deep reservoirs maintained signal attenuation rates below 5% per kilometer. Theoretically, a nonlinear relationship model between fluid intensity and stimulated area was established, while practical implementation through real-time adjustments in 142 stages enhanced single-well production by 15–20% and reduced diverter costs, advancing the paradigm shift from empirical to scientific fracturing in unconventional reservoir development. Full article

The contemporary world places a high degree of focus on the sustainable development of energy, with technological innovation in unconventional energy becoming a key driver of the global energy revolution. From a network analysis perspective, this paper constructs a patent citation network for unconventional energy technologies to empirically investigate the environmental impact of their influence. This study finds that an increase in the influence of domestic unconventional energy technology patents can reduce the embodied energy intensity of industries, but it also exhibits an energy rebound effect, which in turn promotes industrial carbon emissions. Citing foreign patented technologies does not significantly improve the environmental problems faced by domestic industries; on the contrary, it increases industrial greenhouse gas emissions. However, international energy technology cooperation can partially mitigate this negative impact. In response, this study recommends strengthening diversified investment in and cross-industry application of unconventional energy technologies, enhance international cooperation and policy coordination, focus on balancing the conflict between technological innovation and environmental goals, and maximize the environmental improvement potential of unconventional energy technologies. Full article

Shale gas wastewater from hydraulic fracturing poses significant environmental risks due to its high salinity and complex inorganic composition. This study investigates the behavior of major and trace inorganic constituents across a full-scale treatment train in the Sichuan Basin, China. Despite multi-stage processes including equalization, flocculation, flotation, biological reactors, membrane filtration, and clarification, key inorganic species such as Cl, Na, Br, Sr, Li, and B remained largely persistent in the final effluent with values of 13,760, 8811, 70, 95.9, 26.6, and 60.2 mg/L, respectively. Geochemical tracers including Br/Cl (average: 0.0022 mM/mM), Na/Br (average: 125 mg/mg), and Sr/Ca (average: 0.15 mM/mM) ratios, combined with halide endmember mixing models, revealed that salinity primarily originated from highly evaporated formation brines, with limited evidence for halite dissolution or external contamination. Elevated Sr (average: 89.3 mg/L) and Ca (average: 274 mg/L) levels relative to Mg (average: 32 mg/L) suggest significant water–rock interaction. Environmental risk assessments showed that concentrations of several elements in treated effluent greatly exceeded national and international discharge or reuse standards. These findings underscore the limitations of conventional treatment technologies and highlight the urgent need for advanced processes and regulatory frameworks that address the unique challenges of high-TDS (total dissolved solids) unconventional wastewater. Full article

As high-end oil and gas equipment, the high-temperature high-pressure (HTHP) adaptability and intelligence level of Rotary Steerable Systems (RSS) directly determine the development efficiency of deep unconventional resources. This paper reviews the technological breakthroughs and industrial chain synergy pathways of domestic RSS in China, with core conclusions as follows: (1) domestic technologies represented by the CG STEER system have achieved stable operation at 150 °C, high build rates of 15.3°/30 m, and reservoir penetration rates of 98.7%, with key indicators reaching international advanced levels; (2) collaborative innovations in material system reconstruction, hybrid steering mechanisms, and vibration suppression technology have reduced single-well drilling cycles by 50%; (3) industrial chain synergy effects are significant: a 95% localization rate reduced the cost per bottom hole assembly (BHA) run to CNY 2 million, and the “Penta-Helix” innovation model increased patent sharing rates to >60%; (4) breakthroughs in 175 °C high-temperature chips and downhole intelligent decision-making algorithms are urgently needed. This study provides technological paradigms and industrial upgrading pathways for the autonomous development of drilling equipment for extreme conditions. Recognizing the need for comprehensive improvement, the revised manuscript will strengthen three key aspects: (1) supplementing systematic comparisons between domestic technologies and international benchmarks in terms of HTHP adaptability and intelligent control; (2) elaborating technical details of hybrid steering mechanisms and vibration suppression technologies to clarify their innovation in industrial processes; (3) adding case studies of autonomous decision-making systems in ultra-deep wells to verify the practical effectiveness of the proposed methods. These revisions aim to address the current limitations and enhance the scientific rigor of the study. Full article