Search Results (1,169)

From the perspective of coordinating development and security for high-quality development in border regions, this paper focuses on the adaptation relationship between development and security functions in the Yunnan–Guangxi border region. The study aims to characterize the spatiotemporal evolution and spatial differentiation of these two functions and identify distinct types of functional adaptation and their spatial characteristics. Based on the development–security linkage perspective, a regional functional evaluation system incorporating specialized indicators, such as border trade development and national territorial security, is constructed. The CRITIC method, a functional adaptation model, and spatial statistical methods are then employed to examine the spatiotemporal evolution of the development and security functions and their adaptation in the Yunnan–Guangxi border region from 2002 to 2022, followed by a classification of regional functional adaptation types. By integrating development and security functions into a unified analytical framework, this study extends the research perspective on regional functions and the development–security relationship in border areas and provides a reference for coordinating development and security and implementing differentiated spatial governance. The results indicate the following: ① The overall regional functional level of the Yunnan–Guangxi border region increased steadily, although the growth was characterized by distinct stages, with rapid growth in the early period followed by stabilization in the later period. Regional disparities first narrowed and then widened. Both the development and security functions increased from low to medium or high levels. Specifically, high-value areas of the development function were concentrated in inland hub cities, whereas those of the security function were distributed along the border. ② The overall adaptation between the development and security functions was favorable, with the adaptation index increasing slightly. The adaptation level in the Guangxi border region was higher than that in Yunnan, while the spatial distribution of adaptation types shifted from relative clustering to dispersion. ③ The county-level administrative units in the Yunnan–Guangxi border region were classified into five functional adaptation types. During the study period, the transitional upgrading type accounted for the largest proportion, and the overall spatial pattern was characterized by “advancement along the border while maintaining stability in the hinterland.” Therefore, differentiated guidance and governance strategies should be implemented according to the characteristics of each functional adaptation type to promote the dynamic coordination between development and security functions, thereby supporting spatial governance and functional improvement in border regions. Full article

Against the dual background of ICH (intangible cultural heritage) revitalization and urban stock space renewal, the renovation of traditional craft workshops has shifted from limited workshop repair to comprehensive space creation that balances craft protection, cultural dissemination, and sustainable operation. While existing scholarship has explored the functional composition and qualitative design strategies of ICH workshops, there remains a notable research gap in quantitative spatial performance evaluation frameworks tailored to craft production constraints, and the actual contribution of spatial design to living heritage transmission lacks objective measurement tools. This study takes craftsmanship-oriented ICH workshops as the core research object. Based on field investigations, multi-subject questionnaires, and expert consultations, 14 tertiary indicators are selected from three dimensions: production and safeguarding, experience and dissemination, and operation and development, to construct a spatial performance evaluation system for living heritage transmission. The Analytic Hierarchy Process (AHP) is adopted to determine the weight of each indicator. Taking the Yuezhou Fan ICH workshop as an empirical case, this study conducts a quantitative comparison of spatial performance before and after renovation. The results show that the comprehensive performance score of the workshop after renovation has increased by approximately 109.7% compared with that before renovation, among which the production and safeguarding dimension have the most significant improvement, verifying the rationality and practicability of the evaluation system. Theoretically, this study extends the application scope of built environment performance evaluation to the field of craft heritage spaces and establishes a closed-loop logic of “quantitative diagnosis—deficiency identification—targeted optimization” for workshop renovation. Based on the evaluation results, this paper proposes a progressive optimization path of “consolidating production baseline—upgrading experience scenarios—empowering diversified operation”, which provides a generalizable quantitative framework and practical reference for the spatial renovation and performance evaluation of similar craftsmanship-oriented ICH workshops. Full article

The rapid growth of rural e-commerce is reshaping rural development, yet its implications for territorial sustainability remain unclear. Using panel data from 1503 Chinese counties from 2014 to 2022, the effects of Taobao Village development and the mechanism of territorial sustainability are examined through causal, spatial, and mechanism analyses. The results show the following: (1) Taobao Village development significantly improves territorial sustainability, with stronger effects observed in central and northeastern China, while the impacts vary considerably across regions due to differences in economic foundations, digital infrastructure, and land-use conditions. (2) Spatial analysis reveals that the sustainability-enhancing effects of Taobao Villages are mainly localized, with no significant spillover effects to neighboring counties, indicating the constraints of existing administrative and spatial governance systems. (3) The ecological land-use change induced by Taobao Village development is characterized by quantity reduction with potential quality upgrading. The development of Taobao Village has reduced the ecological land area, but it does not mean a decline in ecological functions. The converted land may be composed of low-quality ecological plots, and the fiscal benefits driven by e-commerce and China’s land use compensation policy may maintain or enhance the overall ecological function. These findings highlight the importance of integrating digital rural development with ecological sustainability and territorial spatial governance. The study provides policy implications for promoting resilient and sustainable rural transformation through differentiated land-use strategies. Full article

Upgrading biogas to pipeline-quality methane requires the efficient removal of CO₂, yet conventional physicochemical routes remain energy-intensive. Coupling a CO₂-selective membrane with microalgal photosynthetic fixation offers a green alternative, but is constrained by the low CO₂/CH₄ selectivity of common membranes and the poor adhesion of microalgae to hydrophobic membrane surfaces. Here, a dual-functional composite membrane was developed that simultaneously provides CO₂/CH₄ sieving and a biocompatible interface for microalgal attachment, and was integrated into a microalgae membrane bioreactor (MMBR). A cellulose acetate mixed-matrix membrane incorporating polyethyleneimine-grafted ZIF-8 (CA/PZIF-8(15)) achieved a mixed-gas CO₂ permeability of 122.3 Barrer and a CO₂/CH₄ selectivity of 41.17. An ionic-liquid-modified chitosan (CS/IL) coating, first optimized on a commercial flat-sheet polyethersulfone (PES) membrane used as a model surface for the adhesion study, reversed the surface charge from −30.8 to +3.75 mV, lowered the water contact angle to 51.2°, and increased the day-7 adhesion of Scenedesmus obliquus by ~108%. Transferring the coating onto CA/PZIF-8(15) further raised the permeability to 138 Barrer and the selectivity to 57.31, placing the composite above the 2008 Robeson upper bound. In the MMBR, CH₄ purity reached 95.13% after 48 h; a mass balance on the recirculating gas volume indicated that essentially all of the CO₂ removed from the gas phase permeated the membrane, of which an estimated 2% was fixed into microalgal biomass while the remainder was retained in the liquid phase. This work offers a membrane-design strategy that bridges gas-separation functionality and microalgal carbon fixation for sustainable biogas upgrading. Full article

Against the dual background of restructuring global green trade rules and advancing China’s “dual-carbon” strategy, environmental information disclosure has increasingly become a crucial strategic tool for firms seeking to enhance international competitiveness. Existing studies have mainly examined the quantity, content, and quality of environmental information disclosure, while paying insufficient attention to its relative disclosure position, a strategic feature of information presentation that may affect signal salience and attention allocation. Drawing on signaling theory and the attention-allocation perspective, this study examines Chinese A-share listed exporters by matching environmental information disclosure positions observed during 2021–2023 with firms’ export product quality during 2022–2024. The final baseline sample contains 1472 firm-year observations. The findings show that earlier environmental information placement is significantly associated with higher subsequent export product quality. This relationship is mainly concentrated in the difference between Position_1 and Position_3, whereas Position_2 does not differ significantly from Position_1. The main result remains robust to alternative coding of disclosure position, additional controls for environmental disclosure volume, adjustment of the sample period, a panel-preserving placebo test, and an external peer-based instrumental-variable analysis. The three-step mechanism tests provide channel-consistent evidence for two potential transmission channels. More prominent environmental information placement is associated with a higher likelihood of ISO 14001 certification, reflecting stronger externally verifiable green credibility, and with greater realized green innovation output, reflected in granted green patents. Both mechanism variables are positively associated with subsequent export product quality. This study extends the literature on environmental information disclosure by shifting attention from static disclosure characteristics to the strategic prominence of information presentation, enriches the micro-level application of signaling theory in international trade, and provides practical insights for firms and regulators to improve the prominence, credibility, and substantive consistency of environmental disclosure while promoting export-quality upgrading. Full article

Nature-based solutions (NBSs) are central to urban climate-neutrality strategies, but their implementation still lags behind policy ambition. One reason is that most NBS benefits are public goods and rarely generate direct revenue, so we know far less about the institutional and financial conditions needed to deliver them than about their ecological performance. This paper develops a business model framework linking NBS interventions to financing and governance configurations, applying established NBS typologies and the Pestoff Triangle of state, market, and community provision to thirteen interventions across eleven sites in the Railway District of Thessaloniki, Greece. The interventions are organised into five business model categories: public space greening, private space upgrades, public–private hybrids, building retrofits, and renewable energy. Their financing logic is shaped less by intervention type than by ownership structure and stakeholder configuration. To address this gap, we followed category-specific blended finance strategies combining grants, private investment, regulatory incentives, and community resources, underpinned by stewardship-oriented governance. The findings suggest that scaling NBSs depends less on technical readiness than on institutional capacity to match financing and governance to local ownership and stakeholder contexts, offering a pathway from climate-neutrality strategy to implementable urban regeneration. Full article

Against the dual strategic backdrop of carbon peaking and carbon neutrality goals and high-quality urbanization development, extant literature exhibits four prominent research gaps: oversimplified evaluation indicator systems, exclusive exploration of the unidirectional carbon impacts exerted by urbanization, a scarcity of long-time-series coupling analyses targeting the Yangtze River Economic Belt (YEB), and functional fragmentation between coupling coordination assessment and predictive simulation tools. Drawing on panel data covering 11 provinces and municipalities within the YEB spanning 2000 to 2021, this study constructs a comprehensive urbanization evaluation framework encompassing four dimensions: population, economy, society, and spatial layout. Meanwhile, an integrated carbon emission assessment system is established from the perspectives of population, economy, energy consumption, and carbon sinks. The entropy-weight method is adopted to assign indicator weights, and a combination of the coupling coordination degree model and system dynamics (SD) model is employed to analyze spatiotemporal evolutionary characteristics and simulate development trends from 2022 to 2032. By organically integrating the coupling coordination model and the SD model, this study establishes an integrated analytical framework that unifies static comprehensive evaluation and driving-mechanism decomposition, thereby compensating for the limitations of time-series forecasting models such as the grey prediction model and ARIMA, which only fit trends from historical data. Empirical results reveal that regional urbanization levels witnessed sustained growth across 2000–2021, with spatial urbanization acting as the core driving pillar. The overall coupling coordination degree maintained a steady upward trajectory, while the east–west regional disparity gradually narrowed. The simulation projections for 2022–2032 demonstrate continuous improvements in coordinated development across the entire basin: the coupling coordination degree ranges from 0.788 to 0.954 for the eastern region, 0.810 to 0.859 for the central region, and 0.752 to 0.865 for the western region. Such spatial differentiation corresponds to distinct practical development pathways: low-carbon stock optimization in the east, low-carbon industrial undertaking in the central zone, and clean energy transition acceleration in the west. All provincial-level administrative regions are projected to achieve an upgrade in their coupling coordination grades by 2032. This study acknowledges several limitations: missing raw data are supplemented via interpolation, only a single baseline scenario is simulated, predictive uncertainty is not quantitatively measured, and subjectivity persists in the weight assignment of coupling subsystems. Ultimately, differentiated low-carbon urbanization governance strategies are proposed for the three sub-regions, offering empirical references for the coordinated realization of dual carbon targets throughout the Yangtze River basin. Full article

Social media is a vital platform for policy communication, yet research rarely integrates content and structural features to evaluate communication effects multidimensionally. This study proposes a convergent framework combining text mining and social network analysis to assess policy communication effects and underlying mechanisms. Using China’s upgraded Mass Entrepreneurship and Innovation policy on Sina Weibo as a case, we analyze communication breadth, depth, audience sentiment, thematic focus, network topology, key nodes, and community characteristics. The results reveal that (1) communication breadth is dominated by official communicators, while audiences drive interactive depth, reflecting a “centralized broadcasting, decentralized engagement” model; (2) influential users express more positive attitudes than ordinary audiences; (3) discussions diversify from core innovation themes to micro-level concerns like regional development and talent policies; (4) the network shows loose global structure but strong local clustering, with bridging nodes posting less polarized, broader content. Theoretically, this study offers behavioral-level observations that align with key corollaries of the Spiral of Silence Theory—the tendency for individuals with deviating views to shift toward lower-visibility participation. These pattern-level findings offer a complementary empirical perspective on opinion expression in digital policy contexts. Practically, the findings offer preliminary insights that may inform adaptive, decentralized strategies for enhancing policy diffusion in similar social media contexts. Full article

Methanol compression-ignition engines are vital for transport carbon neutrality, yet methanol’s low cetane number, corrosivity, low viscosity, and cavitation tendency compromised piezoelectric injector reliability. This study proposed systematic optimization strategies tailored to methanol’s fuel properties. A sealed thin-walled metal encapsulation, fabricated from precipitation-hardening martensitic stainless steel, was designed to isolate corrosive methanol media. The geometry of the tubular spring was optimized to meet the stiffness requirements for high-frequency injections. A monolithic nozzle without side pin holes, also upgraded to the same precipitation-hardening martensitic stainless steel, effectively suppressed stress corrosion cracking by leveraging the material’s combined high strength and excellent corrosion resistance. A dedicated return-line backpressure valve compensated for hydraulic leakage and improved fuel replenishment, and nozzle hole taper and inlet fillet radius were optimized to mitigate cavitation. Cold-motoring reliability tests showed the optimized injector maintained flow deviation within 3% after 100 million cycles, whereas the unoptimized prototype reached 8% deviation at 60 million cycles. The single-cycle injected fuel quantity coefficient of variation dropped from 4% to 1.3%. Spray characteristic comparison tests further confirmed that the optimized injector maintained stable flow consistency and atomization quality after prolonged cyclic operation. These optimizations effectively resolved corrosion, wear, and hydraulic instability caused by methanol, significantly enhancing flow consistency and durability over the service life. The results provided critical component-level technical support for advancing methanol compression-ignition engines from laboratory research to industrial application, addressing key reliability barriers that previously hindered engineering deployment of methanol-fueled powertrains. Full article

Horse manure is an abundant lignocellulosic feedstock with potential for circular biorefineries to diversify and upgrade the methane value chain. However, integrated fractionation strategies enabling the simultaneous valorization of both polysaccharides and lignin remain poorly explored. Here, we developed the Coffionic strategy, a closed-loop, green iono-organosolv fractionation combining, in a two-step, one-batch approach, the eco-acceptable ionic liquid 1-ethyl-3-methylimidazolium acetate and the food-grade solvent 2-methyltetrahydrofuran-3-one, with full solvent recovery and recycling. This strategy selectively recovered 70% w/w of the lignin from horse manure, yielding a Coffionic lignin fraction with a purity of 78% w/w and less than 2.5% w/w of residual sugars. The resulting polysaccharide-rich fraction showed enhanced enzymatic digestibility, achieving >99% cellulose conversion and increasing the biochemical methane potential by 17% compared with untreated horse manure. Coffionic lignin was further upgraded by enzymatic transesterification using immobilized Novozym435^® in the same food-grade solvent employed for fractionation, yielding lignin esters compatible with PLA. Esterified lignin–PLA films reached a total surface energy significantly higher than neat PLA and unmodified lignin–PLA films. Overall, the Coffionic strategy provides an integrated and low-waste biorefinery route enabling the simultaneous production of biomethane and high-value lignin-based materials from horse manure. Full article

Using panel data on Chinese A-share listed firms from 2002 to 2024, this study examines the impact of the Air Pollution Prevention and Control Action Plan (the Air Ten policy) on firms’ cross-regional investment. We identify the policy effect using a multi-period difference-in-differences (DID) model with firm and year fixed effects. The findings remain robust across a series of tests, including the parallel trend test, propensity score matching combined with DID (PSM-DID), placebo tests, alternative variable specifications, additional control variables, and high-dimensional fixed effects. The results show that the Air Ten policy significantly promotes firms’ cross-regional investment. Mechanism analyses suggest three potential channels through which the policy operates: enhancing firms’ green innovation capability, improving human capital quality, and facilitating regional industrial upgrading. The resulting industrial upgrading creates a more favorable external environment for firms to expand their investment activities. Heterogeneity analyses show that the positive effect is more pronounced among firms with higher R&D intensity, weaker internal control, and those located in eastern China. We find no evidence that the policy-induced cross-regional investment is driven by pollution relocation. Instead, the results suggest that firms’ cross-regional expansion is more likely to reflect a capability-driven mechanism than regulatory arbitrage. This finding is broadly consistent with the pollution halo perspective and provides further support for the Porter hypothesis. Overall, this study offers new insights into how environmental regulation reshapes corporate capital allocation and geographic expansion strategies. Full article

Pluvial flooding is intensifying in fast-growing coastal cities as rapid urbanization increases impervious surfaces and reduces natural infiltration, challenging planners to identify scalable and site-level mitigation strategies. Although statutory setbacks around institutional buildings are widely mandated for ventilation, safety, and accessibility, their contribution to urban flood resilience remains largely unexplored. This study develops the Flood Setback Performance Index (FSPI), a dimensionless indicator that integrates setback permeability and area-weighted runoff coefficients to quantify the flood-mitigation potential of mandatory setbacks. The framework was demonstrated using eight government school campuses in the Chennai, Chengalpattu, and Thiruvallur regions, which are part of a flood-prone coastal metropolis in India, following the extreme rainfall event of December 2025. Flood conditions were verified through post-event field surveys and visual evidence, while setback characteristics were extracted from satellite imagery and classified into permeable and impervious surfaces. The permeable fraction of setbacks and the FSPI values exhibited a strong inverse relationship with flood severity (Spearman’s ρ = −0.87, exact permutation p = 0.011). Ordinal logistic regression confirmed this gradient (likelihood-ratio χ² = 9.3–10.3, p ≤ 0.002, McFadden’s R² = 0.54–0.60), and campus rankings were made under saturated runoff coefficients. The findings demonstrate that statutory setbacks can function as nature-based flood-mitigation infrastructure with measurable hydrological benefits. Beyond the case study, the FSPI provides a simple, transferable, evidence-based tool for screening institutional sites by flood-mitigation performance and prioritizing where adaptation measures, such as increasing permeable-surface cover within statutory setbacks are needed, supporting climate-resilient urban planning and providing a regulatory reform decision-support tool with three applications: prioritizing the campus-level retrofit of permeable surfaces; screening building applications against setback surface standards; and identifying shelter-designated schools that require drainage upgrades. It thereby supports climate-resilient urban planning, regulatory reform, and progress toward Sustainable Development Goals 11 and 13. Full article

This study aims to reveal the formation mechanisms of typical defects in copper alloy castings and propose targeted process optimization strategies for production quality control. Taking the ZCuSn10P1 tin bronze outer layer of copper-clad iron core as the core research object, typical fracture and burr defects in actual mass production were systematically analyzed via multi-scale characterizations including SEM and EDS. Results show that fracture arises from abnormal Sn segregation and coarse hard-brittle δ phase, while burrs stem from insufficient matrix hardness during machining. Shrinkage cavity and porosity defects of aluminum bronze are further comparatively analyzed. A dual strategy of composition regulation and process optimization is put forward, which can effectively suppress defects and improve product qualification rate. This study provides a reliable reference for quality control and technical upgrading of copper alloy castings. Full article

The modernization of legacy industrial machines is a major challenge in intelligent automation, particularly when critical assets must be upgraded without replacing high-value mechanical and hydraulic infrastructure. This paper presents an industrial case study on the intelligent PLC-based retrofit of an obsolete Neyrpic Digipid speed governor installed in a Kaplan turbine. The proposed solution replaces a closed, vendor-dependent controller with an open Siemens ET 200SP architecture programmed in TIA Portal, integrating existing sensors, hydraulic actuators, redundant speed acquisition, sequential state-machine control, and a digital distributor–runner blade Cam Curve. A key technical contribution is the diagnosis and mitigation of hydraulic hunting in the distributor position loop. The instability was traced to the interaction between integral control action and the intrinsic integrating behavior of the hydraulic actuator, leading to the adoption of a proportional-only position tracking strategy. The system was validated through Factory Acceptance Tests (FATs) and Site Acceptance Tests (SATs), including signal verification, startup, synchronization, load acceptance and emergency load rejection. Quantitative results demonstrate that during initial commissioning of the new PLC-based PI position loop, the LVDT position error reached 41.59% peak-to-peak, with 351.2 servo-valve reversals per minute. Disabling the integral action reduced the peak-to-peak position error to below 1.5% and eliminated steady-state valve reversals under the tested operating conditions. Separately, the historical 0.966 V oscillation detected in the legacy analog-input chain was resolved during the retrofit. During no-load startup, the unit reached 97% of nominal speed in 49.4 s, with a maximum overshoot of 2.3% and a speed tracking standard deviation of 1.1%. The complete operational cycle was successfully validated under real industrial conditions, including a near-nominal load-rejection test (approximately 2.25 MW), during which the measured speed peaked at 126.4% of nominal speed and the shutdown sequence was completed without protection-system malfunction. The results show that open PLC-based retrofits can improve maintainability, diagnostics and operational reliability in safety-critical industrial machines, while establishing a foundation for future SCADA integration and condition-based maintenance. Full article

Against the backdrop of increasing renewable energy penetration, distribution networks face the dual challenges of spatiotemporal mismatch between sources and loads, as well as the surging costs of physical capacity expansion. To address these issues, this paper proposes a joint planning method for distribution network expansion and hybrid energy storage (electrical, thermal, and cooling) in green power parks, aimed at enhancing renewable energy accommodation. With the objective of minimizing the total life-cycle cost, a comprehensive optimization model integrating network topology upgrades and hybrid storage capacity configuration is established, which is then formulated and solved as a Mixed-Integer Linear Programming (MILP) problem. The effectiveness of the proposed strategy is validated through simulation comparisons with traditional solely line-based expansion schemes on the standard IEEE 33-bus system. The results indicate that substituting network expansion with energy storage can significantly alleviate the hardware investment burden on the grid. Moreover, leveraging the spatiotemporal “buffer” effect of multi-energy hybrid storage and the operation mechanism of cooling-heating-power substitution, surplus photovoltaic generation is efficiently absorbed locally, maintaining a renewable energy accommodation rate consistently above 50%. Economic evaluation further confirms that this joint planning framework reduces the total life-cycle cost by 21.2% compared to conventional transmission expansion approaches. It significantly enhances the system’s flexible bidirectional regulation capabilities, providing a solid theoretical foundation for the coordinated development of networks and storage in green power parks with high renewable energy penetration. Full article