Search Results (175)

The surface of the Great Wall harbors a large number of non-vascular plants dominated by cyanobacteria, lichens and mosses as well as microorganisms, and form biocrusts by cementing with the soils and greatly alters the pore structure of the soil and the ecohydrological processes associated with the soil pore space, and thus influences the soil resistance to erosion. However, the microscopic role of the biocrusts in influencing the pore structure of the surface of the Great Wall is not clear. This study chose the Warring States Qin Great Wall in Weiyuan, Gansu Province, China, as research site to quantify thepore structure characteristics of the three-dimensional of bare soil, cyanobacterial-lichen crusts, and moss crusts at the depth of 0–50 mm, by using optical microscopy, scanning electron microscopy, and X-ray computed tomography and image analysis, and the precipitation infiltration process. The results showed that the moss crust layer was dominated by large pores with long extension and good connectivity, which provided preferential seepage channels for precipitation infiltration, while the connectivity between the cyanobacterial-lichen crust voids was poor; The porosity of the cyanobacterial-lichen crust and the moss crust was 500% and 903.27% higher than that of the bare soil, respectively. The porosity of the subsurface layer of cyanobacterial-lichen crust and moss crust was significantly lower than that of the biocrusts layer by 92.54% and 97.96%, respectively, and the porosity of the moss crust was significantly higher than that of the cyanobacterial-lichen crust in the same layer; Cyanobacterial-lichen crusts increased the degree of anisotropy, mean tortuosity, moss crust reduced the degree of anisotropy, mean tortuosity. Biocrusts increased the fractal dimension and Euler number of pores. Compared with bare soil, moss crust and cyanobacterial-lichen crust increased the isolated porosity by 2555% and 4085%, respectively; Biocrusts increased the complexity of the pore network models; The initial infiltration rate, stable infiltration rate, average infiltration rate, and the total amount of infiltration of moss crusted soil was 2.26 and 3.12 times, 1.07 and 1.63 times, respectively, higher than that of the cyanobacterial-lichen crusts and the bare soil, by 1.53 and 2.33 times, and 1.13 and 2.08 times, respectively; CT porosity and clay content are significantly positively correlated with initial soil infiltration rate (|r| ≥ 0.85), while soil type and organic matter content are negatively correlated with initial soil infiltration rate. The soil type and bulk density are directly positively and negatively correlated with CT porosity, respectively (|r| ≥ 0.52). There is a significant negative correlation between soil clay content and porosity Full article

A novel actinobacterial strain, designated E54^T, was isolated from a hyper-arid desert soil sample collected from the Kumtagh Desert in Dunhuang, Gansu Province, China. Phylogenetic analysis based on 16S rRNA gene sequences placed strain E54^T within the genus Lentzea, showing highest similarity to Lentzea waywayandensis DSM 44232^T (98.9%) and Lentzea flava NBRC 15743^T (98.5%). However, whole-genome comparisons revealed that the average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between E54^T and these related strains were below the thresholds for species delineation. Strain E54^T exhibited typical morphological characteristics of the genus Lentzea, forming a branched substrate. It grew optimally at 28–30 °C, pH 7.0–9.0, and tolerated up to 10% NaCl. The cell wall contained meso-diaminopimelic acid, the predominant menaquinone was MK-9(H₄), and major fatty acids included iso-C_16:0. The polar lipid profile comprised diphosphatidyl glycerol, phosphatidyl ethanolamine, phosphatidyl inositol, hydroxyphosphatidyl ethanolamine, and an unidentified lipid. The characteristic amino acid type of the cell wall was meso-DAP. Whole-cell hydrolysis experiments revealed the characteristic cell wall sugar fractions: ribose and galactose. The genome of strain E54^T is approximately 8.0 Mb with a DNA G+C content of 69.38 mol%. Genome mining revealed 39 biosynthetic gene clusters (BGCs), including non-ribosomal peptide synthetases (NRPS), polyketide synthases (PKS), terpenes, and siderophores. Comparative antiSMASH-based genome analysis across 38 Lentzea strains further demonstrated the genus’ remarkable biosynthetic diversity. NRPS and type I PKS (T1PKS) were the most prevalent BGC types, indicating a capacity to synthesize structurally complex and pharmacologically relevant metabolites. Together, these findings underscore the untapped biosynthetic potential of the genus Lentzea and support the proposal of strain E54^T as a novel species. The strain E54^T (=JCM 34936^T = GDMCC 4.216^T) should represent a novel species, for which the name Lentzea xerophila sp. nov. is proposed. Full article

Building upon the geological cycle theory, this study proposes fault cycles as a critical component of tectonic cyclicity in petroliferous basins. Focusing on reservoir-controlling faults in the southwestern Qaidam Basin, we systematically analyze fault architectures and identify three distinct fault activation episodes: the Lulehe Formation (LLH Fm.), the upper part of the Xiaganchaigou Formation (UXG Fm.), and the Shizigou Formation (SZG Fm.). Three types of fault cycle models are established. These fault cycles correlate with the evolution of regional tectonic stress fields, corresponding to the Cenozoic transition from extensional to compressional stress regimes in the basin. Mechanistic analysis reveals the hierarchical control of fault cycles in hydrocarbon systems: the early cycle governs the proto-basin geometry and low-amplitude structural trap development; the middle cycle affects the source rock distribution; and the late cycle controls trap finalization and hydrocarbon migration. This study proposes a fault cycle-controlled accumulation model, providing a dynamic perspective that shifts from conventional static fault concepts to reveal fault activity periodicity and its critical multi-phase control over hydrocarbon migration and accumulation, essential for exploration in multi-episodic fault provinces. Full article

As an important unconventional oil and gas resource, tight oil exploration and development is of great significance to ensure energy supply under the background of continuous growth of global energy demand. Low-porosity and low-permeability reservoirs are characterized by tight rock properties, poor physical properties, and complex pore structure, and as a result the fine calculation of logging reservoir parameters faces great challenges. In addition, the crude oil in this area has high viscosity, the formation water salinity is low, and the oil reservoir resistivity shows significant spatial variability in the horizontal direction, which further increases the difficulty of oil and water reservoir identification and affects the accuracy of oil saturation calculation. Targeting the above problems, the Nutcracker Optimization Algorithm (NOA) was used to optimize the hyperparameters of the random forest classification model, and then the optimal hyperparameters were input into the random forest model, and the conventional logging curve and oil test data were combined to identify and classify the reservoir fluids, with the final accuracy reaching 94.92%. Compared with the traditional Hingle map intersection method, the accuracy of this method is improved by 14.92%, which verifies the reliability of the model for fluid identification of low-porosity and low-permeability reservoirs in the research block and provides reference significance for the next oil test and production test layer in this block. Full article

In the operation of enhanced geothermal systems (EGSs), complex physical and chemical coupling processes, which are crucial for the efficient exploitation of geothermal energy, are involved. In situ studies of multi-fracture hot dry rocks (HDRs) face significant challenges, leading to a shortage of experimental data for verifying numerical simulations and supporting experimental techniques. In this paper, a multi-field coupling experimental simulation technique was designed for a multi-fracture geothermal reservoir. This technique enables the experimental investigation of the effects of fracture and reservoir characteristics, working fluid parameters, and wellbore arrangement on the multi-field coupling transport mechanism inside geothermal reservoirs during EGS operation. In addition, the practicability and reliability of the experimental technique were proved via a two-dimensional multi-fracture model. The experimental technique addresses a research gap in studying multi-fracture geothermal reservoirs and holds potential to promote substantial progress in geothermal resource exploitation. Full article

The desert-steppe transition zone at the southern edge of the Hobq Desert features complex topography and frequent wind/sand activities. To explore the impact of different underlying surfaces and topography on the wind-sand environment in this area, field measurements were conducted to analyze the temporal and spatial variations of sand-moving wind conditions and sand drift potential. The results indicate that the average wind speed, sand-moving wind frequency, sand drift potential and sand transport rate in this area were higher in spring and winter than in summer and fall temporally. Spatially, different underlying surfaces and topographic conditions, the characteristics of the average wind speed, sand-moving wind frequency, sand drift potential and sand transport rate were as follows: quicksand surface > grassland surface > shrub surface, and top of slope > quicksand surface > middle of slope. The predominant annual wind directions and sand-moving wind directions were W, WNW and NW. The sand drift direction was towards the E or ESE in winter and spring. This study provides a theoretical basis and scientific support for the development of targeted sand control measures in the desert-steppe transition zone at the southern edge of the Hobq Desert, thereby maintaining regional ecological sustainability. Full article

The use of Reclaimed Asphalt Pavement (RAP) is a sustainable strategy to conserve natural resources, reduce environmental pollution, and lower construction costs. However, aged asphalt in RAP suffers from oxidation and loss of light fractions, increasing stiffness and brittleness. A key scientific challenge is how to effectively restore the performance of aged asphalt while maintaining cost efficiency. In this study, a novel asphalt rejuvenator was developed to address this issue. The rejuvenator consists of 6% aromatic oil-like materials to replenish light components, 1.52% plasticizer to enhance ductility, and 0.3% modifier A to improve adhesion, with a total dosage of 7.82% by the mass of the aged binder. The rejuvenator meets the requirements of Chinese specifications. The performance evaluation was conducted at both asphalt binder and mixture scales. The results show that the rejuvenator significantly improves low-temperature cracking resistance and medium-temperature fatigue performance of aged binders, although it slightly reduces high-temperature rutting resistance. When applied to asphalt mixtures with 45% RAP, the rejuvenated mixtures exhibited enhanced low-temperature performance. A comparative analysis with commercial rejuvenators confirmed the developed product’s competitive performance and economic benefit. This study provides technical insight into rejuvenator design and addresses critical challenges in RAP recycling for sustainable pavement engineering. Full article

To promote the inheritance of traditional culture, a variety of emerging methods rooted in machine learning and deep learning have been introduced. Dunhuang patterns, an important part of traditional Chinese culture, are difficult to collect in large numbers due to their limited availability. However, existing text-to-image methods are computationally intensive and struggle to capture fine details and complex semantic relationships in text and images. To address these challenges, this paper proposes the Diffusion Adapter Network (DANet). It employs a lightweight adapter module to extract visual structural information, enabling the diffusion model to generate Dunhuang patterns with high accuracy, while eliminating the need for expensive fine-tuning of the original model. The attention adapter incorporates a multihead attention module (MHAM) to enhance image modality cues, allowing the model to focus more effectively on key information. A multiscale attention module (MSAM) is employed to capture features at different scales, thereby providing more precise generative guidance. In addition, an adaptive control mechanism (ACM) dynamically adjusts the guidance coefficients across feature layers to further enhance generation quality. In addition, incorporating a cross-entropy loss function enhances the model’s capability in semantic understanding and the classification of Dunhuang patterns. The DANet achieves state-of-the-art (SOTA) performance on the proposed Diversified Dunhuang Patterns Dataset (DDHP). Specifically, it attains a perceptual similarity score (LPIPS) of 0.498, a graph matching score (CLIP score) of 0.533, and a feature similarity score (CLIP-I) of 0.772. Full article

The conservation of cultural heritage requires advanced analytical tools to assess historic materials. In the context of the IPERION-CH project, a mobile multi-spectroscopic characterisation system for the analysis of cultural heritage materials, designated SYSPECTRAL, has been developed. This system integrates Laser-Induced Breakdown Spectroscopy (LIBS), Laser-Induced Fluorescence, Raman spectroscopy, and reflectance spectroscopy. The first application of SYSPECTRAL in a real-world setting was carried out at Müstair Monastery (UNESCO World Heritage Site since 1983) for wall paintings. In this study, stratigraphic analysis using LIBS revealed lead- and iron-based pigments in black and red hues, suggesting pigment degradation and restoration interventions. The presence of titanium in white hues indicated possible retouching. Furthermore, the presence of Egyptian blue in blue hues was identified through a combination of elemental and reflectance spectral analysis, underscoring the potential of SYSPECTRAL for heritage conservation. This approach offers comprehensive material characterization with minimal impact, a finding that is of particular significance in the context of heritage conservation. The subsequent phase of research will extend the application of SYSPECTRAL to a wider range of heritage sites, with the objective of enhancing the spectral databases and refining the analytical techniques for the purpose of improving cultural heritage conservation. Full article

Red lead (Pb₃O₄) has been extensively utilized as a red pigment for centuries. However, the discoloration and blackening of red lead in historical paintings have significantly compromised the aesthetic value of mural artworks. Investigating the mechanisms behind the blackening of Pb₃O₄ is of paramount importance. This study examined the effects of four kinds of reactive oxygen species (ROS) on the aging process of Pb₃O₄ in an alkaline environment. Specifically, singlet oxygen (¹O₂), superoxide radical (O₂⁻·), hydrogen peroxide (H₂O₂), or peroxynitrite (ONOO⁻) was individually reacted with Pb₃O₄. The resulting products were analyzed qualitatively and quantitatively using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS), Raman spectroscopy, inductively coupled plasma mass spectrometry (ICP-MS), and UV-Vis spectroscopy. The findings indicate that singlet oxygen (¹O₂) and superoxide radicals (O₂⁻·) effectively induce the aging of Pb₃O₄, whereas hydrogen peroxide (H₂O₂) and peroxynitrite (ONOO⁻) exhibit little impact on its aging. This research elucidates the aging mechanisms of Pb₃O₄ in alkaline environments and provides valuable insights for the preservation and restoration of mural paintings. Full article

The forecasting of high-water-cut oil well production faces challenges of strong nonlinearity and nonstationarity due to reservoir heterogeneity and multiscale dynamic characteristics. This study proposes a hybrid CEEMDAN-SR-BiLSTM framework based on a “decomposition-feature enhancement-integration” architecture. The framework employs Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) to suppress mode mixing, reconstructs high-, medium-, and low-frequency subsequences using Hilbert-Huang Transform (HHT) combined with tercile thresholding, and finally achieves multiscale feature fusion prediction through a Bayesian-optimized bidirectional long short-term memory network (BiLSTM). Interpretability analysis based on SHapley Additive exPlanations (SHAP) values reveals the contribution degrees of parameters such as water injection volume and flowing pressure to different frequency components, establishing a mapping between production data features and physical mechanisms of oil well production. This mapping, integrated with physical mechanisms including wellbore transient flow, injection-production response lag, and reservoir pressure evolution, enables mechanistic interpretation of production phenomena and quantitative decoupling and prediction of multiscale dynamics. Experimental results show that the framework achieves a root-mean-square error (RMSE) of 3.75 in forecasting a high-water-cut well (water cut = 87.6%) in the Qaidam Basin, reducing errors by 26.0% and 50.0% compared to CEEMDAN-BiLSTM and BiLSTM models, respectively, with a coefficient of determination (R²) reaching 0.954. Full article

The geographical origin identification of wolfberry is key to ensuring its medicinal and edible quality. To accurately identify the geographical origin, the Stacking-Orthogonal Linear Discriminant Analysis (OLDA) algorithm was proposed by combining OLDA with the Stacking ensemble learning framework. In this study, Savitzky–Golay (SG) + Multiplicative Scatter Correction (MSC) served as the optimal preprocessing method. Four classifiers—K-Nearest Neighbors (KNN), Decision Tree, Support Vector Machine (SVM), and Naive Bayes—were used to explore 12 stacked combinations on 400 samples from five regions in Gansu: Zhangye, Yumen, Wuwei, Baiyin, and Dunhuang. When Principal Component Analysis (PCA), PCA + Linear Discriminant Analysis (LDA), and OLDA were used for feature extraction, Stacking-OLDA achieved the highest average identification accuracy of 99%. The overall accuracy of stacked combinations was generally higher than that of single-classifier models. This study also assessed the role of different classifiers in different combinations, finding that Stacking-OLDA combined with KNN as the meta-classifier achieved the highest accuracy. Experimental results demonstrate that Stacking-OLDA has excellent classification performance, providing an effective approach for the accurate classification of wolfberry origins and offering an innovative solution for quality control in the food industry. Full article

This study explored the effect of compounding artificial hydraulic lime and silica fume for use as a sandstone grotto patching material. Different proportions of silica fume were added to hydraulic lime in lab tests, and their effects on the mortar’s physical and mechanical properties were studied. The results show that adding silica fume significantly increased the flexural and compressive strengths of the mortar and the shrinkage rate. A comparative analysis revealed that the comprehensive performance of the mortar reached the optimal state when the silica fume content was 10%. This met the strength requirements of repair materials for sandstone grottoes, as well as the control requirements regarding the shrinkage rate. Additionally, it demonstrated excellent weather resistance. This study’s results provide a scientific basis for the restoration of sandstone grottoes and the screening of an appropriate ratio of repair materials, which holds significant practical application value for the protection and reinforcement of stone relics. Full article

Traditional studies on Chinese Buddhism have largely relied on printed canons from the Song, Yuan, Ming, and Goryeo dynasties. However, recent discoveries of Dunhuang and Turfan manuscripts, along with growing recognition of Nihon kosha issaikyō (Japanese Ancient Manuscript Canons), have expanded the scope of Buddhist textual research. Despite their significance, Japanese manuscript Buddhist canons remain underexplored, particularly in relation to their textual lineages and connections to Tang-dynasty texts. This study examines Nihon kosha issaikyō through a philological analysis of the Shisong lü (Ten Recitation Vinaya), assessing textual variants, structural patterns, and transmission histories. By situating Nihon kosha issaikyō within the broader East Asian Buddhist tradition, this research clarifies their role in preserving alternative textual lineages beyond standardized printed canons. The findings contribute to a deeper understanding of Buddhist textual transmission, canon formation, and the interplay between manuscript and printed traditions in China, Korea, and Japan. This study highlights the historical processes that shaped East Asian Buddhist canons and offers new insights into their adaptation and preservation across different cultural contexts. Full article

This paper examines the Nanatsu-dera manuscript of the Dafangguang Rulai Xingqi Weimizang Jing (RXWJ) through the lens of scribal practices, with a focus on variant characters (yitizi, 異體字) and textual transmission. As a “separately produced scripture” (bie sheng jing, 別生經), the RXWJ was not included in the woodblock-printed editions of the Chinese Buddhist canon, which limited its circulation and made manuscript copies—such as the Nanatsu-dera manuscript—critical for reconstructing its textual evolution, transmission, and scribal modifications. A detailed paleographic investigation reveals scribal variants, orthographic fluidity, and phonetic substitutions, illustrating both intentional adaptations and unintentional errors in textual transmission. Comparative analysis with Dunhuang fragments and the Taishō Canon further contextualizes these variations, shedding light on the interpretive challenges scribes and readers face. The findings suggest that the Nanatsu-dera manuscript underwent three stages of transmission: (1) it originated from the Fifty-Fascicle edition circulating in China, (2) it was used as a base text (diben, 底本) for manuscript copying in Japan, and (3) it was subsequently re-copied and preliminarily collated by Japanese scribes. By tracing scribal variants and textual transmission through a paleographic approach, this research underscores the critical role of manuscript culture in preserving texts outside the canonical tradition, offering new insights into the mechanisms of Buddhist textual transmission and adaptation in medieval East Asia. Full article