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Influence of water coupling coefficient on the blasting effect of red sandstone specimens

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International Journal of Coal Science & Technology 2024年第1期11卷 148-166页

作者： Yang Li Renshu Yang Yanbing Wang Dairui Fu school of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China school of Civil and resource Engineering University of Science and Technology BeijingBeijing100083China

This study investigates the impact of different water coupling coefficients on the blasting effect of red *** analysis is based on the theories of detonation wave and elastic wave,focusing on the variation in wall pressure of the blasting *** DDNP explosive as the explosive load,blasting tests were conducted on red sandstone specimens with four different water coupling coefficients:1.20,1.33,1.50,and *** study examines the morphologies of the rock specimens after blasting under these different water coupling ***,the fractal dimensions of the surface cracks resulting from the blasting were calculated to provide a quantitative evaluation of the extent of rock *** scanning and 3D reconstruction were performed on the post-blasting specimens to visually depict the extent of damage and fractures within the ***,the volume fractal dimension and damage degree of the post-blasting specimens are *** findings are then combined with numerical simulation to facilitate auxiliary *** results demonstrate that an increase in the water coupling coefficient leads to a reduction in the peak pressure on the hole wall and the crushing zone,enabling more of the explosion energy to be utilized for crack propagation following the *** specimens exhibited distinct failure patterns,resulting in corresponding changes in fractal *** simulated pore wall pressure–time curve validated the derived theoretical results,whereas the stress cloud map and explosion energy-time curve demonstrated the buffering effect of the water *** the water coupling coefficient increases,the buffering effect of the water medium becomes increasingly prominent.

关键词： Water coupling coefficient Radial uncoupled charge Numerical simulation Fractal dimension

Opportunities and challenges in studies of mammalian hybrid speciation

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Science China(Life Sciences) 2024年第3期67卷 614-617页

作者： Hong Wu Yuxing Zhang Li Yu State Key Laboratory for Conservation and Utilization of Bio-resource in Yunnan School of Life SciencesYunnan UniversityKunming 650091China

Revealing the mechanisms of speciation remains one of the most attractive and challenging issues in the field of evolutionary biology, and is also key to understanding the biodiversity present in nature.

关键词： biodiversity attractive evolutionary

Hard carbon for sodium storage:Mechanism and performance optimization

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Nano Research 2024年第7期17卷 6038-6057页

作者： Yongxin Wang Meng Li Yu Zhang Naiqing Zhang State Key Laboratory of Urban Water resource and Environment School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China school of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Due to the shortage of lithium resource reserves and the pressure of rising prices,sodium-ion batteries have regained the attention of the public,and shown great potential for application in the fields of grid energy storage and low-speed vehicles to achieve the purpose of complementing lithium-ion batteries,so it is imperative to promote the commercial application of sodiumion *** sodium-ion battery anode materials,hard carbon is the material most likely to be used ***,there is still much work to be done before its *** review provides a comprehensive overview of the current research status from the following three ***,the microstructure and sodium storage active sites of hard carbon are ***,the mechanism of sodium storage in hard carbon is investigated,which can be broadly categorized into four model,“insertion–filling”,“adsorption–insertion”,“adsorption–filling”,and“multistage”.Finally,from the perspective of improving the electrochemical performance of hard carbon,the performance improvement strategies proposed in recent years are *** with the performance of hard carbon commercial products of some enterprises,the future development goal of hard carbon is prospected,hoping that all sectors of society can work hard for this common goal.

关键词： sodium-ion battery hard carbon mechanism performance optimization

A stable one-point quadrature rule for three-dimensional numerical manifold method

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Science China(Technological Sciences) 2024年第5期67卷 1401-1416页

作者： ZHANG Ning ZHENG Hong YANG Liang WU WenAn YUAN Chi school of Civil Engineering Qinghai UniversityQinghai810016China Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing100124China Faculty of Engineering China University of GeoscienceWuhan430074China

We present a numerically stable one-point quadrature rule for the stiffness matrix and mass matrix of the three-dimensional numerical manifold method(3D NMM).The rule simplifies the integration over irregularly shaped manifold elements and overcomes locking issues,and it does not cause spurious modes in modal *** essential idea is to transfer the integral over a manifold element to a few moments to the element center,thereby deriving a one-point integration rule by the moments and making modifications to avoid locking *** the stiffness matrix,after the virtual work is decomposed into moments,higher-order moments are modified to overcome locking issues in nearly incompressible and bending-dominated *** the mass matrix,the consistent and lumped types are derived by *** particular,the lumped type has the clear advantage of *** proposed method is naturally suitable for 3D NMM meshes automatically generated from a regular *** tests justify the accuracy improvements and the stability of the proposed procedure.

关键词： three-dimensional numerical manifold method quadrature rule locking mass lumping

Unprecedented sesquiterpene-polycyclic polyprenylated acylphloroglucinol adduct against acute myeloid leukemia via inhibiting mitochondrial complex Ⅴ

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Chinese Chemical Letters 2024年第10期35卷 331-334页

作者： Zhengyi Shi Jie Yin Yang Xiao Zhangrong Hou Fei Song Jianping Wang Qingyi Tong Changxing Qi Yonghui Zhang Hubei Key Laboratory of Natural Medicinal Chemistry and resource Evaluation School of Pharmacy Tongji Medical College Huazhong University of Science and Technology

Monosescinol A(1), the first example of sesquiterpene–polycyclic polyprenylated acylphloroglucinol(PPAP) adduct, which represented a new subclass of PPAP-type natural products, along with two new congeners with normal spiro 6/6/5 tricyclic architecture, were isolated from Hypericum longistylum. Monosescinol A possessed an unprecedented 6/5/5/6/6 pentacyclic carbon skeleton that might be assembled from the 6/6/5 carbon skeleton, via the splitting decomposition of C-3/C-14, and the attack from the C-3 in the PPAP core to C-28 in sesquiterpene section. In addition, we have firstly confirmed that 24R configuration was existed in sec–Bu containing PPAPs by single crystal diffraction data analysis of monosescinol B(2), that might provide an enlightenment in the configurational determination of sec–Bu containing PPAPs. Significantly, further pharmacological research has found that compound 1 exhibited remarkable pharmacological effects against acute myeloid leukemia(AML) cell lines, with direct inhibition of mitochondrial complex V and an increase in mitochondrial membrane potential, and led to an induction of oxidative stress, endogenous inflammation, and apoptosis of AML cells.

关键词： Cytotoxic activity Keto-enol tautomerism Plausible biosynthetic pathway PPAP adduct Single-crystal X-ray diffraction

Geochemical and Isotopic Techniques Constraints on the Origin,Evolution,and Residence Time of Low-enthalpy Geothermal Water in Western Wugongshan,SE China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 801-818页

作者： WANG Luyao LIU Kai MA Yan ZHANG Yaoyao TONG Jue JIA Wuhui ZHANG Shouchuan SUN Junliang Chinese Academy of Geological Sciences Beijing 100037China school of Water resources and Environment China University of Geoscience(Beijing)Beijing 100083China The Fourth Geological Brigade of Jiangxi Geological Bureau PingxiangJiangxi 337000China

Geothermal resources are increasingly gaining attention as a competitive,clean energy source to address the energy crisis and mitigate climate *** Wugongshan area,situated in the southeast coast geothermal belt of China,is a typical geothermal anomaly and contains abundant medium-and low-temperature geothermal *** study employed hydrogeochemical and isotopic techniques to explore the cyclic evolution of geothermal water in the western Wugongshan region,encompassing the recharge origin,water-rock interaction mechanisms,and residence *** results show that the geothermal water in the western region of Wugongshan is weakly alkaline,with low enthalpy and mineralization *** hydrochemistry of geothermal waters is dominated by Na-HCO_(3)and Na-SO_(4),while the hydrochemistry types of cold springs are all Na-HCO_(3).The hydrochemistry types of surface waters and rain waters are NaHCO_(3)or Ca-HCO_(3).The δD and δ^(18)O values reveal that the geothermal waters are recharged by atmospheric precipitation at an altitude between 550.0 and 1218.6 *** ratios of maj or solutes and isotopic compositions of^(87)Sr/^(86)Sr underscore the significant role of silicate weathering,dissolution,and cation exchange in controlling geothermal water ***,geothermal waters experienced varying degrees of mixing with cold water during their ***δ^(13)C values suggest that the primary sources of carbon in the geothermal waters were biogenic and ***δ^(34)S value suggests that the sulfates in geothermal water originate from sulfide minerals in the surrounding *** dating using 3H and^(14)C isotopes suggests that geothermal waters have a residence time exceeding 1 kaBP and undergo a long-distance cycling process.

关键词： geothermal water hydrochemistry isotope residence time Wugongshan area

Occurrence and risk assessment of azole fungicides during the urban water cycle:A year-long study along the Yangtze River,China

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Journal of Environmental Sciences 2024年第7期141卷 16-25页

作者： Yangyang Zhang Xinjie Gu Xiuwen Li Qiuyun Zhao Xiaodong Hu Rui Huang Jixiong Xu Zilong Yin Qing Zhou Aimin Li Peng Shi State Key Laboratory of Pollution Control and resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Jiangsu Province Hydraulic Research Institute Nanjing 210023China

Azole fungicides(AFs)play an important role in the prevention and treatment of fungal diseases in agricultural ***,limited studies are addressing the fate and ecological risk of AFs in the urban water cycle at a large watershed *** address this gap,we investigated the spatiotemporal distribution and ecological risk of twenty AFs in the lower reaches of the Yangtze River across four ***(CBA),tebuconazole(TBA),tricyclazole(TCA),and propiconazole(PPA)were found to be the dominant *** highest concentrations were measured in January(188.3 ng/L),and November(2197.1 ng/L),July(162.0 ng/L),and November(1801.9 ng/L),*** comparison between wastewater treatment plants(WWTPs)effluents and surface water suggested that industrial WWTPs are major sources of AFs in the Yangtze *** particular,TBA and PPA were found to be the most recalcitrant AFs in industrial WWTPs,while difenoconazole(DFA)was found to be the most potent pollutant in municipal WWTPs,with an average removal rate of less than60%.The average risk quotient(RQ)for the entire AFs was 6.45 in the fall,which was higher than in January(0.98),April(0.61),and July(0.40).This indicates that AFs in surface water posed higher environmental risks during the dry ***,the exposure risk of AFs via drinking water for sensitive populations deserves more *** study provides benchmark data on the occurrence of AFs in the lower reaches of the Yangtze River,and offers suggestions for better reduction of AFs.

关键词： Azole fungicides Spatiotemporal distribution Ecological risk Urban water cycle the Yangtze River

Impact of sedimentary environmental evolution on organic matter enrichment in Upper Paleozoic marine–continental transitional shales in the Shenfu Block， eastern Ordos Basin， China: evidence from geochemistry

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Journal of Earth Science 2024年

作者： Zhang Yanchao Yin Xiangdong Jiang Shu Ma Litao Li Jiaming school of geoscience and Technology， Southwest Petroleum University school of Sustainable Energy， China University of geosciences Wuhan EnerTech-Drilling & Production Co.，CNOOC Ltd

The shale gas exploration of marine-continental transitional facies has gained great attention in China， which is viewed as another breakthrough following the marine shale gas prior to continental shale gas. The Upper Paleozoic marine-continental transitional shales have high TOC abundance with large total thickness in the eastern Ordos Basin， progressively becoming a favorable area for exploration of transitional shale gas. Nevertheless， compared with the relatively homogeneous marine shales， the marine-continental transitional shales demonstrated strong anisotropy in the aspects of thickness， lithology and organic matter (OM). Thus， in this paper， based on the trace element and rock-eval data， we investigated the sedimentary facies， provenance， paleoclimate， paleobathymetry， and redox condition， as well as their controls on the enrichment of organic matter in the Shenfu Block， eastern Ordos basin. The results of trace element experiments indicate that the paleoenvironment of the Ordos Basin underwent a transition from a marine to a continental environment， evolving from the Benxi Formation of the Carboniferous system to the Upper Shihezi Formation of the Permian system. The provenance area is characterised by the presence of high iron and high magnesium feldspar， with a medium degree of weathering. The paleoclimate experienced alternating periods of dry heat， relatively warm wet conditions， and dry heat. The paleowater depth decreased along the sedimentary profile. With regard to the REDOX environment index， the Taiyuan Formation is the stratum exhibiting the highest degree of reduction. The detection criteria for biomarkers were found to be consistent with the inorganic geochemical characteristics. The relationship between various trace elements and TOC indicates that redox conditions are the primary factors influencing the accumulation of organic matter in transitional shale. Organic matter is more abundant in warm and humid marine and terrestrial environments t

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Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo Dong Huan Lu Hai Lin school of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment