最新刊期
卷 64 ， 期 6 ， 2025
- 摘要：For more than 20 years， our team has been committed to the development and utilization on the resources of Exocarpium Citri Grandis， and established the molecular fingerprints of psbA-trnH region， ITS region and ISSR-PCR of Exocarpium Citri Grandis. The chemical material basis and drug effect material basis of Exocarpium Citri Grandis have been demonstrated. The mechanisms of actions of Exocarpium Citri Grandis were systematically expounded. A reliable and effective quality evaluation system of Exocarpium Citri Grandis was developed， and thus the process of internationalization of Exocarpium Citri Grandis was significantly accelerated. In addition， some innovative drugs based on Exocarpium Citri Grandis have been researched and developed. These contributions together have greatly extend the industrial chain of Exocarpium Citri Grandis and played an important role in promoting rural revitalization.关键词：southern medicine;Exocarpium Citri Grandis;resource development144|75|0更新时间：2025-11-25
- 摘要：Xinhui Qinggan Tea is a novel beverage produced from near-mature fruits of Xinhui （Guangdong， China） Citrus reticulata 'Chachi'， commonly known as "Qinggan"， in which the pulp is removed and filled with tea. Its distinctive blend of fruity and tea aromas has made it particularly popular among consumers. The peel of Qinggan contains alkaloids， particularly synephrine， which is known for its therapeutic properties including vasoconstriction， brochodilation， blood pressure elevation， pupil dilation and smooth muscle stimulation. However， potential health risks associated with long-term intake of synephrine from Qinggan peel， including adverse reactions， have remained a matter of concern. To this end， this study aimed to determinate the content of synephrine of Xinhui Qinggan peel and comprehensively evaluate their safety concern as well as its processed tea products. We have established a validated quantitative methodology and determined the content of synephrine in 26 batches of Xinhui Qinggan peel samples， 45 batches of Xinhui Qinggan tea rind （without tea） samples， and 20 batches of Guangchenpi （the authentic medicinal material for Citri Reticulatae Pericarpium） samples. Based on the determination of synephrine， we further performed the health risk assessments for synephrine exposure in consumers of different ages and both genders by using the Monte Carlo simulation. The results showed that the Hazard Quotient （HQ） values for the Reasonable Maximum Exposure risk （RME risk） of synephrine exposure from Xinhui Qinggan peel and Xinhui Qinggan tea rind were below 0.02 across all groups， significantly lower than the USEPA safety threshold （HQ<1）. Overall， our results indicated that daily consumption of Xinhui Qinggan peel and Guangchenpi poses no significant health risks.关键词：Xinhui near-mature Citrus reticulata 'Chachi' （Qinggan）;synephrine;determination;health risk assessment;Monte-Carlo simulation77|41|0更新时间：2025-11-25
- 摘要：To systematically analyze and compare the effects of sun-drying， shade-drying and electric blast-drying （at 50， 60， and 70 ℃） on the quality of tender twigs and leaves of Murraya paniculata， and to provide a scientific basis for optimizing their postharvest processing methods at production areas. Morphological characteristics and thin-layer chromatography profiles were observed and compared. Differences in alcohol-soluble extractives， volatile oil content， and the contents of four flavonoid active components—murrangatin， 5，7，3'，4'，5'-pentamethoxyflavone， 5-hydroxy-3'，4'，6，7-tetramethoxyflavone， and demethylnobiletin—were determined and compared. The quality of the medicinal materials was comprehensively evaluated using the entropy weight TOPSIS method. Different drying methods significantly affected the alcohol-soluble extractives content but showed no significant impact on the volatile oil content. Compared with shade-drying， electric blast-drying at 50 ℃ significantly increased the contents of the four flavonoid components in M. paniculata from various production areas， but had no significant impact on volatile oil content. Compared with traditional shade-drying， electric blast-drying at 50 ℃ with constant temperature blast-drying significantly increased the contents of four active ingredients — murrangatin，5，7，3'，4'，5'-pentamethoxyflavone， 5-hydroxy-3'，4'，6，7-tetramethoxyflavone， and demethylnobiletin—in M. paniculata from various production areas. The comprehensive quality evaluation results indicated that electric blast-drying at 50 ℃ achieved the highest ranking in multiple production regions. Considering drying time， energy consumption， active ingredient content， and appearance，electric blast-drying at 50 ℃ can be recommended as the preferred postharvest processing method for standardized and industrialized production bases of M. paniculata.关键词：Murraya paniculata;fresh-processing;UPLC;medicinal material quality26|12|0更新时间：2025-11-25
- 摘要：The study aims to investigate the chemical composition transformation patterns of differently processed Cassiae Semen decoction pieces and to establish a scientific evaluation standard for this Lingnan-region herbal medicine. Based on UPLC-Q-TOF-MS² combined with Feature-Based Molecular Networking （FBMN）， the composition differences of raw Cassiae Semen， stir-fried Cassiae Semen and carbonized Cassiae Semen were analyzed， and the HPLC fingerprints of different processing specifications of decoction pieces were constructed. FBMN identified 90 compounds， with 40， 42 and 36 compounds （35 shared compounds） were detected in the three types of decoction pieces respectively. The deepening of processing resulted in the breakage of glycosidic bonds of glycosides （e.g. cassiaside B₂， rubrofusarin gentiobioside，etc.） and the increase of aglycone content and partial degradation. The discrimination standard was established by the ratio of peak area （RPA） of six transformation-related characteristic peaks： RPA≤0.100 for raw Cassiae Semen；0.200≤RPA≤0.500 for stir-fried Cassiae Semen；RPA>0.500 for carbonized Cassiae Semen. UPLC-Q-TOF-MS2/FBMN could be used to elucidatedynamic transformations patterns of processing， and the RPA index of HPLC fingerprint could provide a scientific basis for objective differentiation of processing specifications and determination of endpoint.关键词：Cassiae Semen;processing;chemical compositions;UPLC-Q-TOF-MS;feature-based molecular networking30|35|0更新时间：2025-11-25
- 摘要：The study is to analyze the differences in chemical components between the exocarp of Citrus grandis ‘Tomentosa’ （WP） and mesocarp of C. grandis ‘Tomentosa’ （ZP）， and provide a basis for the full utilization of C. grandis ‘Tomentosa’ resources. The UPLC-Zone TOF-MS/MS technique was used to identify the chemical substances in the WP and ZP. Principal component analysis （PCA） and orthogonal partial least squares discriminant analysis （OPLS-DA） were applied to compare and analyze the above data. Potential differential markers were screened based on the criteria of variable importance in the projection （VIP） > 1 and P≤0.05， and the contents of these markers were determined by HPLC. The results showed that the types of chemical components in the WP and ZP were relatively similar， but there were significant differences in their contents. The discrete trends of the two groups of samples were obvious， with the WP clustered into one category and the ZP into another. OPLS-DA analysis indicated that Naringin， Rhoifolin， Vicenin-2， and Meranzin hydrate were the main marker substances distinguishing the two groups of samples. Quantitative analysis showed that the content of Naringin in both groups was much higher than that of other components. The content of Naringin in the ZP was significantly higher than that in the WP， while the contents of Rhoifolin， Vicenin-2， Meranzin hydrate， Isoimperatorin， and Bergapten in the ZP were significantly lower than those in the WP. ZP is rich in flavonoid active ingredients and possesses significant medicinal and health benefits.关键词：Citrus grandis ‘Tomentosa’;mesocarp;exocarp;chemometrics34|25|0更新时间：2025-11-25
Column of special traditional Chinese herbs from Lingnan region in China
- 摘要：Two new species of Crassulaceae, Sedum baiwanense Yan S. Huang & Q. Fan and S. nankunshanense Yan S. Huang & Q. Fan,from Guangdong, China, are described and illustrated here. Phylogenetic analysis based on the internal transcribed spacer (ITS) region of nrDNA suggests that the two new species belong to Acre Clade, and are relative to S.subtile Miq., S.tianmushanense Y.C.Ho & F.Chai, and S. jiulungshanense Y.C.Ho with high support values (node posterior probabilities = 1). With high morphologically differences, we can easily distinguish species in this monophyletic group.关键词：Sedum;new species;Guangdong Province;phylogeny;ITS sequence102|313|0更新时间：2025-11-25
- 摘要：This study selected solvothermal method to prepare a zinc complex ｛［Zn（NDA）（1，2-DPE）0.5（H2O）］·0.5H2O｝n （1） with a mixed organic ligand containing conjugated structure of 2，7-naphthalenedicarboxylic acid and （E） -1，2-di （pyridin-4-yl） ethylene and Zn2+. The structure and properties of complex 1 were characterized by X-ray single crystal diffraction， infrared spectroscopy， thermogravimetric analysis， etc.， and its fluorescence detection ability for streptomycin was analyzed in depth. The analysis results of X-ray single crystal diffraction reveal that it crystallizes in the P21/c space group of the monoclinic crystal system. Research has shown that complex 1， due to its excellent fluorescence properties and stability， can be used for selective detection of streptomycin. The fitting results show that Ksv = 1.784 4 × 104 L/mol. Furthermore， further exploration of its fluorescence quenching mechanism suggests that the occurrence of fluorescence quenching may be due to energy competition absorption between chloramphenicol and complex 1.关键词：zinc complex;crystal structure;fluorescence sensing;chlortetracycline detection;fluorescence quenching mechanism38|25|0更新时间：2025-11-25
- 摘要：The reaction mechanism of potassium chelated by two α-alanine molecules （α-Ala2→K+） with hydroxyl radicals （OH） under physiological conditions （aqueous phase， 310.15 K， 1.013 × 105 Pa） was investigated using the M06-2X and MN15 density functional methods together with the SMD solvation model. Three reaction pathways were identified between α-Ala2→K+ and OH： Hydrogen abstraction by OH， OH addition to unsaturated carbon atoms， and single-electron transfer （SET） from α-Ala2→K+ to OH. Free energy calculations along the potential energy surfaces revealed that the energy barriers for hydrogen abstraction ranged from 14.0 to 56.1 kJ/mol and were all significantly exothermic. The energy barriers for OH addition ranged from 88.3 to 92.6 kJ/mol， also being exothermic. By contrast， the SET pathway from α-Ala2→K+ to OH exhibited a prohibitively high barrier of 795.9 kJ/mol. These results suggest that α-Ala2→K+ can effectively scavenge hydroxyl radicals through hydrogen abstraction and addition reactions under physiological conditions.关键词：potassium chelated by two α-alanine molecules;hydroxyl radical;density functional theory;self-consistent reaction field model;transition state;single electron transfer;free energy barrier14|6|0更新时间：2025-11-25
- 摘要：In AC magnetic field，eddy current is generated in the metal.Due to the coupling of eddy currents and the AC magnetic field，the magnetic induced force is produced on the metal，which is significant in specific research fields such as gravitational wave detection.When the magnetic field frequency is single，the magnetic force generated is easy to analyze and calculate.However，when the magnetic field contains multiple frequency components，the magnetic force acting on the metal becomes complex.In this study，we investigate the composition of magnetic forces induced by eddy current under dual-frequency magnetic field through combination of theoretical analysis and simulation calculations and reveal the down-converting effect of the magnetic forces，which is critical for precision measurement tasks.Finally，we propose that employing AC magnetic susceptibility to calculate magnetic force can significantly reduce computation time while maintaining analytical accuracy，thereby establishing a rapid and reliable method for subsequent research on metal magnetic force.关键词：magnetic force;AC magnetic field;eddy current;down-converting effect;AC magnetic susceptibility34|1|0更新时间：2025-11-25
- 摘要：This paper develops a dynamical model for the in-plane motion of wind turbine blades，systematically deriving nonlinear partial differential governing equations based on Hamilton's principle.The model incorporates gravitational loads，aerodynamic loads，and geometric nonlinearities induced by large deflections，to establish a continuous system characterized by second-order nonlinearities.Through Galerkin discretization with assumed cantilever mode function under constant rotational speed，the original partial differential equations are reduced to a second-order nonlinear Mathieu-Duffing system featuring both parametric excitation and direct external excitation.To investigate the bifurcation characteristics of this nonlinear dynamical system，an innovative time-domain minimum residual method is proposed and implemented. The results reveal rich nonlinear dynamical behaviors under parametric excitation：stable periodic oscillations dominate specific parameter regimes，while transitions to chaotic responses emerge through control parameter variations.关键词：wind turbine;blades;nonlinear vibrations;time-domain minimum residual method11|2|0更新时间：2025-11-25
- 摘要：A trajectory similarity measure combining improved Word2Vec method and dynamic semantic map is proposed. The method learns the bayonet sequence correlation by the Word2Vec model with added destination constraint and establishes explicit connection with the destination； on the other hand， the dynamic semantic map can build the basis for the similarity measure of time and travel behavior dimension. The experimental results indicate that urban functional zones exhibit significant dynamic changes throughout the day. In the trajectory hierarchical clustering task， the average AC value of the method in this paper is 0.36 lower than that of the method chosen for comparison， further demonstrating its superior similarity measurement capability and robustness.关键词：trajectory similarity;destination prediction;Word2Vec;dynamic semantic map36|9|0更新时间：2025-11-25
- 摘要：This study takes undisturbed specimens of various types as the research object which from a typical soft soil road-bridge transition section in Zhuhai as the research object. Through laboratory tests， including basic physical property tests， triaxial shear tests， and SEM analysis， the macro- and micro-properties of the in-situ undisturbed specimens were obtained. The test results show that the undisturbed specimens have a high natural water content， which significantly decreases after vacuum combined surcharge preloading. The internal friction angle and cohesion of the fill are 36.957° and 1.511 kPa， respectively. The clay exhibits higher cohesion and internal friction angle than the silty soil， and both parameters increase in clay and silty soil after preloading. As the depth of the soil increases， the microscopic pore size decreases significantly. After vacuum combined surcharge preloading， the fractal dimension of the soil structure decreases markedly， the aggregation degree of cohesive soil is enhanced， and cohesion increases significantly.关键词：macroscopic mechanical properties;microscopic mechanism;basic physical properties;triaxial test;SEM23|11|0更新时间：2025-11-25
- 摘要：The Al-Y2O3-Sm2O3 ternary sintering additive was used to conduct low-temperature sintering experiments on AlN ceramics.The effects of Y₂O₃ and Sm2O3 additive amounts on the microstructure， thermodynamic properties of AlN ceramics were studied， when the amount of aluminum is fixed.The experiments indicate that adding the ternary sintering additive allows AlN ceramics to achieve densification at 1 750 ℃，which is reduced by 150 ℃ compared to AlN ceramics without sintering additives. Also the bending strength reaches （474±25） MPa，and the thermal conductivity is
- 摘要：A surrogate model based on graph neural networks（GNN） is proposed for truss structure response prediction．Based on graph theory，a graph representation method is employed to describe the topological characteristics and physical information of truss structures．Graph convolution is used to establish correlations among variables，achieving dimensionality reduction of the training space through structural geometric and physical features．Furthermore，an attention mechanism is integrated into the model to effectively incorporate node and edge features，with feature weights of neighboring nodes and edges adaptively assigned according to element stiffness，thereby accurately simulating force transmission paths during training．Three truss structures with 10，19，and 27 design variables，respectively，serve as examples for evaluating prediction accuracy using the mean absolute percentage error metric．Comparative analysis indicates that the prediction error of the GNN model decreases significantly with an increasing number of training samples and remains exceptionally.关键词：surrogate model;GNN;structural analysis;prediction accuracy;computational efficiency36|25|0更新时间：2025-11-25
- 摘要：Laboratory model tests on soft soils with high water content were conducted using particle image velocimetry（PIV） to observe the development trends of horizontal and vertical displacement fields of soil around the pile during pile driving at different depths under varying soil states. The results show that： with the increase in horizontal distance from the pile center， the horizontal displacement of soil adjacent to the pile exhibits an obvious spatial attenuation law， and both the disturbance intensity and influence depth weaken gradually；the higher the water content of soft soil， the smaller the horizontal and vertical influence zones；at the end of pile driving， the horizontal and vertical influence ranges of soft plastic soft soil are 3.9 times and 1.9 times the pile diameter， respectively， while those of fluid plastic soft soil are 1.8 times and 1.2 times the pile diameter；when the soft soil state changes from soft plastic to fluid plastic， the relationship between penetration depth and horizontal influence zone range transforms from nonlinear to linear；soft plastic soft soil has higher strength， with intense and concentrated pressure responses， whereas fluid plastic soft soil shows stronger fluidity and more dispersed pressure responses.关键词：Zhuhai soft clay;particle image velocimetry;tracer particles;displacement field36|45|0更新时间：2025-11-25
- 摘要：The migration of extensional centers is a key feature of continental lithosphere evolution. In the South China Sea （SCS）， the extensional center has migrated southward， as evidenced by the southward movement of rift basins， associated magmatic activity， and mid-ocean ridge spreading centers. Seismic tomography and plate reconstructions suggest potential causes for this migration， which may be related to lithospheric rheology and changes in regional plate driving forces. However， the underlying geodynamic mechanisms remain unclear. In this study， 2D thermo-mechanical numerical modeling was conducted using a one-sided rifting setup to examine how accelerated extension and variation in lithospheric mantle properties affect rift migration. The results reveal two key findings：1）A thin continental lithospheric mantle promotes rift migration during extension. Key mechanisms include lower stress concentration rates， wider lithospheric deformation zones， and longer rifting duration. 2）With asymmetric boundary extension， the rift axis shifts toward the direction of faster stretching. Greater acceleration leads to more pronounced migration alignment. Modeling results match geological observations： southward rift migration in the South China Sea and magmatic underplating beneath its northern margin. This suggests that lithospheric structure and asymmetric extension together control the rift evolution dynamics in the region.关键词：rift basin;numerical modeling;variable-rate rifting;rift basin migration;South China Sea basin33|10|0更新时间：2025-11-25
- 摘要：The Huaihe River Basin in eastern China is located in a climate-sensitive transition zone between northern and southern China. It is significantly influenced by the monsoon and experiences frequent floods. A detailed field investigation in the basin revealed a soil sedimentary profile on the steep scarp of the first terrace on the north bank of the Huaihe River at Zhangwan Village， Zhengyang County， Henan Province. This profile contains five layers of overbank flood deposits （OFD1-5）. Sediment samples were collected from the profile for particle size analysis， magnetic susceptibility measurement， and optically stimulated luminescence （OSL） dating. The results show that： 1） The OFDs are predominantly composed of coarse silt （>48%）， whereas the palaeo-floodplain and palaeo-riverbed sand layers are primarily composed of sand （>88%）. Particle-size end-element analysis indicated that OFD1-5 were all palaeo-overbank flood deposits formed by hydrodynamic action in an overbank flood environment and subsequently underwent pedogenic modification. 2） The magnetic susceptibility values of OFDs fall between those of the modern topsoil layer and the palaeo-floodplain sand layer. The values of OFD5， OFD4， and OFD3 are significantly higher than those of OFD2 and OFD1. This might be due to the different degrees of weathering and pedogenesis after the deposition of overbank flood deposits. 3） OSL dating and stratigraphic chronological framework analysis indicated that the sedimentary profile recorded five extraordinary palaeo-flood events in the late Holocene from 1 800 to 1 400 a in the upper Huaihe River， which corresponded to the severe climate deterioration during the Wei， Jin， and Northern and Southern Dynasties （220-589 AD） in China， reflecting a response to global climate anomalies. This study identifies a series of late Holocene palaeo-flood events between 1 800 and 1 400 a in the upper Huai River basin and elucidates their climatic context， providing critical insights for flood risk assessment and the development of mitigation strategies in the region.关键词：palaeo-flood events;OSL dating;climate background;Huaihe River Basin29|16|0更新时间：2025-11-25
- 摘要：The Takermohuer Desert is the largest desert in the Ili River Basin and exemplifies a typical fixed and semi-fixed desert in China， formed under prevailing westerly climate influences. Using the Google Earth Engine （GEE） platform and Landsat imagery， this study developed an Albedo-NDVI feature space model for the Takermohuer Desert from 1992 to 2023 and applied the Geodetector model to analyze the driving factors behind desertification evolution quantitatively. The results show that： 1） From 1992 to 1997， the region experienced a development phase， marked by expanding extremely severe desertified land and shrinking severely desertified areas. Conversely， from 1997 to 2023， it entered a reversal phase， with decreases in extremely severe and severe desertified land， and increases in mildly and non-desertified areas. 2） The spatial distribution of desertification varies significantly： areas with extremely severe and severe desertification gradually declined， while mild and non-desertified zones expanded significantly. Desertification progressed more rapidly in the central and western regions， while the eastern part displayed alternating phases of extremely severe and severe desertification. 3） The evolution of desertification was influenced by both natural and anthropogenic factors. Topography determined the spatial distribution pattern of desertified land， and policy factors play an important role. Land use and land cover change （LUCC）， slope， and precipitation emerged as the main driving factors， with explanatory powers of 0.502， 0.118 and 0.082， respectively. The interaction between these factors was significantly stronger than individual effects， demonstrating either nonlinear or two-factor enhancements， without any weakening or independent influences.关键词：Takermohuer Desert;Desertification;Albedo-NDVI feature space;geodetector29|14|0更新时间：2025-11-25
- 摘要：Against the backdrop of COVID-19， we consider the scenario where three groups of people are simultaneously infectious in the age-structured infectious disease problem， it was established that a virus mutation epidemic model with vertical transmission and latency period. Firstly， the existence and uniqueness of non-negative solutions are proved， and the basic regeneration number of the model was obtained by using the qualitative theory of ordinary differential equation. Secondly， the sufficient conditions for the existence and stability of the disease-free equilibrium point are proved by using the stability theory of ordinary differential equationv. Finally， the existence of the endemic equilibrium point is demonstrated.关键词：vertical transmission;virus mutation;epidemic model41|13|0更新时间：2025-11-25
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