最新刊期
      卷 62 ， 期 2 ， 2023

        Invited review

      • CHANG Huailiang,LI Weiping
        Vol. 62, Issue 2, Pages: 1-9(2023) DOI: 10.13471/j.cnki.acta.snus.2022A093
        摘要：This is a survey of using NMSP method to study higher genus Gromov-Witten invariants of Calabi-Yau quintics. It emphasizes on how and why the various methods are introduced to solve several important conjectures for higher genus Gromov-Witten invariants of Calabi-Yau quintics.  
          
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        发布时间：2023-11-01

        Mangrove fisheries carbon sink column

      • YANG Huirong,ZENG Zeqian,LIU Jianxin
        Vol. 62, Issue 2, Pages: 10-16(2023) DOI: 10.13471/j.cnki.acta.snus.2022E072
        摘要：Fishery carbon sink refers to the process and mechanism of using aquatic organisms in fishery production activities to absorb CO2 dissolved in the atmosphere in the water body， and transfer the carbon converted into aquatic products out of the water body through harvesting or biodeposition to settle it on the bottom. Since the carbon absorbed by these aquatic organisms is reused or stored in this process， the ability of aquatic ecosystems to absorb and store atmospheric CO2 is enhanced， which is of great significance for achieving “carbon neutrality”.This review systematically summaries the research progress of mangrove fishery carbon sink in recent years， describes the carbon cycle process of mangrove water ecosystem by analyzing the carbon sink function of mangrove aquatic organisms. Finally， the paper discusses the current situation and prospect of the industrial model formed on the basis of mangrove fishery carbon sink for further studying the material cycle and energy flow of mangrove ecosystem， improving the technology of fishery carbon sink and providing the theoretical basis to achieve carbon neutrality.  
        关键词：fishery carbon sink;carbon sink function;carbon sequestration capacity;carbon budget   
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        发布时间：2023-11-01
      • PENG Yisheng,YANG Yuting,LIANG Jin,HU Bowen,LIU Jianxin,HE Ziying
        Vol. 62, Issue 2, Pages: 17-27(2023) DOI: 10.13471/j.cnki.acta.snus.2023E002
        摘要：Macrobenthic bioturbation is a key process to facilitate material transportation and energy flow in mangrove ecosystem. Macrobenthos can modify the physicochemical properties of sediments， and drive the composition and function of microbial community， which is of great significance to the biogeochemical cycle in mangrove. This article focused on the current status of the studies on macrobenthic bioturbation and its effects on microorganism communities， and the biogeochemical cycle mediated by microorganisms in mangrove. We respectively reviewed the spatial and temporal distribution patterns and their drivers of macrobenthos and microorganisms， and discussed the physical and chemical linkage between macrobenthic bioturbation and microbial ecological functionalities. The perspectives of community composition， interactive mechanism and ecological functionalities among macrobenthos， microbiome and mangrove has also been considered.  
        关键词：mangrove;macrobenthos;microbial community;bioturbation;biogeochemical cycle   
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        发布时间：2023-11-01
      • YANG Huirong,FANG Chang,GAO Junchao,JIAO Fang
        Vol. 62, Issue 2, Pages: 28-36(2023) DOI: 10.13471/j.cnki.acta.snus.2022E071
        摘要：The microbial communities in mangrove sediments have evolved spatial distribution features with different characteristic and carbon sink capacity under the environment-specific selection pressure. The composition， diversity and potential carbon sink capacity of the sediment microbial communities were analyzed using 16S rRNA high-throughput sequencing in a typical mangrove area in Shantou city， eastern Guangdong province. The results showed that the dominant phyla in mangrove sediment were Proteobacteria， Chloroflexi and Desulfobacterota， and the dominant microorganisms at the genus level were derived from unclassified_Gammaproteobacteria， Anaerolinea and Woeseia. Sediments with low pollution and immature forest had higher richness and lower evenness， while sediments with moderate levels of pollution and mature forest stands had relatively high biodiversity and evenness. With increasing depth， the microbial α-diversity indexes such as richness， diversity and evenness of sediment microorganisms showed a decreasing trend， among which the diversity index decreased most significantly （P < 0.05）. The mangrove areas with less pollution and immature forest stands had the optimal microbial carbon sink capacity while there was no significant relationship between microbial carbon sink capacity and sampling depth. This study provide a theoretical basis for the resource utilization of mangrove sediment microorganisms.  
        关键词：mangrove sediment;microbial community;spatial distribution;carbon sink   
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        发布时间：2023-11-01
      • PENG Yisheng,ZHUANG Xueyin,ZHAO Lili,WANG Zihao,GAO Junchao,WANG Bingxin,HE Ziying
        Vol. 62, Issue 2, Pages: 37-46(2023) DOI: 10.13471/j.cnki.acta.snus.2023E001
        摘要：Developing the efficient carbon sequestration capability of the mangrove ecosystem is one of the fundamental methods for realizing carbon neutralization in China. However， the efficiency of mangrove carbon sequestration is determined by various factors. This study investigated the effects of species choice and tidal flat elevation on carbon sequestration in the early stage of the mangrove ecological restoration program. It provided a certain reference for the site selection and species choice of mangrove ecological restoration based on carbon sink function. In this study， three mangrove plantations including high-intertidal Aegiceras corniculatum （HAc）， low-intertidal Sonneratia apetala （LSa） and high-intertidal S. apetala （HSa） were selected from the ecological restoration program in Niutianyang， Shantou City， Guangdong Province. The plant growth， biomass， carbon storage as well as surface soils （0-60 cm） physical-chemical features were measured and estimated in the second and third years after afforestation to analyze the effects of species choice and tidal flat elevation on mangrove carbon storage. The results showed that the colonization of mangroves led to acidification and salinization as well as nutrient accumulation in soil， while the proportion of exogenous organic carbon supply increased with the extension of afforestation time. After 3 years of afforestation， the native species plantation HAc obtained higher carbon storage per unit area ［plant carbon density （36.16±2.35） t·hm-2； system carbon density （70.14±3.15） t·hm-2］ by virtue of higher plant density， compared to the exotic species plantation HSa ［plant carbon density （16.00±3.76） t·hm-2； system carbon density （48.54±2.38） t·hm-2］. While inundation stress promoted the accumulation of biomass and carbon stock in S. apetala seedlings， prolonged tidal flushing reduced the quantity and stability of soil organic carbon. Therefore， the carbon density of LSa plantation ［plant carbon density （34.59±8.85） t·hm-2； system carbon density （61.03±2.57） t·hm-2］ was significantly higher than the HSa plantation， but the soil TOC and POC content were lower in deep tidal flat elevation zone.  
        关键词：ecological restoration;carbon sequestration;mangrove;species choice;tidal flat elevation   
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        发布时间：2023-11-01

        Research articles

      • YANG Mei,FENG Bo,WANG Fanghai
        Vol. 62, Issue 2, Pages: 47-50(2023) DOI: 10.13471/j.cnki.acta.snus.2022E019
        摘要：Tramtrack（ttk） gene transcription products are important transcription factors， which can regulate the development， differentiation and sexual behavior of organisms. In this study， a 1 657 bp cDNA sequence of ttk was identified from the transcriptome database of Sogatella furcifera. The open reading frame is 1 377 bp in length and encodes a protein composed of 458 amino acids. It has a typical BTB domain and a zinc finger structure. The phylogenetic tree shows that ttk of S. furcifera is closely homologous to that of Zygaena filipendulae， Cimex lectularius and Nilaparvata lugens. Quantitative detection results showed that the transcriptional level of ttk was higher in the 1st instar nymphs， but decreased to a lower level in the 2nd instar nymphs. From the 3rd instar， ttk expression increased gradually with instar growth， and at the 5th instar nymphs， ttk expression was more than twice as high as that in the 3rd instar nymphs. This is the first in detail investigation on ttk gene structure of white backed planthopper， and the results provide a foundation for further and function and regulation study of ttk gene， in the growth and development of rice planthopper in the future.  
        关键词：tramtrack（ttk）;Sogatella furcifera;nymph;gene expression   
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        发布时间：2023-11-01
      • XU Yaqi,JIN Zhiping,ZHANG Qian,LI Wei,ZHANG Guirong
        Vol. 62, Issue 2, Pages: 51-59(2023) DOI: 10.13471/j.cnki.acta.snus.2022E014
        摘要：Sleep is a key physiological process to maintain the homeostasis of the human circadian rhythm， and sleep deprivation （SD） caused by subjective and objective reasons is very common. The research on the relationship between SD and fertility is attracting more and more attention.In this study， the modified multiple platform method （MMPM） was used to establish the sleep deprivation model of female Wistar rats. The general conditions， ovarian pathology， oestrus cycle， mating rate and pregnancy rate of the rats were investigated to determine the effect of SD on the fertility of female rats；The new generation sequencing （NGS） technology was used to study the differences of ovarian transcriptome and epigenetic in SD female rats by RNA sequencing （RNA-Seq） and DNA methylation sequencing.The results showed that SD led to abnormal estrous cycle， decreased pregnancy rate and pathological changes of ovary in female rats；101 significantly differentially expressed genes （52 up-regulated genes and 49 down-regulated genes） were found in the ovarian tissue of SD rats，and 26 methylation significantly different regions were found between the SD50 group and the control group， but no changes in methylation levels were detected at all sites of the above 101 differentially expressed genes.The difference of fertility index of SD female rats showed that SD led to the decrease of fertility of female Wistar rats； The differentially expressed genes and methylation differences in the ovaries of SD rats indicate that SD may affect the gonadal function of female animals through gene transcription and epigenetic regulation.  
        关键词：sleep deprivation;fertility;ovary;RNA sequencing;DNA methylation sequencing   
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        发布时间：2023-11-01
      • LI Ziyang,HUANG Nuoer,HUANG Qisen,ZENG Meiying,YANG Yuan,SHE Zhigang,LI Chunyuan,DING Weijia
        Vol. 62, Issue 2, Pages: 60-65(2023) DOI: 10.13471/j.cnki.acta.snus.2022C016
        摘要：The study investigated the metabolites of an endophytic fungus Phoma herbarum L28 derived from the mangrove plant Myoporum bontioides A. Gray. The fungus was fermented in the rice medium. Ten monomeric compounds were isolated and identified as fusarihexin A （1），fusarihexin B （2），botryosphaerihydrofuran （3），N1-methyl-2-pyridone-5-carboxamide （4），4′，5，6-trihydroxy-7-methoxyisoflavone （5），ascomfuran A （6），4-hydroxyphenylacetic acid （7）， protocatechuic acid （8），thymidine （9） and nortetillapyrone （10） by the modern chromatography technology and spectral analysis. Among them， compounds 1， 2， 3， 4， 5 and 10 were firstly isolated from Phoma sp. The activity bioassay via the double dilution method showed that the antimicrobial activities of following compounds were strong， they are compounds 1 and 2 against Escherichia coli with O78 serotype， compounds 3 and 10 against Fusarium graminearum， and compound 4 against Fusarium oxysporum respectively.  
        关键词：Myoporum bontioides A. Gray;Phoma herbarum;metabolites;antimicrobial activity   
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        发布时间：2023-11-01
      • CHEN Fubin,LI Zhaoxian,XIE Zhuang
        Vol. 62, Issue 2, Pages: 66-72(2023) DOI: 10.13471/j.cnki.acta.snus.2022C014
        摘要：Flexible composite microelectrodes were prepared using poly（3，4-ethylenedioxythiophene）： poly（styrene sulfonate） （PEDOT：PSS） conductive polymer and multi-walled carbon nanotubes （MWCNTs） in combination with bis-trifluoromethanesulfonic acid lithium amide （LiTFSI） doping. A facile spray printing technique was developed to pattern the PEDOT：PSS/MWCNTs composite electrodes with high conductivity and excellent flexibility， which can be generated on various substrates. The study found that， based on the optimization of the spray conditions， the high current response and stable thin-film electrochemical sensing electrodes can be realized. And flexible electrochemical sensor was established to detect hydrogen peroxide and dopamine in the buffer solution at concentrations ranging from 1 μmol/L to 500 μmol/L. Such flexible electrodes are expected to be further applied in the fields of wearable electronics and monitoring of biochemical signals.  
        关键词：conducting polymer;carbon nanotubes;composite electrodes;electrochemical sensing;flexible electronics   
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        发布时间：2023-11-01
      • LI Bin,LIU Fang,ZHANG Xuejiao,WANG Han,FAN Yanjie,JIANG Chunxu,WANG Zuocheng
        Vol. 62, Issue 2, Pages: 73-82(2023) DOI: 10.13471/j.cnki.acta.snus.2022C006
        摘要：Using M06-2X and MN15 methods of density functional theory， combining with SMD model method of self consistent reaction field theory， the chiral flip of amphoteric lysine molecule catalyzed by hydroxyl anion in water-liquid phase environment was investigated. The study of reaction process shows that through the process of extracting α-H proton from hydroxyl anion water clusters and extracting H proton of water clusters from carbanion α-C， lysine molecules could achieve chiral flip. The potential energy surface shows that the energy barrier of the lysine molecules chiral flip rate-determining step is between 51.1 kJ/mol and 59.9 kJ/mol when the clusters of hydroxyl anion water molecules interact with α-H and carbonyl O hydrogen bonds； the energy barrier of the lysine molecules chiral flip rate-determining step is between 52.8 and 58.0 kJ/mol when the clusters of hydroxyl anion water molecules interact with α-H and amino group N hydrogen bonds， they are much lower than the energy barrier 110 kJ/mol of chiral flip of amphoteric lysine molecule in water-liquid phase environment. The results show that the hydroxyl anions play a catalytic role on the chiral flip of lysine molecules in water-liquid phase environment， alkaline environment is insalubrious.  
        关键词：lysine;chiral flip;density functional theory;self consistent reaction field theory;transition state;energy barrier   
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        发布时间：2023-11-01
      • GAO Yan,WU Xiaodong,TIAN Jiayi
        Vol. 62, Issue 2, Pages: 83-92(2023) DOI: 10.13471/j.cnki.acta.snus.2022D019
        摘要：In order to understand the characteristics of ground subsidence with underground karst caves caused by engineering activities， the numerical simulation based on the finite element method is adopted to analyze the ground subsidence response containing different forms of underground caverns subjected to vertical load. The influence of dimension， depth， shape of underground cavern and magnitude of the vertical load are explored separately. The results show that the larger the size of underground cavern， the shallower the buried depth， the larger the shape coefficient， and the larger the load， the larger the ground subsidence generated. The shapes of the ground subsidence curves are all bell-shaped and conform to the Gaussian distribution law. The grey correlation analysis shows that the size and shape of underground cavern are sensitive to the maximum ground subsidence value. That is， the geometry of underground cavern has an important effect on the ground subsidence. The land subsidence curves obtained by the numerical simulation are trained through the deep neural network. The error between the predicted value and the calculated value after training is within 5%. The deep neural network can be used as an effective method to predict the ground subsidence caused by the construction of the foundation with underground karst caves.  
        关键词：ground subsidence;karst cave;grey correlation analysis;machine learning;deep neural network   
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        发布时间：2023-11-01
      • HUANG Yangman,CHEN Xiaohong
        Vol. 62, Issue 2, Pages: 93-103(2023) DOI: 10.13471/j.cnki.acta.snus.2022D004
        摘要：Taking the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) as the research area, this study 1) considered the interaction between water ecology and human society, internal and external environmental changes, 2) constructed an index system that can reflect the water ecological state of the GBA more comprehensively, and 3) quantified the water ecological state of the GBA and its evolution trend from 2010 to 2019. Concerning the water ecology risks faced by the GBA, seven driving factors were selected, such as the annual runoff of the Xijiang River and the Beijiang River, the downstream tidal level, and the urbanization rate of the GBA. Taking the driving factors as the input and the four water ecological state indices as the output, the water ecological state reactor of the river network urban agglomeration in the GBA was constructed and its driving mechanism was studied. Results showed that 1) the water ecological state of the GBA has been improving in the past ten years; 2) the aquatic state was greatly affected by the annual runoff of the Xijiang River and downstream salinity; 3) the habitat index was under the rapid urbanization which shows a downward trend, but the rate of decline has slowed year by year; 4) meanwhile, rapid urbanization has shown an improvement of urban sewage treatment and effective control of the salt tidal upward, which has a positive impact on the improvement of the water quality in the GBA; 5) the water security of the GBA continues to improve despite the influence of changes in the diversion ratio and natural disasters.  
        关键词：GBA;water ecology status;driving factors;water ecology status reactor;ecology response   
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        发布时间：2023-11-01
      • FENG Yingying,HU Maochuan,TAN Xuezhi,LIU Bingjun
        Vol. 62, Issue 2, Pages: 104-112(2023) DOI: 10.13471/j.cnki.acta.snus.2022D031
        摘要：The reconstruction of historical land use has essential significance for long-term land cover change research. In an effort to better clarify the historical land use evolution， this study developed a highly automated historical map reconstruction technique based on a 1∶50 000 military topographic map of 1930. Specifically， we integrated alignment， calibration， reconstruction， and correction for reconstructing the land use pattern of the Mei River Basin. The study adopted the land use transition matrix， landscape pattern index， and moving window method for analyzing spatial-temporal changes in watershed landscape patterns based on the land use data in 1930，1980， and 2020. The results showed that military topographic maps could be applied to related research on land use change after the acceptable registration， error control， and digitization of the historical map reconstruction model. With the urbanization and the construction of large-scale water conservancy projects， the proportion of land use types constantly changed， while the transfer and exchange of cultivated land， forest and grassland， and urban-rural land were quite prominent between 1930 and 2020. At the class level， forest and grassland were the dominant landscape but the urban-rural land developed intensively under the influence of human activities. In terms of the landscape level， land use distribution had gradually developed equally and the fragmentation and heterogeneity had increased significantly in the downstream areas. This study provided a reference for the reconstruction of historical and geographical elements， and had great significance for the land use change and landscape pattern of the Mei River Basin in Guangdong Province.  
        关键词：historical land use;reconstruction;historical maps;GIS technique;landscape pattern   
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        发布时间：2023-11-01
      • HUANG Yanan
        Vol. 62, Issue 2, Pages: 113-122(2023) DOI: 10.13471/j.cnki.acta.snus.2022D024
        摘要：The 239+240Pu is a highly toxic radionuclide in the environment， and it is also the focus of nuclear safety assessment and radioactive pollution prevention. This study mainly uses published data from 329 stations to analyze the 239+240Pu amount in the air， soils， river sediments， and lake sediments in coastal provinces in China， thus， providing a three-dimensional description of the sources and levels of the 239+240Pu in the environment of the area. On this basis， the study established a relative evaluation system of the 239+240Pu level in the environment of 1 μBq/m3 or 1 mBq/g. The results show that the 239+240Pu in the air， soils， rivers and lakes of coastal provinces are at a low quasi-background level， indicating that they are from global fallout， have nothing to do with the operation of Chinese nuclear power plants （NPPs）， and have no safety risk at present in the environment.  
        关键词：239+240Pu;environment;240Pu/239Pu;coastal provinces;level   
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        发布时间：2023-11-01
      • LUO Qing,CHEN Zijian,LIN Wenshi,JIANG Baolin,CAO Qimin,LI Fangzhou
        Vol. 62, Issue 2, Pages: 123-136(2023) DOI: 10.13471/j.cnki.acta.snus.2022D010
        摘要：This study used the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) version 4.1.2 to simulate a warm-sector heavy rainfall (WSHR) event that occurred over coastal Southern China in 2014. To investigate the effects of the concentration of sea salt aerosols (SSA) on the development of WSHR, different levels of SSA emission were incorporated in three separate experiments (CTL, LOW, and HIGH). The distribution of precipitation and hydrometeors, the microphysical processes, and the release of latent heat resulting from the rainfall in all three simulations were analyzed. Results show that SSA mass concentration can affect the rainfall area: the LOW experiment shows dispersed rainfall, whereas the HIGH experiment presents concentrated rainfall. Under the situation of low (high) SSA emission: the concentration of cloud condensation nuclei during rainfall decreases (increases), the mixing ratio of rain and graupel increases (decreases), and microphysical processes, particularly the automatic conversion of cloud water into rainwater and accretion of cloud water by rain, are enhanced (weakened), more (less) latent heat is released, and the updrafts are enhanced (weakened); these result in an increase (decrease) of accumulated precipitation and rain rate.  
        关键词：sea salt aerosols;warm-sector heavy rainfall;microphysical effects;WRF-Chem model   
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      • LI Dong,WU Hongsheng,LI Xue,LIN Binbin,CHANG Dan,LIU Jiankun
        Vol. 62, Issue 2, Pages: 137-145(2023) DOI: 10.13471/j.cnki.acta.snus.2022D005
        摘要：The HS-Small（HSS） model can reflect the decrease of the shear modulus of soft soil with strain in the small range and describe hardening and dilatancy behavior. In the present study，the conventional oedometer test， triaxial experiment， and resonant column test were conducted to obtain the parameters of the HSS model for typical soft soil in Zhuhai and the relationship between these parameters. Test results show that the effective shear strength index c' of backfill is close to zero， which is less than that of silt and silty soil， but φ' larger than silt and silty soil. Besides the loading-unloading tangent modulus Eurref of silt and silty soil is about 2.66 ~ 3.39 times than the triaxial tangent modulus E50ref. However， the consolidation tangent modulus Eoedref of backfill soil is significantly greater than triaxial tangent modulus， which is about 2.89 times of E50ref. In addition， the loading-unloading tangent modulus Eurref of silt and silty soil under reference confining pressure of 100 kPa is 8.02 and 10.89 MPa， respectively， showing proportional relationship with the consolidation tangent modulus is in the range of 3.6~4.1 .  
        关键词：soft soil in Zhuhai;HSS model;parameter calibration;shear strength;damping ratio   
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        发布时间：2023-11-01
      • DING Yuelong,GAO Teng,ZHAO Chunzi,ZHU Weihong
        Vol. 62, Issue 2, Pages: 146-155(2023) DOI: 10.13471/j.cnki.acta.snus.2022D011
        摘要：To objectively understand the current situation of water resources carrying capacity in the construction and development of Harbin-Changchun urban agglomeration and ensure the sustainable development of water resources development and utilization, this study constructs the evaluation system of water resources carrying capacity of Harbin-Changchun urban agglomeration and adopts the improved entropy weight TOPSIS model, spatial autocorrelation analysis and coupling coordination degree evaluation model to comprehensively evaluate the spatial and temporal patterns of water resources carrying capacity of Harbin-Changchun urban agglomeration and the coupling coordination degree among subsystems from 2012 to 2019. The results show that: 1) The water resources carrying capacity of Harbin-Changchun urban agglomeration shows a trend of decreasing first and then increasing, and the overall is in reasonable state of water resources, and water resources endowment is the main factor affecting the improvement of water resources carrying capacity. 2) The spatial distribution of water resources carrying capacity of cities in Heilongjiang Province is better than cities in Jilin Province. 3) Among the subsystems in the urban agglomeration, the socio-economic subsystem score (0.22) is the highest, followed by the water resources subsystem (0.18) and the ecological environment subsystem (0.07) is the lowest. The score of the water resources subsystem varies greatly among cities and is mainly influenced by per capita water resources, water production modulus, and annual precipitation. 4) There is a strong positive correlation between the water resources carrying capacity of urban agglomerations and the coupling coordination degree, and the average coupling coordination degree of the Harbin-Changchun urban agglomeration is 0.37, with a low overall level and in a state of slight imbalance.  
        关键词：water resources;Harbin-Changchun urban agglomeration;water resources carrying capacity;improved entropy method;TOPSIS model;coupling coordination degree   
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        发布时间：2023-11-01
      • ZHOU Lang,XU Chunguang
        Vol. 62, Issue 2, Pages: 156-164(2023) DOI: 10.13471/j.cnki.acta.snus.2022B038
        摘要：We carried out numerical simulations of the flow field of the sharp leading edges of an X-51A-like aircraft using the three-dimensional Navier-Stokes(N-S) equations and the SST k-ω turbulence model after verifying the accuracy of the numerical simulation method by comparing it with the experimental data from the published literature. On this basis, we analyzed the heat reduction mechanism and effect of the sharp leading edges with the porous counterflowing jet under different jet exit sizes, jet pitches, and jet expansion angles. The results show that the configuration of the porous counterflowing jet significantly affects the flow field at the leading edge of the vehicle and proper configurations can effectively reduce the heat. Increasing the jet pitch reduces the heat flux of the sharp leading edges; enlarging the jet exit size and jet expansion angle brings similar effects. Moreover, for the same parameter RL, which is the ratio of jet pitch and exit size, the smaller the exit size of the counterflowing jet, the more heat reduction.  
        关键词：hypersonic;heat reduction;porous;counterflowing jet;sharp leading edges   
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        发布时间：2023-11-01
      • MENG Xin
        Vol. 62, Issue 2, Pages: 165-171(2023) DOI: 10.13471/j.cnki.acta.snus.2021A022
        摘要：The boundary value problem for a class of coupled system of nonlinear Caputo fractional q-difference equations is considered. The existence of solutions for the coupled system is obtained by using the Leray-Schauder nonlinear alternative and the Altman fixed point theorem. As applications， some examples are presented to illustrate the main results.  
        关键词：fractional q-difference equation;coupled system;value problems;Leray-Schauder nonlinear alternative   
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        发布时间：2023-11-01
      • HU Tianyi,DOU Yanni
        Vol. 62, Issue 2, Pages: 172-180(2023) DOI: 10.13471/j.cnki.acta.snus.2021A094
        摘要：Let H be an infinite dimensional separable complex Hilbert space and B(H) be the algebra of all bounded linear operators on H. σ(T) denotes the spectrum of T∈B(H). T∈B(H) is said to satisfy property (R) if σa(T)\ σab(T)=π00(T)， where σa(T)  and σab(T) denote the approximate point spectrum and the Browder essential approximate spectrum of T respectively， π00(T)={λ∈iso σ(T):0<n(T-λI)<+∞}. A new judgement for property (R) for bounded linear operator is given. In additional， the relations between the property (R) and the hypercyclic property are considered.  
        关键词：property （R）;hypercyclic property;spectrum   
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        发布时间：2023-11-01
      • CAI Zhongbo,ZHAO Jihong,LUO Yongke
        Vol. 62, Issue 2, Pages: 181-188(2023) DOI: 10.13471/j.cnki.acta.snus.2022A005
        摘要：A class of fractional chemotaxis model is concerned， which is a generalized model of the Keller-Segel equations arising from biology in describing chemotaxis phenomenon. Based on the linear and nonlinear estimates of the heat semi-group in the pseudo-measure space， the global existence and uniqueness of self-similar solutions are established. Moreover， by applying the Lebesgue dominated convergence theorem， the asymptotic stability of self-similar solutions are also established as time tends to infinity.  
        关键词：fractional chemotaxis model;pseudo-measure space;self-similar solutions;asymptotic stability   
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