最新刊期
      卷 61 ， 期 4 ， 2022

        Invited review

      • SHI Rui,WANG Yonggang,LI Peibo,PENG Wei,SU Weiwei
        Vol. 61, Issue 4, Pages: 1-10(2022) DOI: 10.13471/j.cnki.acta.snus.2021E032
        摘要：This article reviews the regulation mechanism of airway smooth muscle contraction， the progress on the research and treatment of cough variant asthma， the regulation mechanism of airway epithelial liquid secretion， and the progress on the effects of naringin on the airway contraction and surface liquid secretion， highlighting the potential of naringin for its clinical application.  
        关键词：naringin;airway;contraction;surface liquid secretion;regulation mechanism   
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        发布时间：2023-11-01

        Research articles

      • HE Miao,SHI Changhao,SHE Xuanjie,CHENG Ziqi,DONG Shuohan,LIU Tianhao,ZHANG Zhihao,LIU Jing
        Vol. 61, Issue 4, Pages: 11-21(2022) DOI: 10.13471/j.cnki.acta.snus.2021E002
        摘要：To explore the early stage spatial-temporal characteristics and to assess the factors of atmospheric pollution that may affect the development of coronavirus disease 2019 （COVID-19） outbreak in the Chinese Mainland in 2020， we collected the daily new cases of COVID-19 in the Municipalities and Provinces from the websites of National and Provincial Health Commission of China. The spatio-temporal characteristics of COVID-19 epidemic were studied using autocorrelation analysis and trend analysis. The Spearman's correlation coefficient for ranked data and generalized additive model were used for risk assessment of air pollutants affecting the COVID-19 epidemic of Hubei Province. Daily new cases of COVID-19 in the Chinese Mainland totaled 39 877 from January 20th to February 9th of 2020. The global Moran index values of these three weeks were 0.249， 0.307 and 0.297 （P<0.01）， respectively. There was a significant clustering phenomenon. The high incidence regions included Hunan Province， Guangdong Province， Jiangxi Province， Zhejiang Province， Anhui Province and Jiangsu Province. The epidemic hot spots were basically distributed in the area from 108° 47'-123° 10' E to 25° 31'-35° 20' N. Daily new cases of COVID-19 in Hubei Province was positively correlated with daily average concentrations of PM10， NO2 and O3 pollutants （ρ=0.515， 0.579 and 0.536，P<0.05）. The lag effects of air pollutions were existed. The relative risk （RR） values of PM2.5 and PM10 reached to maximum with lag0， the RR value of NO2 reached to maximum with lag4， and the RR value of O3 reached to maximum with lag 0~1. We estimated that a 10 μg/m3 increase in day-before NO2 daily average concentration was associated with a 32.745% （95% Confidence Interval （CI）：11.586%-57.916%） excess risk （ER） of daily new cases of COVID-19. And NO2 had a significant impact on daily new cases of COVID-19. When NO2 was introduced to PM2.5 and PM10 separately， for every 10 μg/m3 rise in NO2 daily average concentration， the ER of daily new cases of COVID-19 was 23.929% （95% CI： 4.705%-46.682%） and 24.672% （95% CI： 5.379%-47.496%）， respectively. The study showed that the southeast was the main spread direction in the early stage of COVID-19 outbreak in the Chinese Mainland in 2020. Reducing the atmospheric concentration of nitrogen dioxide in epidemic hot spots has a positive effect on epidemic prevention and control.  
        关键词：coronavirus disease 2019（COVID-19）;early stage of outbreak in 2020;spatial-temporal characteristics;risk assessment   
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        发布时间：2023-11-01
      • QIAO Xueting,ZHANG Juanjuan,LI Wenbin,TONG Sen,LI Buhang,YANG Qiong,XU Hualin,CHEN Ting,YU Shixiao
        Vol. 61, Issue 4, Pages: 22-30(2022) DOI: 10.13471/j.cnki.acta.snus.2021E014
        摘要：The establishment of the Neilingding Island Nature Reserve has gradually restored the vegetation on the island. In this paper， the vegetation of Neilingding Island， which belongs to Guangdong Neilingding Island-Futian National Nature Reserve， was taken as the research object. Based on the remote sensing images obtained by UAV technology， combined with the field investigation， vegetation types on Neilingding Island were classified and the vegetation map was drawn. Four main results were obtained： （1） The main natural vegetation types include the subtropical evergreen broad-leaved forest， the subtropical coniferous and broad-leaved mixed forest， the subtropical evergreen shrub， the subtropical bamboo forest. In addition， the coastal sand shrub， mangrove also distribute in this island. （2） The subtropical evergreen broad-leaved forest is the climatic climax in this region， accounting for 46.97% of the vegetation distribution area， and occupies the absolute dominant position. Microcos paniculata and Macaranga tanarius， the dominant species in the community， are the main food source plants for Macaca mulatta， the main protected species on Neilingding Island. In mangrove， only a small area of Aegiceras corniculatum was found on the east Dongwanzui and the east coast of Heishawan. （3） The main types of artificial vegetation are： Acacia confusa， Macaranga tanarius， Cathuarina equisetifolia， Heteropanax fragrans， Cocos nucifera， Hibiscus hamabo， Litchi chinensis and Dimocarpus longan，Acacia confusa is the most important artificial vegetation. It accounts for 29.80% of the vegetation distribution area， and is also one of the main food sources of Macaca mulatta. （4） Mikania micrantha and Byttneria grandifolia are the main invasive plants on Neilingding Island. They result in a serious vegetation degradation. Despite manual removal and chemical control， they are still wreak havoc on this island every year. UAV remote sensing image provides new means and ideas for island vegetation survey and mapping， and the digital vegetation map drawn by GIS can provide important scientific basis for rational information management of the vegetation in the reserve.  
        关键词：Neilingding Island;UAV remote sensing image;vegetation classification;vegetation types;natural vegetation;artificial vegetation;vegetation mapping   
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        发布时间：2023-11-01
      • JIANG Shujiao,GUO Guangyu,JIANG Lu,GUO Qiang,JIA Fenglong
        Vol. 61, Issue 4, Pages: 31-40(2022) DOI: 10.13471/j.cnki.acta.snus.2021E025
        摘要：A total of 84 species of true water beetles were reported from Dapeng Peninsula， Shenzhen， of which 23 species assigned to Dytiscidae， 3 species to Noteridae， 1 species to Haliplidae， 3 species to Gyrinidae， 1 species to Hydraenidae， 1 species to Georissidae， 1 species to Hydrochidae， and 51 species to Hydrophilidae. Forty-nine species only collected in stagnant fresh water accounting for 58.3%； 8 species only found in sides of streams or rivers accounting for 9.5%； 7 species on wet stones and 6 species were in decaying plants； 14 species were found at two or more kinds environments accounting for 16.7%. Twenty-five species were collected with light trap accounting for 29.8%. Genus Noteropagus was firstly reported from China. Helochares dentalus d'Orchymont， Patrus coomani （Peschet） and Neohydrocoptus rubescens （Clark） were reported for the first time to China. Genus Georissus was also recorded for the first time from China Mainland. RDA analysis showed that there was a strong correlation between most of the water beetles and stagnant fresh water in the Dapeng Peninsula， and some water beetles had a strong correlation with running water. Few species were strongly correlated with riverside， decaying plants， wet rock and wet grassland. The distribution pattern shows the evolution of aquatic beetles after many changes in their living environment.  
        关键词：water beetles;biodiversity;Dapeng Peninsula   
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        发布时间：2023-11-01
      • YANG Yan,XIA Jun,WANG Qing,HE Yinglin,ZHANG Yong,ZHAO Huihong,YANG Huirong
        Vol. 61, Issue 4, Pages: 41-48(2022) DOI: 10.13471/j.cnki.acta.snus.2021E031
        摘要：Epinephelus coioides is a marine fish with high economic value. How to improve the production characteristics of E. coioides has always been one of the focuses of scientific research. Myostatin（mstn） is an important transforming factor in regulating muscle growth. In this study， we investigated the effects of mstn on proliferation and differentiation of muscle cells and its related genes expression. The subcellular localization of Mstn showed that Mstn distributed in the cytoplasm of E. coioides. The A value of muscle primary cells stimulated by Mstn recombinant protein for 1-5 days was measured by enzyme labeling instrument. It was found that the growth of cells in the experimental group slowed down significantly， and the difference of cell activity further expanded with the increase of treatment time. Primary muscle cells were stimulated with Mstn recombinant protein. The effects of Mstn recombinant protein on mstn signal pathway and downstream related genes were detected by RT-qPCR. The results showed that the expression of p21， smad3 and mrf4 mRNA increased gradually with the increase of treatment concentration， and there was no significant difference in the expression of smad3 and mrf4； When the treatment concentrations were 100 and 1 000 nmol/L， there was a significant difference in p21； With the increase of treatment concentration， the expression of myod and myog mRNA decreased， but the downward trend of myod mRNA was not significant. Myog mRNA decreased significantly， and there was a significant difference when the treatment concentration was 100 and 1 000 nmol/L. This study revealed that Mstn is localized in the cytoplasm of E. coioides GS； the recombinant Mstn protein up-regulates the expression of smad3 and mrf4， and down-regulates the expression of myod and myog to promote cell differentiation； at the same time， the recombinant Mstn protein can up-regulate the expression of p21 and inhibit the cell proliferation. The study verified the biological function of Mstn in the process of muscle development， and provided a theoretical foundation for the subsequent in-depth study of the effect of mstn on fish muscle development.  
        关键词：mstn;Epinephelus coioides;muscle;expression analysis   
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        发布时间：2023-11-01
      • LU Songsong,ZHAO Xiaxia,QI Chongxia,DU Yuwei
        Vol. 61, Issue 4, Pages: 49-59(2022) DOI: 10.13471/j.cnki.acta.snus.2021E018
        摘要：The study was aimed to reveal the mechanism of elevated hemoglobin oxygen affinity of Plateau zokor （Eospalax baileyi）.By using a comparative genomic and transcriptomic analysis of the α and β gene clusters in the plateau zokor to characterize the changes in the size and membership composition of the α and β gene families within the Spalacidae， the study evaluated the evolutionary changes in the developmental regulation of gene expression of the plateau zokor and explored the potential impact of positive selection sites on protein structure and function. The results showed that the plateau zokor α and β gene clusters contain three α （5ʹ-αE， αA， αQ-3ʹ） and seven β （5ʹ-ε， γ， γ1， γ2， σ （pesudo）， β1， β2 （pesudo）-3ʹ） genes respectively；in addition to the conventional adult expression genes αA and β1， adult plateau zokor expressed an extra embryonic αE gene；the twelve amino acid mutations on heme “pocket” opening of β1 subunit might be able to increase the stability and hydrophilicity of the region， and slightly increases the volume of the pocket （active center）. The results also suggested that the abnormally high oxygen affinity of plateau zokor might result from the expression of embryonic αE gene in adults；the increased stability of αE and β1 subunits and the decrease of αA subunit stability may lead to accumulation of αE type Hb （αEβ1）2 to a concentration similar to αA type （αAβ1）2. It was the first report that the αE gene is highly expressed in adult mammals， this phenomenon may be induced by extreme low oxygen environment， or it may be caused by changes in the genetic basis of the αE gene regulatory region. The specific mechanism needs further study.  
        关键词：Eospalax baileyi;hemoglobin;oxygen affinity;gene expression   
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        发布时间：2023-11-01
      • CHEN Ruolan,LI Ziyang,WU Huizhen,LUO Yimeng,SHE Zhigang,XIONG Yahong,LI Chunyuan
        Vol. 61, Issue 4, Pages: 60-64(2022) DOI: 10.13471/j.cnki.acta.snus.2021C011
        摘要：The metabolites of an endophytic fungus Pseudallescheria boydii L32 derived from the mangrove plant Myoporum bontioides A.Gray were studied. The monomeric compounds were isolated from the fermentation product by the modern chromatography technology. The structures were determined by spectral analysis. The antibacterial activity was tested via the dilution method. Ten metabolites were purified including 2，2′-oxybis（1，4）-di-tert-butylbenzene （1），livistone B （2），simplicildone A （3），simplicildone B （4），botryorhodine B （5），（‒）-regiolone （6），citreoanthrasteroid B （7），stigmast-4-en-3-one （8），succinic acid （9） and oxalic acid （10）. Compounds 1，3，4，5，7 and 8 were isolated from Pseudallescheria sp. for the first time. Compounds 1，4，5 and 6 showed antibacterial activity against Escherichia coli with O6 serotype and compounds 1 and 5 showed antibacterial activity against E.coli with O78 serotype with MIC values of 50，12.5，25，100，100，100 μg/mL， respectively.  
        关键词：mangrove fungus;Pseudallescheria boydii;metabolites;antibacterial activity   
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        发布时间：2023-11-01
      • XIAO Ze′en,LIN Shao′e,SHE Zhigang,LU Yongjun,TAN Zhen,LIU Yonghong
        Vol. 61, Issue 4, Pages: 65-69(2022) DOI: 10.13471/j.cnki.acta.snus.2021C013
        摘要：The mangrove endophytic fungus Aspergillus sp. HNY16-5C was fermented by using rice medium. The metabolites were isolated by the chromatography technology. Six nitrogen-contained compounds were obtained. By analyzing MS and NMR spectroscopic data，their structures were identified as brevianamide K（1）， brevianamide V（2）， （R）-brevianamide Q（3）， （R）-brevianamide R（4）， （±）-asperginulin A（5） and brevianamide M（6）， respectively. Compound 1 exhibited potent inhibitory effect against Mycobacterium tuberculosis protein tyrosine phosphatase B（MptpB） with IC50 values of （7.07 ± 2.76） μmol/L.  
        关键词：mangrove endophytic fungus;secondary metabolites;nitrogen-contained compounds;MptpB   
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        发布时间：2023-11-01
      • LI Yongyi,CAI Jinxuan,FANG Yue,LI Jiaxin,ZHONG Xiaoqian,WEI Xia,LIU Bingxin,ZHANG Cuixian
        Vol. 61, Issue 4, Pages: 70-78(2022) DOI: 10.13471/j.cnki.acta.snus.2020C015
        摘要：In order to research the novel compounds from the soft coral-associated symbiotic and epiphytic fungus Aspergillus sp.EGF15-0-3， the column chroma tography with SiO2， ODS， Sephdex LH-20， RP-HPLC， and etc. were carried out， and two xanthones， five anthraquinones and two dimers were isolated from PDA medium. According to the （HR）ESI-MS， 1D and 2D NMR， ORD， UV， and comparison with the literatures， their structures were determined as eurorubrin （1）， anhydro flavomannin-quinone-6，6′-dimethyl ether （2）， asperflavin （3）， 8-O-methyl ether-asperflavin （4）， emodin （5）， 1-O-methyl emodin （6）， physcion （7）， rubrocristin （8）， and 3-O-（α-D-ribofuranosyl）-questin （9）. 1 consisted of two asperflavins， and 2 was a heterodimer of torosachrysone and emodin， and was a firstly natural product. 1， 2， 4 and 9 were obtained from genus of Aspergillus for the first time.  
        关键词：Aspergillus sp.EGF15-0-3;xanthones;anthraquinone;dimers   
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        发布时间：2023-11-01
      • MA Yun
        Vol. 61, Issue 4, Pages: 79-84(2022) DOI: 10.13471/j.cnki.acta.snus.2021C015
        摘要：Acidic substances are usually added to the synthesis of UiO-66 as acidity regulators. UiO-66 was prepared by hydrothermal method using zirconium chloride as its precursor， terephthalic acid as organic ligand and N，N- dimethylformamide as a solvent. The effect of acidity regulator on the structure and properties of UiO-66 was investigated by adding different volumes of acetic acid into the precursor solution. The samples were characterized and analyzed by thermogravimetric analysis， infrared spectroscopy， X-ray diffraction， scanning electron microscopy， transmission electron microscopy， and nitrogen adsorption and desorption. The visible light catalytic degradation efficiency of UiO-66 was investigated using ceftriaxone sodium as the degradation pollutant. The results showed that the structure of UiO-66 added with acetic acid was more orderly and had stronger absorptive capacity in visible light region. When no acetic acid was added， UiO-66 was a small circular particle with a specific surface area of 695.435 8 m²/g. The degradation rate of ceftriaxone sodium by visible light irradiation for 120 min was 29.46%. With the increase of acetic acid content， the particle size of UiO-66 gradually increased. When n（ZrCl4）∶n（H2BDC）∶n（HAc） = 1∶1∶200， UiO-66 had a more regular octahedral structure， and its specific surface area was as high as 1 270.821 1 m²/g， and the degradation rate of ceftriaxone sodium under visible light irradiation for 120 min was 50.77%.  
        关键词：UiO-66;acetic acid;regulator;synthesis;cephalosporin   
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        发布时间：2023-11-01
      • LIU Jun,TANG Xiaowen,PAN Yu,LIU Fang,ZHANG Xuejiao,MA Hongyuan,WANG Zuocheng
        Vol. 61, Issue 4, Pages: 85-94(2022) DOI: 10.13471/j.cnki.acta.snus.2020C023
        摘要：The optical isomerization of S-type amphoteric proline（S-Pro） is investigated by using the M06-2X and MN15 methods of density functional theory and the SMD model method of self-consistent reaction field theory. Firstly， the reaction channels of S-Pro optically isomerism are investigated after S-Pro isomerized the neutral imino acids， α-H is extracted by hydroxyl anion （water clusters）， and the proton of water molecule（clusters） is extracted by proline-carbon anion. Then， the reaction channels of S-Pro optically isomerism are investigated， in which α-H of S-Pro is directly extracted by hydroxyl anion （water clusters） and the proton of water molecule （clusters） is extracted by proline-carbon anion. The calculation of the potential energy surface shows that the channel of α-H extraction by hydroxyl anion （water clusters） is the most advantageous after S-Pro isomerized the neutral imino acids， and the free energy barrier of the rate-determining step is between 46. 9 and 59. 1 kJ·mol-1. The reaction channel of the hydroxyl anion water molecule clusters directly extracting the α-H of amphoteric S-Pro is the inferior channel， and the free energy barrier of the rate-determining step is 70.8 kJ·mol-1. The results show that the racemization of proline would proceed gently in alkaline environment.  
        关键词：proline;hydroxyl anion;water cluster;density functional theory;self-consistent reaction field theory;optical isomerization;transient state;energy barrier   
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        发布时间：2023-11-01
      • LI Shaoheng ,CHEN Jianyao ,CENDÓN I Dioni ,CHEN Zongyu ,HU Shuiming ,YANG Guomin ,SHIMIZU Yuta ,FREUNDT Florian ,JIN Guangzhe ,WU Ruiqin ,GAO Lei ,LIANG Zuobing ,GONG Rouyan ,WU Qirui ,TIAN Di 
        Vol. 61, Issue 4, Pages: 95-103(2022) DOI: 10.13471/j.cnki.acta.snus.2021D059
        摘要：Groundwater age is an important hydrogeological parameter， associated closely with indentification of groundwater recharge sources， groundwater renewability， groundwater solute migration， and reconstruction of palaeoclimatic signals. In this paper， nineteen groundwater samples were collected to analyze 3H， 4He， 13C， 14C from both middle and deep layers of Leizhou Peninsula . Based on the Han-Plummer graphic method and isotope correction model， the apparent age of groundwater was found ranging from 1 037 aBP to 40 310 aBP with approximately half of sampling sites exceeding 10 000 aBP， and increasing gradually from the recharge area in the Shimaoling and Luogangling to the discharge area in the coastal zone. The 4He isotope content in groundwater samples has a significant positive correlation with the 14C age， and the groundwater age can thus be roughly estimated based on the accumulation rate of 4He isotope. In addition， three stages were classified for the relationship between electrical conductivity （EC） and 14C corrected age， yielding an obvious linearity when the apparent age was younger than 6800 aBP， which could then be used to estimate groundwater age with a known EC.  
        关键词：Leizhou Peninsula;groundwater age;isotope;14C dating;4He dating   
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        发布时间：2023-11-01
      • LIANG Junyi,WANG Donghai,ZHANG Yu,YAO Lebao
        Vol. 61, Issue 4, Pages: 104-118(2022) DOI: 10.13471/j.cnki.acta.snus.2021D019
        摘要：The WRF model and the GSI assimilation system were used to build an assimilation prediction system regarding problems of data application and forecasting effect between the 3DVar data assimilation and the 3DEnVar（Hybrid） data assimilation. Based on this system， three tests of comparative experiments were designed to perform simulation analysis and assessment of these two data assimilation methods on a case of heavy rain process caused by Typhoon "Bailu" in August 2019. The results show that： 1） In the scheme of using 3DVar assimilation with two nested domains， there is an advantage in simulating the approximate distribution of rainfall； and it can capture the location of the light rain and moderate rain.2） Using 3DEnVar （Hybrid） assimilation with two nested domains can effectively improve the accuracy of the center position of typhoon rainstorms and the forecasted positions are closer to the actual situation. 3） The 3DEnVar（Hybrid） assimilation has obvious flow dependence on the background field； meanwhile， the simulations of related tactics such as wind vector， temperature， and humidity that form heavy rainfall are more accurate.  
        关键词：3DEnVar（Hybrid） data assimilation;3DVar data assimilation;WRF-GSI system;typhoon rainfall;typhoon Bailu   
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        发布时间：2023-11-01
      • CHEN Tong,LUO Yinping,CHEN Jincai,LIU Yonghong
        Vol. 61, Issue 4, Pages: 119-132(2022) DOI: 10.13471/j.cnki.acta.snus.2021B052
        摘要：Based on the data from field observations， a numerical model of particle diffusion and deposition in a real built-up area with viaduct was constructed. The traffic-related particle dispersion during different time periods was studied. The characteristics of flow field and pollutant dispersion were analyzed under different wind directions， and the impacts of the viaduct were also discussed. The bend obstructed incoming wind from entering the middle of the street canyon， which was the main cause of serious pollution in the street canyon in parallel windward. The intersection with fewer buildings on the southeast forced the east wind to enter the north and west side street canyon. Particles in the north side street canyon were only distributed in the middle of the road， greatly reducing the pollution exposure of residents on both sides. The flow field and particle distribution at local locations （such as bends and intersections） were sensitive to small changes in incoming wind direction. Under the high street shape factor， the particle concentrations near the upper part of buildings on both sides increased sharply or maintained a high level， which was up to 84% of the pedestrian breathing height and an order of magnitude higher than that in the same position under parallel wind. The impacts of viaduct settings on the flow field and particle distributions in different street canyons were different. When vertical inflow occurred， the vortex center in lower stepped street canyon was above the viaduct， and particles gathered on the leeward side building； the vortex center in upper stepped street canyon was at the bottom of the viaduct， and particles accumulated under the viaduct.  
        关键词：urban built-up area;viaduct;particles;dispersion modeling   
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        发布时间：2023-11-01
      • LI Risheng,ZHANG Chengbo,YANG Ming,WANG Xi,LIU Fengtao
        Vol. 61, Issue 4, Pages: 133-141(2022) DOI: 10.13471/j.cnki.acta.snus.2021B045
        摘要：The feasibility of using microbial induced carbonate precipitation （MICP） to improve the strength of cement soil in Nansha District of Guangzhou is studied. The unconfined compressive strength of the bacteria solution group cement soil， made by the mixed solution of bacteria solution and urea， is compared with the control group and the medium group. The effect of bacteria on the microstructure of cement soil is studied by ion concentration monitoring， XRD， SEM and mercury intrusion test， and the mechanism of strength improvement is discussed. The experimental results show that the compressive strength of 7 days， 14 days and 28 days in the bacteria solution group is 91.3%， 53.4% and 45.3% higher than that in the control group respectively， and the improvement range decreases with the increase of curing time. The medium and urea have negative effects on the strength of cement soil. Sporosarcina pasteurii hydrolyzes urea and provides nucleation site in the bacteria solution group cement soil， which promotes a large number of free Ca2+ to transform into calcium mineral precipitation， generates more calcite and hydrated calcium silicate （C-S-H）， reduces the pore volume and pore size， makes the internal particle connection and spatial structure of cement soil more compact， thus improving the strength of cement soil.  
        关键词：cement soil;MICP;urea hydrolysis;microstructure   
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        发布时间：2023-11-01
      • WEI Shunxiang,WU Haibo,CHEN Jiupeng,LIU Liang,XIONG Binzhou,XU Yangyang
        Vol. 61, Issue 4, Pages: 142-150(2022) DOI: 10.13471/j.cnki.acta.snus.2020B149
        摘要：Joint space trajectory planning is one of the important contents of robot motion control. In order to combine Cartesian space trajectory planning with joint space trajectory planning， this paper proposes a new type of bionic foot trajectory， and uses three different methods： equidistant points， second type Chebyshev points and isochronous points. The foot trajectory is discretely sampled and the position of the interpolation point is determined， and the interpolation point is mapped to the joint space to control the joint of the robot. Firstly， the fifth-degree polynomial is used to plan the joint space trajectory， and the Hermite polynomial curve is constructed to estimate the angular velocity and angular acceleration of the interpolation point， and the joint space trajectory curve is obtained. The virtual prototype is simulated and the single-leg physical prototype experiment is analyzed， and the fit between the actual curve and the designed foot trajectory is analyzed， and the trajectory curve based on the isochronous point interpolation and the planned composite foot trajectory curve are obtained. The degree of fitting is higher； the curve of angular velocity and angular acceleration estimation using the Hermite polynomial estimation method not only has a higher degree of fitting， but also has a smoother trajectory， reduced angular acceleration mutations， and better kinematics performance.  
        关键词：quadruped robot;trajectory planning;Cartesian space;joint space;isochronous point   
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        发布时间：2023-11-01
      • ZHANG Wenhui,LIU Ting
        Vol. 61, Issue 4, Pages: 151-159(2022) DOI: 10.13471/j.cnki.acta.snus.2020A023
        摘要：n-Ding modules are investigated under the formal lower triangular matrix ring T=A0UB ， where A and B are rings， U is a (B,A)-bimodule. It is proved that （i） If UA has finite flat dimension， BU is flat and M=M1M2φM is a n-Ding projective left T-module， then M1 is a (n-1)-Ding projective left A-module， φM is a monomorphism， and M2/Im φM is a n-Ding projective left B-module；（ii） If T is a right coherent ring， BU is flat， UA is finitely presented and has finite projective dimension and W=(W1,W2)φW is a n-Ding injective right T-module， then W1 is a (n-1)-Ding injective right A-module， φW̃ is an epimorphism， and KerφW̃ is a n-Ding injective right B-module.  
        关键词：formal lower triangular matrix ring;n-Ding projective module;n-Ding injective module   
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        发布时间：2023-11-01
      • WU Yilin,XIAO Huaxi,LI Wanyi,CHEN Guoming,ZHANG Qian,LIU Yu
        Vol. 61, Issue 4, Pages: 160-169(2022) DOI: 10.13471/j.cnki.acta.snus.2021A008
        摘要：An automatic quality inspection system， aiming to identify potential product defects， is essential for the production of solar cells. But few papers focus on the detection of back electrodes in solar cells， for which a complete algorithm is proposed to segment back electrodes and check for defects on them. Firstly， coarse and fine positions of electrodes are obtained using the edge intensity projection and template matching method. Secondly， the edge of electrodes is extracted by the threshold method and seed growing method. Thirdly， an edge-to-region method is adopted to generate a closed region with edge points. Finally， a method is designed to judge whether there are defects in electrodes or not. To verify the performance of the proposed method， an experiment is carried out. From the experiment result， the proposed segmentation method for electrodes outperforms the four famous methods implemented in the experiment.  
        关键词：machine vision;defect detection;image segmentation;solar cell   
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        发布时间：2023-11-01
      • MA Fei,ZHANG Jianhua,LIU Hongzhe
        Vol. 61, Issue 4, Pages: 170-177(2022) DOI: 10.13471/j.cnki.acta.snus.2020A029
        摘要：Let Algℒ be a completely distributive commutative subspace lattice algebra，f be a nonlinear generalized Lie derivation on Algℒ with an associated nonlinear map d.Then f and d are the sum of an additive generalized derivation and a map into its center sending each commutator to zero，respectively.  
        关键词：completely distributive commutative subspace lattice algebra;nonlinear generalized Lie derivation;generalized derivation   
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        发布时间：2023-11-01
      • DING Zongpeng
        Vol. 61, Issue 4, Pages: 178-182(2022) DOI: 10.13471/j.cnki.acta.snus.2020A052
        摘要：The inverse signed edge domination number of the graph G is studied.Some new upper bounds of the inverse signed edge domination number of general graphs are given， and these upper bounds are proved to be sharp.  
        关键词：upper bound;inverse signed edge dominating function;inverse signed edge domination number   
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        发布时间：2023-11-01
      • DONG Fangfang,PEI Ruichang
        Vol. 61, Issue 4, Pages: 183-188(2022) DOI: 10.13471/j.cnki.acta.snus.2020A056
        摘要：The concepts of transposition for unitary system， generalized orthonormal and induction sequence are introduced.And the relationship between generalized frame transform and orthogonal projection is studied. Finally， the necessary and sufficient conditions of generalized tight frames vectors and the important conclusion about their induction sequence are obtained.  
        关键词：Hilbert K-module;unitary system;transposition;generalized tight frame vector;induction sequence   
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