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A new tetracyclic triterpenoid from endophytic fungus Fusarium sporotrichioides

Chinese Herbal Medicines 2024年第2期16卷 231-234页

作者： Yajing Wang chunyue liu Yihui Yang Chang Li Yuehu Pei Department of Medicinal Chemistry and Natural Medicine Chemistry College of PharmacyHarbin Medical UniversityHarbin 150081China

Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological ***: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR(1H-NMR and13C-NMR) and 2D NMR(1H–1H COSY,HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD ***: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L(1), 12aacetoxy-4,4-dimethyl-24-methylene-5a-cholesta-8,14-diene-2a,3β,11β-triol(2), 12a-acetoxy-4,4-dime thyl-24-methylene-5a-cholesta-8-momoene-2a,3β,11β-triol(3), 12a-acetoxy-4,4-dimethyl-24-methy lene-5a-cholesta-8,14-diene-3β,11β-triol(4), and 12a-acetoxy-4,4-dimethyl-24-methylene-5acholesta-8-momoene-3β,11β-triol(5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 ***: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus ***. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on Hep G-2 cells than the other compounds, with IC50values of(2.8 ± 0.1) and(6.3 ± 0.3) μmol/L respectively.

关键词： antitumor Fusarium sporotrichioides integracide L tetracyclic triterpenoid 12a-acetoxy-4,4-dimethyl-24-methylene5a-cholesta-814-diene-2a,3b,11b-triol 12a-acetoxy-4,4-dimethyl-24-methylene5a-cholesta-8-momoene-2a,3b,11b-triol 12a-acetoxy-4,4-dimethyl-24-methylene5a-cholesta-8-momoene-3b,11b-triol

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1986-2018年黄土丘陵区典型小流域不同水文年水沙变化

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水土保持研究 2024年第1期31卷 126-135页

作者：刘春月信忠保秦瑞杰张满良刘晓北京林业大学水土保持学院北京100083 北京林业大学山西吉县森林生态系统国家野外科学观测研究站北京100083 黄河水利委员会天水水土保持科学试验站甘肃天水741000

[目的]探讨黄土丘陵区罗玉沟典型小流域水沙变化趋势以及不同水文年径流输沙对水土流失治理的响应差异,量化降水和人类活动对流域水沙影响的相对贡献,以期为黄土丘陵第三副区流域水土流失治理和水资源管理提供参考。[方法]基于罗玉沟流... 详细信息

[目的]探讨黄土丘陵区罗玉沟典型小流域水沙变化趋势以及不同水文年径流输沙对水土流失治理的响应差异,量化降水和人类活动对流域水沙影响的相对贡献,以期为黄土丘陵第三副区流域水土流失治理和水资源管理提供参考。[方法]基于罗玉沟流域1986—2018年的降雨、径流、输沙等数据,采用Mann-Kendall检验法、累积距平法及双累积曲线法分析流域水沙变化趋势及驱动因素。[结果]1986—2018年罗玉沟流域河流由常流河转变为季节性河流,干河日数显著上升(p<0.01),2000年以来干河日数多在300 d以上;同期,罗玉沟流域径流输沙显著下降(p<0.05),与基准期1986—1993年相比,1994—2007年减水减沙率分别为61.9%,44.3%,2008—2018年径流输沙分别减少67.5%,76.4%;在2008—2018年平水年和枯水年间罗玉沟流域输沙模数分别为(1 080.0±107.5) t/km^(2),(167.8±111.4) t/km^(2),而在暴雨频发丰水年,输沙模数仍接近4 000 t/km^(2);流域产流产沙能力降低,水沙关系发生改变,相同径流条件下输沙量减少,即流域径流含沙量水平降低,开始变清;相比降雨变化而言,人类活动是流域水沙变化的主导因素,1994—2007年人类活动对减水减沙的贡献率分别为83.3%和79.5%,而2008—2018年人类活动的贡献率分别为91.8%,94.4%,表明流域水沙变化受人类活动影响越来越大,其中,坡改梯及退耕还林还草工程是主要影响因素。[结论]因沟道治理工程建设不足,罗玉沟流域在丰水年因沟道重力侵蚀导致流域输沙仍然剧烈,因此,需要加强沟道治理进一步减少流域水土流失。

关键词：黄土高原水沙变化丰水年水土保持措施趋势分析归因分析

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基于刺槐年轮重建黄土丘陵区小流域年径流输沙研究

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生态学报 2024年第1期44卷 343-353页

作者：刘春月信忠保李宗善买尔当·克依木北京林业大学水土保持学院北京100083 北京林业大学山西吉县森林生态系统国家野外科学观测研究站北京100083 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国科学院新疆生态与地理研究所沙漠绿洲国家重点实验室乌鲁木齐830011

刺槐是广泛分布于黄土高原的典型水土保持植物。以黄土丘陵区甘肃天水吕二沟小流域为研究区,分析了刺槐径向生长过程及其对气候因子的响应,并开展了利用刺槐年轮估算小流域年径流量、年输沙量的适用性评估。研究表明:(1)吕二沟刺槐人工... 详细信息

刺槐是广泛分布于黄土高原的典型水土保持植物。以黄土丘陵区甘肃天水吕二沟小流域为研究区,分析了刺槐径向生长过程及其对气候因子的响应,并开展了利用刺槐年轮估算小流域年径流量、年输沙量的适用性评估。研究表明:(1)吕二沟刺槐人工林的径向生长随林龄呈明显的下降趋势,在幼龄林阶段(1—10 a)刺槐处于快速径向生长期((4.17±0.74)mm/a),之后逐渐下降,中龄林、成熟林、过熟林阶段(11—40 a)平均生长速率为(2.31±0.41)mm/a,较前期下降了44.60%。刺槐胸高断面积增量(BAI)在1—10 a平均以(5.46±2.13)cm^(2)/a的速度生长,在11—40 a仍保持上升趋势但年际间生长波动较大,生长速率平均为(10.80±1.95)cm^(2)/a,流域刺槐生长并未发生明显衰退。(2)刺槐的径向生长与温度多呈负相关,与降水、相对湿度及帕默尔干旱指数(PDSI)多呈正相关。其中刺槐径向生长与上年8月、9月(P<0.05)及当年7月均温、最高温呈显著负相关(P<0.01),与当年5月最低温呈显著正相关(P<0.05);与当年6月、7月降水量和上年8月、当年7月相对湿度呈显著正相关(P<0.05),与当年3月相对湿度显著负相关(P<0.05);与上年6月、上年10月—当年1月及当年3月—8月PDSI显著正相关(P<0.05),干旱胁迫明显抑制流域刺槐生长。(3)1978—2017年吕二沟流域年径流量、年输沙量呈减少趋势,年际间波动较大,存在明显丰枯阶段。流域径流输沙受降水量影响显著,且径流输沙显著正相关(P<0.001)。(4)利用刺槐年轮估算吕二沟流域年径流量、输沙量效果良好(P<0.02),方法可行。比较而言,相对自然条件下即人类干扰较少时径流输沙估算优于人类活动影响时期。利用树轮宽度反演水文过程可为缺乏水文观测资料区域提供参考。

关键词：黄土高原刺槐树木年轮气候径流输沙

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Multi-scale analysis to uncover habitat use of red-crowned cranes： Implications for conservation

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Current Zoology 2013年第5期59卷 604-617页

作者： chunyue liu Hongxing JIANG Shuqing ZHANG Chunrong LI Yunqiu HOU Fawen QIAN Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130102 China Research Institute of Forest Ecology Environment and Protection Key Laboratory of Forest Protection of State Forestry Ad- ministrationChinese Academy of Forestry Beijing 100091 China Yancheng National Nature Reserve Xinyanggang Sheyang County 224333 Jiangsu China

A multi-scale approach is essential to assess the factors that limit avian habitat use. Numerous studies have examined habitat use by the red-crowned crane, but integrated multi-scale habitat use information is lacking. We evaluated the effects of several habitat variables quantified across many spatial scales on crane use and abundance in two periods （2000 and 2009） at Yancheng National Nature Reserve, China. The natural wetlands decreased in area by 30,601 ha （-6.9%） from 2000 to 2009, pre- dominantly as a result of conversion to aquaculture ponds and farmland, and the remaining was under degradation due to expan- sion of the exotic smooth cordgrass. The cranes are focusing in on either larger patches or those that are in close proximity to each other in both years, but occupied patches had smaller size, less proximity and more regular boundaries in 2009. At landscape scales, the area percentage of common seepweed, reed ponds and paddy fields had a greater positive impact on crane presence than the area percentage of aquaculture ponds. The cranes were more abundant in patches that had a greater percent area of common seepweed and reed ponds, while the percent area of paddy fields was inversely related to crane abundance in 2009 due to changing agricultural practices. In 2009, cranes tended to use less fragmented plots in natural wetlands and more fragmented plots in anthropogenic paddy fields, which were largely associated with the huge loss and degradation of natural habitats between the two years. Management should focus on restoration of large patches of natural wetlands, and formation of a relatively stable area of large paddy field and reed pond to mitigate the loss of natural wetlands [Current Zoology 59 （5）： 604-617, 2013].

关键词： Red-crowned crane Habitat Selection Remote sensing Scale Patch Landscape

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Integrating TM and Ancillary Geographical Data with Classification Trees for Land Cover Classification of Marsh Area

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Chinese Geographical Science 2009年第2期19卷 177-185页

作者： NA Xiaodong ZHANG Shuqing ZHANG Huaiqing LI Xiaofeng YU Huan liu chunyue Northeast Institute of Geograpky and Agroecology Chinese Academy of Sciences Ckangchun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Institute of Resources Information Chinese Academy of Forestry Beijing 100091 China

The main objective of this research is to determine the capacity of land cover classification combining spec- tral and textural features of Landsat TM imagery with ancillary geographical data in wetlands of the Sanjiang Plain, Heilongjiang Province, China. Semi-variograms and Z-test value were calculated to assess the separability of grey-level co-occurrence texture measures to maximize the difference between land cover types. The degree of spatial autocorrelation showed that window sizes of 3×3 pixels and 11×11 pixels were most appropriate for Landsat TM im- age texture calculations. The texture analysis showed that co-occurrence entropy, dissimilarity, and variance texture measures, derived from the Landsat TM spectrum bands and vegetation indices provided the most significant statistical differentiation between land cover types. Subsequently, a Classification and Regression Tree (CART) algorithm was applied to three different combinations of predictors: 1) TM imagery alone (TM-only); 2) TM imagery plus image texture (TM+TXT model); and 3) all predictors including TM imagery, image texture and additional ancillary GIS in- formation (TM+TXT+GIS model). Compared with traditional Maximum Likelihood Classification (MLC) supervised classification, three classification trees predictive models reduced the overall error rate significantly. Image texture measures and ancillary geographical variables depressed the speckle noise effectively and reduced classification error rate of marsh obviously. For classification trees model making use of all available predictors, omission error rate was 12.90% and commission error rate was 10.99% for marsh. The developed method is portable, relatively easy to im- plement and should be applicable in other settings and over larger extents.

关键词： land cover classification classification trees Landsat TM ancillary geographical data marsh

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Effects of Normalized Difference Vegetation Index and Related Wavebands′ Characteristics on Detecting Spatial Heterogeneity Using Variogram-based Analysis

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Chinese Geographical Science 2012年第2期22卷 188-195页

作者： WEN Zhaofei ZHANG Ce ZHANG Shuqing DING Changhong liu chunyue PAN Xin LI Huapeng SUN Yan Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beij＇ing 100049 China Laboratory of Geographical Resources and Environmental Remote Sensing College of Geographical Sciences Harbin Normal University Harbin 150025 China Electrical and Electronic Teaching and Research Office Aviation University of Air Force Changehun 130022 China

Spatial heterogeneity is widely used in diverse applications, such as recognizing ecological process, guiding ecological restoration, managing land use, etc. Many researches have focused on the inherent scale multiplicity of spatial heterogeneity by using various environmental variables. How these variables affect their corresponding spatial heterogeneities, however, have received little attention. In this paper, we examined the effects of characteristics of normalized difference vegetation index （NDVI） and its related bands variable images, namely red and near infrared （NIR）, on their corresponding spatial heterogeneity detection based on variogram models. In a coastal wetland region, two groups of study sites with distinct fractal vegetation cover were tested and analyzed. The results show that： l） in high fractal vegetation cover （H-FVC） area, NDV! and NIR variables display a similar ability in detecting the spatial he- terogeneity caused by vegetation growing status structure; 2） in low fractal vegetation cover （L-FVC） area, the NIR and red variables outperform NDVI in the survey of soil spatial heterogeneity; and 3） generally, NIR variable is ubiquitously applicable for vegetation spatial heterogeneity investigation in different fractal vegetation covers. Moreover, as variable selection for remote sensing applications should fully take the characteristics of variables and the study object into account, the proposed variogram analysis method can make the variable selection objectively and scientifically, especially in studies related to spatial heterogeneity using remotely sensed data.

关键词： spatial variation spatial structure NDVI characteristic semivariogram model semivariogram analysis

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海洋石油平台冷放空系统设计数值模拟分析

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中国海洋平台 2024年第5期39卷 90-96,108页

作者：惠龙轩张时佳肖峰超刘春悦董博徐念念唐宇光中海油能源发展装备技术有限公司设计研发中心天津300451

以渤中13-1 WHPB井口平台为例,基于Flaresim和Fluent仿真软件,采用数值模拟方法分析WHPB平台冷放空系统的设计、辐射及气体扩散。评估冷放空管及放空头尺寸是否满足辐射和扩散的要求以及放空系统在紧急泄放下对平台的影响。根据模拟研... 详细信息

以渤中13-1 WHPB井口平台为例,基于Flaresim和Fluent仿真软件,采用数值模拟方法分析WHPB平台冷放空系统的设计、辐射及气体扩散。评估冷放空管及放空头尺寸是否满足辐射和扩散的要求以及放空系统在紧急泄放下对平台的影响。根据模拟研究分析以及与钻完井专业人员核实,该平台冷放空系统设计满足要求,可为海洋平台冷放空系统设计提供参考。

关键词：渤中13-1 WHPB井口平台冷放空系统仿真软件数值模拟

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Effect of Ultrasonic Vibration on Dealloying Corrosion of CuCrAl Alloy in H2SO4 Solutions

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材料科学与工程（中英文A版） 2011年第2X期1卷 253-257页

作者： Zhe Zhang Chaoyi Yan chunyue liu Yinfeng Xia Jianhua liu Ruijun Zhang State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China

In view of dealloying corrosion of CuCrAl alloy in acidic solution, dealloying corrosion of CuCrAl alloy in H2SO4 solution was investigated by using static immersing corrosion, and the effect of ultrasonic vibration on dealloying corrosion of the CuCrAl alloy in H2SO4 solution was studied by optical microscope and scanning electron microscope. The results show that the dechromisation corrosion occurs when CuCrAl alloy in H2SO4 solution at a certain condition, and ultrasonic vibration can shorten the dechromisation incubation time, decrease temperature and concentration of H2SO4 solution while the dechromisation occurs, and accelerate the dechromisation corrosion of the CuCrAl alloy.

关键词： H2SO4溶液 Al合金腐蚀作用 CuCr 超声振动扫描电子显微镜超声波振动光学显微镜

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双电极式磁模拟器的高空磁异常

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哈尔滨工程大学学报 2019年第6期40卷 1078-1083页

作者：刘春跃刘辉韩瑞庆段剑洁昆明船舶设备研究试验中心

为了研究双电极式磁模拟器模拟潜艇高空磁异常的有效性,本文在建立双电极式磁模拟器高空磁异常理论模型的基础上,利用搭载氦光泵磁探仪的三角翼飞机进行网格化飞行测量,验证了磁异常实测值与理论计算值在强度及曲线形态上均吻合度较高,... 详细信息

为了研究双电极式磁模拟器模拟潜艇高空磁异常的有效性,本文在建立双电极式磁模拟器高空磁异常理论模型的基础上,利用搭载氦光泵磁探仪的三角翼飞机进行网格化飞行测量,验证了磁异常实测值与理论计算值在强度及曲线形态上均吻合度较高,符合潜艇磁偶极子场特征。研究结果证明:采用双电极式磁模拟技术模拟潜艇高空磁异常特征是可行的。

关键词：磁异常磁场模拟电极拖曳缆磁偶极子潜艇磁场磁模拟器磁探测

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Expansion and Management Implications of Invasive Alien Spartina alterniflora in Yancheng Salt Marshes, China

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Open Journal of Ecology 2016年第3期6卷 113-128页

作者： chunyue liu Hongxing Jiang Shuqing Zhang Chunrong Li Xin Pan Jun Lu Yunqiu Hou Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun China Research Institute of Forest Ecology Environment and Protection Key Laboratory of Forest Protection of State Forestry Administration Chinese Academy of Forestry Beijing China Yancheng National Nature Reserve Xinyanggang Sheyang County Jiangsu China School of Electrical & Information Technology Changchun Institute of Technology Changchun China

Improved understanding of the spatial dynamics of invasive plant species is critical for effective land management and control of future invasion. The Yancheng National Nature Reserve (YNNR), an internationally important wetland, has the largest distribution of alien Spartina alterniflora in China. This alien plant was intentionally introduced for erosion prevention and dike protection in China. However, it became an aggressive competitor with native salt marsh plants in the coastal regions in China. High resolution imagery, SPOT-5, was used to map plant communities including invasive species in the south core zone of YNNR with the natural ecosystem of salt marshes in 2003, 2005 and 2008. The fuzzy set assessment method significantly improved the classification accuracies over the conventional error matrix, i.e., from 73.8%, 73.5% and 81.4% to 91.5%, 91.6% and 93.4% in 2003, 2005 and 2008, respectively. It shows a great potential for mapping invasive plant species. Phragmites australis and S. alterniflora were the most accurately mapped classes, and sparse and dense Suaeda glauca were the least accurately mapped. From 2003 to 2008, S. alterniflora increased 28.8% from 1664.1 to 2142.6 ha in area size, and more than 2.5 times from 742 to 2608 patches. The highest increase in patch number occurred within the interval between 2001 and 3000 m from the eastern baseline. This increase was dominated by small patches with area less than 200 m2. During the study period, the mean spread width was 405 ± 80.7 m in the original large patch of area over 200 ha. The eastward/seaward spread was distinctively larger than the westward/landward. The results enhance the understanding of alien plant’s invasion patterns and help improve conservation efforts.

关键词： Spartina alterniflora SPOT-5 Remote Sensing Fuzzy Set Assessment Expansion Characteristics Management Implications

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