分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
摘要： Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past. The Iraqi Kurdistan Region (IKR) is located in the north of Iraq, which has also suffered from extreme drought. In this study, the drought severity status in Sulaimaniyah Province, one of four provinces of the IKR, was investigated for the years from 1998 to 2017. Thus, Landsat time series dataset, including 40 images, were downloaded and used in this study. The Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) were utilized as spectral-based drought indices and the Standardized Precipitation Index (SPI) was employed as a meteorological-based drought index, to assess the drought severity and analyse the changes of vegetative cover and water bodies. The study area experienced precipitation deficiency and severe drought in 1999, 2000, 2008, 2009, and 2012. Study findings also revealed a drop in the vegetative cover by 33.3% in the year 2000. Furthermore, the most significant shrinkage in water bodies was observed in the Lake Darbandikhan (LDK), which lost 40.5% of its total surface area in 2009. The statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK (correlation coefficients of 0.92 and 0.72, respectively). The relationship between SPI and NDVI-based vegetation cover was positive but not significant. Low precipitation did not always correspond to vegetative drought; the delay of the effect of precipitation on NDVI was one year.
分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
Tahani K BAIT SUWAILAM
Abdulrahim M AL-ISMAILI
Nasser A AL-AZRI
L H Janitha JEEWANTHA
Hemesiri KOTAGAMA
摘要： Seawater greenhouse (SWGH) is a technology established to overcome issues related to open field cultivation in arid areas, such as the high ambient temperature and the shortage of freshwater. It adopts the humidification-dehumidification concept where evaporated moisture from a saline water source is condensed to produce freshwater within the greenhouse body. Various condenser designs are adopted to increase freshwater production in order to meet the irrigation demand. The aim of this study was to experimentally investigate the practicality of using the packed-type direct contact condenser in the SWGH to produce more freshwater at low costs, simple design and high efficiency, and to explore the impact of the manipulating six operational variables (inlet air temperature of the humidifier, air mass flowrate of the humidifier, inlet water temperature of the humidifier, water mass flowrate of the humidifier, inlet water temperature of the dehumidifier and water mass flowrate of the dehumidifier) on freshwater condensation rate. For this purpose, a direct contact condenser was designed and manufactured. Sixty-four full factorial experiments were conducted to study the effect of the six operational variables. Each variable was operated at two levels (high and low flowrate), and each experiment lasted for 10 min and followed by a 30-min waiting time. Results showed that freshwater production varied between 0.257 and 2.590 L for every 10 min. When using Minitab statistical software to investigate the significant variables that contributed to the maximum freshwater production, it was found that the inlet air temperature of the humidifier had the greatest influence, followed by the inlet water temperature of the humidifier; the former had a negative impact while the latter had a positive impact on freshwater production. The response optimizer tool revealed that the optimal combination of variables contributed to maximize freshwater production when all variables were in the high mode and the inlet air temperature of the humidifier was in the low mode. The comparison between the old plastic condenser and the new proposed direct contact condenser showed that the latter can produce 75.9 times more freshwater at the same condenser volume.
分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
Abdulrahim M AL-ISMAILI
Moustafa A FADEL
Hemantha JAYASURIYA
L H Janitha JEEWANTHA
Adel AL-MAHDOURI
Talal AL-SHUKEILI
摘要： This study aimed to explore the potential of developing a novel cooling system combining a greenhouse and an earth-tube heat exchanger (ETHE). In this system, greenhouse air is circulated through the underneath soil mass to use the deep-soil cooling effect. This was achieved through the following steps. First, soil temperature profile inside and outside the cultivated greenhouse was monitored for almost one year to study the possibility of using deep-soil coldness for cooling the greenhouse air. Second, a prototype ETHE was built to practically investigate the potential reduction in air temperature as the air flows inside the deep earth pipes. Third, a prototype greenhouse was erected to study the ETHE concept. Results from the first experiment revealed that soil temperature at a soil depth of 2.5 m inside the greenhouse offers good conditions to bury the ETHE. The soil temperature at this soil depth was below the maximum temperature (32°C) that most greenhouse crops can withstand. Results from the prototype ETHE showed a slight reduction in air temperature as it passed through the pipes. From the prototype of the integrated greenhouse and ETHE system, reduction in air temperature was observed as the air passed through the ETHE pipes. At night, the air was heated up across the ETHE pipes, indicating that the ETHE was working as a heater. We concluded from this study that greenhouses in arid climates can be cooled using the ETHE concept which would save a large amount of water that would otherwise be consumed in the evaporative coolers. Further investigations are highly encouraged.
分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
摘要： High temperature and humidity can be controlled in greenhouses by using mechanical refrigeration cooling system such as air conditioner (AC) in warm and humid regions. This study aims to evaluate the techno-financial aspects of the AC-cooled greenhouse as compared to the evaporative cooled (EV-cooled) greenhouse in winter and summer seasons. Two quonset single-span prototype greenhouses were built in the Agriculture Experiment Station of Sultan Qaboos University, Oman, with dimensions of 6.0 m long and 3.0 m wide. The AC-cooled greenhouse was covered by a rockwool insulated polyethylene plastic sheet and light emitting diodes (LED) lights were used as a source of light, while the EV-cooled greenhouse was covered by a transparent polyethylene sheet and sunlight was used as light source. Three cultivars of high-value lettuce were grown for experimentation. To evaluate the technical efficiency of greenhouse performance, we conducted measures on land use efficiency (LUE), water use efficiency (WUE), gross water use efficiency (GWUE) and energy use efficiency (EUE). Financial analysis was conducted to compare the profitability of both greenhouses. The results showed that the LUE in winter were 10.10 and 14.50 kg/m2 for the AC- and EV-cooled greenhouses, respectively. However, the values reduced near to 6.80 kg/m2 in both greenhouses in summer. The WUE of the AC-cooled greenhouse was higher than that of the EV-cooled greenhouse by 3.8% in winter and 26.8% in summer. The GWUE was used to measure the total yield to the total greenhouse water consumption including irrigation and cooling water; it was higher in the AC-cooled greenhouse than in the EV-cooled greenhouse in both summer and winter seasons by almost 98.0%–99.4%. The EUE in the EV-cooled greenhouse was higher in both seasons. Financial analysis showed that in winter, gross return, net return and benefit-to-cost ratio were better in the EV-cooled greenhouse, while in summer, those were higher in the AC-cooled greenhouse. The values of internal rate of return in the AC- and EV-cooled greenhouses were 63.4% and 129.3%, respectively. In both greenhouses, lettuce investment was highly sensitive to changes in price, yield and energy cost. The financial performance of the AC-cooled greenhouse in summer was better than that of the EV-cooled greenhouse and the pattern was opposite in winter. Finally, more studies on the optimum LED light intensity for any particular crop have to be conducted over different growing seasons in order to enhance the yield quantity and quality of crop.
分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
摘要： Groundwater forms the main freshwater supply in arid and semi-arid areas, and contamination of this precious resource is complicated by the slow rate of recharge in these areas. Nitrate contamination of groundwater is a global water quality problem, as it entails threat to human health as well as aquatic ecosystems. Source identification of contamination is the cornerstone and a prerequisite for any effective management program of water quality. Stable isotope composition of the dissolved nitrate (δ15N-NO3– and δ18O-NO3–) has been applied to identify NO3– sources and the main transformation processes in the upper aquifer system (A1/2, A4, and B2/A7 aquifers) in the Wadi Shueib catchment area, Jordan. Moreover, the stable isotope compositions of the groundwater (δ2H-H2O and δ18O-H2O) in conjunction with the groundwater hydrochemistry were integrated to investigate the origin and evolution of the groundwater. Results revealed that groundwater in the study area is fresh and hard-very hard water, and mainly a Ca-Mg-Cl type. NO3– concentration was in the range of 7.0–74.0 mg/L with an average of 37.0 mg/L. Most of the samples showed concentration higher than the natural background concentration of NO3– (5.0–10.0 mg/L). The δ2H-H2O and δ18O-H2O values indicated that the groundwater is meteoric, and of Mediterranean origin, with a strong evaporation effect. The δ15N-NO3– values ranged between 6.0‰ and 11.3‰ with an average of 8.7‰, and the δ18O-NO3– values ranged between 1.6‰ and 5.9‰ with an average of 3.4‰. These values are in conformity with the stable isotope composition of nitrate derived the nitrification of wastewater/manure, and soil NH4. Nitrification and denitrification are the main transformation processes affecting nitrogen species. Statistical analysis revealed no significant differences in the δ2H-H2O and δ18O-H2O values, and δ15N-NO3– and δ18O-NO3– values for the three aquifers (A1/2, A4, and B2/A7), indicating that the groundwater of these aquifers has the same origin, and a common source of pollution.
分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
摘要： Snow cover is an important water source for vegetation growth in arid and semi-arid areas, and grassland phenology provides valuable information on the response of terrestrial ecosystems to climate change. The Mongolian Plateau features both abundant snow cover resources and typical grassland ecosystems. In recent years, with the intensification of global climate change, the snow cover on the Mongolian Plateau has changed correspondingly, with resulting effects on vegetation growth. In this study, using MOD10A1 snow cover data and MOD13A1 Normalized Difference Vegetation Index (NDVI) data combined with remote sensing (RS) and geographic information system (GIS) techniques, we analyzed the spatiotemporal changes in snow cover and grassland phenology on the Mongolian Plateau from 2001 to 2018. The correlation analysis and grey relation analysis were used to determine the influence of snow cover parameters (snow cover fraction (SCF), snow cover duration (SCD), snow cover onset date (SCOD), and snow cover end date (SCED)) on different types of grassland vegetation. The results showed wide snow cover areas, an early start time, a late end time, and a long duration of snow cover over the northern Mongolian Plateau. Additionally, a late start, an early end, and a short duration were observed for grassland phenology, but the southern area showed the opposite trend. The SCF decreased at an annual rate of 0.33%. The SCD was shortened at an annual rate of 0.57 d. The SCOD and SCED in more than half of the study area advanced at annual rates of 5.33 and 5.74 DOY (day of year), respectively. For grassland phenology, the start of the growing season (SOS) advanced at an annual rate of 0.03 DOY, the end of the growing season (EOS) was delayed at an annual rate of 0.14 DOY, and the length of the growing season (LOS) was prolonged at an annual rate of 0.17 d. The SCF, SCD, and SCED in the snow season were significantly positively correlated with the SOS and negatively correlated with the EOS and LOS. The SCOD was significantly negatively correlated with the SOS and positively correlated with the EOS and LOS. The SCD and SCF can directly affect the SOS of grassland vegetation, while the EOS and LOS were obviously influenced by the SCOD and SCED. This study provides a scientific basis for exploring the response trends of alpine vegetation to global climate change.
分类： 地球科学 >> 地理学 提交时间： 2021-04-30 合作期刊: 《干旱区科学》
摘要： Snow avalanches are a common natural hazard in many countries with seasonally snow-covered mountains. The avalanche hazard varies with snow avalanche type in different snow climate regions and at different times. The ability to understand the characteristics of avalanche activity and hazards of different snow avalanche types is a prerequisite for improving avalanche disaster management in the mid-altitude region of the Central Tianshan Mountains. In this study, we collected data related to avalanche, snowpack, and meteorology during four snow seasons (from 2015 to 2019), and analysed the characteristics and hazards of different types of avalanches. The snow climate of the mid-altitude region of the Central Tianshan Mountains was examined using a snow climate classification scheme, and the results showed that the mountain range has a continental snow climate. To quantify the hazards of different types of avalanches and describe their situation over time in the continental snow climate region, this study used the avalanche hazard degree to assess the hazards of four types of avalanches, i.e., full-depth dry snow avalanches, full-depth wet snow avalanches, surface-layer dry snow avalanches, and surface-layer wet snow avalanches. The results indicated that surface-layer dry snow avalanches were characterized by large sizes and high release frequencies, which made them having the highest avalanche hazard degree in the Central Tianshan Mountains with a continental snow climate. The overall avalanche hazard showed a single peak pattern over time during the snow season, and the greatest hazard occurred in the second half of February when the snowpack was deep and the temperature increased. This study can help the disaster and emergency management departments rationally arrange avalanche relief resources and develop avalanche prevention strategies.
分类： 心理学 >> 心理学其他学科 提交时间： 2021-04-30
摘要： 审美对象特有的刺激属性会唤起观赏者特定的情绪或情感反应。个体在欣赏自然、艺术品和其他人类作品时会产生审美愉悦体验。审美愉悦-兴趣模型（PIA）认为，审美愉悦体验包含审美过程中自动化加工阶段的审美愉悦和控制加工阶段的审美兴趣。近年来，神经美学研究表明，负责愉悦和奖赏的眶额叶皮层在审美过程中广泛激活,是自动化加工阶段初级审美愉悦奖赏的神经基础，而审美过程中纹状体亚回路中不同的连接和功能作用与两个阶段中审美愉悦的产生都有关联；上述结果支持了审美愉悦-兴趣模型。但审美高峰体验时默认模式网络（DMN）相关脑区的激活和负责控制与理性思维的外侧前额叶皮层等脑区的失活，提示在PIA模型强调的自动化加工审美愉悦和控制加工阶段审美兴趣之上，还有整合升华阶段的审美沉浸愉悦，PIA模型需得到进一步的扩展。未来研究应进一步检验审美愉悦认知加工模型及神经机制，探索审美对创造力的影响机制和神经基础，探讨不同审美经验愉悦机制的异同。
分类： 心理学 >> 心理统计 提交时间： 2021-04-30
摘要： 追踪研究当中，交叉滞后模型可以探究多变量之间往复式影响，潜增长模型可以探究个体增长趋势。对两类模型进行整合，例如同时关注往复式影响与个体增长趋势，同时可以定义测量误差、随机截距等变异成分，衍生出随机截距交叉滞后模型、特质-状态-误差模型、自回归潜增长模型、结构化残差潜增长模型等。以交叉滞后模型和潜增长模型分别作为基础模型，从个体间/个体内变异分解的角度对上述各类模型梳理，整合出此类模型的分析框架，并拓展建立“因子结构化潜增长模型(factor latent curve model with structured reciprocals)”作为统合框架。通过实证研究(早期儿童的追踪研究-幼儿园版，ECLS-K)，建立21049名儿童的阅读和数学能力的往复式影响与增长趋势。研究发现，分离了稳定特质的模型拟合最优。研究也对模型建模思路和模型选择提供了建议。
分类： 天文学 >> 天文学 提交时间： 2021-04-29 合作期刊: 《天文研究与技术》
摘要： 使用全球导航卫星系统（GNSS）进行电离层总电子密度（TEC）反演时，单站相对于多站观测网是一种灵活简便的方法。基于人工神经网络，本文提出了一种准实时单站电离层TEC反演的方法。在这种方法中，上一个时段的硬件偏差被作为初值并随着观测值调整，同时电离层TEC也被准实时地反演。为了对这种方法进行详细的评估，通过位于中国的单站，四天磁静日的TEC被分别采用提出的方法与经典的最小二乘球谐函数法反演，其中硬件偏差和TEC的参考值通过附近的多站网得到。在另一个测试中，通过位于欧洲的单站，一次电离层暴事件及前后平静日的TEC也被分别通过上述方法反演。在磁静日，估计的硬件偏差在整体上相对于最小二乘球谐函数法更接近于参考值，反演的TEC也更接近于参考值。电离层暴时，两种方法反演的TEC也具有很好的一致性，神经网络法估计的硬件偏差与磁静日的硬件偏差更接近。结果表明，提出的神经网络法相比最小二乘球谐函数法具有较高的精度。
分类： 天文学 >> 天文学 提交时间： 2021-04-29 合作期刊: 《天文研究与技术》
摘要： 嫦娥四号着陆器搭载的低频射电频谱仪已成功开展观测，每月把观测数据回传到地面，并且把经过一定的预处理后的2C级别的频谱数据释放给了科学团队。本文旨在评估该级别数据是否满足探测宇宙黑暗时代21cm整体谱的要求。我们对生成的2C级别数据进行了长时间积分，并对银河系前景射电辐射被着陆器接收进行了模拟仿真。通过对两套数据进行比对分析，发现2C 数据被减弱40-50 dB，几乎不包含银河系前景的远场辐射信号，这种大幅度的减弱进而影响到了该载荷对宇宙黑暗时代的探测能力。
分类： 天文学 >> 天文学 提交时间： 2021-04-29 合作期刊: 《天文研究与技术》
摘要： 磨损和扭转造成天线俯仰轴结构小尺度变形的快速高精度测量，对修正大口径全可动射电望远镜天线指向精度以及俯仰轴主动健康监测有非常重要的价值。本文提出一种基于虚拟相机的俯仰轴形变测量方法，通过构建单相机测量系统进行数据采集，并建立测量系统数学模型，借助虚拟相机将结构变形转换为虚拟相机空间变换。实验结果表明，该方法在平移分量综合精度可达0.2825mm，旋转分量精度最低可达0.2918o，能够实现俯仰轴1mm尺度变形的快速测量。该系统及其方法具有非接触、精度高、快速性等优点，能满足大口径高频段高精度的射电望远镜俯仰轴长期快速测量需求，也适用于其他大结构小变形测量。
分类： 天文学 >> 天文学 提交时间： 2021-04-29 合作期刊: 《天文研究与技术》
摘要： 为了快速获取副反射面随天线俯仰角变化的位置，并通过调整机构对副面位置进行修正来提高天线综合性能，提出一种虚拟双目视觉测量方法，通过高速相机与平面镜组成的虚拟双目视觉系统对天线观测时副面位置进行模拟实验，获取被测物随实验平台空间移动产生的位置变化图像，并对图像进行预处理、去噪、边缘检测、特征点提取等操作，重建了被测物随实验平台移动而在三维方向上的运动情况，重建结果在三个方向上误差均小于1%，表明该方法具有较高的测量精度，能够较好的对副面位置情况进行重构。
分类： 天文学 >> 天文学 提交时间： 2021-04-29 合作期刊: 《天文研究与技术》
摘要： 日冕抛射物质(Coronal Mass Ejection, CME)是一种强烈的太阳爆发现象，对空间天气和人类生活都有着巨大的影响，因此CME检测对预报CME、保障人类的生产生活安全有重要意义。现有检测方法多采用人为定义特征和人为界定阈值等方法检测CME。由于人为定义特征不能很好表征CME且具有普适性的阈值难于选择，现有CME检测方法对CME的检测效果有待提升。本文提出一种基于Faster R-CNN的日冕抛射物质检测算法。该方法首先结合CDAW、SEEDS、CACTus三个著名CME目录信息，人工标注了包含9113幅日冕图像的数据集，然后根据CME的图像特征较自然图像少、目标尺寸与自然图像有差异等特点，在特征提取和锚点选择方面对Faster R-CNN进行了改进。以2007年6月的CME标注数据为测试集，本文算法检测出了22个强CME事件中的22个和151个弱CME事件中的138个,且对CME事件的中心角和角宽度等特征参数的检测误差分别在5度和10度以内。
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2021-04-29 合作期刊: 《广西植物》
摘要： 走马胎为西南地区常用中药材，被广泛用于食物蒸炖、药浴等日常保健。近年来走马胎叶片被开发成代泡茶，有效拓宽了应用途径。为了明确走马胎叶片营养价值，我们采用国标方法分别对不同栽培年限走马胎叶片的矿质元素、一般营养、氨基酸及活性成分进行了分析和评价，为其开发利用提供科学依据。结果表明：（1）走马胎叶片含有非常丰富的矿质营养，并符合高钾低钠型保健食品特征。1 年生植株叶片矿质元素含量最高，其中磷（P）、钾（K）、铜（Cu）、铁（Fe）、锰（Mn）、锌（Zn）显著高于 2～4 年生植株（P＜0.05）。（2）走马胎叶片的一般营养和氨基酸含量较高，且随栽培年限不同存在明显差异；4 年生植株叶片维生素 C、总糖、氨基酸含量显著高于 1～3 年（P＜0.05）。（3）走马胎叶片含有丰富的酚类和皂苷类物质，黄酮类物质含量较低,其中 1 年生总皂苷和 4 年生总酚含量显著高于其它栽培年限（P＜0.05）。通过与常用果蔬及茶叶对比，走马胎叶片营养价值较高，其中 1 年生矿质营养和皂苷类物质含量最丰富，4 年生一般营养、氨基酸及酚类物质含量最丰富，具有较好的开发利用前景。
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2021-04-29 合作期刊: 《广西植物》
摘要： 互花米草被引入我国滨海地区后，经过多年的生长与演替，改变了潮间带原有生态系统的碳储量，但影响机制仍有待深入研究。为进一步探讨互花米草入侵后潮滩有机碳储量演变特征，本研究以广西北部湾大风江口入侵约 6 a 的互花米草湿地为研究对象，分析了2018 年 8 月、11 月及 2019 年 1 月、3 月采集的样品中有机碳及相关理化指标。结果显示，互花米草植物年均地上碳储量为 9.68 t·hm-2，高于地下根系的 5.56 t·hm-2；互花米草入侵湿地土壤碳储量显著高于互花米草植物本身，且不同季节中春季土壤碳储量显著高于其他季节；土壤的 C/N 比值范围为 3.53 ~ 9.67，表明互花米草入侵群落有机碳受海源的潮汐输入影响较大；互花米草生态系统总碳储量与土壤碳储量之间呈极显著正相关关系，且季节性变化规律一致；随着入侵时间的延长，互花米草生态系统中有机碳储量呈逐渐增加的趋势，表明互花米草入侵提高了光滩的有机碳储量，并能提高光滩的固碳能力。该文可为科学评价互花米草入侵对光滩碳储量的影响提供参考。
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2021-04-29 合作期刊: 《广西植物》
摘要： 描述了自四川西部发现的毛茛科毛茛属五新种，其中三新种，石棉毛茛、细叉叶毛茛和细裂叶毛茛隶属美丽毛茛组，泸定毛茛隶属毛茛组，第五种，丝茎毛茛（特征为植株平卧，匍匐茎十或十多条辐射状开展，花的花瓣 3 片，雄蕊 2 枚）代表一新组。此外还描述了云生毛茛一新变种。
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2021-04-29 合作期刊: 《广西植物》
摘要： 桉树人工林对生态环境的影响一直是全球性争议的热点问题，桉树与珍贵乡土树种混交的生态环境效应备受关注。为探究桉树混交营林措施对林地土壤养分及林下植物功能群的影响，该研究以桉树纯林(PE)、桉树×红锥混交林(MEC)和红锥纯林(PCH)为对象，开展了林下植物群落及环境因子的调查测定。研究结果揭示，不同林分的土壤理化性质具有显著 差异，混交林的土壤 pH、有效氮(AN)和速效磷(AP)含量显著高于纯林；而土壤含水量(SMC)、有机碳(SOC)、总氮(TN)含量及 C:N 和 C:P 在混交林中没有显著优势，并呈现 PEMEC>PCH 的趋势。混交林显著增加林下木本植物功能群(WFG)的物种丰富度，而 PCH 显著增加蕨类植物功能群(FeFG)的物种丰富度。混交林的 WFG 和禾草植物功能群(GFG)的重要值均显著高于红锥纯林，而红锥纯林FeFG 的重要值显著高于混交林。主坐标分析结果表明，混交林与桉树纯林的林下植物功能群组成差异不显著，但与红锥纯林的差异显著；冗余分析结果揭示了 AN 和 AP 是 WFG 占优势的主要影响因子，SMC、TN 和 SOC 是 FeFG 占优势的主要影响因子，SBD 是 GFG 占优势的主要影响因子。研究结果表明，在南亚热带地区桉树与红锥混交在一定程度上能够提高林地土壤养分的有效性和林下植物多样性。
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2021-04-29 合作期刊: 《广西植物》
摘要： 黄酮碳苷，作为战骨植物中的有效成分之一，具有抗骨关节炎的功效。本实验旨在优选植物战骨茎中总黄酮碳苷的富集纯化工艺。以战骨中 5 个黄酮碳苷为考察指标，通过对13 种大孔树脂的静态吸附与解吸实验，优选出合适的大孔树脂，利用高效液相色谱图对结果进行检测，然后利用正交工艺优化富集纯化条件。结果表明 XAD-16N 型大孔树脂对植物战骨茎中黄酮碳苷具有较好的吸附和解吸效果，通过单因素筛选及正交工艺优化，最终确定 其最佳富集纯化工艺为：上样浓度为原提取液稀释 0.5 倍、上样流速 2 BV·h-1、洗脱液浓度60 %乙醇。总黄酮碳苷的含量由 1.73 %（原植物中含量）提高到 14.50 %，提高 7.38 倍。说明优选的提取工艺稳定可行，筛选的大孔树脂富集纯化效果良好，为植物战骨茎的药物开发提供数据参考。
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2021-04-29 合作期刊: 《广西植物》
摘要： 为研究我国特有植物钩毛茜草（Rubia oncotricha）的化学成分，将钩毛茜草70 %乙 醇提取物采用硅胶、ODS、凝胶柱色谱等进行分离纯化，并对所得化合物进行结构鉴定。从 钩毛茜草中共分离了15 个蒽醌类化合物， 分别是 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-α-rhamnosyl(1→2)-β-glucoside (1) 、2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-α-rhamnosyl(1→2)-β-glucoside (2) 、 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(3'-O-acetyl)-α-rhamnosyl(1→2)-β-glucoside (3) 、2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-β-glucoside (4) 、 1,3,6-trihydroxy-2-hydroxymethyl-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-glucopyranoside (5)、2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-glucopyranoside (6)、 大黄素甲醚-8-O-β-D- 葡萄糖苷(7) 、大黄素-8-O-β-D- 葡萄糖苷(8) 、 digiferruginol-11-O-β-gentiobioside (9) 、 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-xylopyranosyl-(1→2)-β-Dglucopyranoside (10) 、6-hydroxyrubiadin (11) 、1,2- 二羟基蒽醌(12) 、大黄酚(13) 、 6-hydroxyxanthopurpurin (14)、1,3-二羟基蒽醌(15)。化合物7、8、14为首次从茜草属植物中 分离得到，化合物1~6、9、10、12、13为首次从该药材中分离得到。
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