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Should Parents Be Held Criminally Liable for Health and Safety Failures Harming Their Children?
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《ChinAfrica》 2017年第5期12-13,共2页
A proposal appealing for harsher punishment legislation for negligent parents and guardians has provoked a long and heated online debate in China. During the 2017 Sessions of the National People's Congress and the N... A proposal appealing for harsher punishment legislation for negligent parents and guardians has provoked a long and heated online debate in China. During the 2017 Sessions of the National People's Congress and the National Committee of the Chinese People's Political Consultative Conference (CPPCC), Li You and 12 other members of the CPPCC National Committee proposed that parents and guardians who cause bodily harm or death to a child as a result of negligence should be punished by the Criminal Law. 展开更多
关键词 Should Parents Be Held Criminally Liable for Health and Safety Failures harming Their Children BE
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The abundance,distribution,and enrichment mechanism of harmful trace elements in coals from Guizhou,Southwestern China 被引量:1
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作者 Hui Hou Wei Cheng +1 位作者 Ruidong Yang Yan Zhang 《Acta Geochimica》 EI CAS CSCD 2024年第5期889-903,共15页
Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of eac... Coal seams can enrich a variety of harmful trace elements under specific geological conditions.The spatial distribution of harmful trace elements in coal is extremely uneven,and the distribution characteristics of each element content are different.The harmful elements released in the process of coal mining and utilization will cause serious harm to the environment and the human body.It is of great resource significance to study the geochemistry of coal that affects the enrichment and distribution characteristics of harmful trace elements.Based on the domestic and foreign literature on coal geochemistry in Guizhou published by previous investigators,this study counted 1097 sample data from 23 major coal-producing counties in Guizhou Province,systematically summarized the relevant research results of harmful trace elements in the coal of Guizhou,and revealed the overall distribution and enrichment characteristics of harmful trace elements in the coal of Guizhou.The results show that the average contents of Cd,Pb,Se,Cu,Mo,U,V,As,Hg,and Cr in coal of Guizhou are higher than those in Chinese coal and world coal.A variety of harmful trace elements in the coal of Guizhou have high background values,especially in Liupanshui,Xingyi and Qianbei coalfield.The enrichment of various harmful trace elements in the Late Permian coal in Guizhou is mainly related to the combined action of various geological and geochemical factors.The supply of terrigenous debris and sedimentary environment may be the basic background of the enrichment of harmful elements in western Guizhou,while low-temperature hydrothermal activity and volcanic ash deposition may be the main reasons for the enrichment of harmful elements in southwestern Guizhou. 展开更多
关键词 Harmful trace elements Distribution characteristics Enrichment law Geological and geochemical features GUIZHOU
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An Improved YOLOv8-Based Method for Real-Time Detection of Harmful Tea Leaves in Complex Backgrounds
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作者 Xin Leng Jiakai Chen +2 位作者 Jianping Huang Lei Zhang Zongxuan Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第11期2963-2981,共19页
Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and qu... Tea,a globally cultivated crop renowned for its uniqueflavor profile and health-promoting properties,ranks among the most favored functional beverages worldwide.However,diseases severely jeopardize the production and quality of tea leaves,leading to significant economic losses.While early and accurate identification coupled with the removal of infected leaves can mitigate widespread infection,manual leaves removal remains time-con-suming and expensive.Utilizing robots for pruning can significantly enhance efficiency and reduce costs.How-ever,the accuracy of object detection directly impacts the overall efficiency of pruning robots.In complex tea plantation environments,complex image backgrounds,the overlapping and occlusion of leaves,as well as small and densely harmful leaves can all introduce interference factors.Existing algorithms perform poorly in detecting small and densely packed targets.To address these challenges,this paper collected a dataset of 1108 images of harmful tea leaves and proposed the YOLO-DBD model.The model excels in efficiently identifying harmful tea leaves with various poses in complex backgrounds,providing crucial guidance for the posture and obstacle avoidance of a robotic arm during the pruning process.The improvements proposed in this study encompass the Cross Stage Partial with Deformable Convolutional Networks v2(C2f-DCN)module,Bi-Level Routing Atten-tion(BRA),Dynamic Head(DyHead),and Focal Complete Intersection over Union(Focal-CIoU)Loss function,enhancing the model’s feature extraction,computation allocation,and perception capabilities.Compared to the baseline model YOLOv8s,mean Average Precision at IoU 0.5(mAP0.5)increased by 6%,and Floating Point Operations Per second(FLOPs)decreased by 3.3 G. 展开更多
关键词 Harmful tea leaves YOLO-DBD Focal-CIoU Loss dynamic head Bi-Level Routing Attention
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Determination of Total Flavonoids in Acanthopanax senticosus(Rupr. et Maxim.) Harms by Enzymolysis and Its Technological Optimization
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作者 Li Xinzhi Wang Yudan +4 位作者 Wang Meiliang Liu Tianyang Gao Ruihua Qiu Youwen Zhang Shunjie 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期53-60,共8页
In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively... In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively analyzed. The ultrasonic extraction technology was optimized by Box-Behnken response surface method, and the total flavonoid content of 21 kinds of Acanthopanax senticosus(Rupr. et Maxim.) Harms from different producing areas were analyzed by cluster analysis. The optimal process conditions were determined as ultrasonic time 30 min, solid-liquid ratio 1 : 12 and ultrasonic power 250 W, and the average yield of the total flavonoid was 1.453 mg·g^ (-1). By optimizing the ultrasonic-assisted extraction method, the total flavonoid content from different producing areas was compared in the experiment, which provided certain data support for the optimization of the extraction process in the future and laid a certain theoretical foundation for the quality analysis of Chinese medicinal materials. 展开更多
关键词 Acanthopanax senticosus(Rupr.et Maxim.)Harms total flavonoid Box-Behnken response surface test ultrasonic-assisted extraction
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Harm of Hail to Crops and Countermeasures of Artificial Hail Suppression in Ulanqab City
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作者 Pei WANG Tengge'er WU Jinhua LIU 《Meteorological and Environmental Research》 2024年第2期62-63,70,共3页
Hail is one of meteorological disasters affecting crop growth in Ulanqab City.It happens frequently from May to September,and this period is also the main growing season of crops.In this period,hail will cause damage ... Hail is one of meteorological disasters affecting crop growth in Ulanqab City.It happens frequently from May to September,and this period is also the main growing season of crops.In this period,hail will cause damage to crops,make farmland soil harden,and bring varying degrees of harm to agricultural production.Artificial hail suppression is an important scientific and technological means for disaster prevention and mitigation.It is necessary to strengthen the monitoring,analysis and forecast of severe convection weather,intensify the release of early warning information of hail weather,provide accurate and reliable real-time information for the implementation of artificial hail suppression operations,strengthen the implementation of artificial weather modification,effectively carry out artificial hail suppression operations,and avoid and reduce the impact of hail disaster. 展开更多
关键词 HAIL CROPS HARM Artificial hail suppression Ulanqab City
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Changes of Water Temperature and Harmful Algal Bloom in the Daya Bay in the Northern South China Sea 被引量:7
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作者 余景 唐丹玲 +2 位作者 王素芬 练建生 王友绍 《Marine Science Bulletin》 CAS 2007年第2期25-33,共9页
Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station (DNPS) in 1994. This... Economic development around the Daya Bay, China has profoundly affected the marine environment in the bay area in recent years, particularly since the operation of Daya Bay Nuclear Power Station (DNPS) in 1994. This study analyzed the changes of water temperature and harmful algal blooms (HABs) for two periods: 1983-1993 and 1994-2004, using in situ and satellite data. Results showed that yearly mean surface water temperature (SWT) and Chl-a concentration (Chl-a) increased by 1.1 ℃ and 1.9 mg/m^3, respectively, after 1994. The monthly occurrence of HAB was found to have increased also. HABs appeared only in spring and autumn before 1994, but occurred all the year round after 1994. SWT, Chl-a and HABs all increased significantly in May. Those changes were associated with environmental changes in this area, such as thermal discharge from the DNPS and enhancement of eutrophication from human activities around the Daya Bay. 展开更多
关键词 water temperature Harmful Algal Bloom Chlorophyll a nuclear power station Daya Bay China
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东海原甲藻(Prorocentrum donghaiense)和链状亚历山大藻(Alexandrium catenella)对模拟食物链物质传递的影响 被引量:7
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作者 陈洋 颜天 周名江 《生态学报》 CAS CSCD 北大核心 2007年第10期3964-3972,共9页
研究了东海原甲藻的基本营养组成,并就赤潮密度下的东海原甲藻(Prorocentrum donghaiense)和链状亚历山大藻(Alexandrium catenella)在单一和混合情况下对赤潮藻→卤虫模拟食物链物质传递的影响进行了探讨。结果表明:与其它饵料微藻相比... 研究了东海原甲藻的基本营养组成,并就赤潮密度下的东海原甲藻(Prorocentrum donghaiense)和链状亚历山大藻(Alexandrium catenella)在单一和混合情况下对赤潮藻→卤虫模拟食物链物质传递的影响进行了探讨。结果表明:与其它饵料微藻相比,东海原甲藻必需氨基酸中的苯丙氨酸、赖氨酸和组氨酸含量明显偏低。东海原甲藻单独投喂时,卤虫对其的总物质转化效率随着藻密度的增加呈现先逐渐增加再逐渐降低的趋势。而当不同密度的东海原甲藻分别与一种硅藻小新月菱形藻(Nitzschia closterium)混合投喂时,随东海原甲藻密度的增加,卤虫选择性地增加对东海原甲藻的摄食,而降低对小新月菱形藻的摄食,并且其总物质转化效率逐渐降低。暴露于链状亚历山大藻藻液,卤虫体重减轻,且在其体内未检测到叶绿素a,表明卤虫未摄食该藻。当链状亚历山大藻藻细胞重悬液和去藻过滤液分别与小新月菱形藻或东海原甲藻混合时,卤虫对后两株藻的摄食量和总物质转化效率均有所降低。因此,在大规模赤潮发生时,东海原甲藻和链状亚历山大藻可能分别对浮游动物的营养和存活带来不利影响,并影响物质沿食物链的传递。 展开更多
关键词 有害赤潮(Harmful ALGAL BLOOMS HABs) 东海原甲藻 链状亚历山大藻 卤虫 总物质转化效率 营养组成
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热泵型空调系统制冷剂流量控制方法的研究 被引量:8
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作者 苏顺玉 张春枝 陈俭 《暖通空调》 北大核心 2009年第3期128-130,共3页
以Harms模型计算两相区内的空泡系数,用稳态分布参数法计算了制冷和制热两种运行工况下热泵型空调系统冷凝器和蒸发器内所含的制冷剂量。结果表明,制热工况下的制冷剂充注量比制冷工况下的充注量小。在此基础上提出了储液器法和喷射液... 以Harms模型计算两相区内的空泡系数,用稳态分布参数法计算了制冷和制热两种运行工况下热泵型空调系统冷凝器和蒸发器内所含的制冷剂量。结果表明,制热工况下的制冷剂充注量比制冷工况下的充注量小。在此基础上提出了储液器法和喷射液态制冷剂法两种制冷剂流量控制方法。 展开更多
关键词 Harms模型 制冷剂充注量 储液器 喷射
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红毛五加叶水提液对羟自由基清除率的测定 被引量:6
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作者 杨鑫嵎 杨文宇 叶强 《安徽农业科学》 CAS 北大核心 2011年第35期21653-21656,21659,共5页
[目的]测定红毛五加叶水提液对羟自由基的清除率并评价其抗氧化活性。[方法]利用Fenton反应产生羟自由基,用二甲亚砜(DMSO)捕获羟自由基并与之反应生成甲醛,甲醛经2,4-二硝基苯肼衍生成相应的苯腙,通过HPLC检测加或不加样品时该苯腙的... [目的]测定红毛五加叶水提液对羟自由基的清除率并评价其抗氧化活性。[方法]利用Fenton反应产生羟自由基,用二甲亚砜(DMSO)捕获羟自由基并与之反应生成甲醛,甲醛经2,4-二硝基苯肼衍生成相应的苯腙,通过HPLC检测加或不加样品时该苯腙的峰面积的变化,从而计算红毛五加叶水提液对羟自由基的清除率。色谱条件:色谱柱为Diamonsil C18(250 mm×4.6 mm5,μm),流动相为乙腈-水(65∶35,V/V),流速为0.8 ml/min,检测波长为365 nm。[结果]Fenton反应体系为2.0 mmol/L Fe2++107.7 mmol/L H2O2+225.2 mmol/L DMSO;在该反应体系中红毛五加叶水提液清除羟自由基的IC50为0.67 mg/ml(即每1 ml含药材量为0.67 mg);红毛五加叶总皂苷是清除羟自由基的活性成分。[结论]红毛五加叶水提液能够清除Fenton反应产生的羟自由基,具有较强的抗氧化活性。 展开更多
关键词 红毛五加(Acanthopanax giraldii Harms.) FENTON反应 HPLC 抗氧化
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不同处理对红毛五加嫩枝扦插生根的影响 被引量:3
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作者 李强峰 彭政 +3 位作者 明家琪 刘毅 赵盼盼 隆雨薇 《安徽农业科学》 CAS 北大核心 2011年第26期15924-15926,共3页
[目的]研究不同处理对红毛五加嫩枝扦插生根的影响。[方法]采用L9(34)正交试验设计,研究基质、扦插时期、插穗部位和激素浓度对红毛五加嫩枝插穗生根的影响。[结果]基质、扦插时期、插穗部位和激素浓度对红毛五加嫩枝插穗生根状况的影... [目的]研究不同处理对红毛五加嫩枝扦插生根的影响。[方法]采用L9(34)正交试验设计,研究基质、扦插时期、插穗部位和激素浓度对红毛五加嫩枝插穗生根的影响。[结果]基质、扦插时期、插穗部位和激素浓度对红毛五加嫩枝插穗生根状况的影响均达显著水平;各因素对成活率影响的主次顺序为扦插时期>基质>激素浓度>插穗部位,对根长影响的主次顺序为插穗部位>激素浓度>基质>扦插时期,对根数影响的主次顺序为插穗部位>基质>激素浓度>扦插时期;以选择带叶片的中部或下部插穗,以100%蛭石为基质,在6月25日,用100 mg/L ABT1处理2 h,进行扦插育苗效果最好,生根率为86.4%,插穗的平均根长为6.2 cm,平均根数为4.9条。[结论]采用红毛五加嫩枝为材料进行大规模温室容器扦插育苗是完全可行的。 展开更多
关键词 红毛五加(Acanthopanax giraldii Harms) 嫩枝扦插 生根率 根长 根数
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Advance in Rice Bacterial Leaf Streak Researches 被引量:4
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作者 张荣胜 陈志谊 刘永锋 《Agricultural Science & Technology》 CAS 2015年第2期298-305,310,共9页
Rice bacterial leaf streak,caused by Xanthomonas oryzae pv.oryzicola,is an important bacterial disease in rice-planting areas in South China and Southeast Asian countries.It occurs every year in local areas.This paper... Rice bacterial leaf streak,caused by Xanthomonas oryzae pv.oryzicola,is an important bacterial disease in rice-planting areas in South China and Southeast Asian countries.It occurs every year in local areas.This paper reviews the research advance in the occurrence and harms of rice bacterial leaf streak in China,classification of Xanthomonas oryzae and infection characteristics,pathogenic factors and pathogenicity of rice bacterial leaf streak and breeding of bacterial leaf streakresistance rice cultivars.Some issues involved in occurrence and control of rice bacterial leaf streak were presented,and the areas on which the future studies might be focused were discussed. 展开更多
关键词 Rice bacterial leaf steak Xanthomonas oryzae Occurrence and harm Control
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刺五加中皂苷类化合物的UPLC-ESI MS研究 被引量:2
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作者 杜振霞 赵开径 《分析测试学报》 CAS CSCD 北大核心 2008年第S1期80-82,共3页
A ultra performance liquid chromatography-electrospray ionization mass spectrometry(UPLC-ESI MS)method was developed for the analysis of saponins in crude extracts from Acanthopanax senticosus Harms.The analysis was p... A ultra performance liquid chromatography-electrospray ionization mass spectrometry(UPLC-ESI MS)method was developed for the analysis of saponins in crude extracts from Acanthopanax senticosus Harms.The analysis was performed on a reversed-phase C18 column using a binary eluent(methanol and 0.2% aqueous HCOOH) under gradient conditions.Three major peaks were detected in the negative ion mode.The molecular -ions of saponins were observed,and the relative molecular mass were obtained.The structure of the ginsenosides was identified by a collision induced dissociation(CID) experiment.The UPLC-ESI MS method was particularly useful in the identification of some saponins. 展开更多
关键词 ACANTHOPANAX senticosus HARMS SAPONINS UPLC-ESI MS
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Fluorescence-assisted Image Analysis of Harmful Microalgae 被引量:1
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作者 王学民 孙勇 曹红宝 《Marine Science Bulletin》 CAS 2006年第1期75-82,共8页
In order to realize the detection and analysis of microalgae in sediment samples with complex scenes, the project takes advantage of the character of microalgae that they can auto-fluoresce when exposed to the illumin... In order to realize the detection and analysis of microalgae in sediment samples with complex scenes, the project takes advantage of the character of microalgae that they can auto-fluoresce when exposed to the illumination of certain exciation waves. The project takes grey-scale and fluorescent pictures of microalgae in the same field of view and uses the image processing technique to deal with the images, such as threshold segmentation, contour and texture analysis and pattern recognition. The results show that the fluorescent image can effectively elimate the yawp in the complex background and make the consequent image processing more effective and easy. Then the project comes to the conclusion that fluorescence-assisted image processing can realize the detection and analysis of microalgae in sediment samples containing complex scenes. 展开更多
关键词 harmful microalgae image segmentation FLUORESCENCE
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不同营养液浓度对鹅掌柴生长的影响 被引量:5
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作者 李秋杰 张竹南 《长江大学学报(自然科学版)》 CAS 2017年第18期18-21,共4页
采用Hoagland&Arnon的原溶液、1/2剂量、1/4剂量3种浓度的营养液和清水(对照)培养鹅掌柴(Schefflera octophylla(Lour.)Harms)小植株后,对地上部与地下部的生长情况进行了比较。结果表明:对鹅掌柴植株枝叶生长的影响中,除侧枝粗度... 采用Hoagland&Arnon的原溶液、1/2剂量、1/4剂量3种浓度的营养液和清水(对照)培养鹅掌柴(Schefflera octophylla(Lour.)Harms)小植株后,对地上部与地下部的生长情况进行了比较。结果表明:对鹅掌柴植株枝叶生长的影响中,除侧枝粗度无明显增加外,Hoagland&Arnon原溶液、1/2剂量处理的新生叶抽生速度和侧枝长度增长明显优于Hoagland&Arnon 1/4剂量和对照;Hoagland&Arnon原溶液、1/2剂量处理的鹅掌柴的一级根和活力根的数量明显多于对照,但Hoagland&Arnon原溶液处理的根长短于Hoagland&Arnon 1/2剂量。因此,综合来看,以Hoagland&Arnon 1/2剂量处理的效果最好。 展开更多
关键词 鹅掌柴(Schefflera octophylla(Lour.)Harms) 营养液 水培
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家用空调换热器内充注量的研究 被引量:7
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作者 苏顺玉 张春枝 陈俭 《建筑热能通风空调》 2008年第5期39-41,共3页
对冷凝器和蒸发器内所含制冷剂量的计算是空调系统充注量计算的关键,而冷凝器和蒸发器内的制冷工质又主要以气液两相状态存在,因此两相区内的制冷剂质量的计算需要选择合适的空泡系数模型。本文以Harms模型计算两相区内的空泡系数,并在H... 对冷凝器和蒸发器内所含制冷剂量的计算是空调系统充注量计算的关键,而冷凝器和蒸发器内的制冷工质又主要以气液两相状态存在,因此两相区内的制冷剂质量的计算需要选择合适的空泡系数模型。本文以Harms模型计算两相区内的空泡系数,并在Harms模型的基础上对冷凝器和蒸发器内所含制冷剂量进行了计算和分析。结果表明,家用空调系统内的充注量主要分布在冷凝器和蒸发器内。 展开更多
关键词 空调换热器 Harms模型 空泡系数 充注量
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“爱国者”雷达被F-16攻击初步分析 被引量:3
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作者 方有培 《航天电子对抗》 2003年第6期1-4,共4页
20 0 3年 3月 ,伊拉克战争的第四天 ,美军一架F 1 6战斗机向自己的一个“爱国者”导弹营发射了高速反辐射导弹 (HARM ) ,击毁了导弹阵地的相控阵雷达 ,这种“大水冲了龙王庙 ,一家人不认一家人”的事件 ,已多次发生。对该“误击”
关键词 相控阵雷达 敌我识别器 “爱国者”导弹 HARM导弹 F-16战斗机 反辐射导弹 机载装备
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Backwash Effects of Language Testing in EFL Classrooms
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作者 赵秦岭 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期100-105,共6页
The article presents some major researches concerning the concept of backwash effect of language testing; analyses both the positive and negative effects and their implications in EFL classrooms; then provides some su... The article presents some major researches concerning the concept of backwash effect of language testing; analyses both the positive and negative effects and their implications in EFL classrooms; then provides some suggested ways to be followed when creating positive backwash effects on teaching and learning. 展开更多
关键词 BACKWASH EFFECT positive/beneficial negative/harmful EFL CLASSROOMS
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Investigation on the Harm of Wild Boar in Mingtong Town, Chengkou, Chongqing
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作者 王正春 张后伟 吴旭 《Agricultural Science & Technology》 CAS 2017年第12期2446-2449,共4页
Through the investigation and analysis of the wild boars in Mingtong Town, Chengkou, Chongqing, it was concluded that the area had long been seri- ously affected by wild boars and some of the human activities were pot... Through the investigation and analysis of the wild boars in Mingtong Town, Chengkou, Chongqing, it was concluded that the area had long been seri- ously affected by wild boars and some of the human activities were potentially threatened, and the potential threat areas were identified. Corresponding suggestions were proposed to guide the prevention and control work, so as to protect the habi- tat and reproduction of wildlife and ensure the normal production and life of the masses. 展开更多
关键词 Wild boar HARM THREAT Prevention and control
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Pigment characterization for the 2011 bloom in Qinhuangdao implicated "brown tide" events in China 被引量:19
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作者 孔凡洲 于仁成 +2 位作者 张清春 颜天 周名江 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第3期361-370,共10页
A large-scale bloom occurred from May to June in 2011 in sea area near Qinhuangdao of the Bohai Sea, leading to huge damage of the scallop culture industry. Similar blooms have been observed in this region for three y... A large-scale bloom occurred from May to June in 2011 in sea area near Qinhuangdao of the Bohai Sea, leading to huge damage of the scallop culture industry. Similar blooms have been observed in this region for three years. The causative species of the bloom, which dominated the phytoplankton community with the maximum cell density around 109 cell/L, could not be identified with morphological features due to the small cell size (-2 μm). A pigment analytical method was then adopted to analyze the pigment profile of the phytoplankton samples collected from the blooming sea area. It was found that pico-sized (〈2 μm), nano-sized (2-20 μm), and bulk phytoplankton samples had similar pigment profile, representing the pigment signature of the bloom-causative species. The major pigments detected included 19-butanoyloxyfucoxanthin (But-fuco), fucoxanthin (Fuco), diadinoxanthin (Diad) and chlorophyll a (Chl a), and high content of But-fuco was the most significant characteristics of the phytoplankton samples. Based on the pigment composition and content, the bloom-causative species could be tentatively identified as pelagophyte, "type 8" group of haptophyte, or silicoflagellate. Some unique features of the bloom, such as the extremely high cell density, small-sized and But-fuco containing cells, occurring in early summer, and the feeding-cessation effects on scallops, suggest it be a "brown tide" event similar to those reported in the east coast of the United States of America. The recurrent "brown tide" events and their dramatic impacts on the shellfish mariculture industry in QirLhuangdao need close attention in the coming years. 展开更多
关键词 harmful algal bloom PIGMENT HPLC 19-butanoyloxyfucoxanthin pelagophyte haptophyte
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Effects of temperature, salinity, and irradiance on the growth of harmful algal bloom species Phaeocystis globosa Scherffel(Prymnesiophyceae) isolated from the South China Sea 被引量:11
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作者 徐宁 黄博珠 +3 位作者 胡章喜 唐赢中 段舜山 张成武 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期557-565,共9页
Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal ... Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal waters that facilitate its rapid expansion, the effects of temperature, salinity and irradiance on the growth of P. globosa from the South China Sea were examined in the laboratory. The saturating irradiance for the growth ofP. globosa (Is) was 60 μmol/(m^2·s), which was lower than those of other harmful algal species (70-114μmol/(m^2·s)). A moderate growth rate of 0.22/d was observed at 2 μmol/(m^2·s) (the minimum irradiance in the experiment), and photo-inhibition did not occur at 230 μmol/(m^2·s) (the maximum irradiance in the experiment). Exposed to 42 different combinations of temperatures (10- 31 ℃) and salinities (10-40) under saturating irradiance, P. globosa exhibited its maximum specific growth rate of 0.80/d at the combinations of 24℃ and 35, and 27℃ and 40. The optimum growth rates (〉0.80/d) were observed at temperatures ranging from 24 to 27℃ and salinities from 35 to 40. While P. globosa was able to grow well at temperatures from 20℃ to 31℃ and salinities from 20 to 40, it could not grow at temperatures lower than 15℃ or salinities lower than 15. Factorial analysis revealed that temperature and salinity has similar influences on the growth of this species. This strain ofP. globosa not only prefers higher temperatures and higher salinity, but also possesses a flexible nutrient competing strategy, adapted to lower irradiance. Therefore, the P. globosa population from South China Sea should belong to a new ecotype. There is also a potentially high risk of blooms developing in this area throughout the year. 展开更多
关键词 Phaeocystis globosa harmful algal bloom TEMPERATURE SALINITY IRRADIANCE GROWTH
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