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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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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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Combustion mechanism and control approaches of underground coal fires:a review 被引量:3
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作者 Yuntao Liang Yalan Yang +2 位作者 Sida Guo Fuchao Tian Shaofeng Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第2期58-82,共25页
With the large-scale mining of coal resources,the huge economic losses and environmental problems caused by underground coal fires have become increasingly prominent,and the research on the status quo and response str... With the large-scale mining of coal resources,the huge economic losses and environmental problems caused by underground coal fires have become increasingly prominent,and the research on the status quo and response strategies of underground coal fires is of great significance to accelerate the green prevention and control of coal fires,energy conservation and emission reduction.In this paper,we summarized and sorted out the research status of underground coal fires,focused on the theoretical and technical issues such as underground coal fire combustion mechanism,multiphysics coupling effect of coal fire combustion,fire prevention and extinguishing technology for underground coal fires,and beneficial utilization technology,and described the latest research progress of the prevention and control for underground coal fire hazards.Finally,the key research problems in the field of underground coal fire hazards prevention and control were proposed in the direction of the basic theory,technology research,comprehensive management and utilization,with a view to providing ideas and solutions for the management of underground coal fires. 展开更多
关键词 Underground coal fire Combustion mechanism Multiphysics coupling effect Disaster prevention and control Turning harm into benefit Response strategy
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Factors inducing morphological transition in harmful algal bloom-forming species Phaeocystis globosa with emphasis on predator chemical cue
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作者 Xiao YANG Pingping SHEN Ke LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1537-1546,共10页
The microalga Phaeocystis globosa is recognized as a harmful alga and also one of the few keystone phytoplankton genera that shape the structure and function of marine ecosystems.P.globosa possess a complex polymorphi... The microalga Phaeocystis globosa is recognized as a harmful alga and also one of the few keystone phytoplankton genera that shape the structure and function of marine ecosystems.P.globosa possess a complex polymorphic life cycle,exhibiting phase alternation between free-living cells of approximately 3-6μm in diameter and gelatinous colonies(palmelloid stage)reaching several millimeters.The knowledge on the factors that induced the morphological transition of P.globosa in the last two decades was reviewed.Emphasis is given to infochemicals,an additional biological factor induced by predator,with the attempt to reveal a relevant mechanism of induced morphological defense. 展开更多
关键词 Phaeocystis globosa POLYMORPHISMS harmful algal blooms defense strategies INFOCHEMICAL
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Comparison of short-term toxicity of 14 common phycotoxins(alone and in combination)to the survival of brine shrimp Artemia salina
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作者 Yuting Zhang Shanshan Song +7 位作者 Bin Zhang Yang Zhang Miao Tian Ziyi Wu Huorong Chen Guangmao Ding Renyan Liu Jingli Mu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期134-141,共8页
Toxic harmful algal blooms(HABs)can cause deleterious effects in marine organisms,threatening the stability of marine ecosystems.It is well known that different strains,natural populations and growth conditions of the... Toxic harmful algal blooms(HABs)can cause deleterious effects in marine organisms,threatening the stability of marine ecosystems.It is well known that different strains,natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity.To fully assess the ecological risk of toxic HABs,it is of great importance to investigate the toxic effects of phycotoxins in marine organisms.In this study,the short-term toxicity of 14 common phycotoxins(alone and in combination)in the marine zooplankton Artemia salina was investigated.The 48 h LC_(50)of the 14 phycotoxins varied from 0.0193µg/mL to 2.415µg/mL.The most potent phycotoxin was azaspiracids-3(AZA3;with a LC_(50)of 0.0193µg/mL),followed by azaspiracids-2(AZA2;0.0226µg/mL),pectenotoxin-2(PTX2;0.0460µg/mL)and dinophysistoxin-1(DTX1;0.0818µg/mL).For the binary exposure,okadaic acid(OA)induced potential additive effects with DTX1,probably due to their similar structure(polyether fatty acid)and mode of action(attacking the serine/threonine phosphoprotein phosphatases).On the other hand,OA showed potential antagonistic effects with PTX2,which might be accounted for by their activation on the detoxification activity of cytochrome P450 activity.In addition,DTX1 induced potential synergetic effects with saxitoxin(STX),yessotoxin(YTX)or PTX2,suggesting the hazard potency of the mixtures of DTX1 and other phycotoxins(like STX,YTX and PTX2)with regard to the ecological risk.These results provide valuable toxicological data for assessing the impact of phycotoxins on marine planktonic species and highlight the potential ecological risk of toxic HABs in marine ecosystems. 展开更多
关键词 LC_(50) harmful algal blooms binary exposure ecological risk
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Artisanal Mining and Soil Quality in the Sudano-Sahelian Climate: Case of the Artisanal Mining Site of Yimiougou in Burkina Faso, West Africa
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作者 Nicolas Kagambega Urbain Sam Mathias Ouedraogo 《Journal of Environmental Protection》 CAS 2023年第1期1-15,共15页
The majority of the population of Burkina Faso lives from agriculture and therefore depends on the land. The main objective of this study is to assess the quality of the soils in the area linked to artisanal mining ac... The majority of the population of Burkina Faso lives from agriculture and therefore depends on the land. The main objective of this study is to assess the quality of the soils in the area linked to artisanal mining activities. The methodology adopted consisted in sampling and characterizing the main types of soil. In order to assess the level of soil pollution by artisanal mining, parameters such as the geo-accumulation index (Igeo) and the contamination factor (CF) are calculated. A prediction of acid mine drainage (AMD) was also carried out on samples of mine tailings which are potential sources of pollution of these soils. The results obtained show that the soils in Yimiougou are of nil to low agronomic interest. The Igeo shows that for lead, copper, zinc and arsenic the levels found in the different morphological units are partly attributable to human action and specifically artisanal mining. The values of the contamination factor indicate contamination. Cobalt presents the lowest contamination. For cadmium, the different types of soil are moderately contaminated except for the FITLC type, which has a CF value of 0.50, therefore synonymous with low or absent contamination. The various morphological units studied are very heavily contaminated with zinc, copper, lead and arsenic. The pH and conductivity values indicate that the mine tailings samples are non-acidogenic, therefore not yet oxidized. As for the sulphide contents, they show that only samples S17, S22, S23 and S24 present values that are strictly above the threshold (0.3%) and therefore potentially acid-generating. The comparative study of the acid potential (AP) and the neutralization potential (NP) reveals that the neutralization potentials of the different samples are clearly higher than the acid potentials even for the samples which present a proven acidification potential (S17, S22, S23 and S24). These results show that the mine tailings have the natural capacity to neutralize any possible mine drainage, given the presence of acid-eating minerals such as the carbonates associated with the mineralization. 展开更多
关键词 Soil Artisanal Mining Environment Heavy Metals Potentially Harmful Elements Burkina Faso
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Electrochemically and Ultrasonically-Enhanced Coagulation for Algae Removal
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作者 Djamel Ghernaout Noureddine Elboughdiri 《Green and Sustainable Chemistry》 CAS 2023年第2期73-109,共37页
At the global level, the augmenting presence of harmful algae blooms constitutes important dares to water treatment plants (WTPs). In WTPs, coagulation remains the primary process of the applied procedure to treat alg... At the global level, the augmenting presence of harmful algae blooms constitutes important dares to water treatment plants (WTPs). In WTPs, coagulation remains the primary process of the applied procedure to treat algae-contaminated water. Such a chemical process influences the following techniques;thus, regulating coagulation parameters to eliminate algae at the maximum degree without provoking cell deterioration is more than crucial. This work aims to review coagulation-founded methods for algae elimination. First, investigations concentrating on algae elimination using the chemical process are discussed. The introduction presents the widespread algae encountered in the water treatment field. Then, habitually utilized experimental techniques and emerging methods in coagulation investigations are summarized with typical findings. Next, the newest expansions in improved algae elimination, launched by electrochemically and ultrasonically-enhanced coagulation, are discussed. Workable thoughts for applying coagulation to eliminate algae in WTPs are also debated. The paper finishes by defining restrictions and dares related to the present literature and suggesting trends for subsequent studies. The charge neutralization mechanism efficiently removes solubilized microcystins (MCs), and enhanced coagulation configuration is also found to be more efficient for their removal. However, considerations should be taken to avert that the acid introduction has no unwanted effect in killing algae treatment to avoid the solubilized MCs level elevation. If such techniques are well-optimized and controlled, both algae and solubilized MCs could be efficaciously removed by ultrasound-enhanced coagulation and electrocoagulation/electrooxidation. 展开更多
关键词 Harmful Algal Blooms (HABs) Electrocoagulation (EC) Electrooxidation (EO) Ultrasound (US) Machine Learning (ML) Reactive Oxygen Species (ROSs)
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The Evaluation of Social Sharing Nets Users’ Fundamental Principals According to Nickname Usage and Time Spent
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作者 Mehmet Ali Seven Mustafa Çağrı Engin +1 位作者 Mehmet Yıldız Ali Osman Engin 《Advances in Internet of Things》 2023年第2期31-62,共32页
This work;It was made to determine the positive and negative usage information, attitudes and behaviors of social networking networks for users. Today, it is well known how the wide social effects of social networking... This work;It was made to determine the positive and negative usage information, attitudes and behaviors of social networking networks for users. Today, it is well known how the wide social effects of social networking sites are widespread and effective. As far as it can be followed from written and visual media, it causes significant damages for attitudes and behaviors for individuals. Looking at the results of the study, it seems impossible to limit the time and necessity of these networks for people, but it is understood that people force their limits and capacity. It was determined that the general acceptance and rejection areas are mixed and the dominant distinctive effects were weakened. Unable to prevent social dissolution and deterioration was realized by these social networks of networks. However, we cannot only talk about negative effects because their positive effects should be mentioned. Data were obtained in this direction. For example, some segments encourage the users of these sites to have more freedom, to develop democracy and human rights awareness. However, the real problem is when and where to stand. This study;Social networking networks use information, attitudes and behaviors;It was carried out for the purpose of evaluating the use of nicknames and networks for the use of networks. The data of the study were obtained by the application of a questionnaire and the data obtained were analyzed with appropriate statistical analysis methods. In the first part of the study, field study/operational concept scanning is performed and theoretical information is included. In the second part, the purpose of the study, the problem status, the importance of the study, limitations, assumptions, problem question, research method, research universe and sample are specified and informed. In the third section, the data obtained using appropriate statistical methods are analyzed. In the last section, some important suggestions and comments are made in the light of the data obtained. 展开更多
关键词 Psycho-Social Effect of Facebook Facebook and Personal Harms Habitual Activity of Using Facebook Nickname Usage and Social Sharing Nets
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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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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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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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Isolation and Characterization of an Algicidal Bacterium Indigenous to Lake Taihu with a Red Pigment able to Lyse Microcystis aeruginosa 被引量:20
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作者 YANG Fei WEI Hai Yan +4 位作者 LI Xiao Qin LI Yun Hui LI Xiao Bo YIN Li Hong PU Yue Pu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第2期148-154,共7页
Objective To isolate and characterize indigenous algicidal bacteria and their algae-lysing compounds active against Microcystis aeruginosa, strains TH1, TH2, and FACHB 905. Methods The bacteria were identified using t... Objective To isolate and characterize indigenous algicidal bacteria and their algae-lysing compounds active against Microcystis aeruginosa, strains TH1, TH2, and FACHB 905. Methods The bacteria were identified using the Biolog automated microbial identification system and 16S rDNA sequence analysis. The algae-lysing compounds were isolated and purified by silica gel column chromatography and reverse-phase high performance liquid chromatography. Their structures were confirmed by Nuclear Magnetic Resonance (NMR) and Fourier Transform infrared (FT-IR) spectroscopy. Algae-lysing activity was observed using microscopy. Results The algae-lysing bacterium LTH-2 isolated from Lake Taihu was identified as Serratia marcescens. Strain LTH-2 secreted a red pigment identified as prodigiosin (C20H25N30), which showed strong lytic activity with algal strains M. aeruginoso TH1, TH2, and FACHB 905 in a concentration-dependent manner. The 50% inhibitory concentration (ICs0) of prodigiosin with the algal strains was 4.8 (±0.4)×10^-2 μg/mL, 8.9 (±1.1)×10^-2μg/mL, and 1.7 (±0.1)×10^-1 μg/mL in 24 h, respectively. Conclusion The bacterium LTH-2 and its pigment related to damage of cell membranes. The bacterium for regulating blooms of harmful M. aeruginosa. had strong Microcystis-lysing activity probably LTH-2 and its red pigment are potentially useful 展开更多
关键词 Algicidal bacteria Microcystis aeruginosa Harmful algal blooms (HABs) Serratiamarcescens Algae-lysing
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NAA与营养液浓度对鹅掌柴根系及枝叶生长的影响 被引量:1
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作者 白孝明 马纪 +1 位作者 王雪娆 杨东霞 《湖北农业科学》 2019年第8期102-104,116,共4页
采用水培技术对鹅掌柴[Schefflera octophylla(Lour.) Harms]的根系进行快速诱导和枝叶生长研究,用不同浓度的NAA和营养液对鹅掌柴枝条进行处理,通过试验统计和方差分析得出水培鹅掌柴的根系生长的最适NAA和营养液浓度,其最适根系生长的... 采用水培技术对鹅掌柴[Schefflera octophylla(Lour.) Harms]的根系进行快速诱导和枝叶生长研究,用不同浓度的NAA和营养液对鹅掌柴枝条进行处理,通过试验统计和方差分析得出水培鹅掌柴的根系生长的最适NAA和营养液浓度,其最适根系生长的NAA浓度为15 mg/L,最适营养液浓度为200~300 mg/L,即为1/4配方标准液;水培鹅掌柴根系诱导成功后,在水培鹅掌柴后期生长及养护过程中,营养液浓度为500~600 mg/L,即为1/2配方标准液时,水培鹅掌柴的根系最发达且植株的枝叶最茂盛。说明,同一生长调节剂、同一营养液不同浓度下对水培鹅掌柴的影响存在较大差异。 展开更多
关键词 鹅掌柴[Schefflera octophylla(Lour.)Harms] 水培 NAA 营养液
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