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CNN-ERI地质识别模型的研究与应用
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作者 张腾 雷泉龙 +1 位作者 赵雨顺 华兴林 《黄河水利职业技术学院学报》 2024年第1期40-44,共5页
基建工程对地质勘探精度的要求不断提高,研究人工智能技术在地质勘探数据分析处理中的应用具有重要意义。基于卷积神经网络技术的数据降维处理功能,提出一种改进的CNN-ERI地质识别模型,分析了该模型在地质识别方面的优越性,探讨了数据... 基建工程对地质勘探精度的要求不断提高,研究人工智能技术在地质勘探数据分析处理中的应用具有重要意义。基于卷积神经网络技术的数据降维处理功能,提出一种改进的CNN-ERI地质识别模型,分析了该模型在地质识别方面的优越性,探讨了数据量和环境因素对模型识别精度的影响,并结合某隧洞工程,探析了模型的具体应用问题。 展开更多
关键词 高密度电法 卷积神经网络 数据降维处理功能 CNN-eri地质识别模型 地质特征 精度分析
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3'→5'核酸外切酶ERI-1调控多种RNA代谢的机制
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作者 张怡然 刘慧泉 +1 位作者 唐喆 金巧军 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2023年第1期6-17,共12页
ERI-1是一种3’→5’核糖核酸外切酶,具有一个类ERI-1_3’h Exo结构域和一个SAP结构域,在真核生物中保守存在。ERI-1最初是在筛选秀丽隐杆线虫ds RNA敏感性增强突变体时发现的,是RNAi的重要调节因子。ERI-1通过与外源性RNAi组分竞争Dice... ERI-1是一种3’→5’核糖核酸外切酶,具有一个类ERI-1_3’h Exo结构域和一个SAP结构域,在真核生物中保守存在。ERI-1最初是在筛选秀丽隐杆线虫ds RNA敏感性增强突变体时发现的,是RNAi的重要调节因子。ERI-1通过与外源性RNAi组分竞争Dicer协调内源RNAi和外源性RNAi,并促进特定内源性si RNA的生成,且该功能为线虫特有。其还通过核酸外切酶活性降解si RNA及mi RNA,负向调控RNAi。裂殖酵母ERI-1通过降解异染色质相关si RNA的水平,参与调控异染色质的形成。ERI-1在r RNA的加工和成熟中发挥重要作用。此外哺乳动物ERI-1在细胞周期S期末期降解组蛋白m RNA,从而推动细胞进入G2期。本文从结构、功能等方面概述了ERI-1调控多种RNA代谢的机制,探讨了其进化丢失问题和应用前景并对后续研究提出了建议。 展开更多
关键词 eri-1 RNA干扰 小干扰RNA
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两种不同技术PS给药对NRDS并呼吸困难早产儿肺功能及不良反应的影响
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作者 叶桂姣 郝艳萍 王莉萍 《中国计划生育学杂志》 2024年第9期2079-2084,2089,共7页
目的:对比不同技术肺表面活性物质(PS)给药联合咖啡因对新生儿呼吸窘迫综合征(NRDS)早产儿肺功能及不良反应的影响。方法:选取2019年8月-2023年8月本院收治的NRDS早产儿,随机数字表以简单随机法分为对照组(n=52)与观察组(n=53),对照组... 目的:对比不同技术肺表面活性物质(PS)给药联合咖啡因对新生儿呼吸窘迫综合征(NRDS)早产儿肺功能及不良反应的影响。方法:选取2019年8月-2023年8月本院收治的NRDS早产儿,随机数字表以简单随机法分为对照组(n=52)与观察组(n=53),对照组予以气管插管-使用肺表面活性物质-拔管技术(INSURE)PS给药联合咖啡因治疗,观察组采用微创肺表面活性物质给药技术(LISA)PS给药联合咖啡因治疗。比较两组治疗后24 h的疗效,患儿达到纠正年龄36周时的肺功能指标[潮气量(VT)、呼吸频率(RR)、分钟通气量(MV)、达峰时间比(TPTEF/TE)、达峰容积比(VPEF/VE)、25%、50%及75%潮气量时的呼气流速(FEF25%、FEF50%、FEF75%)]、治疗前与治疗后24h的呼吸力学指标[气道阻力、静态肺顺应性、内源性呼气末正压(PEEP)]、血气分析值[氧分压(PaO_(2))值、二氧化碳分压(PaCO_(2))值、pH]、患儿接受治疗的各项时间指标(呼吸困难消失时间、无创辅助通气总时间、住院时间)、用药期间不良反应及住院期间发症发生率。结果:治疗24h后,观察组疗效(94.3%)高于对照组(88.8%),患儿达到纠正年龄36周时RR、气道阻力与内源性PEEP低于对照组,MV、TPTEF/TE、VPEF/VE、FEF25%、FEF50%、FEF75%、静态肺顺应性均高于对照组,两组血气分析值部分指标均较治疗前有明显恢复,且观察组PaO_(2)与pH高于对照组,PaCO_(2)低于对照组(均P<0.05)。观察组住院时间(18.63±1.83d)少于对照组(20.57±2.07d)(均P<0.05)。各项不良反应及并发症的发生率两组无差别(P>0.05)。结论:INSURE技术与LISA技术PS给药联合咖啡因对NRDS早产儿均有一定疗效,但LISA技术疗效更好,对早产儿肺功能、呼吸功能及血气值均有良好影响,并能促进患儿康复,用药及住院期间未增加早产儿不良反应及并发症发生。 展开更多
关键词 新生儿呼吸窘迫综合征 早产儿 微创肺表面活性物质给药技术 气管插管-使用肺表面活性物质-拔管技术 肺表面活性物质 咖啡因 肺功能 不良反应
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四磨汤鼻饲对食管癌术后胃肠功能恢复的影响 被引量:1
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作者 夏传宝 《中国中医药现代远程教育》 2024年第6期52-54,共3页
目的 探究四磨汤经鼻空肠营养管鼻饲对食管癌术后胃肠功能恢复的影响。方法 选择2013年9月—2021年9月于福建中医药大学附属人民医院行食管癌手术的患者80例,采用随机数字表法分为研究组(40例)及对照组(40例)。所有患者均行食管癌根治术... 目的 探究四磨汤经鼻空肠营养管鼻饲对食管癌术后胃肠功能恢复的影响。方法 选择2013年9月—2021年9月于福建中医药大学附属人民医院行食管癌手术的患者80例,采用随机数字表法分为研究组(40例)及对照组(40例)。所有患者均行食管癌根治术,术后均给予常规肠内及肠外的营养支持。研究组术后应用四磨汤鼻饲治疗,对照组术后经鼻空肠营养管注入温生理盐水,2组患者均连续治疗7 d。对比2组胃肠功能恢复情况、中医证候积分及胃泌素水平。结果 治疗后,研究组胃肠功能恢复时间短于对照组、各中医证候积分低于对照组、胃泌素水平高于对照组,差异均有统计学意义(P<0.05)。结论 食管癌手术患者术后经鼻空肠营养管鼻饲四磨汤有助于确保胃肠激素稳定、促进胃肠功能恢复、缩短术后恢复时间,值得推广应用。 展开更多
关键词 食管癌 四磨汤 经鼻空肠营养管鼻饲 营养支持 胃肠功能恢复
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ERI-1缓蚀剂的合成及性能评价 被引量:6
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作者 申明周 《石油化工腐蚀与防护》 CAS 2002年第3期42-45,共4页
介绍了一种有机胺缓蚀剂的合成工艺及评价方法 ,并进行了缓蚀性能评定。试验结果表明 :ERI- 1是一种咪唑啉酰胺类吸附膜型缓蚀剂 ,能有效抑制电化学腐蚀的阴极过程 ,从而起到缓蚀作用。ERI- 1缓蚀剂受pH值波动影响小 。
关键词 eri-1缓蚀剂 合成 性能评价 有机胺缓蚀剂
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基于‖X‖*-α‖X‖_(F)模型张量恢复(L_(2),L_(1))-TRIP的条件
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作者 钟林江 王川龙 《太原师范学院学报(自然科学版)》 2024年第2期1-7,共7页
限制等距条件在稀疏优化中是稀疏性的保证.在压缩感知和矩阵补全中,基于L_(1),L_(*)以及L_(1)-L_(2)和L_(*)-L_(F)优化模型的限制等距条件已经推广到张量模型上,基于Tucker秩和L_(*)-αLF(0<α≤1)优化模型,在脉冲噪声的情况下研究... 限制等距条件在稀疏优化中是稀疏性的保证.在压缩感知和矩阵补全中,基于L_(1),L_(*)以及L_(1)-L_(2)和L_(*)-L_(F)优化模型的限制等距条件已经推广到张量模型上,基于Tucker秩和L_(*)-αLF(0<α≤1)优化模型,在脉冲噪声的情况下研究低秩张量X恢复的广义(L_(2),L_(1))-限制等距性质((L_(2),L_(1))-TRIP),并给出了低秩张量X恢复的充分条件以及恢复的误差. 展开更多
关键词 ‖X‖*-α‖X‖F最小化 限制等距性 低秩张量恢复 脉冲噪声
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论《园冶》思想在产业园区景观设计中的应用
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作者 栾河淞 《城市建筑空间》 2024年第6期13-18,共6页
“巧于因借、精在体宜”与“虽由人作、宛自天开”是《园冶》造园思想的典型代表,从物质层面与精神层面阐释园林营造理念的精髓。以丝路国际文化中心为例,探讨传统园林意趣对现代景观实践的启发,解析《园冶》思想在产业园区设计中的应用。
关键词 风景园林 产业园 借景 科创基因
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工作压力JDCS模型与ERI模型的结合对职业倦怠的影响
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作者 舒晓兵 《汉口学院学报》 2016年第1期1-6,共6页
JDCS和ERI模型是工作压力模型中两个重要的模型,为了探讨两个工作压力模型在中国社会背景下的适用性,本研究以企业员工为研究样本,对两个模型进行了比较并检验两者的结合的预测效度问题。研究结果显示JDCS模型各构念变量除社会支持... JDCS和ERI模型是工作压力模型中两个重要的模型,为了探讨两个工作压力模型在中国社会背景下的适用性,本研究以企业员工为研究样本,对两个模型进行了比较并检验两者的结合的预测效度问题。研究结果显示JDCS模型各构念变量除社会支持以外,工作要求和工作控制与职业倦怠的部分维度皆有显著相关。ERI模型各构念要素——工作付出、工作回报和工作过度投入与职业倦怠的部分维度皆有显著相关。ERI模型对职业倦怠的预测力要略高于JDCS模型,不仅表现在可解释的变异数值上,也表现在回归方程中显著预测变量的数量上。JDCS模型和ERI模型的结合对提高职业倦怠的预测力是有效的。 展开更多
关键词 JDcs模型 eri模型 工作要求 工作控制 工作过度投入 职业倦怠
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某市中学教师不同性别间ERI评分与高血压患病研究 被引量:1
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作者 马文奇 马丛花 +2 位作者 马月琴 贾磊娜 周健 《科技信息》 2014年第3期16-16,22,共2页
目的:探讨某市中学教师付出-回报失衡与高血压的关系。方法:采用分层整群抽样的研究方法,抽取从业时间≥2年的教师241人进行调查,排除了继发性高血压、糖尿病史、肝、肾病史等,确诊高血压病例28例,血压正常者213例。运用中文版的付出-... 目的:探讨某市中学教师付出-回报失衡与高血压的关系。方法:采用分层整群抽样的研究方法,抽取从业时间≥2年的教师241人进行调查,排除了继发性高血压、糖尿病史、肝、肾病史等,确诊高血压病例28例,血压正常者213例。运用中文版的付出-回报失衡问卷测评付出-回报失衡程度。结果:不同性别间各模块比较,女性自尊高于男性(p<0.05);担任班主任职务的教师自尊、社会控制和过度投入模块均高于不担任班主任职务的教师(p<0.05);男性教师和女性不同紧张水平组间高血压患病率比较,差异无统计学意义(p>0.05)。结论:中学教师存在一定的紧张程度,ERI与高血压不同性别之间无显著性差异,有待进一步研究。 展开更多
关键词 中学教师 eri 外在付出 社会控制 高血压
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Spatial Variations in Particle Size and Magnetite Concentration on Cedar Beach:Implications for Grain-Sorting Processes,Western Lake Erie,Canada 被引量:4
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作者 ZHANG Shuwei Maria T. CIOPPA ZHANG Shihong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1520-1532,共13页
This study examined spatial variations in the concentration,grain size and heavy mineral assemblages on Cedar Beach(Lake Erie,Canada).Magnetic studies of heavy mineral-enriched,dark-reddish sands present on the beac... This study examined spatial variations in the concentration,grain size and heavy mineral assemblages on Cedar Beach(Lake Erie,Canada).Magnetic studies of heavy mineral-enriched,dark-reddish sands present on the beach showed that magnetite(~150μm) is the dominant magnetic mineral.Surficial magnetic susceptibility values defined three zones:a lakeward region close to the water line(Zone 1),the upper swash zone(Zone 2) and the region landwards of the upper swash zone (Zone 3).Zone 2 showed the highest bulk and mass susceptibility(κ,χ) and the highest mass percentage of smaller grain-size(250μm) fractions in the bulk sand sample.Susceptibility(i.e.κandχ) values decreased and grain size coarsened from Zone 2 lakewards(into Zone 1) and landwards (into Zone 3),and correlated with the distribution of the heavy mineral assemblage,most probably reflecting preferential separation of large,less dense particles by waves and currents both along and across the beach.The eroded western section of Cedar Beach showed much higher concentrations of heavy minerals including magnetite,and finer sand grain sizes than the accreting eastern section, suggesting that magnetic techniques could be used as a rapid,cost-effective way of examining erosion along sensitive coastline areas. 展开更多
关键词 magnetic susceptibility magnetite concentration grain size grain-sorting processes Cedar Beach Lake erie
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Ecological Risk Assessment of World Heritage Sites Using RS and GIS:A Case Study of Huangshan Mountain, China 被引量:2
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作者 HUANG Shiman HU Qingwu +1 位作者 WANG Shaohua LI Haidong 《Chinese Geographical Science》 SCIE CSCD 2022年第5期808-823,共16页
Ecological risk assessment(ERA) is an indispensable method for systematic monitoring of World Heritage Sites(WHSs) exposed to various anthropogenic factors and natural disasters. Remote sensing(RS) and geographical in... Ecological risk assessment(ERA) is an indispensable method for systematic monitoring of World Heritage Sites(WHSs) exposed to various anthropogenic factors and natural disasters. Remote sensing(RS) and geographical information systems(GIS) can eliminate many limitations in traditional ERA methods. In this study, changes in ecological risk at Huangshan Mountain, the first mixed WHS in China, over the period of 1984–2019 were explored using remote sensing images and products by considering both natural disasters and human disturbance. Results show that of the four land cover types in Huangshan Mountain, namely water, forest, building and farmland, the main land cover type is forest. During the 35 yr, lands categorised at low or relatively low ecological risk levels are dominant in Huangshan Mountain, with the lowest and highest ERIs(ecological risk index) in 1990 and 2010, respectively. The areas at the five ecological risk levels have declined as follows: relatively low > low > medium > relatively high > high. Changes in ecological risks are closely related to changes in land cover and natural disasters. Even though major natural disasters may affect the ecological risk level in the whole region, changes in land cover caused by human activities will shift the ecological risk level in some areas. Our attempts can be modified and applied to other sites, and offer policy implications for protection and preservation of WHSs. 展开更多
关键词 ecological risk assessment ecological risk index(eri) world heritage site landscape ecological index Huangshan Mountain Remote Sensing
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Period investigation of Algol systems TZ Eri and TU Her 被引量:1
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作者 Zhi-Hua Wang Li-Ying Zhu +1 位作者 Lin-Jia Li Xiao-Man Tian 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第8期11-18,共8页
TZ Eri and TU Her are both classic Algol-type systems(Algols). By observing and collecting times of minimum light, we constructed the O-C curves for the two systems. The long-time upward and downward parabolas shown i... TZ Eri and TU Her are both classic Algol-type systems(Algols). By observing and collecting times of minimum light, we constructed the O-C curves for the two systems. The long-time upward and downward parabolas shown in these diagrams are considered to be the result of the combination of mass transfer and angular momentum loss. The secular orbital period change rates are d P/dt = 4.74(±0.12) ×10-7 d yr-1 and d P/dt =-2.33(±0.01) × 10-6 d yr-1, respectively. There are also cyclic variations in their O-C curves which might be caused by the light-travel time effect(LTTE). A circumbinary star may exist in the TZ Eri system with a mass of at least 1.34 M⊙, while there are possibly two celestial bodies that almost follow a 2 : 1 resonance orbit around the TU Her binary pair. Their masses are at least 2.43 M⊙and 1.27 M⊙. 展开更多
关键词 stars:binaries:close stars:binaries:eclipsing stars:individual (TZ eri TU Her)
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Studies on ecological characteristics variation and population dynamics of four lizardfishes in the southern Taiwan Straits 被引量:1
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作者 DU Jianguo LU Zhenbin +1 位作者 YANG Shengyun CHEN Mingru 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第6期72-81,共10页
The ecological characteristics of four lizardfishes, Trachinocephalus myops, Saurida undosquamis, Saurida tumbil and Saurida elongata, were studied from specimens (910 T. myops, 454 S. un-dosquamis, 686 S. tumbil and... The ecological characteristics of four lizardfishes, Trachinocephalus myops, Saurida undosquamis, Saurida tumbil and Saurida elongata, were studied from specimens (910 T. myops, 454 S. un-dosquamis, 686 S. tumbil and 744 S. elongata) collected monthly in the southern Taiwan Straits from April 2005 to March 2006. The population dynamics of the four lizardfishes was also discussed by the comparison with the previous studies. All being composed of 7 a classes; the dominant group of T. myops and S. tumbil was 1–2 a, while S. undosquamis and S. elongate were 2–3 a. The total mortality coefficient Z and the fishing mortality F were at high as indicated by the exploitation ratio E(0.5), and a large number of by-caught juvenile and young fishes showing that the stock of lizardfishes in this area was overexploited and the fishing gear was irrational. Compared with the previous studies, the maximum and mean fork length, body mass and age of the four lizard- fishes declined gradually, the lizardfishes populations were younger in age and smaller in size. The asymptotic fork length L ∞ decreased while increasing growth coefficient k, and age at the inflexion point of mass t r was younger compared with the previous studies. The declining of older ones has moderated the feeding competition and the younger ones grew faster. The larger mortality param-eters Z, M and F have revealed higher fishing pressure. The smaller change of the first mature fork length of female T . myops and the change from K selection pattern to r selection pattern of S. tumbil have indicated a more vulnerable fishery ecosystem in this area. The changes of ecological characteristics and population dynamics may be caused by over-exploitation of demersal fishes such as the lizardfishes, especially a large number of juvenile and young fishes by-catch by the current fishing gears and methods. Therefore, in addition to the traditional fishery management approach such as the minimum length-limit, ecosystem approach to fisheries management (EAF) should be taken to improve the practical marine ecosystem management, including increased fishing intensity of the non-economic species especially the feeding competitors of the lizardfishes and the conservation of the pelagic fishery population in the fisheries ecosystem, in order to restore the fishery population and achieve the sustainable use of the fishery stocks. 展开更多
关键词 lizardfish ecological parameters population dynamics ecosystem approach to fish- eries management southern Taiwan Straits
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Orbital period changes of the W UMa binary YY Eri 被引量:1
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作者 Ting Yu Ke Hu +1 位作者 Yun-Xia Yu Fu-Yuan Xiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第9期13-20,共8页
Orbital period changes of the W UMa-type binary YY Eri are analyzed by using all photoelectric and ccd times of light minimum. The results show that its orbital period is undergo- ing a secular increase superposed on ... Orbital period changes of the W UMa-type binary YY Eri are analyzed by using all photoelectric and ccd times of light minimum. The results show that its orbital period is undergo- ing a secular increase superposed on two cyclic oscillations. The continuous increase at the rate of dP/dt = 6.3806 × 10^-8 d yr^-1 may be accounted for by mass transfer from the less massive com- panion to the more massive one. Two periodic variations with periods of 38.6192 and 22.3573 yr may be attributed to the light-time effect of a faint third star and the cyclic magnetic activity of the system, respectively. 展开更多
关键词 STARS BINARIES close - stars BINARIES eclipsing - stars individual (YY eri
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Optimization of Pulse-Field Gel Electrophoresis for Borrelia burgdorferi Subtyping 被引量:2
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作者 GENG Zhen HOU Xue Xia +3 位作者 HAO Qin ZHOU Hai Jian WANG Feng WAN Kang Lin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第7期584-591,共8页
Objective To optimize the performance of Pulsed-Field Gel Electrophoresis (PFGE) for the comparison of inter-laboratory results and information exchange of Borrelia burgdorferi subtypingo Methods A panel of 34 strai... Objective To optimize the performance of Pulsed-Field Gel Electrophoresis (PFGE) for the comparison of inter-laboratory results and information exchange of Borrelia burgdorferi subtypingo Methods A panel of 34 strains of B. burgdorferi were used to optimize PFGE for subtyping. In order to optimize the electrophoretic parameters (EPs), all 34 strains of B. burgdorferi were analyzed using four EPs, yielding different Simpson diversity index (D) values and the epidemiological concordance was also evaluated. Results The EP of a switch time of l s to 25 s for13 h and l s to10 s for 6 h produced the highest D value and was declared to be optimal for Mlul and 5mal PFGE of B. burgdorferi. Mlul and Smal were selected as the first and second restriction enzymes for PFGE subtyping of B. burgdorferi according to discrimination and consistency with epidemiological data. Conclusion PFGE can be used as a valuable test for routine genospecies identification of B burgdorferi. 展开更多
关键词 Molecular subtyping Pulse-Field Gel Electrophoresis Borrelia burgdor^eri
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美陆军ERIS拦截器试射成功 被引量:1
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作者 许彤 《世界导弹与航天》 北大核心 1991年第6期36-36,39,共2页
1991年1月28日,美国对外大气层再入弹头拦截器分系统(ERIS)进行了一次试验。当时该拦截器从夸贾林岛靶场发射,模拟的来袭导弹则是从7770公里以外的范登堡空军基地发射的。试验过程中,ERIS拦截器借助雷达和卫星从假弹头中识别出模拟的来... 1991年1月28日,美国对外大气层再入弹头拦截器分系统(ERIS)进行了一次试验。当时该拦截器从夸贾林岛靶场发射,模拟的来袭导弹则是从7770公里以外的范登堡空军基地发射的。试验过程中,ERIS拦截器借助雷达和卫星从假弹头中识别出模拟的来袭核弹头,并在空间将其摧毁。 这一试验是与布什总统将战略防御计划(SDI) 展开更多
关键词 eriS 拦截器 拦截导弹 发射
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Spatial Variations in Particle Size,Heavy Mineral Assemblage and Magnetic Concentration of Dark-reddish Sands on Cedar Beach,Western Lake Erie,Ontario,Canada
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作者 Maria T.Cioppa 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期124-124,共1页
Environmental magnetic research on beaches and shoreline processes is limited.Therefore,we carried out environmental magnetic studies on the heavy mineral-enriched,dark-reddish sands on Cedar Beach of western Lake Eri... Environmental magnetic research on beaches and shoreline processes is limited.Therefore,we carried out environmental magnetic studies on the heavy mineral-enriched,dark-reddish sands on Cedar Beach of western Lake Erie(41.68°N,82.40°W).Magnetite has been identified as the dominant magnetic mineral of these sands.This study reveals a spatial variation in concentration of magnetite particles,distribution of 展开更多
关键词 heavy mineral MAGNETIC CONCENTRATION grain size dark-reddish SANDS cross-shore and lonshore variation Cedar BEACH Lake erie
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Role of Suspended Sediments and Mixing in Reducing Photoinhibition in the Bloom-Forming Cyanobacterium Microcystis
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作者 Justin D. Chaffin Thomas B. Bridgeman +1 位作者 Scott A. Heckathorn Ann E. Krause 《Journal of Water Resource and Protection》 2012年第12期1029-1041,共13页
Toxic cyanobacterial blooms are becoming a global problem. Previous research of cyanobacterial bloom development has examined how high nutrient concentrations promote cyanobacteria dominance, and how positive buoyancy... Toxic cyanobacterial blooms are becoming a global problem. Previous research of cyanobacterial bloom development has examined how high nutrient concentrations promote cyanobacteria dominance, and how positive buoyancy provides an ecological advantage over sinking phytoplankton. Tributaries responsible for loading nutrients into lakes often simultaneously contribute high concentrations of suspended sediments. High concentrations of suspended sediments may also influence blooms by affecting the ambient light climate, reducing photodamage, and increasing the efficiency of photosynthesis. We examined the effects of sediments and vertical mixing in potentially reducing photodamage to Microcystis by measuring photosynthetic parameters and pigment content of Microcystis in western Lake Erie during the 2008 bloom and in laboratory experiments. Photosynthetic efficiency increased with increasing sediment concentration in the lake and laboratory experiment. Content of photo-protective carotenoid pigments per dry weight decreased with increasing sediment concentrations, while the light-harvesting pigments, chl a and phycocyanin, increased with sediments. These results indicate that suspended sediments reduce photoinhibition for Microcystis. Further, photosynthetic damage was higher when Microcystis was concentrated on the surface compared to a mixed water column. Measurements of Microcystis abundance and light were also recorded, in addition to photosynthetic measurements. Greatest Microcystis abundances in Lake Erie were recorded during light-limiting conditions, which offer Microcystis both physiological and ecological benefits by reducing photoinhibition and increasing Microcystis’ advantage in light competition via buoyancy. Efforts to reduce cyanobacterial blooms may include reducing suspended sediments loads in combination with reducing nutrient loading. 展开更多
关键词 Chlorophyll Fluorescence CYANOBACTeriA Harmful ALGAE BLOOM Lake erie MICROCYSTIS Suspended Sediments
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ERI公司部署了新的公司总部
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作者 刘全勇(译) 《现代化工》 CAS CSCD 北大核心 2010年第3期95-95,共1页
EnergyRecovery公司(ERI)在加利福利亚SanLearndro地区附近重新部署了它的公司总部和生产活动,这将包括最新的陶瓷研发和生产。
关键词 eri公司 公司总部 生产活动 生产能力
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Analysis of Convective Transport of Temperature-Dependent Viscosity forNon-Newtonian Erying Powell Fluid: A Numerical Approach
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作者 Ahlam Aljabali Abdul Rahman Mohd Kasim +2 位作者 Nur Syamilah Arifin Sharena Mohamad Isa Noor Amalina Nisa Ariffin 《Computers, Materials & Continua》 SCIE EI 2021年第1期675-689,共15页
Non-Newtonian is a type of fluid that does not comply with the viscosity under the Law of Newton and is being widely used in industrial applications.These include those related to chemical industries,cosmetics manufac... Non-Newtonian is a type of fluid that does not comply with the viscosity under the Law of Newton and is being widely used in industrial applications.These include those related to chemical industries,cosmetics manufacturing,pharmaceutical field,food processing,as well as oil and gas activities.The inability of the conventional equations of Navier–Stokes to accurately depict rheological behavior for certain fluids led to an emergence study for non-Newtonian fluids’models.In line with this,a mathematical model of forced convective flow on non-Newtonian Eyring Powell fluid under temperature-dependent viscosity(TDV)circumstance is formulated.The fluid model is embedded with the Newtonian heating(NH)boundary condition as a heating circumstance and is assumed to move over a stretching sheet acting vertically.Using appropriate similarity variables,the respective model was converted into ordinary differential equations(ODE),which was later solved utilizing the Keller box approach.The present model is validated by comparing the existing output in literature at certain special limiting cases,where the validation results display a firm agreement.The current outputs for the proposed model are shown in tabular and graphical form for variation of skin friction plus Nusselt number,velocity and temperature distribution,respectively. 展开更多
关键词 Temperature-dependent viscosity erying powell fluid vertical stretching sheet numerical solution boundary layer
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