检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

东海中南部澳洲鲐繁殖群体生物学特征

中国水产科学 2024年第4期31卷 429-438页

作者：史雨楠严利平李建生中国水产科学研究院东海水产研究所农业农村部东海渔业资源开发利用重点实验室上海海洋大学海洋科学学院

为研究东海海域澳洲鲐(Scomberaustralasicus)繁殖群体的生物学特征,依据2016—2023年1—4月在东海中南部采集的227尾澳洲鲐样本,分析了澳洲鲐繁殖群体的叉长、体重、摄食等级、肥满度、性腺指数、性比及肌肉含量等生物学特征。结果显示... 详细信息

为研究东海海域澳洲鲐(Scomberaustralasicus)繁殖群体的生物学特征,依据2016—2023年1—4月在东海中南部采集的227尾澳洲鲐样本,分析了澳洲鲐繁殖群体的叉长、体重、摄食等级、肥满度、性腺指数、性比及肌肉含量等生物学特征。结果显示,澳洲鲐繁殖群体性别间的叉长和体重关系无显著差异(P>0.05),雌雄个体合并拟合的叉长和体重关系式为:W=3×10–6FL3.2558。1月为澳洲鲐的越冬期, 2—4月为繁殖期。澳洲鲐的产卵高峰期集中在3月,到4月下旬,已经产卵的澳洲鲐数量比例增大。在性腺发育同等情况下,雌性澳洲鲐在繁殖期间性腺指数始终高于雄性澳洲鲐,而肌肉含量却小于雄性澳洲鲐。摄食强度在越冬期到繁殖期前后是先下降后上升的状态,肥满度则是先上升后下降,最后恢复到与繁殖期前相近的水平。2月繁殖初期雄性多于雌性,到3—4月繁殖中后期雌性数量多于雄性。这种繁殖期间性比的变化符合最大限度实现世代补充和繁殖收益最大化的繁殖策略。综上,东海中南部澳洲鲐的繁殖高峰期集中在3月,在进入繁殖期后,性腺发育过程中会减少摄食,生长缓慢,机体的部分肌肉组织会转化为性腺以满足生殖所需。

关键词：澳洲鲐繁殖群体生物学特征东海

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

面向无人机绝对定位的遥感影像快速检索方法

中国惯性技术学报 2024年第4期32卷 363-370,378页

作者：王小攀李建胜王安成杨子迪信息工程大学地理空间信息学院郑州450000 河南机电职业学院郑州450000

针对在复杂环境下无人机景象匹配导航中的视觉绝对定位问题,提出了一种聚合深度学习特征的实时影像快速检索方法。首先,引入可训练软分配深度学习框架—NetVLAD,结合VGG16网络提取并聚合生成影像稳定的全局特征表达向量;其次,在初始检... 详细信息

针对在复杂环境下无人机景象匹配导航中的视觉绝对定位问题,提出了一种聚合深度学习特征的实时影像快速检索方法。首先,引入可训练软分配深度学习框架—NetVLAD,结合VGG16网络提取并聚合生成影像稳定的全局特征表达向量;其次,在初始检索阶段,使用KD树结构对影像全局特征向量构建检索索引,在不损失检索精度的前提下提高检索速度;最后,使用皮尔逊积矩相关系数对初始检索结果进行快速预判断,自动过滤初始检索结果,对于需要重排序的影像则采用特征学习匹配算法——图神经网络SuperGlue进行匹配重排序。所提方法在公开的夏季和冬季遥感影像数据集分组进行实验,实验结果表明:未重排序条件下,初始检索结果第一张影像平均准确率达到了58.27%,部分特征较好地区准确率达到了85%,对不同时相遥感影像也有很好的适应性,平均检索一张影像耗时3.7 s,可为无人机景象匹配导航的初始定位提供参考。

关键词：遥感软分配影像检索聚合景象匹配

Simultaneous pyridine biodegradation and nitrogen removal in an aerobic granular system

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2018年第5期30卷 318-329页

作者： Xiaodong liu Shijing Wu Dejin Zhang Jinyou Shen Weiqing Han Xiuyun Sun jiansheng li lianjun Wang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science and Technology

Simultaneous pyridine biodegradation and nitrogen removal were successfully achieved in a sequencing batch reactor（SBR） based on aerobic granules. In a typical SBR cycle, nitritation occurred obviously after the majority of pyridine was removed, while denitrification occurred at early stage of the cycle when oxygen consumption was aggravated. The effect of several key operation parameters, i.e., air flow rate, influent NH4~＋-N concentration,influent p H and pyridine concentration, on nitritation, pyridine degradation and total nitrogen（TN） removal, was systematically investigated. The results indicated that high air flow rate had a positive effect on both pyridine degradation and nitritation but a negative impact of overhigh air flow rate. With the increase of NH4~＋ dosage, both nitritation and TN removal could be severely inhibited. Slightly alkaline condition, i.e., pH 7.0–8.0, was beneficial for both pyridine degradation and nitritation. High pyridine dosage often resulted in the delay of both pyridine degradation and nitritation. Besides, extracellular polymeric substances production was affected by air flow rate, NH4~＋ dosage, pyridine dosage and p H.In addition, high-throughput sequencing analysis demonstrated that Bdellovibrio and Paracoccus were the dominant species in the aerobic granulation system. Coexistence of pyridine degrader, nitrification related species, denitrification related species, polymeric substances producer and self-aggregation related species was also confirmed by highthroughput sequencing.

关键词： Aerobic granule Biodegradation Nitritation Denitrification Pyridine

在线全文

学校读者我要写书评

暂无评论

清醒俯卧位在急性低氧性呼吸衰竭中的应用

中华危重病急救医学 2024年第3期36卷 331-331页

作者：蒋佳维(编译) 陆军军医大学大坪医院战伤感染与特需药品研究室，创伤与化学中毒全国重点实验室，重庆 400042 中国人民解放军联勤保障部队第九二六医院，云南开远 661600

在患有中重度急性呼吸窘迫综合征(ARDS)的插管患者中,俯卧位可减少肺内分流并产生肺复张,优化通气/血流比值,减少肺泡死腔并降低右心室后负荷,从而提高中重度ARDS插管患者的生存率。但很少有研究探讨俯卧位对有自主呼吸且存在急性低氧... 详细信息

在患有中重度急性呼吸窘迫综合征(ARDS)的插管患者中,俯卧位可减少肺内分流并产生肺复张,优化通气/血流比值,减少肺泡死腔并降低右心室后负荷,从而提高中重度ARDS插管患者的生存率。但很少有研究探讨俯卧位对有自主呼吸且存在急性低氧性呼吸衰竭患者的生理影响。近期有意大利学者进行了一项序贯、交叉试验,旨在全面评估清醒俯卧位对急性低氧性呼吸衰竭患者生理反应(包括气体交换、呼吸努力、肺容量和充气模式)的影响。研究共纳入了15例急性低氧性呼吸衰竭且氧合指数(PaO2/FiO2)li)、肺顺应性、气道阻力、时间常数、动态应变(VT/EEli)及使用电阻抗断层扫描的Pendelluft程度。

关键词：动脉血气分析气道阻力俯卧位肺顺应性肺容量仰卧位驱动压交叉试验

Genetic dissection of carotenoids in maize kernels using high-density single nucleotide polymorphism markers in a recombinant inbred line population

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2017年第1期5卷 63-72页

作者： Orawan Jittham Xiuyi Fu Jing Xu Subhash Chander jiansheng li Xiaohong Yang National Maize Improvement Center of China/Beijing Key Laboratory of Crop Genetic Improvement/China Agricultural University Beijing 100193China

Carotenoids are antioxidants and vitamin A precursors that have important roles in human health. Hence, improving the carotenoid contents in maize kernels is a priority objective for breeders in order to obtain nutritional biofortification outcomes. In the current study, the genetic architecture of carotenoids in maize kernels was explored using a recombinant inbred line(RIL) population derived from a cross between inbred lines By804 and B73. A total of 81 QTLs were detected by using a high-density bin map and a simple sequence repeat(SSR)-based linkage map, with one to seven QTLs for each trait explaining 4.21%–47.53% of the phenotypic variation. A comparison of the QTL mapping efficiency between the two linkage maps revealed that the high-density bin map had higher resolution. In the current study 46 additional QTLs were identified, with 16 being common with previous studies and14 newly identified. Among the results, 29.6%(24/81) of QTLs explained > 10% of the phenotypic variation in the RIL population, and 70.4%(57/81) explained ≤ 10%. These results suggest that a few large-effect QTLs, together with a variable number of minor-effect QTLs,contributed to most of the genetic components of carotenoids in maize kernels.

关键词： Carotenoids QTL mapping SNP SSR Zea mays

Removal of phosphate from wastewater using alkaline residue

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2014年第5期26卷 970-980页

作者： Yubo Yan Xiuyun Sun Fangbian Ma jiansheng li Jinyou Shen Weiqing Han Xiaodong liu lianjun Wang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological Engineering Nanjing University of Science and Technology

Alkaline residue （AR） was found to be an efficient adsorbent for phosphate removal from wastewater. The kinetic and equilibrium of phosphate removal were investigated to evaluate the performance of modified alkaline residue. After treatment by NaOH （AR-NaOH）, removal performance was significantly improved, while removal performance was almost completely lost after treatment by HCI （AR-HC1）. The kinetics of the removal process by all adsorbents was well characterized by the pseudo second-order model. The Langmuir model exhibited the best correlation for AR-HC1, while AR was effectively described by Freundlich model. Both models were well fitted to AR-NaOH. The maximum adsorption capacities calculated from Langmuir equation were in following manner： AR-NaOH 〉 AR 〉 AR-HC1. Phosphate removal by alkaline residue was pH dependent process. Mechanisms for phosphate removal mainly involved adsorption and precipitation, varied with equilibrium pH of solution. For AR-HCI, the acid equilibrium pH （〈 6.0） was unfavorable for the formation of Ca-P precipitate, with adsorption as the key mechanism for phosphate removal. In contrast, for AR and AR- NaOH, precipitation was the dominant mechanism for phosphate removal, due to the incrase on pH （〉 8.0） after phosphate removal. The results of both XRD and SEM analysis confirmed CaHPOa.2H20 formation after phosphate removal by AR and AR-NaOH.

关键词： alkaline residue chemical modification phosphate removal adsorption precipitation

Hardening after annealing in nanostructured 316L stainless steel

在线全文

学校读者我要写书评

暂无评论

Nano Materials Science 2020年第1期2卷 80-82页

作者： Zhongchen Zhou Shuaizhuo Wang jiansheng li Yusheng li Xiaolei Wu Yuntian Zhu Nano and Heterogeneous Materials Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing210094China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China Department of Materials Science and Engineering North Carolina State UniversityRaleighNC27695USA

In this work,coarse-grained 316 L stainless steels were cold rolled with a thickness reduction of^83%(CR 83%).After annealing,the behaviors of the nanostructured stainless steel samples were systematically investigated in the temperatures range of 200C–650C.It was found that with increasing annealing temperature the volume fraction of theα0-martensite first increased to reach a maximum value at 400C,then the volume fraction decreased with further increases of the annealing temperature.The yield strength was increased from 1400 MPa to 1720 MPa after annealing;this strong hardening effect in cold rolled 316 L stainless steel was mainly attributed to the increase of the volume fraction ofα0-martensite.

关键词： Metals and alloys Nanostructure Heterostructure 316L stainless steel Annealing hardening Martensitic transformation

Reductive transformation and detoxification mechanism of 2,4-dinitrochlorobenzene in combined zero valent iron and anaerobic-aerobic process

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2012年第11期24卷 1900-1907页

作者： Jinyou Shen Zongyuan Zhou Changjin OU Xiuyun Sun jiansheng li Weiqing Han lin Zhou lianjun Wang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing 210094China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

A combined zero valent iron （ZVI） and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene （DNCB）- containing wastewater. The transformation pathway, reduction of acute toxicity and enhancement of biodegradability were investigated, After pretreatment by ZVI, DNCB in wastewater could be completely converted into 2,4-diaminochlorobenzene （DACB）. The ratio of BODs/COD increased from 0.005±0.001 to 0.168±0.007, while EC50,48hr （V/V） increased from 0.65% to 5.20%, indicating the enhancement of biodegradability and reduction of acute toxicity with the pretreatment by ZVI. DACB was further dechlorinated to m-phenylenediamine during the anaerobic process using methanol as electron donor, with EC50＇ 48 hr increasing from 5.20% to 48.2%. After the subsequent anaerobic-aerobic process, m-phenylenediamine was degraded completely, with effluent COD of 67.5±10.8 mg/L. This effluent of the subsequent anaerobic-aerobic process was not toxic to zebrafish. The combined ZVI and anaerobic-aerobic process offers bright prospects for the treatment of chlorinated nitroaromatic compound-containing wastewater.

关键词： 2,4-dinitrochlorobenzene zero-valent iron toxicity biodegradability

Transcriptome analysis of near-isogenic lines provides molecular insights into starch biosynthesis in maize kernel

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2016年第8期58卷 713-723页

作者： Yingni Xiao Shawn Thatcher Min Wang Tingting Wang Mary Beatty Gina Zastrow-Hayes lin li jiansheng li Bailin li Xiaohong Yang National Maize Improvement Center of China Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100193 China DuPont Pioneer 200 Powder Mill Road Wilmington DE 19880 USA College of Agronomy Northwest Agricultural and Forest University Yang Ling 712100 China DuPont Pioneer Johnston Iowa 50131 USA Department of Agronomy and Plant Genetics University of Minnesota St. Paul Minnesota 55108 USA.

Starch is the major component in maize kernels,providing a stable carbohydrate source for humans and livestock as well as raw material for the biofuel industry.Increasing maize kernel starch content will help meet industry demands and has the potential to increase overall yields.We developed a pair of maize near-isogenic lines（NILs） with different alleles for a starch quantitative trait locus on chromosome 3（q HS3）, resulting in different kernel starch content. To investigate the candidate genes for q HS3 and elucidate their effects on starch metabolism, RNA-Seq was performed for the developing kernels of the NILs at 14 and 21 d after pollination（DAP）. Analysis of genomic and transcriptomic data identified 76 genes with nonsynonymous single nucleotide polymorphisms and 384 differentially expressed genes（DEGs） in the in trogressed fragment, including a hexokinase gene, Zm HXK3 a, which catalyzes the conversion of glucose to glucose-6-phosphate and may play a key role instarch metabolism. The expression pattern of all DEGs in starch metabolism shows that altered expression of the candidate genes for q HS3 promoted starch synthesis,with positive consequences for kernel starch content. These results expand the current understanding of starch biosynthesis and accumulation in maize kernels and provide potential candidate genes to increase starch content.

关键词： Coexpression network maize quantitative trait loci RNA-Seq starch content