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5G Features from Operation Perspective and Fundamental Performance Validation by Field Trial 被引量:2
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作者 Guangyi Liu Yuhong Huang +2 位作者 Fei Wang Jianjun Liu Qixing Wang 《China Communications》 SCIE CSCD 2018年第11期33-50,共18页
The fast deployment and penetration of 4 G has cultivated human behaviors on mobile data consumption, leading to explosive growth in mobile traffic and stimulating new requirements on the capabilities of mobile networ... The fast deployment and penetration of 4 G has cultivated human behaviors on mobile data consumption, leading to explosive growth in mobile traffic and stimulating new requirements on the capabilities of mobile networks. To meet the requirements of mobile networks toward year 2020, the next generation of mobile networks(termed as IMT-2020, or 5 G) is designed to support 100 Mbps–1 Gbps user-experienced data rate, 1 ms radio transmission latency, and 1 million connections per square kilometer. Recalling the vision and requirements of 5 G targeting for commercial launch in 2020, this article overviews the key features of 5 G and compares with those of 4 G, and reports the world first field trials conducted to validate the key performance of 5 G radio interface in 3.5 GHz band. The trial results show that a 1 ms transmission latency and 1 Gbps data rate are achievable. 展开更多
关键词 试用 表演 操作 特征 活动网络 GBPS 人的行为 数据率
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Field Trials of CpGV Virus Isolates Overcoming Resistance to CpGV-M
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作者 M. Berling J. -B. Rey +5 位作者 S. -J. Ondet Y. Tallot O. Soubabère A. Bonhomme B. Sauphanor M. Lopez-Ferber 《Virologica Sinica》 SCIE CAS CSCD 2009年第5期470-477,共8页
The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France... The Cydia pomonella granulovirus (CpGV) has been used for many years as biological agent for codling moth control in apple orchards. Resistance to the Mexican strain of CpGV was detected in orchards in Germany, France and Italy. A laboratory insect colony was started from insects collected in a French resistant orchard. It was named RGV. Various virus isolates were identified as active against this resistant insect colony. Field tests were carried out in 2007 to test if the two virus isolates CpGV-I12 and NPP-R1 were effective in the field. Although these virus isolates were not able to reduce insect caused fruit damages, they significantly reduced the overwintering insect populations. NPP-R1 was subjected to eight passages on RGV larvae (NPP-R1.8) that improved its biological activity on RGV larvae. 2008 field trials were set up to test this improved virus strain, compared to CpGV-I12 and Madex plus active on RGV. These tests confirmed the ability to control both in susceptible and resistant insect populations. 展开更多
关键词 田间试验 病毒株 阻力 昆虫种群 有轨小车 苹果蠹蛾 颗粒体病毒 苹果园
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Lignin engineering in forest trees: From gene discovery to field trials 被引量:3
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作者 Barbara De Meester Ruben Vanholme +1 位作者 Thatiane Mota Wout Boerjan 《Plant Communications》 SCIE 2022年第6期1-25,共25页
Wood is an abundant and renewable feedstock for the production of pulp,fuels,and biobased materials.However,wood is recalcitrant toward deconstruction into cellulose and simple sugars,mainly because of the presence of... Wood is an abundant and renewable feedstock for the production of pulp,fuels,and biobased materials.However,wood is recalcitrant toward deconstruction into cellulose and simple sugars,mainly because of the presence of lignin,an aromatic polymer that shields cell-wall polysaccharides.Hence,numerous research efforts have focused on engineering lignin amount and composition to improve wood processability.Here,we focus on results that have been obtained by engineering the lignin biosynthesis and branching pathways in forest trees to reduce cell-wall recalcitrance,including the introduction of exotic lignin monomers.In addition,we draw general conclusions from over 20 years of field trial research with trees engineered to produce less or altered lignin.We discuss possible causes and solutions for the yield penalty that is often associated with lignin engineering in trees.Finally,we discuss how conventional and new breeding strategies can be combined to develop elite clones with desired lignin properties.We conclude this review with priorities for the development of commercially relevant lignin-engineered trees. 展开更多
关键词 LIGNIN genetic engineering BREEDING CRISPR field trial forest trees
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NATIONAL FIELD TRIAL OF THE CHINESE CLASSIFICATION AND DIAGNOSTIC CRITERIA OF MENTAL DISORDERS: COMPREHENSIBILITY, ACCEPTABILITY AND APPLICABILITY 被引量:1
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作者 张明圆 杨德森 +2 位作者 金华 吴文源 何燕玲 《Chinese Medical Journal》 SCIE CAS CSCD 1994年第2期46-50,共5页
The Chinese Neurology and Psychiatry Association conducted a national field trial of its Chinese Classification and Diagnostic Criteria of Mental Disorders (CCMD-2) involov-ing 26 provinces and municipalities, 80 psyc... The Chinese Neurology and Psychiatry Association conducted a national field trial of its Chinese Classification and Diagnostic Criteria of Mental Disorders (CCMD-2) involov-ing 26 provinces and municipalities, 80 psychiatric institutes, and 224 professionals. The results were as follows: (1)95.2% of researchers considered the comprehensibility of the CCMD-2 diagnstic criteria good. Within the ten major categories, comprehensibility ranged from 85.7% to 100%. (2) Of those surveyed concerning the acceptibility of the CCCMD-2 diagnostic criteria, 85.9% considered them acceptable. In individual classifications, the rate ranged from 74.1% to 95.2%. (3) 1498 cases were tested. The overall applicability rate which indicated the consistency between the CCMD-2 result and the actual clinical diagnoses was found to be 87.6%, (averaging Kappa = 0.82,P<0.01), better than those obtained from non-Chinese systems of diagnosis. 展开更多
关键词 DSM ACCEPTABILITY AND APPLICABILITY COMPREHENSIBILITY NATIONAL field trial OF THE CHINESE CLASSIFICATION AND DIAGNOSTIC CRITERIA OF MENTAL DISORDERS
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Field Trial of 40 Gbit/s ETDM Prototype System over 219 km of Installed Single Mode Fiber
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作者 Sang Soo Lee Hyun Woo Cho +6 位作者 Sang Kyu Lim Ki Ho Han Jin Soo Han Moo Jung Chu Je Soo Ko Kyeong-Mo Yoon Yong-Gi Lee 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期659-660,共2页
Transmission of 40Gbit/s NRZ signal was successfully demonstrated over 219km of installed SMF in KT's Daejeon area network. After transmission, the measured power penalty was 0.5dB for all the tributary channels.
关键词 of ET BE OVER field trial of 40 Gbit/s ETDM Prototype System over 219 km of Installed Single Mode Fiber
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Geo-Coordinated Parallel Coordinates (GCPC): Field trial studies of environmental data analysis
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作者 Maha El Meseery Orland Hoeber 《Visual Informatics》 EI 2018年第2期111-124,共14页
The large number of environmental problems faced by society in recent years has driven researchers to collect and study massive amounts of data in order to understand the complex relations that exist between people an... The large number of environmental problems faced by society in recent years has driven researchers to collect and study massive amounts of data in order to understand the complex relations that exist between people and the environment in which we live.Such datasets are often high dimensional and heterogeneous in nature,with complex geospatial relations.Analysing such data can be challenging,especially when there is a need to maintain spatial awareness as the non-spatial attributes are studied.Geo-Coordinated Parallel Coordinates(GCPC)is a geovisual analytics approach designed to support exploration and analysis within complex geospatial environmental data.Parallel coordinates are tightly coupled with a geospatial representation and an investigative scatterplot,all of which can be used to show,reorganize,filter,and highlight the high dimensional,heterogeneous,and geospatial aspects of the data.Two sets of field trials were conducted with expert data analysts to validate the real-world benefits of the approach for studying environmental data.The results of these evaluations were positive,providing real-world evidence and new insights regarding the value of using GCPC to explore among environmental datasets when there is a need to remain aware of the geospatial aspects of the data as the non-spatial elements are studied. 展开更多
关键词 Geovisual analytics Heterogeneous data visualization High dimensional data visualization field trial evaluations
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The Field Efficacy Trial of Several Fungicides for Controlling Rice Sheath Blight Disease (Rhizoctonia solani)
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作者 Huang Xianliang Jiang Xianya +4 位作者 Chen Maotuo Huang Riliang Wu Shangxin Lu Xixu Yang Jianyuan 《Plant Diseases and Pests》 CAS 2020年第3期18-20,30,共4页
[Objective]The paper was to study the field fficacy of several fumgicide against rice sheath bligh(Rhicoetonia solm).[Method]Field efficacy trial was performed with three novel fungicides,75%tebuconazole.azxytrobin WG... [Objective]The paper was to study the field fficacy of several fumgicide against rice sheath bligh(Rhicoetonia solm).[Method]Field efficacy trial was performed with three novel fungicides,75%tebuconazole.azxytrobin WG,75%tifloxystrobion-tebuconazole WG and 24%6 thi-fluzamide sC,while 30%difenoconazole-propiconazole EC and 10%jingangmyein AS,which had been Long circulated in production,were uwsed as contrl agents.[Result]The three novel fungicides had better control ffe on sheath blight than the control agents;75%tebuconazole.azoxys-trobin WG at the dase of 20 g/667 m2 received the best contrl efect,and the control efect was still 87.72%at 20 d post administration,and the yield increase efect was remarkable.The control efects of 75%tiloxystrobin-tebuconazole wG and 24%thifluzamide SC were 85.67%and 87.36%,repectively.[Conclusion]75%tebuconazole.azxoxystrobin wG,75%tifloxystrobin tebuconazole WC and 24%thiluamide SC could be promted as rotation fungicides to control rice sheath blight. 展开更多
关键词 RICE Sheath blight FUNGICIDE field trial
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滋养节杆菌S17的分离鉴定及其对黄瓜促生能力研究 被引量:1
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作者 曾先锋 孙钰晨 +4 位作者 谢学文 石延霞 柴阿丽 李宝聚 李磊 《中国生物防治学报》 CSCD 北大核心 2024年第1期178-185,共8页
为筛选出具有促生效果的生防细菌,本研究从河北、山东等地采集土样,分离筛选具有高产IAA能力的促生菌株,基于形态学特征、生理生化指标及多基因系统发育树分析,对潜在具有促生能力的菌株进行鉴定。同时测定促生菌株对黄瓜种子出芽及在... 为筛选出具有促生效果的生防细菌,本研究从河北、山东等地采集土样,分离筛选具有高产IAA能力的促生菌株,基于形态学特征、生理生化指标及多基因系统发育树分析,对潜在具有促生能力的菌株进行鉴定。同时测定促生菌株对黄瓜种子出芽及在盆栽试验、田间试验中对黄瓜幼苗的促生效果。结果表明:分离并鉴定出1株对黄瓜幼苗具有显著促生效果的细菌,滋养节杆菌ArthrobacterpascensS17。在DF+培养基中滋养节杆菌S17可大量合成IAA,其合成的IAA含量最高为128.54μg/mL。使用滋养节杆菌S17灌根处理,对黄瓜幼苗株高的增长率达到35.99%、对黄瓜幼苗叶面积的增长率达到26.90%,黄瓜幼苗各项生理指标均显著高于对照。滋生节杆菌S17对黄瓜促生效果显著,具有一定的开发应用前景。 展开更多
关键词 滋养节杆菌 鉴定 促生 种子处理 田间试验
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不同声音对草鱼幼鱼负趋音性行为反应影响研究
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作者 何晨睿 李晓兵 +8 位作者 达瓦 尼玛旦增 张占 王艳 占慧芬 刘媛媛 胡晓 石小涛 刘国勇 《渔业科学进展》 CSCD 北大核心 2024年第4期86-96,共11页
声驱鱼技术作为辅助过鱼措施之一,承担着保证鱼类洄游顺利通过过鱼设施,继而保护鱼类资源和恢复河流连通性的重要作用。本研究采用交替播音的形式,以草鱼(Ctenopharyngodon idellus)幼鱼为研究对象进行负趋音性实验,旨在探究草鱼幼鱼面... 声驱鱼技术作为辅助过鱼措施之一,承担着保证鱼类洄游顺利通过过鱼设施,继而保护鱼类资源和恢复河流连通性的重要作用。本研究采用交替播音的形式,以草鱼(Ctenopharyngodon idellus)幼鱼为研究对象进行负趋音性实验,旨在探究草鱼幼鱼面对不同声音的行为反应。实验水槽(3.6 m×1.1 m×1.0 m)布置于下牢溪周围水域,平均水深为0.5 m,平均流速为0.06 m/s。实验使用1种单频音(1 000 Hz)和5种复杂音(鱼游动声、引擎声、短吻鳄叫声、打桩声和游艇声),声压级(sound pressure level)为(117.69±2.77) dB re 1μPa,对照组为未播放声音时草鱼的行为反应数据。结果显示,播放复杂音时,草鱼的反应次数、趋音速度、运动时间比均显著高于单频音和对照组(P<0.001),草鱼的初次反应时间、平均反应时间均显著低于单频音和对照组(P<0.001);复杂音中,受到游艇声刺激的草鱼反应次数和趋音速度最大,受到鱼游动声刺激的草鱼反应次数、趋音速度最小;复杂音中,受到游艇声刺激的草鱼初次反应时间最短,为(23.40±5.13)s;受到引擎声刺激的草鱼初次反应时间最长,为(146.00±7.82) s,显著低于其他复杂音(P<0.05);受到游艇声和打桩声刺激的草鱼平均反应时间最短,分别为(26.52±3.01) s和(28.76±4.07) s;受到鱼游动声刺激的草鱼平均反应时间最长,为(64.76±17.82)s;复杂音中,受到鱼游动声刺激的草鱼运动时间比最高,为(98.47±0.48)%;受到引擎声刺激的草鱼运动时间比最低,为(94.58±0.54)%;播放单频音时,草鱼的反应次数、初次反应时间、平均反应时间、运动时间比均与对照组无显著差异(P>0.05)。本研究表明,5种复杂音(鱼游动声、引擎声、短吻鳄叫声、打桩声和游艇声)对草鱼幼鱼具有驱赶效果。本研究在丰富鱼类负趋音性研究的同时,为实际工程中声驱鱼辅助过鱼设施的设计和优化提供了科学依据。 展开更多
关键词 负趋音性 草鱼 声驱鱼技术 开放水域
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基于PID控制的小麦智能播种机研制与试验
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作者 张海军 郭呈成 +2 位作者 郭金山 孙福成 杨志平 《农业工程》 2024年第2期86-90,共5页
针对小麦播种机工作时地轮打滑和手动播量调整不精准等问题,研发了基于PID控制的小麦智能播种机。该播种机控制系统工作时,由速度传感器获取播种机行进速度,根据行进速度、单位面积播种量及播种机相关参数,计算排种轮转速的给定值,利用... 针对小麦播种机工作时地轮打滑和手动播量调整不精准等问题,研发了基于PID控制的小麦智能播种机。该播种机控制系统工作时,由速度传感器获取播种机行进速度,根据行进速度、单位面积播种量及播种机相关参数,计算排种轮转速的给定值,利用PID控制器实现对排种轮转速的控制。室内试验结果表明,播种机在不同作业条件下实际单位面积播种量与设定单位面积播种量误差均<2%,满足小麦精量播种的农艺要求。在中速和中高速作业条件下,智能排种系统控制精度较高、稳定性好。田间试验结果表明,小麦播种机的实际单位面积播种量与设定单位面积播种量之间最大误差2.33%,略大于室内试验结果,主要是由田间作业环境等因素造成的。基于PID控制的小麦智能精量播种机能有效提高播种精度。 展开更多
关键词 播种机 PID 小麦 精量播种 电驱动 田间试验
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可调式分土装置的设计及试验
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作者 邱祝川 潘永菲 王方艳 《农机化研究》 北大核心 2024年第9期180-185,共6页
针对垄作大葱收获分土阻力大问题,确定了可调式分土装置的结构,降低了分土作业时消耗的功率。装置由分土圆盘、支架、调节座等组成,可将葱垄两侧的土壤进行切割、抛送。借助Design-Expert8.0.6软件,以分土盘的距离、偏角、转速为试验因... 针对垄作大葱收获分土阻力大问题,确定了可调式分土装置的结构,降低了分土作业时消耗的功率。装置由分土圆盘、支架、调节座等组成,可将葱垄两侧的土壤进行切割、抛送。借助Design-Expert8.0.6软件,以分土盘的距离、偏角、转速为试验因素,功率为指标设计正交旋转组合试验,确定距离、偏角、转速对分土盘功率的影响顺序为偏角>转速>距离。利用响应曲面对试验结果进行优化,得到分土盘低功耗的最佳参数组合,即距离为100mm、偏角为20°、转速为30r/min。通过田间试验验证了最佳参数组合分土盘的分土效果较好,分土功率均值为145.8W。 展开更多
关键词 分土装置 调节装置 功耗 田间试验 大葱
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基于BioBERT与BiLSTM的临床试验纳排标准命名实体识别
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作者 李盛青 苏前敏 黄继汉 《中国医学物理学杂志》 CSCD 2024年第1期125-132,共8页
目的:提出一种基于BioBERT预训练模型的纳排标准命名实体识别方法(BioBERT-Att-BiLSTM-CRF),可自动提取临床试验相关信息,为高效制定纳排标准提供帮助。方法:结合UMLS医学语义网络和专家定义方式,制定医学实体标注规则,并建立命名实体... 目的:提出一种基于BioBERT预训练模型的纳排标准命名实体识别方法(BioBERT-Att-BiLSTM-CRF),可自动提取临床试验相关信息,为高效制定纳排标准提供帮助。方法:结合UMLS医学语义网络和专家定义方式,制定医学实体标注规则,并建立命名实体识别语料库以明确实体识别任务。BioBERT-Att-BiLSTM-CRF首先将文本转换为BioBERT向量并输入至双向长短期记忆网络以捕捉上下文语义特征;同时运用注意力机制来提取关键特征;最终采用条件随机场解码并输出最优标签序列。结果:BioBERT-Att-BiLSTM-CRF在纳排标准命名实体识别数据集上的效果优于其他基准模型。结论:使用BioBERT-Att-BiLSTM-CRF能更高效地提取临床试验的纳排标准相关信息,从而增强临床试验注册数据的科学性,并为临床试验纳排标准的制定提供帮助。 展开更多
关键词 纳排标准 命名实体识别 双向长短期记忆网络 条件随机场 临床试验
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不同比例芽孢杆菌对常见温室蔬菜病原菌抑制研究
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作者 安呈洁 张武 《现代农业研究》 2024年第7期94-97,共4页
本研究采用抑菌圈法探究不同比例芽孢杆菌对温室蔬菜病原菌的抑制效果,得到巨大芽孢杆菌、胶质芽孢杆菌与枯草芽孢杆菌的混合菌株对黄瓜白粉病、番茄灰霉病、茄子青枯病最佳的抑制比例,并在田间进行实验以验证最优方案。实验结果表明:... 本研究采用抑菌圈法探究不同比例芽孢杆菌对温室蔬菜病原菌的抑制效果,得到巨大芽孢杆菌、胶质芽孢杆菌与枯草芽孢杆菌的混合菌株对黄瓜白粉病、番茄灰霉病、茄子青枯病最佳的抑制比例,并在田间进行实验以验证最优方案。实验结果表明:芽孢杆菌的混合菌液对3种植物病原菌都具有明显的抑制作用,其中巨大芽孢杆菌、胶质芽孢杆菌、枯草芽孢杆菌比例为1∶1∶3的混合菌剂对黄瓜白粉病的抑制效果最明显,抑菌率达87.4%,田间防效达61.3%。混合比例为2∶1∶2的混合菌剂对番茄青枯病的抑制效果最明显,抑菌率达83.3%,田间防效达51.7%。混合比例为3∶2∶2的混合菌剂对茄子青枯病的抑制效果最明显,抑菌率达82.6%,田间防效达59.6%。结果表明混合菌剂对3种植物病原菌有良好的抑制效果,可应用于田间防治。 展开更多
关键词 芽孢杆菌 抑制 田间试验 抑菌圈法
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几种杀虫剂对稻纵卷叶螟的田间药效试验
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作者 何云凤 翁飚育 +3 位作者 马艳馨 喻枢玮 徐翔 王学贵 《农药科学与管理》 CAS 2024年第3期53-58,共6页
稻纵卷叶螟是水稻上一种重要的迁飞性害虫,对其防控的研究具有重要意义。为筛选出防效好的杀虫剂,在再生稻田开展了7种杀虫剂对稻纵卷叶螟的田间小区防控试验。结果表明,48%毒死蜱乳油、6%阿维·氯虫苯甲酰胺悬浮剂、15%茚虫威悬浮... 稻纵卷叶螟是水稻上一种重要的迁飞性害虫,对其防控的研究具有重要意义。为筛选出防效好的杀虫剂,在再生稻田开展了7种杀虫剂对稻纵卷叶螟的田间小区防控试验。结果表明,48%毒死蜱乳油、6%阿维·氯虫苯甲酰胺悬浮剂、15%茚虫威悬浮剂对稻纵卷叶螟速效性和持效性均较好,药后14 d防效仍能保持在>75%;20%氯虫苯甲酰胺悬浮剂和10%甲维·茚虫威悬浮剂防效略低,第14 d防效达分别达到71.59%和69.25%;而1.8%阿维菌素乳油和11.6%甲维·氯虫苯悬浮剂对稻纵卷叶螟防效最低,第14 d防效达仅达到64.63%和61.56%。综上,48%毒死蜱乳油、6%阿维·氯虫苯甲酰胺悬浮剂、15%茚虫威悬浮剂对稻纵卷叶螟具有较好的防治效果,可推荐防控稻纵卷叶螟。 展开更多
关键词 稻纵卷叶螟 田间药效试验 速效性 茚虫威
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水产养殖固体废弃物有机肥对土壤肥效和蔬菜品质的影响
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作者 丁兰 徐胜南 +3 位作者 周聃 刘梅 李万祈 邹松保 《中国农学通报》 2024年第19期102-108,共7页
研究旨在探讨水产养殖固体废弃物作为有机肥料对土壤肥力和蔬菜品质的影响。通过田间小区试验,设置4个不同处理组,分别为不施肥+辣椒(CK1)、不施肥+番茄(CK2)、施鱼粪有机肥+辣椒(T_(1))、施鸡粪有机肥+辣椒(T_(2))、施鱼粪有机肥+番茄(... 研究旨在探讨水产养殖固体废弃物作为有机肥料对土壤肥力和蔬菜品质的影响。通过田间小区试验,设置4个不同处理组,分别为不施肥+辣椒(CK1)、不施肥+番茄(CK2)、施鱼粪有机肥+辣椒(T_(1))、施鸡粪有机肥+辣椒(T_(2))、施鱼粪有机肥+番茄(T_(3))、施鸡粪有机肥+番茄(T_(4)),研究鱼粪有机肥施用对土壤肥力、辣椒和番茄生长及果实品质的影响。研究结果显示,与空白对照组相比,鱼粪有机肥可以显著增加土壤微生物数量,提高土壤有机质、全氮、全磷、有效磷、孔隙度等指标数值,从而增加土壤肥力,改善土壤物理结构,促进辣椒和番茄植株生长。同时鱼粪处理组蔬菜果实维生素C含量平均提高11.9%~24.0%、可溶性糖含量提高8.1%~16.7%,果实品质显著改善、营养价值提升。然而,与市售商品鸡粪有机肥相比,还需优化相关营养成分比例配置,尤其是提高速效钾含量。 展开更多
关键词 养殖池塘 固体废弃物 水产养殖固体废弃物 有机肥 土壤肥效 土壤肥力 蔬菜品质 鱼粪、鸡粪、田间试验
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Field Transmission of 100G and Beyond:Multiple Baud Rates and Mixed Line Rates Using Nyquist-WDM Technology 被引量:2
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作者 Zhensheng Jia Jianjun Yu +2 位作者 Hung-Chang Chien Ze Dong Di Huo 《ZTE Communications》 2012年第3期28-38,共11页
In this paper, we describe successful joint experiments with Deutsche Telecom on long-haul transmission of 100G and beyond over standard single mode fiber (SSMF) and with in-line EDFA-only amplification. The transmi... In this paper, we describe successful joint experiments with Deutsche Telecom on long-haul transmission of 100G and beyond over standard single mode fiber (SSMF) and with in-line EDFA-only amplification. The transmission link consists of 8 nodes and 950 km installed SSMF in DT' s optical infrastructure. Laboratory SSMF was added for extended optical reach. The first field experiment involved transmission of 8 x 216.8 Gbit/s Nyquist-WDM signals over 1750 km with 21.6 dB average loss per span. Each channel, modulated by a 54.2 Gbaud PDM-CSRZ-QPSK signal, is on a 50 GHz grid, which produces a net spectral efficiency (SE) of 4 bit/s/Hz. We also describe mixed-data-rate transmission coexisting with 1T, 400G, and 100G channels. The 400G channel uses four independent subcarriers modulated by 28 Gbaud PDM-QPSK signals. This yields a net SE of 4 bit/s/Hz, and 13 optically generated subcarriers from a single optical source are used in the 1T channel with 25 Gbaud PDM-QPSK modulation. The 100G signal uses real-time coherent PDM-QPSK transponder with 15% overhead of soft-decision forward-error correction (SD-FEC). The digital post filter and 1 -bit maximum-likelihood sequence estimation (MLSE) are introduced at the receiver DSP to suppress noise, linear crosstalk, and filtering effects. Our results show that future 400G and 1T channels that use Nyquist WDM can transmit over long-haul distances with higher SE and using the same QPSK format. 展开更多
关键词 coherent detection field trial coherent optical OFDM Nyquist WDM MLSE
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心律失常与起搏领域临床研究2023年度进展
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作者 吴寸草 李学斌 《中国介入心脏病学杂志》 CSCD 2024年第1期20-23,共4页
回顾2023年心律失常领域重要临床试验,涉及心房颤动(房颤)、起搏等方面。CIRDADOSE研究及EARLY-AF研究均肯定冷冻球囊消融治疗房颤疗效,减慢房颤进展。MANIFEST-PF研究回顾房颤脉冲场消融的成功率及安全性,在ADVENT研究中再次证实其安... 回顾2023年心律失常领域重要临床试验,涉及心房颤动(房颤)、起搏等方面。CIRDADOSE研究及EARLY-AF研究均肯定冷冻球囊消融治疗房颤疗效,减慢房颤进展。MANIFEST-PF研究回顾房颤脉冲场消融的成功率及安全性,在ADVENT研究中再次证实其安全性和有效性不劣于传统热消融。在左束支区域起搏(LBBAP)研究中,与双心室起搏(BVP)相比,LBBAP降低持续性室性心动过速(VT)/心室颤动(VF)和新发房颤发生率。对于起搏比例高且射血分数降低的起搏器或植入式心律转复除颤器(ICD)患者,BUDAPEST CRT升级研究肯定了其升级到心脏再同步除颤器(CRT-D)的明确获益。DANPACEⅡ研究显示窦房结功能障碍患者的心房起搏最小化并不能降低房颤的发生率。IDE研究显示Aveir DR双腔无导线起搏器术后3个月安全性良好,可提供可靠的心房起搏和房室同步。iSUSI研究是对皮下植入式心律转复除颤器的注册研究,发现心力衰竭和非心力衰竭患者不恰当和恰当电击率相似。 展开更多
关键词 临床试验 心房颤动 冷冻球囊消融 脉冲场消融 左束支区域起搏 CRT升级 无导线起搏器 植入式除颤器
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藜芦根茎提取物可溶液剂防治茶绿盲蝽田间药效试验
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作者 李志强 于志波 +3 位作者 张振葆 王本祥 曹秋华 段永春 《农药科学与管理》 CAS 2024年第1期48-52,共5页
为确定藜芦根茎提取物可溶液剂(藜芦胺)对防治茶绿盲蝽的效果,进行了不同浓度田间药效试验。结果表明,药后3 d,各处理防效和对照药剂防效均达最高值,0.5%藜芦根茎提取物可溶液剂600倍液处理的防效最高,为80.43%,各处理与0.3%苦参碱水剂... 为确定藜芦根茎提取物可溶液剂(藜芦胺)对防治茶绿盲蝽的效果,进行了不同浓度田间药效试验。结果表明,药后3 d,各处理防效和对照药剂防效均达最高值,0.5%藜芦根茎提取物可溶液剂600倍液处理的防效最高,为80.43%,各处理与0.3%苦参碱水剂无显著差异。本试验结果总体来看,0.5%藜芦根茎提取物可溶液剂防治茶绿盲蝽速效性、持效性相对较好,对茶园主要害虫茶小绿叶蝉也有较好的兼治作用;同时,对茶园主要益虫无明显不良影响。 展开更多
关键词 藜芦根茎提取物可溶液剂 绿盲蝽 田间药效试验
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基于大田试验的农田镉污染安全利用技术研究
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作者 李媛媛 冯先翠 +3 位作者 曹鹏 焦洪鹏 陈亚刚 江海燕 《环境科学与技术》 CAS CSCD 北大核心 2024年第3期154-161,共8页
文章针对珠三角乡镇工业区周边轻及轻微度镉污染农田土壤,分别开展了低累积水稻阻隔、钝化修复、植物阻隔联合钝化修复、超积累植物提取联合低累积作物间套种及轮作大田试验。结果表明:(1)在轻微度Cd污染土壤中直接种植低累积水稻金稻优... 文章针对珠三角乡镇工业区周边轻及轻微度镉污染农田土壤,分别开展了低累积水稻阻隔、钝化修复、植物阻隔联合钝化修复、超积累植物提取联合低累积作物间套种及轮作大田试验。结果表明:(1)在轻微度Cd污染土壤中直接种植低累积水稻金稻优998和长丝苗可实现安全生产;(2)土壤中分别添加4500 kg/hm^(2)的蒙脱复合调理剂、2640 kg/hm^(2)的改性蒙脱调理剂可使糙米中的Cd含量降低52.49%、62.50%,实现安全生产;(3)在轻度镉污染土壤上采用蒙脱复合调理剂联合种植金稻优998,可使糙米中的Cd含量降低68.61%,实现安全生产;(4)东南景天及其与玉米间套种处理一季对土壤中Cd提取率可分别达7.90%及7.22%,土壤中Cd分别降低11.5%及10.2%,且套种玉米可实现安全产出;东南景天修复间歇期,通过轮作低累积水稻金稻优998可实现不间断的安全生产。研究开发的土壤修复技术为轻及轻微度镉污染农田的安全利用提供了新的途径。 展开更多
关键词 土壤 修复 大田试验 安全利用
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7种杀虫剂对稻纵卷叶螟的田间防效比较
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作者 眭丹 管凌君 洪素娣 《现代农药》 CAS 2024年第3期90-92,共3页
采用田间小区试验,考察7种杀虫剂对稻纵卷叶螟的防治效果。试验结果表明:40%氰虫·甲虫肼SC 600 mL/hm^(2)处理对稻纵卷叶螟表现出良好的速效性和持效性,药后14 d的杀虫效果和保叶效果分别达到86.67%和86.25%,生产上有较大的推广应... 采用田间小区试验,考察7种杀虫剂对稻纵卷叶螟的防治效果。试验结果表明:40%氰虫·甲虫肼SC 600 mL/hm^(2)处理对稻纵卷叶螟表现出良好的速效性和持效性,药后14 d的杀虫效果和保叶效果分别达到86.67%和86.25%,生产上有较大的推广应用价值。25%乙基多杀菌素WG 150 g/hm^(2)和15%多杀·茚虫威SC 300 mL/hm^(2)处理防效也较好。 展开更多
关键词 杀虫剂 稻纵卷叶螟 田间试验 防治效果
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