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Effects of elevated CO_(2) concentration on CH_(4) and N_(2)O emissions from paddy fields:A meta-analysis

Science China Earth Sciences 2022年第1期65卷 96-106页

作者： Haiyang YU tianyu wang Qiong HUANG Kaifu SONG Guangbin ZHANG Jing MA Hua XU State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The inevitable rise of atmospheric CO_(2) concentration plays an important role in regulating the carbon(C)and nitrogen(N)cycling in the rice-cropping *** the effects of elevated CO_(2) concentration(ECO_(2))on CH_(4) and N_(2)O emissions from paddy fields is essential for evaluating agricultural production in response to global climate *** this study,we conducted a global meta-analysis to assess the overall effect of ECO_(2) on CH_(4) and N_(2)O emissions from paddy fields,aiming at providing a guideline for sustainable C and N management in paddy fields under future climate *** results showed that,overall,ECO_(2) significantly increased CH_(4) emissions from rice fields by 23%(P10 yr)of ECO_(2) ,ECO_(2) significantly reduced CH_(4) and N_(2)O emissions from paddy fields by 27%and 53%,respectively(P<0.05).Along with the increasing levels of ECO_(2) ,the stimulating effect of ECO_(2) on CH_(4) emissions showed a trend of"weakening firstly and then strengthening",while its effect on N_(2)O emissions changed from stimulation to *** managements(e.g.,N application rates,straw incorporations,water regimes,and rice cultivars)affected the effects of ECO_(2) on CH_(4) and N_(2)O emissions from paddy *** no or half amount of straw incorporation,ECO_(2) increased CH_(4) emissions by 27% or 49%(P<0.05)from paddy fields,respectively,while non-significant effects on CH_(4) emissions from paddy fields were observed under full straw *** the increasing amount of straw incorporation,the reductions in N_(2)O emissions from paddy fields were enhanced by ECO_(2).Compared with a continuous flooding regime,intermittent irrigation weakened the promoted effect on CH_(4) emissions but stimulated the inhibited effect on N_(2)O emissions from paddy fields under ECO_(2).Therefore,under the future condition of ECO_(2),it is recommended to adopt the appr

关键词： Elevated CO_(2) Paddy field CH_(4) N_(2)O Agronomy managements Meta-analysis

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Discrete particle modeling of granular temperature distribution in a bubbling fluidized bed

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Particuology 2012年第4期10卷 428-437页

作者： Yurong He tianyu wang Niels Deen Martin van Sint Annaland Hans Kuipers Dongsheng Wen Department of Power Engineering College of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Department of Chemical Engineering and Chemistry Eindhoven University of TechnologyPO Box 5135600 MB EindhovenThe Netherlands School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon El 4NSUK

The discrete hard sphere particle model （DPM） is applied in this work to study numerically the distribu- tions of particle and bubble granular temperatures in a bubbling fluidized bed. The dimensions of the bed and other parameters are set to correspond to those of Miuller et al（2008）. Various drag models and oper- ational parameters are investigated to find their influence on particle and bubble granular temperatures. Various inlet superficial gas velocities are used in this work to obtain their effect on flow characteristics. It is found that the superficial gas velocity has the most important effect on granular temperatures including bubble granular temperature, particle translational granular temperature and particle rotational granular temperature. The drag force model affects more seriously the large scale variables such as the bubble gran- ular temperature. Restitution coefficient influences all granular temperatures to some degree. Simulation results are compared with experimental results by Muller et al. （2008） showing reasonable agreement.

关键词： Bubbling fluidized bedDiscrete hard sphere modelParticle and bubble granular temperature

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鄂尔多斯盆地页岩油储层前置CO_(2)压裂流体分布特征

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西安石油大学学报（自然科学版） 2024年第2期39卷 55-61页

作者：臧雨溪王海柱王斌孙居正王天宇田港华石明亮吴毓乾田守嶒中国石油大学(北京)油气资源与探测国家重点实验室中国北京102249 中国石油新疆油田分公司采气一厂新疆克拉玛依834000 中国石油大学(北京)克拉玛依校区石油学院新疆克拉玛依834000

以鄂尔多斯盆地页岩油储层为对象,基于油藏数值模拟软件CMG-GEM及GOHFER,研究了CO_(2)注入量、闷井时间、储层水平/垂直渗透率比值、双水平井射孔压裂方式对流体分布的影响。结果表明:水平和垂直方向渗透率的差异性导致CO_(2)在水平方... 详细信息

以鄂尔多斯盆地页岩油储层为对象,基于油藏数值模拟软件CMG-GEM及GOHFER,研究了CO_(2)注入量、闷井时间、储层水平/垂直渗透率比值、双水平井射孔压裂方式对流体分布的影响。结果表明:水平和垂直方向渗透率的差异性导致CO_(2)在水平方向波及范围较大,注入量对波及长度影响更为敏感,该研究条件下注入量为140 m^(3)时邻段水平波及范围出现交汇,可认定为最优注入量;延长闷井时间可增大CO_(2)波及范围,但注入量的影响程度更大,建议通过调节注入量来控制波及范围;水平/垂直渗透率比对CO_(2)波及范围影响较大,比值越大水平方向波及越广、垂向波及范围越窄,呈扁平状分布;对比双水平井拉链式与同步式射孔压裂,其中拉链式射孔压裂有助于提升CO_(2)波及范围,有利于油气开发。研究可为页岩油储层前置CO_(2)压裂工艺参数优化设计提供理论指导。

关键词：储层改造前置CO_(2)注入流体分布非常规油气页岩油储层

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Polymorphism of LiCdBO_(3):Crystal structures,phase transitions and optical characterizations

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Chinese Journal of Structural Chemistry 2023年第1期42卷 5-8页

作者： Qingxiong Liu Qian Wu tianyu wang Lei Kang Zheshuai Lin Yonggang wang Mingjun Xia Beijing Center for Crystal Research and Development Key Laboratory of Functional Crystals and Laser TechnologyTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing100190China School of Materials Science and Engineering Peking UniversityBeijing 100871China School of Future Technology University of Chinese Academy of SciencesBeijing100049China

*** Inorganic borate crystals have received considerable attention in many applications as nonlinear optical(NLO)crystals,birefringence crystals and scintillator materials[1-3].Recently,it is a well-known strategy for... 详细信息

关键词： transitions utilizing designing

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向阳水库防洪分析及汛限水位确定研究

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水利规划与设计 2024年第10期 33-37页

作者：王天宇赵惠萍吴泽宇长江勘测规划设计研究有限责任公司湖北武汉430010

汛限水位直接影响水库的防洪安全和兴利效益。文章以向阳水库坝址下游防洪控制断面的河道安全泄量为边界条件,选取以水库坝址为主、坝址至防洪控制断面区间相应的设计洪水地区组成,采取固定泄量防洪调度方式确定了水库的防洪库容;从移... 详细信息

汛限水位直接影响水库的防洪安全和兴利效益。文章以向阳水库坝址下游防洪控制断面的河道安全泄量为边界条件,选取以水库坝址为主、坝址至防洪控制断面区间相应的设计洪水地区组成,采取固定泄量防洪调度方式确定了水库的防洪库容;从移民征地、工程效益、工程投资等方面对防洪库容与兴利库容完全结合、部分结合两种布置方式进行了比选分析。结果表明水库采用防洪库容与兴利库容部分结合的布置方式较优,相关分析论证方法可为其他综合利用水库汛限水位的确定提供工程实践参考。

关键词：防洪控制断面防洪库容与兴利库容部分结合汛限水位向阳水库

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基于振动信号变化的轨道交通设备状态监测系统

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自动化与仪器仪表 2024年第1期 7-11页

作者：王天予陈雪静梁修惠重庆交通大学交通运输学院重庆402260 四川轻化工大学数学与统计学院四川自贡643002 重庆航天职业技术学院重庆400000

针对轨道交通设备运行环境复杂,部分异常设备状态无法精准监测的问题,设计基于振动信号变化的轨道交通设备状态监测系统。系统的振动信号采集模块,选取型号为CA-YD-3193的压电式振动加速度传感器,采集轨道交通设备振动信号,采集的振动... 详细信息

针对轨道交通设备运行环境复杂,部分异常设备状态无法精准监测的问题,设计基于振动信号变化的轨道交通设备状态监测系统。系统的振动信号采集模块,选取型号为CA-YD-3193的压电式振动加速度传感器,采集轨道交通设备振动信号,采集的振动信号利用轨道交通车载监控网络传送至监测服务终端。监测服务终端选取Hilbert变换方法变换处理振动信号,提取设备状态特征。利用设备状态特征提取结果构建样本集,利用样本集内样本构建二叉树,组成孤立森林,利用孤立森林算法输出轨道交通设备状态监测结果。系统测试结果表明,该系统可以依据设备振动信号变化,监测信号设备、轨道设备、消防设备等轨道交通设备状态,适用于轨道交通设备运维的实际应用中。

关键词：振动信号变化轨道交通设备状态监测系统 Hilbert变换孤立森林

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TiC添加对A356铝合金组织与力学性能的影响研究

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热加工工艺 2024年第18期53卷 60-64,68页

作者：王晓宇贾金浩马世卿王天宇刘洋李伯超蔡政王春晓兰紫光石家庄铁道大学材料科学与工程学院河北石家庄050043 石家庄铁道大学交通工程与环境协同发展新材料重点实验室河北石家庄050043

采用搅拌熔铸法,制备了组织结构均匀的TiC/A356铝合金,研究了TiC含量对A356铝合金的物相组成、微观组织和力学性能的影响规律。结果表明,随着TiC含量的增加,TiC/A356铝合金的拉伸强度和伸长率呈先上升后降低的规律,维氏硬度则持续上升。... 详细信息

采用搅拌熔铸法,制备了组织结构均匀的TiC/A356铝合金,研究了TiC含量对A356铝合金的物相组成、微观组织和力学性能的影响规律。结果表明,随着TiC含量的增加,TiC/A356铝合金的拉伸强度和伸长率呈先上升后降低的规律,维氏硬度则持续上升。当TiC含量为3wt%时,合金的综合性能最佳,其极限抗拉强度为197.1 MPa、伸长率为9.10%、维氏硬度为84.7 HV。此外,还分析了TiC复合强化A356合金的作用机理模型。

关键词： TiC A356铝合金微观组织力学性能强化机理

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Latitudinal and interannual variations of the spring phytoplankton bloom peak in the East Asian marginal seas

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Acta Oceanologica Sinica 2016年第12期35卷 81-88页

作者： CHEN Cheng MAO Zhihua HAN Guoqi ZHU Qiankun GONG Fang wang tianyu State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration Biological and Physical Oceanography Section Fisheries and Oceans CanadaNorthwest Atlantic Fisheries CentreNewfoundland and Labrador

Combined studies of latitudinal and interannual variations of annual phytoplankton bloom peak in East Asian marginal seas(17°–58°N, including the northern South China Sea(SCS), Kuroshio waters, the Sea of Japan and the Okhotsk Sea) are rarely. Based on satellite-retrieved ten-year(2003–2012) median timing of the annual Chlorophyll a concentration(Chl a) climax, here we report that this annual spring bloom peak generally delays from the SCS in January to the Okhotsk Sea in June at a rate of(21.20±2.86) km/d(decadal median±SD). Spring bloom is dominant feature of the phytoplankton annual cycle over these regions, except for the SCS which features winter bloom. The fluctuation of the annual peak timing is mainly within ±48 d departured from the decadal median peak date, therefore this period(the decadal median peak date ±48 d) is defined as annual spring bloom period. As sea surface temperature rises, earlier spring bloom peak timing but decreasing averaged Chl a biomass in the spring bloom period due to insufficient light is evident in the Okhotsk Sea from 2003 to 2012. For the rest of three study domains, there are no significant interannual variance trend of the peak timing and the averaged Chl a biomass. Furthermore this change of spring phytoplankton bloom timing and magnitude in the Okhotsk Sea challenges previous prediction that ocean warming would enhance algal productivity at high latitudes.

关键词： latitudinal and interannual variation spring bloom peak phytoplankton phenology East Asian marginal seas climate change

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Identification of a Printed Anti-Counterfeiting Code Based on Feature Guidance Double Pool Attention Networks

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Computers, Materials & Continua 2023年第5期75卷 3431-3452页

作者： Changhui You Hong Zheng Zhongyuan Guo tianyu wang Jianping Ju Xi Li School of Cyber Science and Engineering Wuhan UniversityWuhan430000China School of Electronic Information Wuhan UniversityWuhan430000China College of Artificial Intelligence Nanchang Institute of Science and TechnologyNanchang330108China

The authenticity identification of anti-counterfeiting codes based on mobile phone platforms is affected by lighting environment,photographing habits,camera resolution and other factors,resulting in poor collection quality of anti-counterfeiting codes and weak differentiation of anti-counterfeiting codes for high-quality *** an anticounterfeiting code authentication algorithm based on mobile phones is of great commercial *** the existing algorithms developed based on special equipment can effectively identify forged anti-counterfeiting codes,the anti-counterfeiting code identification scheme based on mobile phones is still in its *** address the small differences in texture features,low response speed and excessively large deep learning models used in mobile phone anti-counterfeiting and identification scenarios,we propose a feature-guided double pool attention network(FG-DPANet)to solve the reprinting forgery problem of printing anti-counterfeiting *** address the slight differences in texture features in high-quality reprinted anti-counterfeiting codes,we propose a feature guidance algorithm that creatively combines the texture features and the inherent noise feature of the scanner and printer introduced in the reprinting process to identify anti-counterfeiting code *** introduction of noise features effectively makes up for the small texture difference of high-quality anti-counterfeiting *** double pool attention network(DPANet)is a lightweight double pool attention residual *** the condition of ensuring detection accuracy,DPANet can simplify the network structure as much as possible,improve the network reasoning speed,and run better on mobile devices with low computing *** conducted a series of experiments to evaluate the FG-DPANet proposed in this *** results show that the proposed FG-DPANet can resist highquality and small-size anti-counterfeiting code reprint forgery.B

关键词： Deep learning digital image anti-counterfeiting feature guidance image processing reprint forgery

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具有全重联功能的TCMS系统方案论述

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铁道车辆 2024年第4期62卷 77-81页

作者：张晓雨王天宇郝宏峰中车大连机车车辆有限公司辽宁大连116022

城市轨道交通线路客流量的特征具有不同运营阶段或全天内不同时段以及不同区段差异较大等特点,传统的固定编组运营模式无法很好地解决运力、客流、能耗匹配的问题。根据城市轨道交通在不同区段、时段下的客流特征,在保证较高列车服务水... 详细信息

城市轨道交通线路客流量的特征具有不同运营阶段或全天内不同时段以及不同区段差异较大等特点,传统的固定编组运营模式无法很好地解决运力、客流、能耗匹配的问题。根据城市轨道交通在不同区段、时段下的客流特征,在保证较高列车服务水平的条件下,通过绞线式列车总线(Wire Train Bus,WTB)架构以及列车之间全重联,使得头车可以控制后面与其重联的列车,达到所有列车控制指令完全一致性,最终达到灵活改变列车编组长度来实现运力与客流需求动态匹配,合理优化各时段列车满载率,有效解决动力浪费或服务水平低下的问题。

关键词：城市轨道交通 TCMS 全重联 WTB架构客流特征灵活编组

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