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有机鲜食玉米规范化种植及发展思考

种业导刊 2024年第2期 3-6页

作者：赵品范磊燕照玲韩启忠苏磊李建林郑州市农业技术推广中心河南郑州450011 河南省农业科学院河南郑州450002

为推广有机鲜食玉米规范化种植,提升优质、安全、健康鲜食玉米的供应能力,从种植区域选择、种子选择、翻耕整地、播种、施肥、田间管理、病虫害防治、收获加工等系列工序方面详细总结了有机鲜食玉米的规范化栽培技术,并从规范化种植、... 详细信息

为推广有机鲜食玉米规范化种植,提升优质、安全、健康鲜食玉米的供应能力,从种植区域选择、种子选择、翻耕整地、播种、施肥、田间管理、病虫害防治、收获加工等系列工序方面详细总结了有机鲜食玉米的规范化栽培技术,并从规范化种植、管理、施肥、用药,推动鲜食玉米品种培优、品质提升、品牌打造和标准化生产建设,注重有机认证、建立质量可回溯体系、打造区域特色品牌等方面对有机鲜食玉米规范化发展提出了建议,以期因地制宜发展以质优、安全、绿色、有机为核心的鲜食玉米产业,推动优质农业发展,改善农村生态环境,提高农业农村收入,促进乡村振兴。

关键词：有机作物鲜食玉米规范化种植栽培技术发展

Earth Rotation Parameters Determination with BDS-3/LEO Simulations under Small-scale Ground Networks

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Earth Rotation Parameters Determination with BDS-3/LEO Simul...

Properties of Belite-Rich Portland Cement and Concrete in China

第十三届中国卫星导航年会

作者： Xinqi fang lei fan Shiwei Guo Linghao Zhou Chuang Shi School of Electronics and Information Engineering Beihang University Key Laboratory of Navigation and Communication Fusion Technology Ministry of Industry and Information Technology Research Institute for Frontier Science Beihang University

The inclusion of Low Earth Orbit（LEO） spaceborne GNSS observation or Inter-Satellite Link（ISL） measurement improves strength of normal equation, and then helps to improve ERP accuracy. With a 15-day simulation of BDS-3 ISL measurements and BDS-3 observations from 72 LEO satellites, 10 global stations and 10 Chinese stations, this work studies the impact of LEO satellites and BDS-3 ISL on ERP accuracy. Results show that the introduction of LEO satellites and BDS-3 ISL significantly improves ERP accuracy. Taking the IERS 14 C04 product as a reference, with ground network of 10 global stations, the RMS of polar X, Y coordinate and LOD after introducing 72 LEO satellites are 10.4μas, 10.8μas, 3.9μs, respectively. Compared with ERP accuracy based on solely 10 global stations, the improvement reaches 66.8%, 74.0%, 62.1%, respectively. The accuracy is equivalent to that of using 115 global stations, and the polar coordinate accuracy is better than the case of introducing BDS-3 ISL. Based on 10 Chinese stations, the RMS of polar X, Y coordinate and LOD with BDS-3 ISL are 16.3μas, 39.8μas, 7.9μs, respectively. The contribution of BDS-3 ISL is more pronounced than that of 72 LEO satellites. ERP results based on Chinese stations indicate that the polar Y coordinate accuracy is always worse than the X component, which is not found in results of global stations. Furthermore, analysis of correlation indicates that the inclusion of LEO satellites or BDS-3 ISL reduces correlation between estimated parameters.

关键词： Earth Rotation Parameters（ERP） Low Earth Orbit（LEO） satellite Inter-Satellite Link（ISL） Integrated adjustment

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Journal of Civil Engineering and Architecture 2015年第4期9卷 384-392页

作者： Tongbo Sui lei fan Zhaijun Wen Jing Wang Sinoma Research Institute Sinoma International Engineering Co. Ltd Beijing 100102 China Research Institute of Cement and New Building Materials China Building Materials Academy Beijing 100024 China

Performances of belite-rich Portland cement, or HBC (high belite cement), and the resultant concrete are introduced by comparing with that of alite based PC (Portland cement) and concrete. The comparison study of cement properties indicates that HBC possesses the properties of less water demand for normal consistency, better compatibility with water reducer, higher later age strength after 28-day under standard curing temperature of 20 °C, unique strength gain under elevated curing temperatures of 38~70 °C, lower hydration heat evolution and temperature rise, lower drying shrinkage and excellent resistance to sulphate attack. These results have been demonstrated by the comparison performance evaluation of concretes prepared by HBC and PC in terms of workability, physical mechanical properties and durability when making high performance high strength concrete and massive concrete.

关键词：高强度混凝土高贝利特水泥硅酸盐水泥波特兰水泥中国水泥性能抗硫酸盐侵蚀物理机械性能

全髋关节置换前人工智能(AI)规划的作用与意义

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中国组织工程研究 2024年第9期28卷 1372-1377页

作者：闵美鹏吴进 URBA RAFI 张文杰高嘉王云华何斌范磊南京医科大学第二附属医院骨科江苏省南京市210011

背景:传统X射线胶片术前规划常常不准确,会导致一些术中和术后并发症,增加了手术时间和术中出血量,一定程度影响了全髋关节置换的手术效果。目的:研究人工智能(AI)术前规划在全髋关节置换术中的准确性和应用效果。方法:选取患侧初次行... 详细信息

背景:传统X射线胶片术前规划常常不准确,会导致一些术中和术后并发症,增加了手术时间和术中出血量,一定程度影响了全髋关节置换的手术效果。目的:研究人工智能(AI)术前规划在全髋关节置换术中的准确性和应用效果。方法:选取患侧初次行全髋关节置换的患者60例,其中30例应用人工智能(AI)三维术前规划为试验组、30例应用传统X射线胶片二维术前规划为对照组,两组患者的性别、年龄、病情等一般资料比较,差异均无统计学意义(P>0.05)。比较两组患者术中实际安放假体与术前规划假体匹配情况、术中手术时间、术中出血量、术后即刻双侧股骨偏心距差值、双侧联合偏心距差值及双下肢长度差值和术后3个月Harris评分,分析两种术前规划的准确性和应用效果。结果与结论:①两组患者均获得术后4-6个月的随访,其中对照组有1例患者于术后5 d发生假体后脱位,行手法复位后恢复,无再次脱出,其余患者均未出现术后并发症及术后死亡;②髋臼侧、股骨侧假体完全匹配率:试验组明显优于对照组(P0.05);⑤试验组患者术后3个月Harris评分明显高于对照组患者(P<0.05);⑥结果说明,人工智能(AI)术前规划相较于传统胶片规划,更能准确预测假体型号、缩短手术时间、减少术中出血量、减少术后双下肢不等长发生、加快术后康复。

关键词：人工智能(AI) 全髋关节置换术术前规划模板测量假体

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地下水封洞库帷幕灌浆试验与渗控效果分析

隧道与地下工程灾害防治 2024年第1期6卷 64-72页

作者：丁长栋张宜虎李领罗荣范雷丁祥曹磊长江科学院水利部岩土力学与工程重点实验室中国安能集团第一工程局有限公司湖北工业大学土木建筑与环境学院

以某地下水封洞库为背景，针对工程区内导水构造发育引起的洞室渗涌水问题，引入帷幕灌浆技术进行封堵，并通过现场试验和数值模拟等手段研究帷幕灌浆对岩体渗透性的影响规律及其在洞库工程中的渗控效果。结果表明：帷幕灌浆分序实施过... 详细信息

以某地下水封洞库为背景，针对工程区内导水构造发育引起的洞室渗涌水问题，引入帷幕灌浆技术进行封堵，并通过现场试验和数值模拟等手段研究帷幕灌浆对岩体渗透性的影响规律及其在洞库工程中的渗控效果。结果表明：帷幕灌浆分序实施过程中，经Ⅰ序孔灌浆后，Ⅱ序孔部位岩体的渗透性减弱，灌前透水率和单位耗灰量的分序递减规律较好。岩体渗透性较大时，其可灌性好、耗灰量大，在Ⅱ序孔灌浆时透水率和单位耗灰量降低明显，岩体降渗效果较显著。帷幕灌浆Ⅰ序孔的灌前透水率与灌浆孔段埋深有关，在爆破影响范围以外，应适当提高灌浆压力，增大耗灰量，达到更好的灌浆效果。渗流场分析揭示防渗帷幕对于降低灌浆范围内导水构造的渗透性具有积极作用，可以部分截断天然地下水沿主要导水构造向洞室内渗漏，在一定程度上控制洞室整体渗水量。

关键词：地下水封洞库帷幕灌浆渗流场控制导水构造渗控效果

Morphologies of intermetallic compound phases in Sn-Cu and Sn-Co peritectic alloys during directional solidification

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China Foundry 2022年第5期19卷 411-418页

作者： Peng Peng Jin-mian Yue An-qiao Zhang Jia-tai Wang Jiang-lei fan School of Physics and Electronic Information Engineering Qinghai Normal UniversityXining 753000China School of Materials and Energy Lanzhou UniversityLanzhou 730000China Northwest Rare Metal Materials Research Institute Shizuishan 753099NingxiaChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan 030003China School of Mechanical and Electrical Engineering Zhengzhou University of Light IndustryZhengzhou 450000China

The morphologies of intermetallic phases(IMCs)during directional solidification of the Sn-Cu(L+Cu_(3)Sn→Cu_(6)Sn_(5))and Sn-Co(L+CoSn→CoSn_(2))peritectic systems were analyzed.The primary Cu_(3)Sn and peritectic Cu_(6)Sn_(5)phases in Sn-Cu alloy are IMCs whose solubility ranges are narrow,while both the primary CoSn and peritectic CoSn_(2)phases in Sn-Co alloy are IMCs whose solubility ranges are nil in equilibrium condition.The experimental results before acid corrosion shows that the dendritic morphology of both the Cu_(6)Sn_(5)and CoSn_(2)phases can be observed.The investigation on the local dendritic morphology after deep acid corrosion shows that these dendrites are composed of small sub-structures with faceted feature.Faceted growth of the primary Cu_(3)Sn and CoSn phases is also confirmed,and a faceted to non-faceted transition in their morphologies is observed with increasing growth velocities.Further analysis shows that the dendritic morphology is formed in the solidified phases whose solubility range is larger during peritectic solidification.

关键词： intermetallic compound phase peritectic alloy directional solidification solubility range sub-structure

COX1基因多态性与血小板聚集功能在缺血性脑卒中复发患者中的交互作用

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中风与神经疾病杂志 2024年第6期41卷 555-559页

作者：刘星亮范磊娄展宋征宇河北北方学院附属第一医院神经内科河北张家口075000

目的探讨COX1基因多态性与血小板聚集功能的交互作用对缺血性脑卒中复发患者的影响。方法选择2020年7月—2023年7月缺血性脑卒中复发患者70例为观察组,另选择同期体检的70例健康者为对照组。比较两组的一般资料并分析COX1基因多态性... 详细信息

目的探讨COX1基因多态性与血小板聚集功能的交互作用对缺血性脑卒中复发患者的影响。方法选择2020年7月—2023年7月缺血性脑卒中复发患者70例为观察组,另选择同期体检的70例健康者为对照组。比较两组的一般资料并分析COX1基因多态性。检测并比较两组患者COX1基因多态性位点基因型及等位基因频率分布。比较观察组不同基因型血小板聚集率水平及与缺血性脑卒中复发易感性的关系及交互作用。结果两组的血小板计数、COX1、血小板聚集率差异具有统计学意义(P基因型CT患者>基因型TT患者(P<0.05),差异具有统计学意义。COX1(rs1330344位点)基因型与患者血小板聚集率显著相关。糖尿病史、高血压史、TG、HCY、COX1(rs1330344位点)基因型、血小板聚集率均为缺血性脑卒中复发的独立危险因素(P<0.05)。COX1(rs1330344位点)基因型CC与血小板聚集率在患者缺血性脑卒中复发易感性中呈正向交互作用(3.266<1.736×2.114,为次相乘模型)。结论 COX1(rs1330344位点)基因型CC和血小板聚集率在患者缺血性脑卒中复发易感性中呈正向交互作用且易感性显著增加,临床上可据此制定早期预防措施。

关键词： COX1 基因多态性血小板聚集缺血性脑卒中复发

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Defence Technology(防务技术) 2023年第9期27卷 138-153页

作者： Zeng Liu Cheng-lei fan Chun-li Yang Zhu Ming San-bao Lin Lang-ping Wang State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China Inner Mongolia Metal Material Research Institute Yantai264000China

Ar-N_(2)-O_(2)ternary shielding gas is employed in dissimilar welding between high nitrogen steel and low alloy steel.The effect of O_(2)and N_(2)is investigated based on the systematical analysis of the metal transfer,nitrogen escape phenomenon,weld appearance,nondestructive detection,nitrogen content distribution,microstructure and mechanical properties.There are two nitrogen sources of the nitrogen in the weld:high nitrogen base material and shielding gas.The effect of shielding gas is mainly reflected in these two aspects.The change of the droplet transfer mode affects the fusion ratio,N2in the shielding gas can increase nitrogen content and promote the nitrogen uniform distribution.The addition of 2%O_(2)to Ar matrix can change the metal transfer from globular transfer to spray transfer,high nitrogen base material is thereby dissolved more to the molten pool,making nitrogen content increase,ferrite decrease and the mechanical properties improve.When applying N2-containing shielding gas,arc stability becomes poor and short-circuiting transfer frequency increases due to the nitrogen escape from droplets and the molten pool.Performance of the joints is improved with N_(2)increasing,but internal gas pores are easier to appear because of the poor capacity of low alloy steel to dissolve nitrogen,The generation of pores will greatly reduce the impact resistance.4-8%N2content in shielding gas is recommended in this study considering the integrated properties of the dissimilar welded joint.

关键词： High nitrogen steel Dissimilar steel joints Shielding gas Metal transfer Microstructure Mechanical properties

Fast spreading of surface ozone in both temporal and spatial scale in Pearl River Delta

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Journal of Environmental Sciences 2024年第3期137卷 540-552页

作者： Tianhui Cao Haichao Wang lei Li Xiao Lu Yiming Liu Shaojia fan School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China

Surface ozone(O_(3))is a major air pollutant and draw increasing attention in the Pearl River Delta(PRD),China.Here,we characterize the spatial-temporal variability of ozone based on a dataset obtained from 57 national monitoring sites during 2013-2019.Our results show that:(1)the seasonal difference of ozone distribution in the inland and coastal areas was significant,which was largely affected by the wind pattern reversals related to the East Asian monsoon,and local ozone production and destruction;(2)the daily maximum 8hr average(MDA8 O_(3))showed an overall upward trend by 1.11 ppbv/year.While the trends in the nine cities varied differently by ranging from-0.12 to 2.51 ppbv/year.The hot spots of ozone were spreading to southwestern areas from the central areas since 2016.And ozone is becoming a year-round air pollution problem with the pollution season extending to winter and spring in PRD region.(3)at the central and southwestern PRD cities,the percentage of exceedance days from the continuous type(defined as≥3 days)was increasing.Furthermore,the ozone concentration of continuous type was much higher than that of scattered exceedance type(<3 days).In addition,although the occurrence of continuous type starts to decline since2017,the total number of exceedance days during the continuous type is increasing.These results indicate that it is more difficult to eliminate the continuous exceedance than the scatter pollution days and highlight the great challenge in mitigation of O_(3)pollution in these cities.

关键词： Surface ozone pollution Ozone trend Spatial and temporal variability Pearl River Delta Pollution mitigation