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海冰动力过程的改进离散元模型及在渤海的应用

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海洋学报 2015年第5期37卷 54-67页

作者：季顺迎王安良米丽丽刘煜李宝辉大连理工大学工业装备结构分析国家重点实验室辽宁大连116023 国家海洋环境预报中心国家海洋局海洋灾害预报技术研究重点实验室北京100081

海冰的断裂、重叠和堆积等离散分布特性广泛地存在于极区和副极区的不同海域,并对海冰的生消、运移过程有着重要影响。针对海冰在不同尺度下的离散分布特点,发展海冰动力过程的离散元方法有助于完善海冰数值模式,提高海冰数值模拟的计... 详细信息

海冰的断裂、重叠和堆积等离散分布特性广泛地存在于极区和副极区的不同海域,并对海冰的生消、运移过程有着重要影响。针对海冰在不同尺度下的离散分布特点,发展海冰动力过程的离散元方法有助于完善海冰数值模式,提高海冰数值模拟的计算精度。为此,本文针对海冰生消运移过程中的非连续分布和形变特性,发展了适用于海冰动力过程的改进离散元模型(MDEM)。不同于传统离散元方法,该模型将海冰离散为具有一定厚度、尺寸和密集度的圆盘单元。海冰单元设为诸多浮冰块的集合体,其在运移和相互接触碰撞过程中,依照质量守恒发生单元尺寸、密集度和厚度的相应变化。基于海冰离散性和流变性的特点,该模型采用黏弹性接触本构模型计算单元间的作用力,并依据Mohr-Coulomb准则计算海冰法向作用下的塑性变形及切向摩擦力。为验证该模型的可靠性,本文对海冰在规则水域内的运移和堆积过程进行了分析,离散元计算结果与解析值相一致;此外,对旋转风场下海冰漂移规律的模拟进一步验证了本文方法的精确性。在此基础上,对渤海辽东湾的海冰动力过程进行了48h数值分析,计算结果与卫星遥感资料和油气作业区的海冰现场监测数据吻合良好。在下一步工作中将考虑海冰离散元模拟中的热力因素影响,发展具有冻结、断裂效应的海冰离散元模型,更精确地模拟海冰动力-热力耦合作用下的生消和运移过程。

关键词：海冰动力学离散元模型堆积冰渤海

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生态活性有机肥在蔬菜及果树上的施用效果

中国农学通报 2006年第10期22卷 221-224页

作者：张丽娟王淑珍李鑫李玉敏李保会河北农业大学资源环境科学学院保定071000 河北清苑县农业局清苑071100 河北农业大学科技管理处保定071001

在蔬菜及果树上进行了施用活性有机肥的试验,结果表明:(1)施用活性有机肥对大白菜生长发育有较好的促进作用。株高、叶片数、叶宽、开展度3次测量均高于常规施肥,产量比常规施肥每公顷增产5010kg,增产率达10.96%,投入产出比也较高,效益... 详细信息

在蔬菜及果树上进行了施用活性有机肥的试验,结果表明:(1)施用活性有机肥对大白菜生长发育有较好的促进作用。株高、叶片数、叶宽、开展度3次测量均高于常规施肥,产量比常规施肥每公顷增产5010kg,增产率达10.96%,投入产出比也较高,效益比为1:6;植株的抗病能力也较常规施肥(5.6%)强,降低了2.9%。(2)活性有机肥较传统施肥明显提高番茄的品质。座果总数增加14,小果数量降低4%,大果和中等果数分别增加2%和1.9%;果实可溶性固形物含量较传统施肥高3.1%。(3)施用活性有机肥处理能提高李果百果重、单株平均产量,分别比施等量普通复合肥的高11.1%和22.7%;施用活性有机肥可显著降低李果果实的总酸度,降低了0.1%,Vc含量和可溶性固形物含量分别提高0.2mg/100g和2.1%,果实硬度指标未表现出差异。

关键词：活性有机肥增产效果大白菜番茄大石早生李

基于希尔伯特变换的风电机组齿轮箱故障诊断方法研究

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机床与液压 2024年第9期52卷 215-220页

作者：高宏伟李新成何晓宁刘长安王瀚驰李文成张宝慧青岛农业大学机电工程学院山东青岛266109 华能新能源股份有限公司山西分公司山西太原030002

齿轮箱作为风电机组关键部件,由于运行环境以及工况的复杂性,易出现故障,严重威胁机组安全稳定运行。因此,对齿轮箱进行故障诊断对确保风电机组稳定运行具有重要意义。在介绍齿轮箱结构特点、故障模式、振动监测的基础上,结合齿轮箱结... 详细信息

齿轮箱作为风电机组关键部件,由于运行环境以及工况的复杂性,易出现故障,严重威胁机组安全稳定运行。因此,对齿轮箱进行故障诊断对确保风电机组稳定运行具有重要意义。在介绍齿轮箱结构特点、故障模式、振动监测的基础上,结合齿轮箱结构特点,给出齿轮与轴承故障特征频率的计算方法。同时采用希尔伯特变换与倒谱分析相结合的方法对齿轮箱振动数据进行分析,提取故障特征频率。经实例验证,该方法能够准确得到齿轮箱故障频率的同时定位齿轮箱故障,实现风电机组齿轮箱的故障诊断。

关键词：齿轮箱风电机组故障诊断振动监测

特高压换流变压器含水系灭火剂的水喷雾系统灭火试验研究

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湖南电力 2024年第2期44卷 44-49页

作者：陈宝辉吴传平周天念刘毓李波国网湖南省电力有限公司防灾减灾中心(电网防灾减灾全国重点实验室) 湖南长沙410129 湖南省防灾科技有限公司湖南长沙410129

采用1∶1全尺寸特高压换流变压器实体火模型,开展添加水系灭火剂的水喷雾灭火系统灭特高压换流变压器全尺寸实体火的试验研究,提出已安装水喷雾灭火系统换流站的消防改造方案,以及水喷雾灭火系统抗烧和抗爆能力提升的解决方案,提升特高... 详细信息

采用1∶1全尺寸特高压换流变压器实体火模型,开展添加水系灭火剂的水喷雾灭火系统灭特高压换流变压器全尺寸实体火的试验研究,提出已安装水喷雾灭火系统换流站的消防改造方案,以及水喷雾灭火系统抗烧和抗爆能力提升的解决方案,提升特高压换流变压器消防能力。结果表明,在美国防火协会标准的水喷雾灭火系统设计标准下,添加6%水系灭火剂的水喷雾灭火系统仅34 s就扑灭了全尺寸特高压换流变压器实体火,验证了添加水系灭火剂的水喷雾灭火系统的灭火能力。

关键词：特高压换流变压器水系灭火剂水喷雾灭火换流站

同方期刊数据库博看期刊评论

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压铸镁合金激光堆焊层的组织与力学性能

热加工工艺 2015年第15期44卷 42-44,48页

作者：倪加明杨学勤罗志强李宝辉黄坚上海航天精密机械研究所上海201600 上海交通大学上海市激光制造与材料改性重点实验室上海200240

采用光纤激光填丝焊接技术进行压铸镁合金薄壁构件的缺陷补焊,利用扫描电镜和拉伸试验机进行分析与测定,着重研究了激光功率对补焊层组织及力学行为的影响规律。结果表明,通过方案和工艺参数优化,获得了成形良好的多层多道焊缝,未发现... 详细信息

采用光纤激光填丝焊接技术进行压铸镁合金薄壁构件的缺陷补焊,利用扫描电镜和拉伸试验机进行分析与测定,着重研究了激光功率对补焊层组织及力学行为的影响规律。结果表明,通过方案和工艺参数优化,获得了成形良好的多层多道焊缝,未发现裂纹和夹杂缺陷。激光填丝补焊层以α-Mg树枝晶为基体,其上分布粒状、棒状的β-Mg17Al12强化相颗粒。由于晶粒细小,激光补焊层焊缝组织拥有良好的强韧性。激光功率=2.4 k W时,拉伸断裂强度高达250 MPa,伸长率为8.6%,优于母材铸造组织。然而,激光功率≥2.6 k W时,母材熔化过多,将导致焊缝性能恶化。

关键词：激光填丝焊接压铸镁合金缺陷修补多层多道

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镁合金电弧熔丝增材成形质量控制研究

热加工工艺 2021年第13期50卷 128-132页

作者：倪加明刘思余李志豪王锋华李宝辉上海航天精密机械研究所上海201600 上海交通大学材料学院国家轻合金精密成型国家工程研究中心上海200240

针对镁合金CMT电弧增材制造表面成形质量控制难题,开展了AZ31镁合金电弧熔丝增材制造的沉积行为、成形特性研究,以及单道多层增材构件表面质量控制试验。结果表明:镁合金电弧增材制造的工艺参数优选范围较大,电流为120~160 A、沉积速度... 详细信息

针对镁合金CMT电弧增材制造表面成形质量控制难题,开展了AZ31镁合金电弧熔丝增材制造的沉积行为、成形特性研究,以及单道多层增材构件表面质量控制试验。结果表明:镁合金电弧增材制造的工艺参数优选范围较大,电流为120~160 A、沉积速度为10~12 mm/s时,沉积层宽度均匀一致,宽高比和接触角也较大;采用CMT工艺制备的镁合金单道多层增材试样力学性能无明显各向异性,抗拉强度为243 MPa,屈服强度为109 MPa,断后伸长率在23%左右,显微硬度平均值为57 HV。

关键词：镁合金电弧熔丝增材成形沉积行为

Agronomical selection on loss-of-function of GIGANTEA simultaneously facilitates soybean salt tolerance and early maturity

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Journal of Integrative Plant Biology 2022年第10期64卷 1866-1882页

作者： lidong Dong Zhihong Hou Haiyang li Zhaobo li Chao Fang lingping Kong Yongli li Hao Du Tai li lingshuang Wang Milan He Xiaohui Zhao Qun Cheng Fanjiang Kong baohui liu Guangdong Key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life SciencesGuangzhou UniversityGuangzhou Higher Education Mega Center230 Waihuanxi RoadGuangzhou 510006China The Innovative Academy of Seed Design Key Laboratory of Soybean Molecular Design BreedingNortheast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081China College of Agriculture Heilongjiang Bayi Agricultural UniversityDaqingChina National Key Laboratory of Crop Genetics and Germplasm Enhancement National Center for Soybean ImprovementJiangsu Collaborative Innovation Center for Modern Crop ProductionNanjing Agricultural UniversityNanjing 210095China College of Agriculture Jilin Agricultural Science and Technology UniversityJilin 132101China

Salt stress and flowering time are major factors limiting geographic adaptation and yield productivity in soybean(Glycine max).Although improving crop salt tolerance and latitude adaptation are essential for efficient agricultural production,whether and how these two traits are integrated remains largely unknown.Here,we used a genome-wide association study to identify a major salt-tolerance locus controlled by E2,an ortholog of Arabidopsis thaliana GIGANTEA(GI).Loss of E2 function not only shortened flowering time and maturity,but also enhanced salt-tolerance in soybean.E2 delayed soybean flowering by enhancing the transcription of the core flowering suppressor gene E1,thereby repressing Flowering Locus T(FT)expression.An E2 knockout mutant e2^(CR) displayed reduced accumulation of reactive oxygen species(ROS)during the response to salt stress by releasing peroxidase,which functions in ROS scavenging to avoid cytotoxicity.Evolutionary and population genetic analyses also suggested that loss-of-function e2 alleles have been artificially selected during breeding for soybean adaptation to high-latitude regions with greater salt stress.Our findings provide insights into the coupled selection for adaptation to both latitude and salt stress in soybean;and offer an ideal target for molecular breeding of early-maturing and salt-tolerant cultivars.

关键词： floweringtime GIGANTEA ROS saltstress soybean

GIGANTEA orthologs,E2 members,redundantly determine photoperiodic flowering and yield in soybean

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Journal of Integrative Plant Biology 2023年第1期65卷 188-202页

作者： lingshuang Wang Haiyang li Milan He lidong Dong Zerong Huang liyu Chen Haiyang Nan Fanjiang Kong baohui liu Xiaohui Zhao Guangdong Key Laboratory of Plant Adaptation and Molecular Design Guangzhou Key Laboratory of Crop Gene EditingInnovative Center of Molecular Genetics and EvolutionSchool of Life Sciences Guangzhou UniversityGuangzhou 510006 China National Key Laboratory of Crop Genetics and Germplasm Enhancement National Center for Soybean ImprovementJiangsu Collaborative Innovation Center for Modern Crop Production Nanjing Agricultural UniversityNanjing 210095 China

Soybean(Glycine max L.)is a typical photoperiodsensitive crop,such that photoperiod determines its flowering time,maturity,grain yield,and phenological adaptability.During evolution,the soybean genome has undergone two duplication events,resulting in about 75%of all genes being represented by multiple copies,which is associated with rampant gene redundancy.Among duplicated genes,the important soybean maturity gene E2 has two homologs,E2-like a(E2La)and E2-like b(E2Lb),which encode orthologs of Arabidopsis GIGANTEA(GI).Although E2 was cloned a decade ago,we still know very little about its contribution to flowering time and even less about the function of its homologs.Here,we generated single and double mutants in E2,E2La,and E2Lb by genome editing and determined that E2 plays major roles in the regulation of flowering time and yield,with the two E2 homologs depending on E2 function.At high latitude regions,e2 single mutants showed earlier flowering and high grain yield.Remarkably,in terms of genetic relationship,genes from the legume-specific transcription factor family E1 were epistatic to E2.We established that E2 and E2-like proteins form homodimers or heterodimers to regulate the transcription of E1 family genes,with the homodimer exerting a greater function than the heterodimers.In addition,we established that the H3 haplotype of E2 is the ancestral allele and is mainly restricted to low latitude regions,from which the loss-of-function alleles of the H1 and H2haplotypes were derived.Furthermore,we demonstrated that the function of the H3 allele is stronger than that of the H1 haplotype in the regulation of flowering time,which has not been shown before.Our findings provide excellent allelic combinations for classical breeding and targeted gene disruption or editing.

关键词： E2 E2-like flowering time GIGANTEA natural variation redundancy yield

Puerarin@Chitosan composite for infected bone repair through mimicking the bio-functions of antimicrobial peptides

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Bioactive Materials 2023年第3期21卷 520-530页

作者： liping Ouyang baohui Chen Xingdan liu Donghui Wang Yang li Yun liao Kelvin W.K.Yeung Xuanyong liu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Hongqiao International Institute of edicine Shanghai Jiao Tong University School of MedicineShanghai200336China Cixi Center of Biomaterials Surface Engineering Ningbo315300China Department of Computational Biology for Individualised Medicine Centre for Individualised Infection Medicine(CiiM)&TWINCOREJoint Ventures Between the Helmholtz-Centre for Infection Research(HZI)and the Hannover Medical School(MHH)HannoverGermany Shenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma Guangdong Engineering Technology Research Center for Orthopaedic Trauma RepairDepartment of Orthopaedics and TraumatologyThe University of Hong Kong Shenzhen HospitalShenzhenChina

It is important to eliminate lipopolysaccharide(LPS)along with killing bacteria in periprosthetic joint infection(PJI)therapy for promoting bone repair due to its effect to regulate macrophages response.Although natural antimicrobial peptides(AMPs)offer a good solution,the unknown toxicity,high cost and exogenetic immune response hamper their applications in clinic.In this work,we fabricated a nanowire-like composite material,named P@C,by combining chitosan and puerarin via solid-phase reaction,which can finely mimic the bio-functions of AMPs.Chitosan,serving as the bacteria membrane puncture agent,and puerarin,serving as the LPS target agent,synergistically destroy the bacterial membrane structure and inhibit its recovery,thus endowing P@C with good antibacterial property.In addition,P@C possesses good osteoimmunomodulation due to its ability of LPS elimination and macrophage differentiation modulation.The in vivo results show that P@C can inhibit the LPS induced bone destruction in the Escherichia coli infected rat.P@C exhibits superior bone regeneration in Escherichia coli infected rat due to the comprehensive functions of its superior antibacterial property,and its ability of LPS elimination and immunomodulation.P@C can well mimic the functions of AMPs,which provides a novel and effective method for treating the PJI in clinic.

关键词： Osteoimmunomodulation Antibacterial Chitosan Puerarin lipopolysaccharide