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Journal of Integrative Agriculture 2024年第3期23卷 849-862页

作者： Jiawei Pan Jia Song Rahat Sharif Xuewen Xu shutong li Xuehao Chen School of Horticulture and Landscape Architecture Yangzhou UniversityYangzhou 225009China Institute of Vegetables Tianjin Academy of Agricultural SciencesTianjin 300384China

Leaf color mutants in higher plants are considered to be ideal materials for studying the chlorophyll biosynthesis,photosynthesis mechanism and chloroplast ***,we identified a spontaneous mutant,yc412,in cultivated cucumber that exhibited yellow *** yellow-lethal mutant was diagnosed with an abnormal chloroplast ultrastructure,and reduced photosynthetic capacity and pigment *** bulked segregant analysis-based whole-genome sequencing and fine genetic mapping,we narrowed the yellow cotyledons (yc) locus to a 96.8 kb interval on chromosome *** resequencing and molecular cloning,we showed that Csyc is a potential candidate gene,which encodes a yellow stripe-like (YSL) *** T to C mutation in the promoter region of Csyc caused the yellow cotyledon phenotype in *** to YZU027A (WT),the expression of Csyc was significantly downregulated in the cotyledons of *** of Csyc in cucumber via virus-induced gene silencing resulted in chlorotic leaves,mainly by suppressing the chlorophyll ***,a comparative transcriptome analysis revealed that chloroplast-related genes and chlorophyll biosynthesis genes were significantly downregulated in yc412 *** results provide new insights into the molecular function of the YSL transporter in plant chloroplast development and chlorophyll synthesis.

关键词： cucumber yellow-lethal cotyledons chloroplast development yellow stripe-like transporter

Experimental study on the movement of oil spill under freeze-thaw action

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Research in Cold and Arid Regions 2024年第3期16卷 111-120页

作者： Zeliang Ye JianGuo Lu MingYi Zhang WanSheng Pei shutong li State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengduSichuan 610500China

Oil leakages cause environmental pollution,economic losses,and even engineering safety *** cold regions,researchers urgently investigate the movement of oil spill in soils exposed to freeze-thaw *** this study,a series of laboratory model experiments were carried out on the migration of oil leakage under freeze-thaw action,and the distributions of the soil temperature,unfrozen water content,and displacement were *** results showed that under freeze-thaw action,liquid water in soils migrated to the freezing front and *** the pipe cracked,oil pollutants first gathered at one side of the leak hole,and then moved *** pipe wall temperature affected the soil temperature field,and the thermal influence range below and transverse the pipe wall(35–40 cm)was larger than that above the pipe wall(8 cm)owing to the soil surface *** leaked oil's temperature would make the temperature of the surrounding soil *** would inhibit the cooling of the ***,oil migration was significantly affected by the gravity and water flow *** freeze-thaw action would affect the migration of the oil,which was mainly manifested as inhibiting the diffusion and movement of oil when soils were *** water transport caused by freeze-thaw cycles would also inhibit oil *** research results would provide a scientific reference for understanding the relationship between the movement of oil pollutants,water,and soil temperature,and for establishing a waterheat-mass transport model in frozen soils.

关键词： Freeze-thaw action Oil movement Soil temperature Unfrozen water content Model test

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周期性剪切应力作用下碎石的滑移特性

中山大学学报（自然科学版）（中英文） 2024年第5期63卷 131-139页

作者：廖纤陶康刘煜李舒彤党文刚中山大学土木工程学院广东珠海5190822.弗莱贝格工业大学岩土工程研究所德国弗莱贝格09599

为了研究碎石材料在周期性剪切荷载条件下的滑移特性,使用自主研发的多功能动剪试验机,对碎石试样施加恒定的法向应力,以及不同峰值、谷值和频率的水平方向周期性剪切应力,监测试样在加载过程中剪切位移随时间的变化情况,并分析剪切位... 详细信息

为了研究碎石材料在周期性剪切荷载条件下的滑移特性,使用自主研发的多功能动剪试验机,对碎石试样施加恒定的法向应力,以及不同峰值、谷值和频率的水平方向周期性剪切应力,监测试样在加载过程中剪切位移随时间的变化情况,并分析剪切位移增量的变化情况以及整个加载期内剪切应力对应的能量密度。研究结果表明:周期性剪切应力引起的滑移特征与其峰值、谷值和频率有关;周期性剪切应力会导致碎石材料的滑移跃变,且出现滑移跃变点的条件与加载期内的能量密度有关,可根据能量密度范围将试样的滑移状态划分为三个区域,即稳定区、过渡区和跃变区。

关键词：碎石路基周期性剪切应力多功能动剪试验机滑移特性剪切位移能量密度

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Suppressing the ferroelectric switching barrier in hybrid improper ferroelectrics

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npj Computational Materials 2020年第1期6卷 287-296页

作者： shutong li Turan Birol Department of Chemical Engineering and Materials Science University of MinnesotaMinneapolisMN 55455USA

Integration of ferroelectric materials into novel technological applications requires low coercive field materials,and consequently,design strategies to reduce the ferroelectric switching *** this first principles study,we show that biaxial strain,which has a strong effect on the ferroelectric ground states,can also be used to tune the switching barrier of hybrid improper ferroelectric Ruddlesden–Popper *** identify the region of the strain-tolerance factor phase diagram where this intrinsic barrier is suppressed,and show that it can be explained in relation to strain-induced phase transitions to nonpolar phases.

关键词： ferroelectric transitions explained

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黏结剂辅助微流控芯片异种键合及可行性探究

工程塑料应用 2024年第1期52卷 77-83页

作者：李疏桐刘坡黄继杰韩鹏彪河北科技大学材料科学与工程学院河北省材料近净成形技术重点实验室石家庄050018 桂林航天工业学院机电工程学院广西桂林541004

以聚甲基丙烯酸甲酯(PMMA)、聚苯乙烯(PS)、铝合金Al5052为研究对象,采用黏结剂与热压键合相结合的方法,分别进行了PMMA-PS、PMMA-Al5052异种键合正交实验。旨在探讨键合层厚度及表观形貌的变化规律,研究键合温度、压力和时间对异种键... 详细信息

以聚甲基丙烯酸甲酯(PMMA)、聚苯乙烯(PS)、铝合金Al5052为研究对象,采用黏结剂与热压键合相结合的方法,分别进行了PMMA-PS、PMMA-Al5052异种键合正交实验。旨在探讨键合层厚度及表观形貌的变化规律,研究键合温度、压力和时间对异种键合强度的影响。结果表明:键合层厚度随温度和压力的增大而减小,而时间对键合层厚度无明显影响;聚酰亚胺(PI)辅助PMMA-PS和PMMA-Al5052的键合强度受时间影响最大,温度次之,压力最小;而溶解PMMA粉末的丙酮溶液[丙酮溶液(PMMA)]辅助PMMA-Al5052的键合强度受压力影响最大,温度次之,时间最小;同参数下PMMA-PS的键合强度远高于PMMA-Al5052。分别确立了异种键合的最优参数并得到了对应的键合强度:PI辅助PMMA-PS键合的最优参数为105℃,50 min,2.5 MPa,对应键合强度0.87 MPa;PI辅助PMMA-Al5052键合的最优参数为110℃,50 min,1.25 MPa,对应键合强度0.21 MPa;丙酮溶液(PMMA)辅助PMMA-Al5052键合的最优参数为110℃,2.5 MPa,20 min,对应键合强度0.41 MPa,均高于正交实验设计方案中的所有结果。参数一定时,PMMA-PS的键合强度远高于PMMA-Al5052的键合强度。采用丙酮溶液(PMMA)辅助键合PMMA-Al5052时,键合强度高于PI辅助的键合强度。

关键词：异种键合黏结剂聚甲基丙烯酸甲酯聚苯乙烯 Al5052 键合层形貌键合强度

A Preliminary Investigation of Arctic Sea Ice Negative Freeboard from in-situ Observations and Radar Altimetry

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Journal of Ocean University of China 2021年第2期20卷 307-314页

作者： li shutong DOU Tingfeng XIAO Cunde State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Land Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

The negative freeboard of sea ice(i.e., the height of ice surface below sea level) with subsequent flooding is widespread in the Southern Ocean, as opposed to the Arctic, due to the relatively thicker ice and thinner snow. In this study, we used the observations of snow and ice thickness from 103 ice mass balance buoys(IMBs) and NASA Operation IceBridge Aircraft Missions to investigate the spatial distribution of negative freeboard of Arctic sea ice. The Result showed that seven IMBs recorded negative freeboards, which were sporadically located in the seas around Northeast Greenland, the Central Arctic Ocean, and the marginal areas of the Chukchi–Beaufort Sea. The observed maximum values of negative freeboard could reach-0.12 m in the seas around Northeast Greenland. The observations from IceBridge campaigns also revealed negative freeboard comparable to those of IMBs in the seas around North Greenland and the Beaufort Sea. We further investigated the large-scale distribution of negative freeboard using NASA CryoSat-2 radar altimeter data, and the result indicates that except for the negative freeboard areas observed by IMBs and IceBridge, there are negative freeboards in other marginal seas of the Arctic Ocean. However, the comparison of the satellite data with the IMB data and IceBridge data shows that the Cryosat-2 data generally overestimate the extent and magnitude of the negative freeboard in the Arctic.

关键词： Arctic sea ice negative freeboard ice mass balance buoy IceBridge CryoSat-2

Ni@C/CN纳米催化剂用于降解芳香族硝基化合物和有毒有机染料

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沈阳师范大学学报（自然科学版） 2024年第2期42卷 108-113页

作者：王颖史桂梅李姝潼沈阳工业大学理学院沈阳110870

采用电弧放电法结合热解技术设计并合成了Ni@C/CN纳米催化剂。采用透射电镜、X射线衍射、X射线光电子能谱、电化学工作站对Ni@C/CN的微观结构和电子传输能力进行了研究;利用紫外-可见分光光度计研究了所制备的催化剂对芳香族硝基化合物... 详细信息

采用电弧放电法结合热解技术设计并合成了Ni@C/CN纳米催化剂。采用透射电镜、X射线衍射、X射线光电子能谱、电化学工作站对Ni@C/CN的微观结构和电子传输能力进行了研究;利用紫外-可见分光光度计研究了所制备的催化剂对芳香族硝基化合物(对硝基苯酚(4-NP)和有机染料(亚甲基兰))的催化还原性能。结果表明,Ni@C/CN纳米催化剂比Ni@C纳米胶囊具有更好的催化还原性能;通过优化Ni@C纳米胶囊和三聚氰胺的质量比可以优化Ni@C/CN的催化性能,优化后的Ni@C/CN催化还原降解4-NP和MB的准一级反应速率常数(k_(app))分别为4.656 min^(-1)和13.879 min^(-1);N的引入及异质C/CN壳层包覆金属Ni使Ni@C/CN获得良好的核壳协同作用,提高了Ni@C/CN的电子传输能力,同时,CN的表面缺陷增强了催化剂的吸附性能,增强了Ni@C/CN的催化还原能力。

关键词： Ni/C基纳米催化剂催化还原芳香族硝基化合物有机染料

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大庆喇嘛甸油田低碳示范区建设探索与实践

石油科技论坛 2024年第1期43卷 103-108页

作者：李兴国阚宝春李姝桐大庆油田有限责任公司第六采油厂帝国理工大学材料科学系

“双碳”背景下,大庆油田全力构建清洁高效的能源体系,打造千万千瓦级新能源基地。喇嘛甸油田结合特高含水开发及整装油田典型特点,依托资源优势,探索建设喇北北块低碳示范区。以全面能源调查为基础,明确将灰电与天然气作为替代目标,确... 详细信息

“双碳”背景下,大庆油田全力构建清洁高效的能源体系,打造千万千瓦级新能源基地。喇嘛甸油田结合特高含水开发及整装油田典型特点,依托资源优势,探索建设喇北北块低碳示范区。以全面能源调查为基础,明确将灰电与天然气作为替代目标,确定了“节能降碳、清洁替碳”两步走建设思路。结合油田用热特点,整体部署油田余热、地热、光热及电热多能互补方案,全面实施工艺流程再造、立体化节能、清洁热能替代、清洁电能替代。根据油田中部地区管网密度大、周边可利用土地多的特点,以最大发电量、最小弃电量为目标,整体优化风光发电建设布局和规模,以实现区域多能互补、供用能平衡及高替代率。低碳示范区将新能源技术与现有生产工艺深化融合,开展了先导性的储能、制氢、微电网、能源管控技术研究。低碳示范区预期2025年全面建成,清洁能源替代率将达到46.4%,将有力推动油田能源变革、绿色低碳转型。

关键词：低碳示范区节能减排清洁替代多能互补喇嘛甸油田

利用Ti/Ag中间层实现金刚石与GaN的室温键合

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表面技术 2024年第18期53卷 175-182页

作者：乔冠中李淑同王越刘金龙陈良贤魏俊俊李成明北京科技大学新材料技术研究院北京100083 北京科技大学顺德创新学院广东佛山528399

目的为了实现金刚石与GaN的良好键合,利用Ti/Ag中间层,在室温下开展了多晶金刚石与GaN的键合技术研究。方法首先,分别在抛光自支撑多晶金刚石晶圆以及GaN晶圆表面,通过磁控溅射依次沉积Ti黏附层、Ti/Ag梯度层以及纳米Ag层,形成Ti/Ag过... 详细信息

目的为了实现金刚石与GaN的良好键合,利用Ti/Ag中间层,在室温下开展了多晶金刚石与GaN的键合技术研究。方法首先,分别在抛光自支撑多晶金刚石晶圆以及GaN晶圆表面,通过磁控溅射依次沉积Ti黏附层、Ti/Ag梯度层以及纳米Ag层,形成Ti/Ag过渡层复合结构。然后通过真空键合系统成功实现了金刚石与Ga N键合。通过扫描电子显微镜(SEM)、原子力显微镜(AFM)、X射线衍射(XRD)以及X射线光电子能谱(XPS)等表征手段,对键合前后样品表面进行形貌及结构分析;通过超声扫描显微镜(SAM),以及拉伸力学测试系统,对键合后的键合率以及键合强度进行评价。结果借助Ti/Ag中间层进行键合,对晶圆表面的粗糙度具有较高容忍度,且在常温下即能实现良好键合,室温键合率达到95.5%。通过拉伸强度测试可知,键合强度达到13.7MPa。结论Ag纳米颗粒高的表面活性是实现键合界面常温融合的关键,而Ti底层良好的附着特性,Ti/Ag梯度层的引入以及Ti与Ag之间通过扩散反应形成的金属间化合物,则是提高金刚石与GaN键合强度的关键因素。

关键词：金刚石氮化镓 Ti/Ag中间层室温键合金属间化合物

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压力对稠油拟组分氧化的影响

特种油气藏 2024年第3期31卷 129-135页

作者：陈莉娟李舒彤陈龙王田田潘竟军赵仁保中国石油新疆油田分公司新疆克拉玛依834000 中国石油大学(北京)油气资源与工程国家重点实验室北京102249 中国石油大学(北京)克拉玛依校区新疆克拉玛依834000

为进一步明确稠油火驱过程中的反应动力学行为和产出原油组分变化规律,通过实沸点蒸馏法将新疆红浅1井区稠油划分为不同沸程的拟组分,研究了体系压力对沸程高于350℃的稠油拟组分氧化行为的影响,并在线性升温条件下进行燃烧池实验,研究... 详细信息

为进一步明确稠油火驱过程中的反应动力学行为和产出原油组分变化规律,通过实沸点蒸馏法将新疆红浅1井区稠油划分为不同沸程的拟组分,研究了体系压力对沸程高于350℃的稠油拟组分氧化行为的影响,并在线性升温条件下进行燃烧池实验,研究体系压力对稠油各拟组分与空气反应时的产气体积分数、温度和放热量的变化规律。结果表明:体系压力对低温氧化阶段的加氧反应和脱羧反应有显著影响,且对低沸程拟组分的影响更加明显;沸程为350~420℃的拟组分在体系压力为3.0 MPa时的CO+CO_(2)生成量是其在1.0 MPa时的10倍;高沸程拟组分虽然受体系压力影响较小,但沸程大于500℃的拟组分的放热量可高达12.26 kJ/g;稠油火驱的改质效果取决于重质组分的消耗量和裂解反应。研究结果为火驱过程中稠油组分的缺失情况和油藏温度的合理分析及预测提供了借鉴。

关键词：火驱稠油燃烧池低温氧化拟组分体系压力