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稻麦复种模式下氮肥与稻秸互作对小麦产量和N_(2)O排放影响及推荐施肥研究
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作者 陆汝华 王文轩 +4 位作者 曹强 田永超 朱艳 曹卫星 刘小军 《作物学报》 CAS CSCD 北大核心 2024年第5期1300-1311,共12页
优化氮肥施用和秸秆还田技术为途径的农业管理措施被认为是提升农业可持续性的有效手段,然而当前关于氮肥和秸秆还田对小麦产量和N_(2)O排放影响的研究仍十分有限。为此,本研究基于2000—2022年发表的关于长江中下游流域氮肥和秸秆投入... 优化氮肥施用和秸秆还田技术为途径的农业管理措施被认为是提升农业可持续性的有效手段,然而当前关于氮肥和秸秆还田对小麦产量和N_(2)O排放影响的研究仍十分有限。为此,本研究基于2000—2022年发表的关于长江中下游流域氮肥和秸秆投入下小麦产量和N_(2)O排放变化的文献,运用随机森林建模,定量分析氮肥和秸秆还田对小麦产量和N_(2)O排放的影响,并结合情景设置进行了特定地点的小麦产量和N_(2)O排放模拟,同时评估了碳排放强度(CEE)和净生态系统经济效益(NEEB)。结果表明,建立的区域尺度小麦产量与N_(2)O排放对氮秸互作响应的随机森林模型,验证结果R^(2)分别为0.66和0.65,RMSE分别为0.70和1.11。结果表明施氮量和土壤有机质是影响小麦产量和N_(2)O排放的重要因素。综合来看,达到最大产量所需的氮肥量为208~212 kg hm^(-2),达到最小CEE所需的氮肥量为113~130 kg hm^(-2),达到最高的NEEB所需的氮肥量为202~205 kg hm^(-2),其中在6.75 t hm^(-2)的秸秆投入下施用202 kg hm^(-2)的氮肥可以获得最高的生态收益1.37万元。优化氮肥和秸秆投入具备减少作物碳排放强度并获得最大净生态环境效益的潜力。 展开更多
关键词 施氮量 秸秆投入 小麦 N_(2)o 排放模型 推荐施肥
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某型飞机舱盖关键元件O形密封圈气密性分析
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作者 任义志 耿浩壮 +2 位作者 权凌霄 皮月亮 程瑞 《液压与气动》 北大核心 2024年第8期137-145,共9页
对某飞机舱盖作动筒异常弹出进行分析,原因是油液中的气体导致油液体积弹性模量变小,可压缩性增强,易发生弹出现象。基于IFAS模型得到含气量与油液体积弹性模量的关系。座舱盖液压操纵系统密封区域均采用O形密封圈进行密封,但由于关键... 对某飞机舱盖作动筒异常弹出进行分析,原因是油液中的气体导致油液体积弹性模量变小,可压缩性增强,易发生弹出现象。基于IFAS模型得到含气量与油液体积弹性模量的关系。座舱盖液压操纵系统密封区域均采用O形密封圈进行密封,但由于关键元件粗糙表面特征的存在构成气体泄漏通道,导致座舱盖液压操纵系统中混入气体。因此提出了一种基于Roth模型的泄漏率计算方法,将O形密封圈与金属粗糙表面之间的接触关系,看作弹性金属光滑表面和刚性金属粗糙表面之间的接触关系,对金属粗糙度表面轮廓三角峰均一化排列,从而将泄漏路径定义为梯形通道。基于有限元软件ABAQUS计算密封圈的密封性能系数,分析了表面粗糙度及偏载情况对气体泄漏率的影响;最后通过ANSYS仿真分析与理论结果进行对比。该工作对高精密的密封结构加工设计有着重要指导意义。 展开更多
关键词 o形密封圈 表面粗糙度 Roth模型 密封性能系数 气体泄漏率
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施氮对陇中黄土高原旱作麦田N_(2)O和CO_(2)排放的影响
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作者 何锦煜 袁建钰 +4 位作者 闫丽娟 杜梦寅 庞晔 成思潮 李广 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第3期81-89,共9页
【目的】探究陇中黄土高原半干旱区旱作麦田土壤N_(2)O和CO_(2)排放对不同施氮量的响应,阐明旱作麦田N_(2)O和CO_(2)排放特征及其主要影响因素,以期为该地区旱作麦田温室气体减排和氮肥管理提供依据。【方法】以陇中黄土高原旱作麦田为... 【目的】探究陇中黄土高原半干旱区旱作麦田土壤N_(2)O和CO_(2)排放对不同施氮量的响应,阐明旱作麦田N_(2)O和CO_(2)排放特征及其主要影响因素,以期为该地区旱作麦田温室气体减排和氮肥管理提供依据。【方法】以陇中黄土高原旱作麦田为研究对象,采用大田定位试验和室内指标测定相结合的方法,布设CK(不施肥)、LN(低量氮肥)、MN(中量氮肥)和HN(高量氮肥)共4个施氮梯度,分析不同施氮量对旱作麦田土壤硝态氮(NO_(3)^(-)-N)、铵态氮(NH_(4)^(+)-N)、有机碳(SOC)、土壤温度、含水量及土壤N_(2)O和CO_(2)排放的影响。【结果】0~10 cm土层土壤中,HN、MN、LN较CK处理,NO_(3)^(-)-N平均含量增幅为21.55%、26.06%和34.11%;NH_(4)^(+)-N平均含量增幅为21.77%、31.42%和39.20%;SOC平均含量增幅为20.43%、25.80%和35.9%。HN、MN、LN较CK处理,N_(2)O累计排放量增幅为78.63%、130.47%、217.51%;CO_(2)累计排放量增幅为5.73%、10.63%、21.75%。皮尔逊相关关系表明,不同施氮处理中,麦田0~10 cm土层土壤中NO_(3)^(-)-N、NH_(4)^(+)-N和SOC平均含量与N_(2)O、CO_(2)累计排放量呈极显著正相关关系(P<0.001),土壤温度与N_(2)O和CO_(2)累计排放量呈显著正相关关系(P<0.05),土壤含水量与N_(2)O累计排放量呈显著的负相关关系(P<0.05),与CO_(2)累计排放量相关关系不显著。【结论】施氮可以增加黄土高原旱作麦田表层土壤中NO_(3)^(-)-N、NH_(4)^(+)-N和SOC含量,进而增加了N_(2)O和CO_(2)累计排放量,是该地区麦田N_(2)O和CO_(2)排放的主要驱动因子,表层土温和土壤含水量也一定程度上影响着N_(2)O和CO_(2)的排放。 展开更多
关键词 旱作麦田 施氮量 N_(2)o Co_(2) 排放通量 陇中黄土高原
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Effect of sintering temperature on cycling performance and rate performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 被引量:2
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作者 李向群 熊训辉 +1 位作者 王志兴 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期4023-4029,共7页
LiNi0.8Co0.1Mn0.1O2 powder was prepared by mixing LiOH·H2O and co-precipitated Ni0.8Co0.1Mn0.1(OH)2 at a molar ratio of 1:1.05, followed by sintering at different temperatures. The effects of temperature on th... LiNi0.8Co0.1Mn0.1O2 powder was prepared by mixing LiOH·H2O and co-precipitated Ni0.8Co0.1Mn0.1(OH)2 at a molar ratio of 1:1.05, followed by sintering at different temperatures. The effects of temperature on the morphology, structure and electrochemical performance were extensively studied. SEM and XRD results demonstrate that the sintering temperature has large influence on the morphology and structure and suitable temperature is very important to obtain spherical materials and suppresses the ionic distribution. The charge-discharge tests show that the electrochemical performance of LiNi0.8Co0.1Mn0.1O2 powders becomes better with the increase of temperature from 700 ℃ to 750 ℃ and higher temperature will deteriorate the performance. Although both of materials obtained at 750 ℃ and 780 ℃ demonstrate almost identical cyclic stability at 2C rate, which delivers 71.9%retention after 200 cycles, the rate performance of powder calcined at 780 ℃ is much poorer than that at 750 ℃. The XRD results demonstrate that the poor performance is ascribed to more severe ionic distribution caused by higher temperature. 展开更多
关键词 lithium ion battery LiNi0.8Co0.1Mn0.1o2 sintering temperature cycling performance rate performance
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Supercritical-hydrothermal accelerated solid state reaction route for synthesis of LiMn_2O_4 cathode material for high-power Li-ion batteries 被引量:1
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作者 刘学武 汤洁 +2 位作者 覃旭松 邓远富 陈国华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1414-1424,共11页
Synthesis of the spinel structure lithium manganese oxide (LiMn2O4) by supercritical hydrothermal (SH) accelerated solid state reaction (SSR) route was studied. The impacts of the reaction pressure, reaction tem... Synthesis of the spinel structure lithium manganese oxide (LiMn2O4) by supercritical hydrothermal (SH) accelerated solid state reaction (SSR) route was studied. The impacts of the reaction pressure, reaction temperature and reaction time of SH route, and the calcination temperature of SSR route on the purity, particle morphology and electrochemical properties of the prepared LiMn2O4 materials were studied. The experimental results show that after 15 min reaction in SH route at 400 ℃ and 30 MPa, the reaction time of SSR could be significantly decreased, e.g. down to 3 h with the formation temperature of 800 ℃, compared with the conventional solid state reaction method. The prepared LiMn2O4 material exhibits good crystallinity, uniform size distribution and good electrochemical performance, and has an initial specific capacity of 120 mA.h/g at a rate of 0.1C (1C=148 mA/g) and a good rate capability at high rates, even up to 50C. 展开更多
关键词 lithium ion battery LIMN2o4 supercritical water solid state reaction high rate capability
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Effect of water stress on N_2O emission rate of 5 tree species
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作者 王淼 李秋荣 +1 位作者 肖冬梅 王长科 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期19-23,J001,共6页
The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed ... The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed bag-gas chromatography. A total of five species seedlings were involved in this study, i.e.,Pinus koraiensis Sieb. et Zucc,Fraxinus mandshurica Rupr,Juglans mandshurica Maxim,Tilia amurensis Rupr, andQuercus mongolica Fisch. ex Turcz.. The results showed that the stomatal conductance, net photosynthetic rate and N2O emission of leaves were significantly reduced under the water stress. The stoma in the leaves of trees is the main pathway of N2O emission. N2O emission in the trees mainly occurred during daytime. N2O emission rates were different in various tree specie seedlings at the same water status. In the same tree species, N2O emission rates decreased as the reduction of soil water contents. At different soil water contents (MW, LW) the N2O emission rates ofPinus koraiensis decreased by 34.43% and 100.6% of those in normal water condition, respectively. In broadleaf arbor decreased by 31.93% and 86.35%, respectively. Under different water stresses N2O emission rates in five tree species such asPinus koraiensis, Fraxinus mandshurica, Juglans mandshurica, Tilia amurensis, andQuercus mongolica were 38.22, 14.44, 33.02, 16.48 and 32.33 ngN2O·g?1DW·h?1, respectively. Keywords Trees - N2O emission rate - Soil water stress - broadleaf/Korean pine forest - Changbai Mountain CLC number S718.55 Document code A Foundation item: This project was supported by the National Natural Science Foundation of China (No. 30271068), the grant of the Knowledge Innovation Program of Chinese Academy of Sciences (KZ-CX-SW-01-01B-10), and the Special Funds for Major State Basic Research Program of China (No. G1999043407)Biography: Wang Miao (1964-), male, associate professor in Institute of Applied Ecology, Chinese Academy of Science, Shenyang 110016, P. R. China.Responsible editor: Song Funan 展开更多
关键词 Trees N2o emission rate Soil water stress broadleaf/Korean pine forest Changbai Mountain
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微塑料对序批式生物膜反应器除碳脱氮及N_(2)O释放特征的影响 被引量:2
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作者 杨雪梅 苏永祥 《水处理技术》 CAS CSCD 北大核心 2023年第2期93-97,共5页
微塑料是污水中常被检测到的新型污染物,然而微塑料对序批式生物膜反应器同步脱氮及N_(2)O释放特征的探究较少。本工作以实际市政废水为探究对象,建立中试规模的SBBR,考察了不同微塑料浓度(0、0.2、2.0和10.0mg/L)对SBBR长期运行除碳脱... 微塑料是污水中常被检测到的新型污染物,然而微塑料对序批式生物膜反应器同步脱氮及N_(2)O释放特征的探究较少。本工作以实际市政废水为探究对象,建立中试规模的SBBR,考察了不同微塑料浓度(0、0.2、2.0和10.0mg/L)对SBBR长期运行除碳脱氮效率及N_(2)O释放规律的影响,并揭示了相关影响机制。结果表明,低浓度微塑料对SBBR除碳脱氮效率及N_(2)O释放规律影响不明显,但当进水微塑料浓度超过2.0 mg/L,碳脱氮效率呈现下降趋势,N_(2)O产率增加。当微塑料浓度为10.0 mg/L时,稳定时期出水COD维持在35.3~37.9 mg/L,COD和NH_(4)^(+)-N去除效率分别下降至82.4%~83.5%和80.2%~82.3%,低于工况I,此外,N_(2)O产率高达10.2%~10.8%。内聚物分析表明高浓度微塑料降低了PHA和糖原质的净合成,进而导致内碳源消耗脱氮动力不足。比耗氧速率(SOUR)分析表明高浓度微塑料降低了全部微生物代谢活性。 展开更多
关键词 微塑料 生物脱氮 N_(2)o 糖原质 比耗氧速率
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碳烟边缘茚型五碳环与活性O的氧化反应机理研究
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作者 张韦 杨喜历 +3 位作者 孟利清 李泽宏 陈朝辉 宁硕 《燃烧科学与技术》 CAS CSCD 北大核心 2023年第1期1-10,共10页
针对碳烟在火焰中的氧化,本文利用DFT方法研究活性O氧化碳烟边缘茚型五碳环结构的反应机理.在B3LYP/6-311G(d,p)和M06-2X/cc-p VQZ的计算水平下,探究活性O与C_(13)H_(9)自由基的详细反应路径,并基于TST计算各基元反应在500~3 000 K温度... 针对碳烟在火焰中的氧化,本文利用DFT方法研究活性O氧化碳烟边缘茚型五碳环结构的反应机理.在B3LYP/6-311G(d,p)和M06-2X/cc-p VQZ的计算水平下,探究活性O与C_(13)H_(9)自由基的详细反应路径,并基于TST计算各基元反应在500~3 000 K温度范围内的速率常数.结果表明:活性O与C_(13)H_(9)自由基形成的C_(13)H_(9)O,进一步热解后将产生CHO、CO和具有四碳环结构的PAHs.CHO的生成高度依赖温度和反应位点,其反应需克服402.7 kJ/mol的限速步能垒.C_(13)H_(9)O热解的氧化产物主要为CO.M1和M2热解释放CO的主反应路径为路径3和12,并产生具有四碳环结构的CS9,对应的限速步能垒分别为167.9 kJ/mol和153.8 kJ/mol.C_(13)H_(9)O热解的起始反应主要为C—C键断键和H转移反应,其中C—C键断键的反应路径更易发生,且反应速率也更快. 展开更多
关键词 碳烟氧化 活性o 茚型五碳环 反应路径 反应速率
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提高RH路线钢种C-T-O命中率的生产实践
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作者 吴春红 王源 +1 位作者 宋细牙 王炜 《山西冶金》 CAS 2023年第4期135-137,共3页
通过对影响RH路线钢种C-T-O命中率的原因进行分析,找出其主要原因为到站温度不命中,然后针对性地对转炉冶炼过程的留渣、枪位、静态模型、动态模型、炉况及炉型维护进行了优化,使RH路线钢种C-T-O命中率由60.3%提高至82.6%,铝耗平均每月... 通过对影响RH路线钢种C-T-O命中率的原因进行分析,找出其主要原因为到站温度不命中,然后针对性地对转炉冶炼过程的留渣、枪位、静态模型、动态模型、炉况及炉型维护进行了优化,使RH路线钢种C-T-O命中率由60.3%提高至82.6%,铝耗平均每月下降6.2 t,非计划率下降了0.6%,直接经济效益达217余万元,同时为改善硅钢质量作出了突出贡献,取得了较好的经济和社会效益。 展开更多
关键词 留渣 自动炼钢模型 C-T-o命中率 炉型维护
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Comparison of burn rate and thermal decomposition of AP as oxidizer and PVC and HTPB as fuel binder based composite solid propellants 被引量:5
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作者 A.Manash P.Kumar 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第2期227-232,共6页
In the present investigation an effort has been made to understand the thermal decomposition and burn rate characteristics of AP as oxidizer and PVC and HTPB as fuel binder in composite solid propellant. The burning r... In the present investigation an effort has been made to understand the thermal decomposition and burn rate characteristics of AP as oxidizer and PVC and HTPB as fuel binder in composite solid propellant. The burning rate study has been carried out at ambient and different pressures of 2.068 Mpa, 4.760 Mpa,6.895 Mpa. The mechanism of thermal decomposition of each composition have also been determined by NETZSCH simultaneous thermal analyser, comprising differential scanning calorimeter(DSC) and thermo-gravimetric analyser(TGA). An effort has been made to study the burn rate and decomposition of fuel binder and oxidizer in presence of Fe_2O_3 and also their overall impact on combustion of propellant. 展开更多
关键词 Thermal decomposition BURN rate Thermo-gravimetric analysis AP PVC HTPB Fe2o3
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基于流固耦合的橡胶O形圈老化对密封性能的影响研究 被引量:3
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作者 顾志威 郭飞 +2 位作者 谭桂斌 项冲 张留艳 《润滑与密封》 CAS CSCD 北大核心 2023年第7期21-26,共6页
橡胶O形圈在高温受压的环境下易发生老化并产生泄漏,而最大接触压力和永久压缩变形不足以判定密封系统的密封性能。为了更加精准研究橡胶O形圈在高温受压情况下的老化对密封性能的影响,通过实验获取橡胶O形圈老化后的泄漏率和性能数据,... 橡胶O形圈在高温受压的环境下易发生老化并产生泄漏,而最大接触压力和永久压缩变形不足以判定密封系统的密封性能。为了更加精准研究橡胶O形圈在高温受压情况下的老化对密封性能的影响,通过实验获取橡胶O形圈老化后的泄漏率和性能数据,构建有限元仿真模型,获取不同老化时间下的密封面接触压力,结合流固耦合模型计算出理论泄漏率。通过对比不同老化时间后的橡胶O形圈的实验泄漏率和密封面接触压力评估其密封性能。对比数值模型得到的结果和实验结果,发现理论模型与实际情况一致性较好,验证了该理论模型可为橡胶O形圈的老化行为分析、预测提供指导。 展开更多
关键词 o形圈 老化 泄漏率 最大接触压力
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Effect of temperature on the standard metabolic rates of juvenile and adult Exopalaemon carinicauda 被引量:2
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作者 张成松 李富花 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期381-388,共8页
Ridgetail white prawn (Exopalaemon carinicauda) are of significant economic importance in China where they are widely cultured. However, there is little information on the basic biology of this species. We evaluated... Ridgetail white prawn (Exopalaemon carinicauda) are of significant economic importance in China where they are widely cultured. However, there is little information on the basic biology of this species. We evaluated the effect of temperature (16, 19, 22, 25, 28, 31, and 34℃) on the standard metabolic rates (SMRs) of juvenile and adult E. carinicauda in the laboratory under static conditions. The oxygen consumption rate (OCR), ammonia-N excretion rate (AER), and atornic ratio of oxygen consumed to nitrogen consumed (O:N ratio) of juvenile and adult E. carinicauda were significantly influenced by temperature (P〈0.05). Both the OCR and AER of juveniles increased significantly with increasing temperature from 16 to 34℃, but the maximum OCR for adults was at 31℃. Juvenile shrimp exhibited a higher OCR than the adults from 19 to 34℃. There was no significant difference between the AERs of the two life-stages from 16 to 31 ℃ (P〉0.05). The O:N ratio in juveniles was significantly higher than that in the adults over the entire temperature range (P〈0.05). The temperature coefficient (Q_10) of OCR and AER ranged from 5.03 to 0.86 and 6,30 to 0.85 for the adults, respectively, and from 6,09-1.03 and 3.66-1.80 for the juveniles, respectively. The optimal temperature range for growth of the juvenile and adult shrimp was from 28 to 31℃, based on Q_10 and SMR values. Results from the present study may be used to guide pond culture production ofE. carinicauda. 展开更多
关键词 ammonia-N excretion rate (AER) o:N ratio oxygen consumption rate oCR) temperature temperature coefficient
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Effect of rich R-TiO2 on the rate and cycle properties of Li4Ti5O12 as anode for lithium ion batteries 被引量:3
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作者 Delai Qian Yijie Gu +5 位作者 Shuainan Guo Hongquan Liu Yunbo Chen Juan Wang Guoxuan Ma Chuan Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第5期182-188,共7页
Li4Ti5012 (LTO) with rich R-TiO2 (17.06, 23.69, and 34.42 wt%), namely, R-TiO2@Li4Ti5O12 composites, were synthesized using the hydrothermal method and tetrabutyl titanate (TBT) as the precursor. Rietveld refinement o... Li4Ti5012 (LTO) with rich R-TiO2 (17.06, 23.69, and 34.42 wt%), namely, R-TiO2@Li4Ti5O12 composites, were synthesized using the hydrothermal method and tetrabutyl titanate (TBT) as the precursor. Rietveld refinement of X-ray diffraction (XRD) results show that the proportion of Li occupying 16d sites is extraordinary low and the lattice constants of LTO and R-TiO2 change with the ritanium dioxide content. EIS measurements showed that with in creasing R-TiO2 content, both its charge transfer impedance (Rct) and lithium ion diffusion coefficient (DLi) decreased. The changes of Rct and DLi caused by the increase of titanium dioxide content have synergic-antagonistic effects on the rate and cycle properties of Li4Ti5012. The rate performance is positively related to DLi, while the cycle property is negatively correlated with Rct, indicati ng that the rate performs nee is mainly related to DLi, while Rct more significantly affects the cycle performance. LTO-RT-17.06% exhibited excellent rate properties, especially under a high current density (5.0 C, 132.5 mAh/g) and LTO-RT-34.42% showed superior long-term cycle performance (0.012% capacity loss per cycle) compared to that of LTO-RT-17.06% and LTO-RT-23.69%. 展开更多
关键词 LI4TI5o12 R-Tio2 content rate and CYCLE properties Charge transfer impedance LI-IoN diffusion coefficient
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3D porous V2O5 architectures for high-rate lithium storage 被引量:2
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作者 Qifei Li Dong Chen +3 位作者 Huiteng Tana Xianghua Zhang Xianhong Rui Yan Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期15-21,I0002,共8页
The discovery of novel electrode materials promises to unleash a number of technological advances in lithium-ion batteries.V2O5 is recognized as a high-performance cathode that capitalizes on the rich redox chemistry ... The discovery of novel electrode materials promises to unleash a number of technological advances in lithium-ion batteries.V2O5 is recognized as a high-performance cathode that capitalizes on the rich redox chemistry of vanadium to store lithium.To unlock the full potential of V2O5,nanotechnology solution and rational electrode design are used to imbue V2O5 with high energy and power density by addressing some of their intrinsic disadvantages in macroscopic crystal form.Here,we demonstrate a facile and environmental-friendly method to prepare nanorods-constructed 3D porous V2O5 architectures(3 D-V2O5)in large-scale.The 3D porous architecture is found to be responsible for the enhanced charge transfer kinetics and Li-ion diffusion rate of the 3D-V2O5 electrode.As the result,the 3D-V2O5 surpasses the conventional bulk V2O5 by showing enhanced discharge capacity and rate capability(delivering 154 and 127 m Ah g^-1 at 15 and 20 C,respectively). 展开更多
关键词 Lithium storage V2o5 cathode Porous structure Mass production High rate
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Improved Visible Transparency of SiO_2/ZnO:Al/CeO_2-TiO_2/SiO_2 Multilayer Films with High UV Absorption and Infrared Reflection Rate 被引量:1
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作者 倪佳苗 赵修建 +1 位作者 ZHAO Qingnan ZHENG Mindong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期941-946,共6页
New visible transparent, UV absorption, and high infrared reflection properties have been realized by depositing multilayer Si O2/Zn O: Al/Ce O2-Ti O2/Si O2 films onto glass substrates at low temperature by radio freq... New visible transparent, UV absorption, and high infrared reflection properties have been realized by depositing multilayer Si O2/Zn O: Al/Ce O2-Ti O2/Si O2 films onto glass substrates at low temperature by radio frequency magnetron sputtering. Optimum thickness of Si O2, Zn O: Al(ZAO) and Ce O2-Ti O2(CTO) films were designed with the aid of thin film design software. The degree of antireflection can be controlled by adjusting the thickness and refractive index. The outer Si O2 film can diminish the interference coloring and increase the transparency; the inner Si O2 film improves the adhesion of the coating on the glass substrate and prevents Ca2+, Na+ in the glass substrate from entering the ZAO film. The average transmittance in the visible light range increases by nearly 18%-20%, as compared to double layer ZAO/CTO films. And the films display high infrared reflection rate of above 75% in the wavelength range of 10-25 μm and good UV absorption(> 98%) properties. These systems are easy to produce on a large scale at low cost and exhibit high mechanical and chemical durability. The triple functional films with high UV absorption, antireflective and high infrared reflection rate will adapt to application in flat panel display and architectural coating glass, automotive glass, with diminishing light pollution as well as decreasing eye fatigue and increasing comfort. 展开更多
关键词 Si o2/Zn o:Al /Ce o2-Ti o2/Si o2 TRANSPARENCY high infrared reflection rate ultraviolet absorption optimization
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Large-scale production of holey graphite as high-rate anode for lithium ion batteries 被引量:1
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作者 Feng Xiao Xianghong Chen +4 位作者 Jiakui Zhang Chunmao Huang Tong Hu Bo Hong Jiantie Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第9期122-127,I0004,共7页
Lithium ion batteries(LIBs)have been widely used in portable and smart devices because of their high energy densities,long cycle life and environmental friendliness.In order to meet the evergrowing demand for human-be... Lithium ion batteries(LIBs)have been widely used in portable and smart devices because of their high energy densities,long cycle life and environmental friendliness.In order to meet the evergrowing demand for human-beings utilizing electronic devices,electric vehicles and energy storage grids. 展开更多
关键词 H2o Holey graphite rate capability ANoDE Lithium ion batteries
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Uniform AlF_3 thin layer to improve rate capability of LiNi_(1/3)Co_(1/3) Mn_(1/3)O_2 material for Li-ion batteries 被引量:3
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作者 王海燕 唐爱东 +1 位作者 黄可龙 刘素琴 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期803-808,共6页
LiNi1/3Co1/3Mn1/3O2 was coated with uniform nano-sized AlF3 layer by chemical precipitation method to improve its rate capability.The samples were characterized by X-ray diffractometry (XRD),transmission electron micr... LiNi1/3Co1/3Mn1/3O2 was coated with uniform nano-sized AlF3 layer by chemical precipitation method to improve its rate capability.The samples were characterized by X-ray diffractometry (XRD),transmission electron microscopy (TEM),energy dispersive spectroscopy (EDS),charge-discharge cycling,cyclic voltammetry (CV),and electrochemical impedance spectroscopy (EIS).Uniform coated layer with a thickness of about 3 nm was observed on the surface of LiNi1/3Co1/3Mn1/3O2 particle by TEM.At 0.5C and 2C rates,1.5% (mass fraction) AlF3-coated LiNi1/3Co1/3Mn1/3O2/Li in 2.8-4.3 V versus Li/Li+ after 80 cycles showed less than 3% of capacity fading,while those of the bare one were 16.5% and 45.9%,respectively.At 5C rate,the capacity retention of the coated sample after 50 cycles maintained 91.4% of the initial discharge capacity,while that of the bare one decreased to 52.6%.EIS result showed that a little change of charge transfer resistance of the coated sample resulting from uniform thin AlF3 layer was proposed as the main reason why its rate capability was improved obviously.CV result further indicated a greater reversibility for the electrode processes and better electrochemical performance of AlF3-coated layer. 展开更多
关键词 Li-ion battery LINI1/3Co1/3MN1/3o2 coating uniform thin AlF3 layer rate capability
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Controllable Preparation and Superior Rate Performance of Spinel LiMn2O4 Hollow Microspheresas Cathode Material for Lithium-ion Batteries 被引量:1
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作者 王诗瑶 肖亮 +3 位作者 guo yonglin deng bohua qu deyu xie zhizhong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第3期503-508,共6页
Spinel LiMn2O4 microspheres and hollow microspheres with adjustable wall thickness have been prepared using controllable oxidation of MnCO3 microspheres precursors and following solid reactions with lithium salts. Sca... Spinel LiMn2O4 microspheres and hollow microspheres with adjustable wall thickness have been prepared using controllable oxidation of MnCO3 microspheres precursors and following solid reactions with lithium salts. Scanning electron microscopy (SEM) investigations demonstrate that the microsphere morphology and hollow structure of precursors are inherited. The effect of hollow structure properties of as-prepared LiMn2O4 on their performance as cathode materials for lithium-ion batteries has been studied. Electrochemical performance tests show that LiMn2O4 hollow microspheres with small wall thickness exhibit both superior rate capability and better cycle performance than LiMn2O4 solid microspheres and LiMn2O4 hollow microspheres with thick wall. The LiMn2O4 hollow microspheres with thin wall have discharge capacity of 132.7 mA.h-g^-1 at C/10 (14.8 mA.g^-1) in the first cycle, 94.1% capacity retention at C/10 after 40 cycles and discharge capacity of 116.5 mAh-gq at a high rate of 5C. The apparent lithium-ion diffusion coefficient (Dapp) of as-prepared LiMn2O4 determined by capacity intermittent titration technique (CITT) varies from 10-11 to 10-8.5 cm2.s^-1 showing a regular "W" shape curve plotted with test voltages. The D app of LiMn2O4 hollow microspheres with thin wall has the largest value among all the prepared samples. Both the superior rate capability and cycle stability of LiMn2O4 hollow microspheres with thin wall can be ascribed to the facile ion diffusion in the hollow structures and the robust of hollow structures during repeated cycling. 展开更多
关键词 hollow mierosphere spinel LiMn2o4 spherical MnCo3 rate capability diffusion coefficient
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生物硝化抑制剂对黔西南黄壤硝化作用及N_(2)O排放的影响 被引量:2
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作者 华瑶 陆玉芳 +3 位作者 高维常 祖韦军 施卫明 郭亚利 《土壤》 CAS CSCD 北大核心 2023年第3期512-519,共8页
为探索生物硝化抑制剂对贵州黔西南地区黄壤硝化作用及氧化亚氮(N_(2)O)排放的影响,通过3周的室内培养试验,研究两种生物硝化抑制剂(对羟基苯丙酸甲酯(MHPP)和丁香酸(SA))对黄壤中的无机态氮素含量、氨氧化微生物功能基因以及N_(2)O排... 为探索生物硝化抑制剂对贵州黔西南地区黄壤硝化作用及氧化亚氮(N_(2)O)排放的影响,通过3周的室内培养试验,研究两种生物硝化抑制剂(对羟基苯丙酸甲酯(MHPP)和丁香酸(SA))对黄壤中的无机态氮素含量、氨氧化微生物功能基因以及N_(2)O排放量的影响。结果表明,与对照CK相比,MHPP和SA在黄壤上均能明显抑制硝化作用,对土壤硝化速率的抑制率分别为6%~43%和5%~51%。MHPP和SA均抑制了黄壤氨氧化古菌AOA(12%~22%,27%~41%)与氨氧化细菌AOB(6%~19%,26%~46%)amoA基因的丰度。整个培养期内,黄壤NO_(3)^(-)-N含量与AOB的amoA基因丰度显著正相关,而与AOA的amo A基因丰度无显著相关,表明AOB对黄壤硝化作用起了主导作用。在N_(2)O排放方面,MHPP和SA分别显著抑制了黄壤51%和21%的N_(2)O排放积累量,MHPP的减排效果优于SA。MHPP降低了黄壤N_(2)O排放的峰值,而SA主要延缓了黄壤N_(2)O排放高峰的出现。总之,生物硝化抑制剂MHPP和SA在贵州黔西南黄壤上具有氮肥减施增效的潜力,这为今后烤烟新型绿色专用肥的开发提供了理论依据。 展开更多
关键词 硝化作用 生物硝化抑制剂 黄壤 硝化速率 氨氧化微生物 N_(2)o
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施氮方式与添加脲酶/硝化抑制剂对稻季NH_(3)挥发和N_(2)O排放的影响 被引量:2
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作者 曾科 王书伟 +2 位作者 朱文彬 田玉华 尹斌 《植物营养与肥料学报》 CAS CSCD 北大核心 2023年第2期220-231,共12页
【目的】分析施肥方式及添加脲酶/硝化抑制剂对稻田NH3挥发和N_(2)O排放的影响,基于稻田NH_(3)和N_(2)O减排的效果评价优化施肥措施的可行性。【方法】在太湖地区开展为期两年的稻季田间小区试验,供试脲酶抑制剂为N-丁基硫代磷酰三胺(NB... 【目的】分析施肥方式及添加脲酶/硝化抑制剂对稻田NH3挥发和N_(2)O排放的影响,基于稻田NH_(3)和N_(2)O减排的效果评价优化施肥措施的可行性。【方法】在太湖地区开展为期两年的稻季田间小区试验,供试脲酶抑制剂为N-丁基硫代磷酰三胺(NBPT),硝化抑制剂为对羟基苯丙酸甲酯(MHPP),用量为施氮量的1%。设置6个处理:1)不施氮肥对照(CK);2)表施尿素N 300 kg/hm^(2)(当地常规施肥,CN);3)表施尿素N 225 kg/hm2(RNB);4)尿素N 225 kg/hm^(2),50%表施,50%深施(RND);5)表施尿素N 225 kg/hm^(2)+NBPT+MHPP(RNB+DI);6)尿素N 225 kg/hm^(2)+NBPT+MHPP,50%表施,50%深施(RND+DI)。每次施肥后两周内,用密闭式抽气法监测稻田NH3挥发,在水稻生育期内用静态箱—气相色谱法监测稻田N2O排放。【结果】1) NH_(3)挥发主要发生在每次施氮后7天内,CN、RNB和RNB+DI处理基肥和分蘖肥施用后的NH3挥发量占总挥发量的86.63%~91.76%;稻季N_(2)O排放峰期主要出现在每次施肥后一周内和中期烤田期。2) RNB比CN处理可减少NH3挥发总量29.69%~39.41%和N_(2)O排放总量13.43%~23.37%。3) RND比RNB处理可减少NH_(3)挥发总量53.50%~72.05%和N2O排放总量16.66%~23.43%。4) RNB+DI比RNB处理可减少NH3挥发总量9.57%~22.27%和N_(2)O排放总量8.77%~15.67%。5) RND+DI比CN处理可减少NH3挥发总量76.89%~82.29%和N_(2)O排放总量37.98%~48.71%。【结论】尿素总氮投入减少25%,50%由撒施改为基肥深施,并添加脲酶/硝化抑制剂,可显著减少稻季NH3挥发和N2O总排放,特别是降低NH3挥发的效果更佳;将这3种措施组合集成的RND+DI处理减排效果最佳。该综合集成措施的实际操作性强,为在水稻生产上推广应用提供了技术支撑。 展开更多
关键词 稻季 施氮量 氮肥深施 脲酶抑制剂 硝化抑制剂 NH_(3)挥发 N_(2)o排放
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