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高温热处理对KD-II SiC纤维微观结构与力学性能的影响
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作者 陈静 赵钟倩 +3 位作者 罗景 张松 苟燕子 伍翠兰 《电子显微学报》 北大核心 2026年第1期17-26,共10页
对KD-II纤维高温热暴露过程中微观结构的演变目前仍然缺乏精细的表征和认知。本文针对这一问题对KD-II纤维在高温热暴露过程中微观结构的演变进行了研究,结果表明:当退火温度超过1600℃时,由于β-SiC发生分解,纤维表面会形成石墨壳,石... 对KD-II纤维高温热暴露过程中微观结构的演变目前仍然缺乏精细的表征和认知。本文针对这一问题对KD-II纤维在高温热暴露过程中微观结构的演变进行了研究,结果表明:当退火温度超过1600℃时,由于β-SiC发生分解,纤维表面会形成石墨壳,石墨壳厚度随温度升高而增加,经2200℃氩气中退火1 h后,KD-II纤维已经完全转变为石墨/石墨烯纤维;在纤维分解过程中,母相β-SiC和新相石墨间存在两种界面,一种是{0001}_(Graphite)面与{111}_(β-SiC)界面平行,另一种是{0001}_(Graphite)面垂直于非{111}_(β-SiC)界面。本工作阐明了KD-II纤维在高温热暴露过程中微观结构的演变过程以及与力学性能之间的关系,为高性能SiC纤维的开发提供了宝贵的见解。 展开更多
关键词 KD-ii纤维 微观结构 力学性能 分解界面
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改性凹凸棒土对Cd(II)、Pb(II)的吸附性能
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作者 申保收 孙明奇 +4 位作者 赵纪星 张世玉 黄玖玲 张嘉容 郭忠明 《西北大学学报(自然科学版)》 北大核心 2026年第1期14-24,共11页
凹凸棒土因其优异的离子交换能力和络合特性,广泛应用于重金属吸附材料的研究与开发。本研究通过碱热改性技术,成功制备了一种重金属高效吸附材料(500-ATP-OH),该材料在吸附Cd(II)和Pb(II)方面性能优异。改性后的凹凸棒土通过离子交换作... 凹凸棒土因其优异的离子交换能力和络合特性,广泛应用于重金属吸附材料的研究与开发。本研究通过碱热改性技术,成功制备了一种重金属高效吸附材料(500-ATP-OH),该材料在吸附Cd(II)和Pb(II)方面性能优异。改性后的凹凸棒土通过离子交换作用,实现了晶体结构的优化,增加了材料的比表面积和孔容。研究结果表明,碱热改性处理后的凹凸棒土材料(500-ATP-OH)对Cd(II)的吸附去除率高达99%,吸附容量为123 mg/g;对Pb(II)的吸附去除率更是达到了100%,吸附容量高达331 mg/g。可见,500-ATP-OH作为一种低成本、环境友好型材料,在处理重金属污染水体方面有较大应用潜力。 展开更多
关键词 凹凸棒 碱热改性 CD(ii) PB(ii) 吸附
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Preparation of Ultrafine Copper Powders by Ethanol Solvothermal Method and Properties Study
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作者 XU Yite ZHANG Xiang +6 位作者 HE Junpeng WANG Keke CAO Lei ZHU Qian LIU Baixiong LIU Jianfeng XIONG Shixian 《有色金属(中英文)》 北大核心 2026年第1期31-39,共9页
The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing... The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing agent.Specifically,by exploiting the weak reducing property of ethanol,the copper precursor is first converted to copper oxide and then further reduced to cuprous oxide and pure copper.Such a method can effectively control the morphology and particle size of the copper powder,reduce particle aggregation,and enhance oxidation resistance.It is cost-effective and produces fewer toxic by-products.Spherical copper particles with an average particle size of about 180 nm were obtained.The initial oxidation temperature is approximately 150℃,and the resulting copper powders can be stored stably under ambient conditions for at least 5 months,demonstrating excellent oxidation resistance and thermal stability. 展开更多
关键词 alcohol-solvent heat ultrafine copper powder oxidation resistance thermal stability
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基于改进NSGA-II的直流偏磁抑制装置优化配置研究
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作者 孙胜嘉 赵峰 +1 位作者 周金刑 曹梦茜 《计算机仿真》 2026年第1期417-422,共6页
特高压输电工程的快速建设导致直流偏磁问题多发,对变压器加装限流装置已成为抑制直流偏磁的重要手段。为经济、合理配置限流装置,提出了一种基于改进NSGA-II算法的直流偏磁抑制装置优化配置方法。为实现电阻、电容限流装置在优化配置... 特高压输电工程的快速建设导致直流偏磁问题多发,对变压器加装限流装置已成为抑制直流偏磁的重要手段。为经济、合理配置限流装置,提出了一种基于改进NSGA-II算法的直流偏磁抑制装置优化配置方法。为实现电阻、电容限流装置在优化配置问题中的准确映射,在NSGA-II算法中引入多值编码环节;为提高NSGA-II算法的全局寻优能力和配置优化问题求解速度,采用基于高效非支配排序的种群进化策略,降低了算法时间与空间复杂度。利用提出的改进NSGA-II算法对±800kV宾金直流受端电网区域进行直流偏磁抑制装置优化配置,结果表明该算法能够快速、有效地实现电网区域内各个变电站的直流偏磁抑制装置的最优配置。 展开更多
关键词 改进非支配排序遗传算法ii 多目标优化 直流偏磁
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Advances in organoelectrochemical copper-catalyzed reactions
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作者 Pan Zhou Ting Zou +2 位作者 Hong-Jian Song Yu-Xiu Liu Qing-Min Wang 《Chinese Chemical Letters》 2026年第1期25-38,共14页
The combination of electrochemistry and metal catalysts has been a popular research topic in the field of organic synthesis due to the abundance and controllable valence states of transition metals,where electron tran... The combination of electrochemistry and metal catalysts has been a popular research topic in the field of organic synthesis due to the abundance and controllable valence states of transition metals,where electron transfer at the electrode produces catalysts with more valence states.Among these transition metal catalysts,electrochemical conversions catalyzed by inexpensive copper metals have received considerable attention.This article systematically investigated this field and reviewed the electrochemical copper catalytic methods applied in organic synthesis from the different activation modes of substrates,which can be broadly classified into the functionalization of C=C bonds,C-H bond activation,C-C and C-X bond activation,and so on. 展开更多
关键词 ELECTROCHEMISTRY Transition metal catalysis copper catalysis copper electrocatalysis
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Dissolution kinetics of a low-grade oxide-sulfide copper ore with high silica content:Laboratory studies and statistical modeling
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作者 Hiva Farhadi Faramarz Doulati Ardejani +5 位作者 Sied Ziaedin Shafaei Tonkaboni Soroush Maghsoudy Roya Kafi Helia Tafakori Christoph Butscher Reza Taherdangkoo 《Acta Geochimica》 2026年第1期111-131,共21页
In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics... In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics.Given copper's extensive industrial applications,sustainable recovery from low-grade ores is critical.Five key parameters-acid concentration,leaching time,particle size,temperature,and solids percentage-were identified as major influences on copper recovery.The results revealed that leaching time and solids percentage,along with interactions between temperature-time and temperature-solids percentage,had the most significant effects.Optimal conditions for 80% copper recovery while minimizing iron recovery below 3% included an acid concentration of 1.21 mol L^(-1),a leaching time of 108 min,a particle size of 438μm,a temperature of 45℃,and a solids percentage of 18.2%.Leaching kinetics were analyzed using shrinking core models,with the Dickinson model best describing the process,showing an activation energy of 32.63 kJ mol^(-1),indicative of mixed diffusion and chemical reaction control.The final kinetic model effectively predicted the influence of key parameters.These findings highlight the importance of optimizing process variables and selecting suitable kinetic models to enhance extraction efficiency,reduce costs,and improve sustainability in copper recovery. 展开更多
关键词 Oxide-sulfi de ore Response surface methodology Kinetic analysis Miduk copper mine Shrinking core model copper leaching
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Effect of hydrogen sulfide on reductive leaching of chalcopyrite by copper
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作者 Xin SUN Rui LIAO +5 位作者 Zu-chao PAN Yi-sheng ZHANG Mao-xin HONG Yan-sheng ZHANG Jun WANG Guan-zhou QIU 《Transactions of Nonferrous Metals Society of China》 2026年第1期287-297,共11页
A series of leaching and electrochemical experiments were conducted to elucidate the critical role of hydrogen sulfide(H_(2)S)in copper-driven reduction of chalcopyrite.Results demonstrate that in the absence of H_(2)... A series of leaching and electrochemical experiments were conducted to elucidate the critical role of hydrogen sulfide(H_(2)S)in copper-driven reduction of chalcopyrite.Results demonstrate that in the absence of H_(2)S,metallic copper converts chalcopyrite into bornite(Cu_(5)FeS_(4)).However,the introduction of H_(2)S promotes the formation of chalcocite(Cu_(2)S)by altering the oxidation pathway of copper.Electrochemical analysis demonstrates that the presence of H₂S significantly reduces the corrosion potential of copper from 0.251 to−0.223 V(vs SHE),reaching the threshold necessary for the formation of Cu_(2)S.Nevertheless,excessive H_(2)S triggers sulfate reduction via the reaction of 8Cu+H_(2)SO_(4)+3H_(2)S=4Cu_(2)S+4H_(2)O(ΔG=−519.429 kJ/mol at 50℃),leading to inefficient copper utilization. 展开更多
关键词 chalcopyrite reduction copper hydrogen sulfide CHALCOCITE
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In situ Raman spectroscopic investigation of copper speciation in hydrothermal fluids at temperatures up to 300℃
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作者 Zhenglong Wang Linbo Shang +6 位作者 I-Ming Chou Chen Chen Yunhe Zhou Jianguo Li Ziqi Jiang Xinwei Gao Ye Wan 《Acta Geochimica》 2026年第1期142-154,共13页
The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesi... The formation of copper deposits is closely related to hydrothermal processes.Understanding the migration of copper in hydrothermal fluids aids in reconstructing mineralization processes and deciphering deposit genesis.Copper primarily exists as Cu^(+)and Cu^(2+)in hydrothermal solutions,with redox conditions governing their interconversion.In chloride-rich geological fluids,Cu-Cl complexes are considered critical for copper transport.However,the specific types and valence transitions of Cu-Cl complexes under varying hydrothermal conditions remain poorly understood.This study employed in situ Raman spectroscopy to systematically analyze Cu+HCl and CuCl_(2)+K_(2)S_(2)O_(3)/H_(2) systems under saturated vapor pressure at 25-300℃,elucidating the effects of temperature,Cl^(-)concentration,and redox conditions on copper speciation.In the Cu^(+)HCl system,copper dissolved as monovalent Cu-Cl complexes.At high temperatures(>200℃),[CuCl_(2)]^(-)is the dominated species,whereas[CuCl_(3)]^(2-)becomes prevalent at lower temperatures and higher HCl concentrations.For the Cu^(2+)-Cl system,the dominant species transitioned from[Cu(H_(2)O)n]^(2+)(<50℃)to[CuCl_(4)]^(2-)(100℃)and further to[CuCl]^(+)and[CuCl_(2)]^(0) at 300℃.The introduction of reducing agents(K_(2)S_(2)O_(3)/H_(2))facilitated Cu^(2+)→Cu^(+)reduction,thereby stabilizing Cu^(+)-Cl complexes and inducing partial copper precipitation.The behavior of copper in chloriderich hydrothermal fluids observed in this study indicates that high-temperature oxidizing fluids facilitate Cu mobilization,while cooling and redox changes promote deposition and ore minerals formation. 展开更多
关键词 Raman spectroscopy In situ analysis Hydrothermal fluids copper Transport mechanism
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Zhu Bingren:Copper Artist Extraordinaire
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作者 NILS BERGEMANN 《China Today》 2026年第2期73-75,共3页
At 82,master craftsman Zhu Bingren,China’s preeminent copper artist,continues to dynamically evolve his ancient heritage,proving that true preservation lies in innovation and bringing tradition into the contemporary ... At 82,master craftsman Zhu Bingren,China’s preeminent copper artist,continues to dynamically evolve his ancient heritage,proving that true preservation lies in innovation and bringing tradition into the contemporary world.THE copper art should not be confined to display cases,believes artist Zhu Bingren.From living rooms to fashion runways,and from the Great Wall in Beijing to the Louvre in Paris,the Chinese master craftsman brings his metal creations to life in diverse settings. 展开更多
关键词 innovation master craftsman TRADITION copper art contemporary world Zhu Bingren
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Effect of fluoride roasting on copper species transformation on chrysocolla surfaces and its role in enhanced sulfidation flotation
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作者 Yingqiang Ma Xin Huang +5 位作者 Yafeng Fu Zhenguo Song Sen Luo Shuanglin Zheng Feng Rao Wanzhong Yin 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期165-176,共12页
It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla we... It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla were investigated,its impact on sulfidation flotation was explored,and the mechanisms involved in both fluoride roasting and sulfidation flotation were discussed.With CaF_(2)as the roasting reagent,Na_(2)S·9H_(2)O as the sulfidation reagent,and sodium butyl xanthate(NaBX)as the collector,the results of the flotation experiments showed that fluoride roasting improved the floatability of chrysocolla,and the recovery rate increased from 16.87%to 82.74%.X-ray diffraction analysis revealed that after fluoride roasting,approximately all the Cu on the chrysocolla surface was exposed in the form of CuO,which could provide a basis for subsequent sulfidation flotation.The microscopy and elemental analyses revealed that large quantities of"pagoda-like"grains were observed on the sulfidation surface of the fluoride-roasted chrysocolla,indicating high crystallinity particles of copper sulfide.This suggests that the effect of sulfide formation on the chrysocolla surface was more pronounced.X-ray photoelectron spectroscopy revealed that fluoride roasting increased the relative contents of sulfur and copper on the surface and that both the Cu~+and polysulfide fractions on the surface of the minerals increased.This enhances the effect of sulfidation,which is conducive to flotation recovery.Therefore,fluoride roasting improved the effect of copper species transformation and sulfidation on the surface of chysocolla,promoted the adsorption of collectors,and improved the recovery of chrysocolla from sulfidation flotation. 展开更多
关键词 sulfidation flotation CHRYSOCOLLA fluoride roasting copper species transformation enhanced sulfidation
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自锁托槽与传统金属托槽矫治青少年安氏II类1分类错颌畸形的治疗时间及牙根吸收对比分析
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作者 黄丽影 《中文科技期刊数据库(文摘版)医药卫生》 2026年第1期053-056,共4页
探讨自锁托槽与传统金属托槽矫治青少年安氏II类1分类错颌畸形的临床效果差异。方法 回顾性分析崇左市人民医院2022年1月至2025年1月收治的60例安氏II类1分类错颌畸形青少年患者资料,按矫治器类型分为自锁托槽组和传统托槽组各30例,比... 探讨自锁托槽与传统金属托槽矫治青少年安氏II类1分类错颌畸形的临床效果差异。方法 回顾性分析崇左市人民医院2022年1月至2025年1月收治的60例安氏II类1分类错颌畸形青少年患者资料,按矫治器类型分为自锁托槽组和传统托槽组各30例,比较两组治疗总时间、牙根吸收程度、牙齿移动效率及托槽脱落情况。结果 自锁托槽组总矫治时间(18.42±2.31)月,显著短于传统托槽组(22.68±2.85)月(t=6.342,P<0.001);自锁托槽组上颌中切牙根吸收量(0.82±0.21)mm,低于传统托槽组(1.38±0.34)mm(t=7.648,P<0.001);自锁托槽组排齐整平期牙齿移动速率(1.42±0.18)mm/月,高于传统托槽组(1.08±0.15)mm/月(t=7.943,P<0.001);自锁托槽组托槽脱落率6.67%,低于传统托槽组20.00%(x²=8.571,P=0.003)。结论 自锁托槽矫治青少年安氏II类1分类错颌畸形可缩短治疗时间,减少牙根吸收,提高矫治效率。 展开更多
关键词 自锁托槽 传统金属托槽 安氏ii类1分类错颌畸形 治疗时间 牙根吸收
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基于MILP和NSGA-II的多类型储能协同调度优化
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作者 冯春贤 王文学 +4 位作者 王一峰 张飞飞 袁龙 范志昊 陈衡 《热力发电》 北大核心 2026年第2期180-192,共13页
【目的】为应对高比例新能源接入电网对灵活性与经济性的需求,提出一种面向峰谷电价与新能源波动的多类型储能协同调度优化模型及调度策略。【方法】基于混合整数线性规划算法(MILP)与非支配排序多目标遗传算法(NSGA-II),构建以系统总... 【目的】为应对高比例新能源接入电网对灵活性与经济性的需求,提出一种面向峰谷电价与新能源波动的多类型储能协同调度优化模型及调度策略。【方法】基于混合整数线性规划算法(MILP)与非支配排序多目标遗传算法(NSGA-II),构建以系统总成本最低和新能源消纳率最高为双目标的优化调度模型,并通过河北地区不同季节典型日的负荷与风光出力数据验证模型的经济性与消纳效果。【结果】结果表明:该模型具有较好的鲁棒性,能够适应风光与负荷波动;春季最佳储能出力为3 000 MW,夏季、秋季、冬季均为2 000 MW,各季节特征日风光消纳率均保持在85%以上,系统总成本控制在15 000元水平。【结论】研究通过融合多季节场景、多类型储能及多目标优化,实现了经济性与新能源消纳水平的协同提升,有效增强了电网灵活性并降低了弃风弃光率。 展开更多
关键词 多类型储能 优化调度 MILP算法 NSGA-ii算法 新能源消纳
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约恩·福瑟《另一个名字:七部曲I-II》的记忆与自我
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作者 武姨虹 孔瑞 《语言与文化研究》 2026年第1期208-211,共4页
2023年诺贝尔文学奖得主约恩·福瑟新近出版的小说《另一个名字:七部曲I-II》的记忆书写不仅是叙事手法,更揭示了自我身份建构主题。本文基于记忆理论,探析“既视”记忆中的自我危机,记忆之场的自我追寻,以及通过自传体记忆建构自... 2023年诺贝尔文学奖得主约恩·福瑟新近出版的小说《另一个名字:七部曲I-II》的记忆书写不仅是叙事手法,更揭示了自我身份建构主题。本文基于记忆理论,探析“既视”记忆中的自我危机,记忆之场的自我追寻,以及通过自传体记忆建构自我。记忆深入人类心灵深处,呈现了自我在非线性时间中的流动与重构,也揭示了人类对存在本质的永恒追问。 展开更多
关键词 约恩·福瑟 《另一个名字:七部曲I-ii 记忆 自我
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EVAR术后II型内漏的临床管理研究进展
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作者 王璐 段青 《临床医学进展》 2026年第2期2385-2392,共8页
目的:综述主动脉瘤腔内修复术(EVAR)后II型内漏(T2EL)临床管理策略的最近研究进展。方法:系统梳理T2EL相关的流行病学特征与自然病程、当前治疗争议,重点对经动脉栓塞(TAE)、直接瘤囊穿刺(DSP)、经腔静脉栓塞(TCE)等介入技术的优劣进行... 目的:综述主动脉瘤腔内修复术(EVAR)后II型内漏(T2EL)临床管理策略的最近研究进展。方法:系统梳理T2EL相关的流行病学特征与自然病程、当前治疗争议,重点对经动脉栓塞(TAE)、直接瘤囊穿刺(DSP)、经腔静脉栓塞(TCE)等介入技术的优劣进行对比,以及讨论弹簧圈、Onyx液体栓塞剂及新型聚合物等栓塞材料的治疗疗效,同时探讨腹腔镜结扎、动脉瘤缝合术及开放手术转换等外科干预方案的可行性与安全性。结果:目前多数研究表明T2EL是EVAR术后常见并发症,多数呈良性病程,对不伴瘤囊增大的孤立性T2EL建议保守观察。但当瘤囊持续扩张时,需考虑积极干预。证据表明,DSP对于TAE多次失败的病例是一种可作为选择的方案。除此之外,对于介入治疗失败的高危患者,微创外科手术及开放手术转流是有效的补救措施。结论:实际临床医生在EVAR术后T2EL的临床决策中,需权衡患者的个体化选择保守观察或积极干预。未来研究应致力于通过前瞻性试验明确干预阈值,并评估新型材料与技术在复杂内漏管理中的远期效益。 展开更多
关键词 腹主动脉瘤 血管内修复术 ii型内漏 经动脉栓塞 直接瘤囊穿刺 ONYX栓塞
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基于改进NSGA-II算法的钢管混凝土拱桥优化研究
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作者 汤杰豪 余钱华 《工程建设》 2026年第1期39-45,共7页
为了有效解决大跨径钢管混凝土拱桥多目标优化设计中解集收敛性不足、工程实用性受限的难题,以涂乍河特大桥为工程背景,通过提出一种融合自适应交叉变异算子与动态约束处理机制的改进NSGA-Ⅱ算法,以实现承载力、轻量化与经济性的协同优... 为了有效解决大跨径钢管混凝土拱桥多目标优化设计中解集收敛性不足、工程实用性受限的难题,以涂乍河特大桥为工程背景,通过提出一种融合自适应交叉变异算子与动态约束处理机制的改进NSGA-Ⅱ算法,以实现承载力、轻量化与经济性的协同优化。优化结果表明:主拱圈重量降低12.2%,承载力安全系数提升至1.83;主梁跨中正弯矩减少14.5%,活载挠度降幅达17.8%;综合造价较原方案节约8%。进一步分析算法性能可知,改进NSGA-Ⅱ的Pareto解集收敛性与分布性显著提升(超体积指标HV较传统算法提高22%),且所有优化方案均严格满足规范要求。本文成果可为复杂拱桥结构的多目标优化设计提供理论支撑与工程实践参考。 展开更多
关键词 钢管混凝土拱桥 多目标优化设计 承载力 轻量化 经济性 改进NSGA-Ⅱ算法
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A^(*)与NSGA-II融合的船舶气象航线多目标规划方法 被引量:2
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作者 李元奎 索基源 +3 位作者 于东冶 张新宇 杨放 杨雪锋 《中国舰船研究》 北大核心 2025年第3期288-295,共8页
[目的]面向我国智能航运和气象导航国产化的发展要求,提出一种基于A^(*)与非支配排序遗传算法(NSGA-II)融合的船舶多目标航线规划方法,以适应复杂多样的远洋航行任务。[方法]通过将A^(*)算法引入至NSGA-II中引导搜索方向加快算法收敛速... [目的]面向我国智能航运和气象导航国产化的发展要求,提出一种基于A^(*)与非支配排序遗传算法(NSGA-II)融合的船舶多目标航线规划方法,以适应复杂多样的远洋航行任务。[方法]通过将A^(*)算法引入至NSGA-II中引导搜索方向加快算法收敛速度,然后通过构建环境数据模型和目标函数,采用跨太平洋航线对模型和算法进行仿真验证。[结果]仿真结果表明:设计的模型和算法可求解得到分布均匀、多样化的Pareto最优航线解集,所有航线均可以顺利躲避大风浪区域,且可根据决策者需求选择船舶最适航线。[结论]所提方法可用于多约束条件下的船舶远洋航线优化,求解符合航次目标的航线,从而降低营运成本、提高航运效率,对船舶气象导航和未来船舶智能航行具有一定的支撑作用。 展开更多
关键词 气象航线 多目标优化 A^(*)算法 NSGA-ii 智能航行 遗传算法
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Synthesis, Structure and Fluorescence of a Copper(II) Complex [Cu_2(bipy)_2(Hpht)_2Cl](Hpht)(bipy=2,2'-Bipyridine,H_2pht=o-Phthalic Acid) 被引量:4
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作者 李强 郑发鲲 +3 位作者 蔡丽珍 陈文通 郭国聪 黄锦顺 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期354-358,共5页
The title complex [Cu2(bipy)2(Hpht)2Cl](Hpht) (bipy = 2,2?-bipyridine, H2pht = o-phthalic acid) has been synthesized in the NaOH aqueous solution of CuCl2, Gd(NO3)3, bipy and H2pht, and its crystal structure was det... The title complex [Cu2(bipy)2(Hpht)2Cl](Hpht) (bipy = 2,2?-bipyridine, H2pht = o-phthalic acid) has been synthesized in the NaOH aqueous solution of CuCl2, Gd(NO3)3, bipy and H2pht, and its crystal structure was determined by single-crystal X-ray diffraction method. It crys- tallizes in triclinic, space group P1, C44H31ClCu2N4O12, Mr = 970.26, a = 8.175(2), b = 16.254(4), c = 16.946(4) ?, α = 62.966(6), β = 84.833(8), γ = 84.348(8)°, V = 1993.4(8) ?3, Z = 2, Dc = 1.616 g/cm3, F(000) = 988 and μ = 1.207 mm-1. The final R = 0.0429 and wR = 0.0843 for 5682 observed reflections with I > 2σ(I). Each copper(II) atom displays a distorted square-pyramidal geometry with two nitrogen atoms of one chelate 2,2?-bipy molecule, two oxygen atoms from two different bridging carboxylate groups of Hpht- and one bridging chloride atom occupying the apical position. The two copper(II) atoms are connected by a μ2-Cl atom and two bridging Hpht- ligands in a syn-syn coordination mode to form an isolated dinuclear unit. The molecular structure is extended to a one-dimensional wavy chain through hydrogen bonds. The title complex exhibits blue fluorescent emission at 443 nm (λex = 372 nm) in the solid state at room temperature. 展开更多
关键词 copper(ii) complex crystal structure SYNTHESIS LUMINESCENCE
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Synthesis and Crystal Structure of Tri(4-(3-hydroxy2-ethyl-4-pyridinone-1-yl)-aniline Condensation Salicylaldehydato) Monohydratotricopper(II)Dimethylformamide Monohydrate Solvate 被引量:2
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作者 LUZai-Sheng NIUDe-Zhong +1 位作者 TUShu-Jiang CHENJiu-Tong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期681-686,共6页
The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H1... The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H15N2O3)3(H2O)]DMFH2O. The coordi- nation sphere about each copper ion in the complex consists of two oxygen atoms from hydroxylpyridinone moiety of one ligand and one oxygen and one nitrogen atoms from salicyladehyde Schiff-base moiety of another ligand arranged in a slightly distorted square planar geometry. Among the three copper ions, one (Cu(2)) is coordinated by the other oxygen atom of water molecule on the fifth coordinate position to form a distorted square pyramid geometry. The crystal is of monoclinic, space group P21/c with a = 12.9202(5), b = 27.197(1), c = 17.0116(7) ? b = 100.588(1), V = 5875.9(4) 3, Z = 4, C63H57N7O12Cu3, Mr = 1294.78, Dc = 1.464 g/cm3, m = 1.146 mm-1, F(000) = 2668, R = 0.0784 and wR = 0.1546 for 6926 observed reflections with I > 2s(I). The differences of coordinate bond lengths are observed between anhydrous and hydrous units: in the former unit, the average bond lengths are 1.978 ?for CuN (azomethine), 1.883 ?for CuO (phenolic) in Schiff-base moiety, 1.959 ?for CuO (keto), and 1.919 ?for CuO (hydroxy) in hydroxypyridinone moiety; while those in the latter are longer with the following corresponding values: 1.985(5), 1.908(5), 1.993(5) and 1.919(4) ? respectively. The Cu(2)O (water) bond length is 2.375(6) ? 展开更多
关键词 copper(ii) complex 4-(3-hydroxy-2-ethyl-4-pyridinone-1-yl)-aniline salicylaldehyde Schiff-base crystal structure
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Adsorption of Lead(II),Copper(II) on tourmaline from Altai mine in China's Sinkiang 被引量:2
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作者 HE Dengliang YIN Guangfu +3 位作者 DONG Faqin ZHANG Wei BIANQingquan SI yunxiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期423-429,共7页
Tourmaline from Altai mine in China's Sinkiang was used to remove lead (II), copper (II) from aqueous solution. The results demonstrate that tourmaline contains Na(Mg,V)3AI6(BO3)3Si6Ols (OH)4, NaFe3AI6(BO3... Tourmaline from Altai mine in China's Sinkiang was used to remove lead (II), copper (II) from aqueous solution. The results demonstrate that tourmaline contains Na(Mg,V)3AI6(BO3)3Si6Ols (OH)4, NaFe3AI6(BO3)3Si6Ols(OH)4. The data show that Tourmaline from Altai mine in China's Sinkiang can be used natural adsorbent for lead (II), copper (II).It is observed that the adsorption data fitted to the Langmuir isotherm. Furthermore, both Pb (II) and Cu (II) absorbed by tourmaline and tourmaline were characterized by X-ray diffraction, Laser Raman Spectrum, Fourier transform infrared spectroscopy, X-ray energy dispersive spectrometer, Transmission electron microscopy and Zeta potential. 展开更多
关键词 TOURMALINE lead ii copper ii ADSORPTION
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Synthesis and Structure of bis(μ-2-aminopyridine N-oxide)-bis[dichlorocopper(II)] 被引量:1
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作者 牛德绅 路再生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期270-273,共4页
The complex [Cu2(apo)4Cl4]·2H2O (apo=2-aminopyridine N-oxide) was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound (Cu2C20H28Cl4N8O6). The coordination geometry about e... The complex [Cu2(apo)4Cl4]·2H2O (apo=2-aminopyridine N-oxide) was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound (Cu2C20H28Cl4N8O6). The coordination geometry about each copper atom is best described as a distorted square pyramid. The compound [Cu2(apo)4Cl4]·2H2O belongs to the triclinic system with space group P, lattice constants: a = 7.8550(7), b = 8.5378(7), c = 12.082(1) ?, α = 72.807(1), β = 77.641(1), γ = 70.800(1)(, V =724.85(11) ?3, Z=1, Mr =745.38, Dc=1.708 g/cm3, μ =1.886mm-1, F(000) =378, R=0.0359, wR2=0.0884 for 2220 reflections with I >2σ(I). The distances between Cu(II) and O atoms are in the range from 1.934(2) to 2.042(2)?. The distance between two copper atoms Cu-Cu(A) is 3.2978(8) ?. The distances of Cu-Cl(1) and Cu-Cl(2) are 2.2322(9), 2.5095(10) ?, respectively. There is no evident hydrogen bond between N and Cl. 展开更多
关键词 crystal structure copper(ii) 2-aminopyridine N-oxide binuclear complex
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