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Cu掺杂及缺陷共存对ZnO光催化影响的理论研究
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作者 张海峰 赵晋忠 +1 位作者 伊思静 卢士香 《原子与分子物理学报》 CAS 北大核心 2025年第2期24-32,共9页
采用密度泛函理论研究了Cu掺杂及缺陷共存对ZnO光催化性能的影响.计算时考虑了富O和贫O两种掺杂条件.研究结果表明富O条件有利于Cu的掺杂,贫O条件则产生抑制作用.当Cu掺杂浓度较低时,不论在何种掺杂条件下,Cu的主要掺杂方式均为Cu_(Zn)... 采用密度泛函理论研究了Cu掺杂及缺陷共存对ZnO光催化性能的影响.计算时考虑了富O和贫O两种掺杂条件.研究结果表明富O条件有利于Cu的掺杂,贫O条件则产生抑制作用.当Cu掺杂浓度较低时,不论在何种掺杂条件下,Cu的主要掺杂方式均为Cu_(Zn)型.当Cu掺杂浓度较高时,富O条件下以Cu_(Zn)-Cu_(Zn)型掺杂方式为主,贫O条件下Cu_(Zn)-Cu_(Zn)和Cu_(Zn)-Cui这两种掺杂方式都有可能出现.富O条件下Cu掺杂会促进V_(Zn)和O_(i)缺陷的产生,且引入的V_(Zn)和O_(i)缺陷趋向于距离Cu原子最近.Cu掺杂可有效降低ZnO的带隙宽度,且随着掺杂浓度的增加,相应模型的带隙宽度会继续降低.V_(Zn)、O_(i)和V_(O)缺陷共存使相应模型的带隙宽度有所增加.Cu掺杂及V_(Zn)、O_(i)、V_(O)缺陷共存使模型对可见光发生响应,扩展了模型对太阳光的吸收范围.对于Cu掺杂模型,富O条件下Cu_(Zn)-Cu_(Zn)是有利的光催化模型.对于缺陷共存模型,富O条件下Cu_(Zn)-Cu_(Zn)-V_(Zn)是有利的光催化模型,其次是Cu_(Zn)-V_(Zn)和Cu_(Zn)-O_(i),贫O条件下Cu_(Zn)-V_(O)是有利的光催化模型. 展开更多
关键词 ZNO cu掺杂 缺陷共存 密度泛函理论 光催化
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Two novel Cu(Ⅰ)complexes based on diimide and bisphosphine ligands:synthesis,crystal structure and spectroscopic properties
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作者 FAN Sijie ZHAO Jingtong +6 位作者 ZHANG Shuai ZHANG Yuxin SUN Zhenzhou LI Zhongfeng HAN Hongliang XIN Xiulan JIN Qionghua 《黑龙江大学自然科学学报》 CAS 2024年第5期526-535,共10页
Two Cu(Ⅰ)complexes[Cu(Bphen)(dppBz)]ClO_(4)·2CH_(3)OH(1)and[Cu_(2)(Bphen)_(2)(dpppda)]BF_(4)(2){Bphen=4,7-diphenyl-1,10-phenanthroline,dppBz=1,2-Bis(diphenylphosphino)benzene,dpppda=N1,N1,N4,N4-tetrakis[(dipheny... Two Cu(Ⅰ)complexes[Cu(Bphen)(dppBz)]ClO_(4)·2CH_(3)OH(1)and[Cu_(2)(Bphen)_(2)(dpppda)]BF_(4)(2){Bphen=4,7-diphenyl-1,10-phenanthroline,dppBz=1,2-Bis(diphenylphosphino)benzene,dpppda=N1,N1,N4,N4-tetrakis[(diphenylphosphino)methyl]-1,4-benzenediamin}were synthesized using a one-pot method.X-ray crystallography was used to elucidate their crystal structures and photophysical properties.A series of characterization tests including elemental analysis,NMR,FT-IR,UV-Vis absorption spectroscopy,fluorescence spectroscopy,thermal gravimetric analysis and terahertz time-domain spectroscopy(THz-TDS)were used to further investigate their properties.The results show that complex 1 structure is mononuclear containing two solvent molecules per unit cell,while complex 2 structure is binuclear containing two metal centers per unit cell.According to photophysical properties and density functional theory(DFT)calculations,their luminescence properties can be attributed to metal-to-ligand charge transfer(MLCT).Both complexes have a unique stability,which is confirmed by thermal gravimetric analysis. 展开更多
关键词 cu(Ⅰ)complex crystal structure fluorescence spectrum terahertz time-domain spectroscopy
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Squeeze and Excitation Convolution with Shortcut for Complex Plasma Image Recognition
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作者 Baoxia Li Wenzhuo Chen +5 位作者 Xiaojiang Tang Shaohuang Bian Yang Liu Junwei Guo Dan Zhang Feng Huang 《Computers, Materials & Continua》 SCIE EI 2024年第8期2221-2236,共16页
Complex plasma widely exists in thin film deposition,material surface modification,and waste gas treatment in industrial plasma processes.During complex plasma discharge,the configuration,distribution,and size of part... Complex plasma widely exists in thin film deposition,material surface modification,and waste gas treatment in industrial plasma processes.During complex plasma discharge,the configuration,distribution,and size of particles,as well as the discharge glow,strongly depend on discharge parameters.However,traditional manual diagnosis methods for recognizing discharge parameters from discharge images are complicated to operate with low accuracy,time-consuming and high requirement of instruments.To solve these problems,by combining the two mechanisms of attention mechanism(strengthening the extraction of the channel feature)and shortcut connection(enabling the input information to be directly transmitted to deep networks and avoiding the disappearance or explosion of gradients),the network of squeeze and excitation convolution with shortcut(SECS)for complex plasma image recognition is proposed to effectively improve the model performance.The results show that the accuracy,precision,recall and F1-Score of our model are superior to other models in complex plasma image recognition,and the recognition accuracy reaches 97.38%.Moreover,the recognition accuracy for the Flowers and Chest X-ray publicly available data sets reaches 97.85%and 98.65%,respectively,and our model has robustness.This study shows that the proposed model provides a new method for the diagnosis of complex plasma images and also provides technical support for the application of plasma in industrial production. 展开更多
关键词 Image recognition complex plasmas deep learning
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Scale, Complexity, and Cybersecurity Risk Management
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作者 Christopher Briscoe Carl Young 《Journal of Information Security》 2024年第4期524-544,共21页
Elementary information theory is used to model cybersecurity complexity, where the model assumes that security risk management is a binomial stochastic process. Complexity is shown to increase exponentially with the n... Elementary information theory is used to model cybersecurity complexity, where the model assumes that security risk management is a binomial stochastic process. Complexity is shown to increase exponentially with the number of vulnerabilities in combination with security risk management entropy. However, vulnerabilities can be either local or non-local, where the former is confined to networked elements and the latter results from interactions between elements. Furthermore, interactions involve multiple methods of communication, where each method can contain vulnerabilities specific to that method. Importantly, the number of possible interactions scales quadratically with the number of elements in standard network topologies. Minimizing these interactions can significantly reduce the number of vulnerabilities and the accompanying complexity. Two network configurations that yield sub-quadratic and linear scaling relations are presented. 展开更多
关键词 complexITY CYBERSEcuRITY SCALE Scaling Relations Stochastic Linear Non-Linear MACROSCOPIC Organized complexity Disorganized complexity
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Cultural Complex Design from the Perspective of Urban Renewal: A Case Study of Incheon Geomdan Cultural Complex in South Korea
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作者 YANG Peizhe LI Daoyong SUN Ziin 《Journal of Landscape Research》 2024年第3期88-90,共3页
Urban development should rely on the form of architecture,and incorporating urban planning concepts into architectural design can better assist urban construction.Taking the design of Incheon Geomdan Cultural Complex ... Urban development should rely on the form of architecture,and incorporating urban planning concepts into architectural design can better assist urban construction.Taking the design of Incheon Geomdan Cultural Complex in South Korea as an example,this paper analyzes how to reflect urban planning elements in architectural design,and studies the role and value of cultural complex architecture in urban development from multiple perspectives such as culture,ecological environment,and public space.It hopes to gain more research and design ideas to promote the development of cultural industries in the region,leverage the advantages of regional cultural formats,and create new cultural settlements in cities. 展开更多
关键词 Urban renewal cultural complex DEVELOPMENT ECOLOGY
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Lymphovenous anastomosis and complex decongestive therapy for severe deformed lymphedema with recurrent infection:A case report
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作者 He-Jun Wang Qing-Qing He +2 位作者 Chang-Rui Liu Ying-Ying Wang Xun-Wei Liu 《World Journal of Clinical Cases》 SCIE 2024年第22期5159-5167,共9页
BACKGROUND Lower extremity lymphedema is a common complication following treatment for gynecological malignancies.Its incidence rate can reach up to 70%,affecting~20 million people worldwide.However,specialized treatm... BACKGROUND Lower extremity lymphedema is a common complication following treatment for gynecological malignancies.Its incidence rate can reach up to 70%,affecting~20 million people worldwide.However,specialized treatment centers are scarce,and there is a lack of consensus on treatment approaches.Furthermore,there are even fewer reports on the systematic and effective treatment of severe lymphedema with malformations.Effective management of this condition remains a significant challenge for clinicians.CASE SUMMARY A 40-year-old woman developed bilateral leg swelling 6 years after receiving treatment for endometrial cancer.Since August 2018,she experienced>30 episodes of lymphangitis.Upon presentation,she exhibited bilateral leg swelling and deformation,with four large swellings in the posterior thigh that impeded movement,and pain in the limbs.Skin manifestations included lichenoid lesions and features of deep sclerosis.Radionuclide lymphoscintigraphy confirmed the diagnosis of lower limb lymphedema.After 6 mo of complex decongestive therapy(CDT)and three lymphaticovenous anastomosis(LVA)treatments,the patient lost 49 kg in weight.She also experienced a maximum circumference reduction of 35.2 cm in the left lower limb and 37.5 cm in the right lower limb.The leg pain disappeared,her swelling significantly decreased,and she regained the ability to walk,cycle,and run normally.CONCLUSION The combined application of CDT and LVA therapy demonstrates significant positive effects in the treatment of severe,deformed stage III lymphedema. 展开更多
关键词 Lower extremity lymphedema Endometrial cancer Lymphaticovenous anastomosis complex decongestive therapy Gynecological malignancies Recurrent infection Case report
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Discussion on the Complex Structure of Nilpotent Lie Groups Gk
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作者 Caiyu Du Yu Wang 《Open Journal of Applied Sciences》 2024年第6期1401-1411,共11页
Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent... Consider the real, simply-connected, connected, s-step nilpotent Lie group G endowed with a left-invariant, integrable almost complex structure J, which is nilpotent. Consider the simply-connected, connected nilpotent Lie group Gk, defined by the nilpotent Lie algebra g/ak, where g is the Lie algebra of G, and ak is an ideal of g. Then, J gives rise to an almost complex structure Jk on Gk. The main conclusion obtained is as follows: if the almost complex structure J of a nilpotent Lie group G is nilpotent, then J can give rise to a left-invariant integrable almost complex structure Jk on the nilpotent Lie group Gk, and Jk is also nilpotent. 展开更多
关键词 Almost complex Structure Nilpotent Lie Group Nilpotent Lie Algebra
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MicroRNA-451 from Human Umbilical Cord-Derived Mesenchymal Stem Cell Exosomes Inhibits Alveolar Macrophage Autophagy via Tuberous Sclerosis Complex 1/Mammalian Target of Rapamycin Pathway to Attenuate Burn-Induced Acute Lung Injury in Rats
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作者 Zhigang Jia Lin Li +5 位作者 Peng Zhao Guo Fei Shuangru Li Qinqin Song Guangpeng Liu Jisong Liu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第9期1030-1043,共14页
Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechan... Objective Our previous studies established that microRNA(miR)-451 from human umbilical cord mesenchymal stem cell-derived exosomes(hUC-MSC-Exos)alleviates acute lung injury(ALI).This study aims to elucidate the mechanisms by which miR-451 in hUC-MSC-Exos reduces ALI by modulating macrophage autophagy.Methods Exosomes were isolated from hUC-MSCs.Severe burn-induced ALI rat models were treated with hUC-MSC-Exos carrying the miR-451 inhibitor.Hematoxylin-eosin staining evaluated inflammatory injury.Enzyme-linked immunosorbnent assay measured lipopolysaccharide(LPS),tumor necrosis factor-α,and interleukin-1βlevels.qRT-PCR detected miR-451 and tuberous sclerosis complex 1(TSC1)expressions.The regulatory role of miR-451 on TSC1 was determined using a dual-luciferase reporter system.Western blotting determined TSC1 and proteins related to the mammalian target of rapamycin(mTOR)pathway and autophagy.Immunofluorescence analysis was conducted to examine exosomes phagocytosis in alveolar macrophages and autophagy level.Results hUC-MSC-Exos with miR-451 inhibitor reduced burn-induced ALI and promoted macrophage autophagy.MiR-451 could be transferred from hUC-MSCs to alveolar macrophages via exosomes and directly targeted TSC1.Inhibiting miR-451 in hUC-MSC-Exos elevated TSC1 expression and inactivated the mTOR pathway in alveolar macrophages.Silencing TSC1 activated mTOR signaling and inhibited autophagy,while TSC1 knockdown reversed the autophagy from the miR-451 inhibitor-induced.Conclusion miR-451 from hUC-MSC exosomes improves ALI by suppressing alveolar macrophage autophagy through modulation of the TSC1/mTOR pathway,providing a potential therapeutic strategy for ALI. 展开更多
关键词 Acute lung injury Human umbilical cord mesenchymal stem cell-derived exosomes MicroRNA-451 Tuberous sclerosis complex 1 Mammalian target of rapamycin pathway AUTOPHAGY
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Glutamatergic CYLD deletion leads to aberrant excitatory activity in the basolateral amygdala:association with enhanced cued fear expression
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作者 Huidong Li Faqin Li +8 位作者 Zhaoyi Chen Erwen Wu Xiaoxi Dai Danni Li Haojie An Shiyi Zeng Chunyan Wang Li Yang Cheng Long 《Neural Regeneration Research》 SCIE CAS 2025年第11期3259-3272,共14页
Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-... Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear memory.Cylindromatosis(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B pathway.CYLD is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly expressed.Emerging studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like behaviors.However,the precise role of CYLD in glutamatergic neurons is largely unknown.Here,we first proposed involvement of CYLD in cued fear expression.We next constructed transgenic model mice with specific deletion of Cyld from glutamatergic neurons.Our results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male mice.Further,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male mice.Altogether,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial activation.This may contribute,at least in part,to cued fear expression. 展开更多
关键词 basolateral amygdala cued fear expression cylindromatosis deubiquitinase glutamate receptor 1 glutamatergic neuron microglial activation N-methyl-D-aspartate receptor 1 neuronal activation synaptic transmission
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Cu-Fe合金凝固过程中结构变化研究
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作者 王旭锋 张真豪 +3 位作者 高绪锋 金雅璇 张寒雨 李运刚 《原子与分子物理学报》 CAS 北大核心 2025年第6期183-192,共10页
采用分子动力学模拟方法研究了Cu_(100-X)Fe_(X)(X=1%、3%、5%)合金在冷却速率为2×10^(10)K/s条件下合金凝固过程.研究表明,Fe含量为1%时,随着合金温度的降低Fe原子始终保持均匀分布的状态,未出现Fe原子聚集现象,晶体结构是以FCC... 采用分子动力学模拟方法研究了Cu_(100-X)Fe_(X)(X=1%、3%、5%)合金在冷却速率为2×10^(10)K/s条件下合金凝固过程.研究表明,Fe含量为1%时,随着合金温度的降低Fe原子始终保持均匀分布的状态,未出现Fe原子聚集现象,晶体结构是以FCC为主的Cu基体,Fe原子以固溶形式存在于基体中.Fe含量为3%时,随着合金温度的降低Fe原子有聚集趋势,但BCC晶体结构占比较小,晶体结构仍是以FCC为主的Cu基体.Fe含量为5%,随着合金温度的降低Fe原子发生明显聚集,最终形成以FCC、HCP晶体类型为主镶嵌Fe原子的Cu基体.研究了Fe团簇的形成过程,结果表明,Fe团簇的形成、长大是一个连续的过程,该过程受形核生长机制控制,不同阶段形成Fe团簇的大小和数量受Fe-Fe原子相互作用力、Fe原子的扩散能力以及Fe团簇与Cu基体间的界面能三个因素共同影响. 展开更多
关键词 cu-FE合金 快速凝固 晶体结构 Fe团簇
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Growth Response and Metal Accumulation of Sedum alfredii to Cd/Zn Complex-Polluted Ion Levels 被引量:22
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作者 叶海波 杨肖娥 +2 位作者 何冰 龙新宪 石伟勇 《Acta Botanica Sinica》 CSCD 2003年第9期1030-1036,共7页
Sedum alfredii Hance has been identified as a new Zn-hyperaccumulator native to China. In this study, responses and metal accumulation of S alfredii were examined under Zn/Cd complex polluted conditions. The results s... Sedum alfredii Hance has been identified as a new Zn-hyperaccumulator native to China. In this study, responses and metal accumulation of S alfredii were examined under Zn/Cd complex polluted conditions. The results showed that optimal growth of S alfredii in terms of the maximum dry matter yield was observed at Zn/Cd complex level of 500/100 mumol/L. Plant cadmium (Cd) or zinc (Zn) concentrations increased with increasing Cd or Zn supply. During the 20 d treatment, the highest Cd concentration in the leaves reached 12.1 g/kg at Zn/Cd level of 50/400 mumol/L and that of Zn in the stems was 23.2 g/kg at Zn/Cd level of 1000/50 mumol/L. The distribution of Cd in different plant parts decreased in the order: leaf > stem greater than or equal to root, whereas that of Zn was: stem > leaf greater than or equal to root. The accumulation of Cd and Zn in the shoots and roots of S. alfredii increased with the increasing of Zn/Cd supply levels, peaked at Zn/Cd levels of 250/400 and 500/100 mumol/L, respectively. The highest Cd and Zn uptake by the shoots was approximately 5 and 11 mg/plant, and was over 20 and 10 times higher than those in the roots, respectively. Zn supply at levels less than or equal to 500 mumol/L increased plant Cd concentrations, whereas high Zn supply decreased root Cd but did not affect leaf Cd concentrations in S alfredii Low Cd supply increased Zn concentration in the leaves, but Cd supply higher than 50 mumol/L considerably reduced root Zn concentrations, especially at low Zn level. These results indicate that S. alfredii can tolerate high Zn/Cd complex levels and has an extraordinary ability to hyperaccumulate not only Zn but also Cd. It could provide a new valuable plant material for understanding the mechanisms responsible for co-hyperaccumulation of Zn and Cd as well as for phytoremediation of the Cd/Zn complex polluted soils. 展开更多
关键词 complex pollution cadmium (Cd) zinc (Zn) HYPERACcuMULATION Sedum alfredii
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Optimization of copper extraction for bioleaching of complex Cu-polymetallic concentrate by moderate thermophiles 被引量:4
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作者 王玉光 苏丽君 +4 位作者 曾伟民 邱冠周 万利利 陈新华 周洪波 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1161-1170,共10页
Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated ... Effects of initial pH, temperature, liquid volume, rotation speed, galvanic interaction (pyrite ratio) and pulp density on bioleaching of complex Cu-polymetallic concentrate were investigated. The results indicated that the copper extraction at pH 1.5 was 1.5 and 1.4 times that at pH 1.0 and pH 2.0 respectively. The copper extraction obtained at 45 ℃ was 1236.8%higher than that at 50 ℃. With the increase of rotation speed or the decrease of liquid volume, copper extraction was improved obviously. Copper extraction was improved gradually with the increase of pyrite ratio. However, when the ratio was higher than 20.0%, no further increase in copper extraction was observed. And the statistically significant interactive effects on copper extraction were found between temperature and pH, and temperature and pyrite ratio. 展开更多
关键词 moderate thermophiles BIOLEACHING complex cu-polymetallic concentrate copper extraction optimization
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Catalytic epoxidation of olefin over supramolecular compounds of molybdenum oxide clusters and a copper complex 被引量:3
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作者 高洪成 颜岩 +5 位作者 徐晓弘 于杰辉 牛会玲 高文秀 张文祥 贾明君 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1811-1817,共7页
The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.... The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates. 展开更多
关键词 Supramolecular compound Molybdenum oxide cluster Copper complex Olefin Epoxidation
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Fe_(73.5)Cu_(1.0)Mo_(3.0)Si_(13.5)B_(9.0 被引量:5
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作者 纪松 杨国斌 王润 《金属学报》 SCIE EI CAS CSCD 北大核心 1996年第1期69-74,共6页
用X射线衍射及磁测量等方法研究了不同退火温度下Fe_(73.5)Cu_(1.0)Mo_(3.0)Si_(13.5)B_(9.0)纳米软磁合金的结构与磁性.发现合金的显微组织结构与退火温度有关,退火温度为500─520℃时... 用X射线衍射及磁测量等方法研究了不同退火温度下Fe_(73.5)Cu_(1.0)Mo_(3.0)Si_(13.5)B_(9.0)纳米软磁合金的结构与磁性.发现合金的显微组织结构与退火温度有关,退火温度为500─520℃时,合金具有最佳软磁性能,合金中如出现Fe-B化合物,软磁性能恶化. 展开更多
关键词 纳米合金 Fe73.5cu1.0Mo3.0Si13.5B9.0 软磁合金 饱和磁致伸缩系数 有效磁各向异性 软磁材料 磁性
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急冷Cu_(30)Al_(70)合金的结构及催化特性 被引量:1
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作者 孙笠 宋启洪 胡壮麒 《金属学报》 SCIE EI CAS CSCD 北大核心 1996年第1期63-68,共6页
本文研究了急冷Cu_(30)Al_(70)合金及其制成的急冷骨架铜催化剂,并与工业上广泛应用的Cu_(30)Al_(70)合金催化剂进行了对比.结果表明:急冷Cu_(30)Al_(70)合金组织较均匀,单质Al相较少,Cu... 本文研究了急冷Cu_(30)Al_(70)合金及其制成的急冷骨架铜催化剂,并与工业上广泛应用的Cu_(30)Al_(70)合金催化剂进行了对比.结果表明:急冷Cu_(30)Al_(70)合金组织较均匀,单质Al相较少,Cu,Al元素分布均匀.急冷骨架铜催化剂比表面积较小,孔径大,孔容积较大.急冷骨架铜催化剂在木糖加氢反应中的催化活性高于普通的骨架铜催化剂. 展开更多
关键词 急冷 铜铝合金 骨架铜催化剂 催化活性 cu30Al70合金
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尖音库蚊复合组(CulexpipiensComplex)生物分类学的研究:表皮碳氢化合物的气相色谱分析 被引量:5
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作者 赵彤言 周方 +1 位作者 陈立菌 陆宝麟 《寄生虫与医学昆虫学报》 CAS 1996年第1期36-43,共8页
本文报告了我国尖音库蚊复合组尖音库蚊、淡色库蚊和致倦库蚊表皮碳氢化合物的气相色谱分析,并与本复合组分布于日本的骚扰库蚊以及亲缘种迷走库蚊进行了比较。结果表明,尖音库蚊、淡色库蚊、致倦库蚊和骚扰库蚊表皮碳氢化合物的主要... 本文报告了我国尖音库蚊复合组尖音库蚊、淡色库蚊和致倦库蚊表皮碳氢化合物的气相色谱分析,并与本复合组分布于日本的骚扰库蚊以及亲缘种迷走库蚊进行了比较。结果表明,尖音库蚊、淡色库蚊、致倦库蚊和骚扰库蚊表皮碳氢化合物的主要组分相同,含量存在着某些差异,与迷走库蚊相比则有较大的差异,而在一定程度上表现出复合组的特征。 展开更多
关键词 尖音库蚊复合组 表皮 气相色谱 分类
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Cu/Ce负载对赤泥脱除中低温烟气中NO的促进作用
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作者 李扬 徐博 +2 位作者 杨赫 靳立军 胡浩权 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第3期362-372,共11页
本研究对酸洗赤泥催化剂进行Cu、Ce、Cu/Ce浸渍负载,并研究了金属改性赤泥对烟气中NOx的催化转化性能。研究结果表明,Cu负载催化剂中的Cu+与Cu^(2+),有效促进了赤泥对低温烟气(200–300℃)中的NO转化率,Cu的负载量达到6%时,赤泥的最高N... 本研究对酸洗赤泥催化剂进行Cu、Ce、Cu/Ce浸渍负载,并研究了金属改性赤泥对烟气中NOx的催化转化性能。研究结果表明,Cu负载催化剂中的Cu+与Cu^(2+),有效促进了赤泥对低温烟气(200–300℃)中的NO转化率,Cu的负载量达到6%时,赤泥的最高NO转化率达到了90.7%;而Ce负载催化剂中的Ce^(3+)与Ce^(4+),有效促进了赤泥对中温烟气(200–400℃)中的NO转化率,Ce的负载量达到8%时,赤泥的最高NO转化率达到了94.0%;Cu/Ce负载催化剂表现出比单金属负载催化剂更好的低温NO转化率,最佳的负载Cu:Ce比例为1∶1,双金属负载催化剂表现出比Cu负载催化剂更好的中温(300–400℃)中的NO转化率,最高达到了95.5%。其原因是,在Cu/Ce协同作用下,Cu+以及Cu^(2+)的还原过程分别从229、302℃降至201以及247℃,同时使发生Fe2O3→FeO的还原过程的温度降低,促使ACRM-Cu1Ce1具有更强的低温氧化还原能力,同时,双金属负载使催化剂具有更高的弱酸性峰,也使催化剂的强、弱酸性峰都向低温偏移,并使负载后的赤泥具有了较高的Fe离子平均氧化态以及较高的Cu+含量,促进了赤泥催化剂对低温NO的转化率。 展开更多
关键词 赤泥 SCR cu CE 负载
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Cu(Ⅱ),Ni(Ⅱ)Complexation with Acid Alizarine Blue B in the Presence of Cetyltrimethylammonium Bromide
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作者 沈荣 郜洪文 俞汉青 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期178-182,共5页
The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral co... The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed. 展开更多
关键词 Microsurface adsorption-spectral correction technique Langmuir aggregation Acid alizarine blue B Cetyltrimethylammonium bromide Ternary complex
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Study on Curative Effect of Perforated Injection of Zinc-ammonia Complex on Rosette Disease of Fruit Tree
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作者 王满平 《Plant Diseases and Pests》 CAS 2011年第2期70-72,共3页
[ Objective ] The paper was to explore a kind of zinc preparation suitable for injection on trees with fast, efficient and safe cure effect on physiological disease of zinc deficiency. [Method] Taking three years old ... [ Objective ] The paper was to explore a kind of zinc preparation suitable for injection on trees with fast, efficient and safe cure effect on physiological disease of zinc deficiency. [Method] Taking three years old apple, pear, peach and grape trees as the materials, the author studied the absorption condition of these trees to six kinds of zinc substances and their security. The sealed curative effects of the injected zinc substances which were harmful and could be absorbed steadily by the fruit trees against rosette disease were studied. [ Result] The results of absorption condition and security experiments showed that only zinc-mmnonia complex could be absorbed steadily and safely throughout four seasons. When apple, pear, peach and grape trees affected by rosette disease were injected with zinc- ammonia complex, the leaves of those trees started to grow obviously after 10 d; the internodes of diseased branches elongated, the leaves turned bigger, and the ap- pearance of branches became normal after about 25 d. [ Conclusion] The curative effect of perforated injection of zinc-ammonia complex on fruit tree rosette disease was remarkable. The results also provided a new way for the cure of deficiency diseases of other trace elements. 展开更多
关键词 Fruit tree Zinc-ammonia complex Perforated injection Rosette disease
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Cu、Sn、Ag同位素在古金属制品溯源研究中的应用
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作者 程文斌 郎兴海 +6 位作者 欧阳辉 彭义伟 陈翠华 谢富伟 王勇 彭强 杨超 《地质学报》 EI CAS CSCD 北大核心 2024年第7期2001-2024,共24页
近年来,随着同位素分析方法的不断突破和新一代多接收电感耦合等离子体质谱(MC-ICP-MS)测试技术的广泛应用,Cu、Sn、Ag等非传统同位素在古代金属制品溯源研究中显示出较好的应用前景。本文综述了近20年来Cu、Sn、Ag同位素在古代金属制... 近年来,随着同位素分析方法的不断突破和新一代多接收电感耦合等离子体质谱(MC-ICP-MS)测试技术的广泛应用,Cu、Sn、Ag等非传统同位素在古代金属制品溯源研究中显示出较好的应用前景。本文综述了近20年来Cu、Sn、Ag同位素在古代金属制品应用研究的相关进展,并展望了其应用前景:①由于不同矿床之间Cu、Sn、Ag同位素存较大重叠,这些同位素均难以作为独立的证据追溯金属制品的地质来源;②Cu同位素在原生矿石与表生矿石之间存在较大的分馏,是示踪铜矿石类型的可靠方法,Ag同位素也具推断银矿石类型的潜力;③将Cu、Sn、Ag同位素与Pb同位素、微量元素相结合,并采用合理的统计方法,开展综合溯源研究将是今后应用非传统同位素进行古代金属制品溯源研究的发展方向。 展开更多
关键词 cu同位素 Sn同位素 Ag同位素 古代金属制品 溯源研究
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