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DFT study of the conductance of molecular wire:The effect of coupling geometry and intermolecular interaction on the transport properties

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Science China Chemistry 2006年第6期49卷 492-498页

作者： QI Yuanhua1,2. GUAN Daren1 & LIU Chengbu1 1. Institute of Theoretical Chemistry, Shandong University, Jinan 2.0100, China 2. School of Physics and Microelectronics, Shandong University, Jinan 2.0061, China 1. Institute of Theoretical Chemistry Shandong University Jinan 250100 China 2. School of Physics and Microelectronics Shandong University Jinan 250061 China

The density functional theory (DFT) combining with the non-equilibrium Green functions (NEGF) method is applied to the study of the electronic transport properties for a Di-thiol-benzene (DTB) molecule coupled to two Au(111) surfaces. The dependence of the transport properties on the bias, the coupling geometry of the molecule-electrode interface, and the intermolecular interaction are examined in detail. The results show that the existence of the hydrogen atom at the end of the DTB molecule would significantly decrease the transmission coefficients, and then the differential conductance (dI/dV). By changing the position of the DTB molecule located between two electrodes a maximum value of calculated current is observed. It is also found that the intermolecular interaction will strongly influence the transport properties of the system studied.

关键词： non-equilibrium Green functions method, transmission spectrum, the molecular projected selfconsistent Hamiltonian, projected density of state.

碳五回炼对甲醇制烯烃(MTO)反应性能的影响研究

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现代化工 2024年第2期44卷 240-245页

作者：王志军国能包头煤化工有限责任公司内蒙古包头014000

甲醇制烯烃(MTO)装置副产混合碳五。为提高碳五组分的高值化利用,国能包头MTO装置采用再生催化剂输送管碳五回炼工艺。混合碳五预裂解增产乙烯和丙烯,同时实现对催化剂的预积碳,提高MTO催化剂活性。通过对比碳五回炼前后装置产出组分的... 详细信息

甲醇制烯烃(MTO)装置副产混合碳五。为提高碳五组分的高值化利用,国能包头MTO装置采用再生催化剂输送管碳五回炼工艺。混合碳五预裂解增产乙烯和丙烯,同时实现对催化剂的预积碳,提高MTO催化剂活性。通过对比碳五回炼前后装置产出组分的差异,分析碳五回炼对MTO反应性能的影响,结果表明,乙烯和丙烯总收率提高1.03%,乙丙比(乙烯和丙烯比值)降低0.011,综合经济效益提高2.512./h。

关键词：甲醇制烯烃 MTO催化剂碳五裂解乙烯丙烯

CHCHD2.Thr61Ile mutation impairs F1F0-ATPase assembly in in vitro and in vivo models of Parkinson's disease

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Neural Regeneration Research 2024年第1期19卷 196-204页

作者： Xiang Chen Yuwan Lin zhiling Zhang Yuting Tang Panghai Ye Wei Dai Wenlong Zhang Hanqun Liu Guoyou peng Shuxuan Huang Jiewen Qiu Wenyuan Guo Xiaoqin Zhu Zhuohua Wu Yaoyun Kuang Pingyi Xu Miaomiao Zhou Department of Neurology The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Neurology The People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina School of Basic Medical Sciences Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Neurology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Mitochondrial dysfunction is a significant pathological alte ration that occurs in Parkinson's disease(PD),and the Thr61lle(T61I)mutation in coiled-coil helix coiled-coil helix domain containing 2.CHCHD2.,a crucial mitochondrial protein,has been reported to cause Parkinson's ***-ATPase participates in the synthesis of cellular adenosine triphosphate(ATP)and plays a central role in mitochondrial energy ***,the specific roles of wild-type(WT)CHCHD2.and T611-mutant CHCHD2.in regulating F1FO-ATPase activity in Parkinson's disease,as well as whether CHCHD2.or CHCHD2.T61I affects mitochondrial function through regulating F1FO-ATPase activity,remain unclea ***,in this study,we expressed WT CHCHD2.and T61l-mutant CHCHD2.in an MPP^(+)-induced SH-SY5Y cell model of *** found that CHCHD2.protected mitochondria from developing MPP^(+)-induced *** normal conditions,ove rexpression of WT CHCHD2.promoted F1FO-ATPase assembly,while T61I-mutant CHCHD2.appeared to have lost the ability to regulate F1FO-ATPase *** addition,mass spectrometry and immunoprecipitation showed that there was an interaction between CHCHD2.and *** weeks after transfection with AAV-CHCHD2.T61I,we intraperitoneally injected 1-methyl-4-phenyl-1,2.3,6-tetrahydropyridine into mice to establish an animal model of chronic Parkinson's disease and found that exogenous expression of the mutant protein worsened the behavioral deficits and dopaminergic neurodegeneration seen in this *** findings suggest that WT CHCHD2.can alleviate mitochondrial dysfunction in PD by maintaining F1F0-ATPase structure and function.

关键词： ATP synthase(F1F0-ATPase) coiled-coil helix coiled-coil helix domain containing 2 dopaminergic neuron mitochondrial dysfunction neurodegeneration oligomycin sensitivity-conferring protein Parkinson's disease T61I mutation tyrosine hydroxylase

不同灌溉水盐度下土壤真菌群落对生物炭施用的响应

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环境科学 2024年第1期45卷 520-529页

作者：郑志玉郭晓雯闵伟石河子大学农学院石河子832003

咸水灌溉可缓解干旱区淡水资源短缺的问题,但是长期咸水灌溉会破坏土壤真菌群落结构.为缓解盐分带来的危害,采用生物炭作为土壤改良剂,以改善土壤真菌群落结构.为探究施用生物炭对盐渍化土壤真菌群落结构多样性的影响,设置两个灌溉水盐... 详细信息

咸水灌溉可缓解干旱区淡水资源短缺的问题,但是长期咸水灌溉会破坏土壤真菌群落结构.为缓解盐分带来的危害,采用生物炭作为土壤改良剂,以改善土壤真菌群落结构.为探究施用生物炭对盐渍化土壤真菌群落结构多样性的影响,设置两个灌溉水盐度:0.35 dS·m^(-1)(淡水)和8.04 dS·m^(-1)(咸水),在每个灌溉水盐度下,设置2.生物炭施用水平:0 t·hm^(-2.(不施)和3.7 t·hm^(-2.(施用).高通量测序结果表明,与淡水灌溉相比,咸水灌溉增加了真菌群落物种多样性,降低了真菌群落物种丰富度;在咸水灌溉条件下施加生物炭降低了土壤真菌群落物种多样性和物种丰富度.各处理土壤的优势菌门为:子囊菌门、被孢菌门、担子菌门、壶菌门、球囊菌门和罗兹菌门,优势菌属为:赤霉菌属、Sarocladium、毛壳菌属、镰刀菌属和葡萄穗霉属.与淡水灌溉相比,咸水灌溉显著增加担子菌门和壶菌门的相对丰度,显著降低子囊菌门和罗兹菌门的相对丰度.咸水灌溉的条件下施用生物炭显著增加子囊菌门和Sarocladium的相对丰度,显著降低担子菌门、毛壳菌属和镰刀菌属的相对丰度.LEfSe差异分析表明,在不施生物炭的条件下,咸水灌溉降低真菌群落潜在生物标志物数量,而咸水灌溉的条件下施用生物炭增加真菌群落潜在生物标志物数量.以上结果表明,施用生物炭能够改善盐渍化土壤环境和真菌群落结构,为干旱区合理咸水灌溉和培肥土壤提供理论依据.

关键词：灌溉水盐度生物炭真菌 LEfSe分析高通量测序

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无机盐化合物对旧报纸脱墨效果的影响

中国造纸 2004年第12期23卷 11-13页

作者：张世杰韩卿 2.刘焕彬陕西科技大学造纸工程学院陕西咸阳712081 华南理工大学制浆造纸工程国家重点实验室广州510640

察了在旧报纸 (ONP)脱墨过程中添加无机盐化合物后脱墨分散体系的Zeta电位、浊度、吸光率、透射率几种参数的变化 ,进一步探讨了Zeta电位等参数的变化与脱墨浆残余油墨量及白度的关系。结果表明 ,添加适量的无机盐化合物对脱墨分散体系... 详细信息

察了在旧报纸 (ONP)脱墨过程中添加无机盐化合物后脱墨分散体系的Zeta电位、浊度、吸光率、透射率几种参数的变化 ,进一步探讨了Zeta电位等参数的变化与脱墨浆残余油墨量及白度的关系。结果表明 ,添加适量的无机盐化合物对脱墨分散体系中油墨粒子的脱除有积极的促进作用 ,脱墨体系的Zeta电位、浊度等参数与脱墨浆的质量性能之间存在较好的函数关系。 3种无机盐化合物对脱墨浆残余油墨量和白度的影响程度依次为CaCl2.>Al2.(SO4 ) 3>MgCl2.。

关键词：无机盐化合物脱墨浊度残余油墨量白度

A new sequential learning algorithm for RBF neural networks

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Science China(Technological Sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU zhiyuan2.1. Department of Power Engineering, Southeast University, Nanjing 2.0096, China 2. Department of Power Engineering, Nanjing Institute of Technology, Nanjing 2.0013, China 1. Department of Power Engineering Southeast University 210096 Nanjing China 2. Department of Power Engineering Nanjing Institute of Technology 210013 Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

YOLO-POD:基于多维注意力机制的高精度PCB微小缺陷检测算法

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电子学报 2024年第7期52卷 2515-2528页

作者：郭艳王智文赵润星广西科技大学自动化学院广西柳州545616 广西科技大学电子工程学院广西柳州545006

随着电子设备的广泛应用,印刷电路板(Printed Circuit Board,PCB)在电子制造行业中具有重要意义.然而,由于制造过程中的不完美和环境因素的干扰,PCB上可能存在微小的缺陷.因此,开发高效准确的缺陷检测算法对于确保产品质量至关重要.针对... 详细信息

随着电子设备的广泛应用,印刷电路板(Printed Circuit Board,PCB)在电子制造行业中具有重要意义.然而,由于制造过程中的不完美和环境因素的干扰,PCB上可能存在微小的缺陷.因此,开发高效准确的缺陷检测算法对于确保产品质量至关重要.针对PCB微小缺陷检测问题,本文提出了一种基于多维注意力机制的高精度PCB微小缺陷检测算法.为降低网络的模型参数量和计算量,引入部分卷积(Partial Convolution,PConv),将ELAN(Efficient Layer Aggregation Network)模块设计为更加高效的P-ELAN,同时,为增强网络对微小缺陷的特征提取能力,引入多维注意力机制(Multi-Dimensional Attention Mechanism,MDAM)的全维动态卷积(Omni-dimensional Dynamic Convolution,ODConv)并结合部分卷积,设计了POD-CSP(Partial ODconv-Cross Stage Partial)和POD-MP(Partial ODconv-Max Pooling)跨阶段部分网络模块,提出了OD-Neck结构.最后,本文基于(Youo Only Look Once version 7,YOLOv7)提出了对小目标更加高效的YOLO-POD模型,并在训练阶段采用一种新颖的Alpha-SIoU损失函数对网络进行优化.实验结果表明,YOLO-POD的检测精确率和召回率分别达到了98.31%和97.09%,并在多个指标上取得了领先优势,尤其是对于更严格的(mean Average Precision at IoU threshold of 0.75,mAP75)指标,比原始的YOLOv7模型提高2.%.验证了YOLO-POD在PCB缺陷检测性能中具有较高的准确性和鲁棒性,满足高精度的检测要求,可为PCB制造行业提供有效的检测解决方案.

关键词：印刷电路板小目标缺陷检测 POD-CSP POD-MP 全维动态卷积多维注意力机制

“双碳”战略下构建面向未来气候适应型城镇排水系统

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中国给水排水 2024年第8期40卷 1-10页

作者：刘智晓刘龙志吴凡松中国市政工程华北设计研究总院有限公司天津300381 清华大学环境学院北京100084 长江生态环保集团有限公司湖北武汉430014

城市水安全是城市安全的基石和生命健康维系的基础,排水系统是链接人类生命健康与水环境、清洁供水和生活排泄物最终去向的纽带。在梳理排水系统发展历史基础上,分析了古代(基于水利用)、近代(卫生驱动型)、现代(水质与水量驱动型)三个... 详细信息

城市水安全是城市安全的基石和生命健康维系的基础,排水系统是链接人类生命健康与水环境、清洁供水和生活排泄物最终去向的纽带。在梳理排水系统发展历史基础上,分析了古代(基于水利用)、近代(卫生驱动型)、现代(水质与水量驱动型)三个不同历史时期排水系统的特点,总结了污水生物处理阶段性总体技术特征;针对全球气候变暖导致的极端降雨日趋增多、“双碳”战略等外部环境的约束,分析了传统城镇排水系统面临的挑战,在此基础上提出了构建面向未来气候适应型可持续城市排水系统,以实现现代排水系统从水质与水量型向气候适应型的转变。同时分析了流域视角下气候适应型排水系统的“Safe&SuRe”准则,介绍了以气候变化模型模拟及预测为基础的“降尺度”总体技术路线及理念,以及实现流域不同尺度上的技术及管控协同、资源源头转向能源化和资源化、智慧流域视角下实时控制系统等应对策略及路径。

关键词：极端降雨事件城镇排水系统韧性低碳智慧流域实时控制

Electric-stimulus rate encoding algorithm of Mandarin tonal information in cochlear implant

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Progress in Natural Science:Materials International 2006年第12期16卷 1315-1321页

作者： GUAN Tian~1, GONG Qin~1 and YE Datian~2.*(1. Department of Biomedical Engineering, Tsinghua University, Beijing 100084, China 2. Research Center of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China) [a]Department of Biomedical Engineering Tsinghua University Beijing China [b]Research Center of Biomedical Engineering Graduate School at Shenzhen Tsinghua University Shenzhen China

The modern multi-channel cochlear implants usually extract and encode the temporal envelope cues. This kind of algorithms can hardly satisfy the users who speak tonal languages, such as Mandarin. Many studies have tried to enhance the recognition ability of Mandarin through encoding tonal information and made suggestions to frequency-modulate the fixed pulse-rate carrier with the extracted tonal information based on the rate-pitch theory in electric hearing. However, how to encode and deliver the tonal information such as F_0by changing electric-stimulus rate has not got further study in clinical electric-stimulus mode. The present paper focuses on this matter by piecewise calculating the appreciable electric-stimulus rates. Then an electric-stimulus encoding algorithm of Mandarin tone is brought forward and testified through acoustic simulations. Such conclusion can be drawn that this algorithm of electric-stimulus rate could convey tonal information well and help to enhance the Mandarin speech recognition ability.

关键词： cochlear implant tone fundamental frequency electric-stimulus rate.