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系统工程理论方法应用 1995年第4期4卷 33-39页

作者：马永开杨桂元唐小我安徽财贸学院电子科技大学管理学院

本文引入了非负权重组合预测冗余方法的概念，提出了几个删除冗余方法的定理．这几个冗余定理能简化非负权重最优组合预测问题，并用几个实例表明了这些冗余定理的有效性．

关键词：非负权重组合预测冗余定理

基于矩阵的多维关联规则算法在烟叶复烤配方的应用研究

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计算机与数字工程 2019年第1期47卷 253-257页

作者：王萝萍唐兴宏钱颖颖马永凯于春霞秦玉华云南中烟工业有限责任公司技术中心昆明650024 青岛海大新星计算机工程中心青岛266071 青岛科技大学信息科学技术学院青岛266061

针对Apriori算法频繁扫描数据库造成的I/O开销大等问题以及烟叶复烤配方模块多维数据挖掘的需求,论文在经典Apriori算法的基础上,提出了一种基于矩阵的多维关联规则改进算法,该算法通过构造多维事务矩阵,减少了扫描数据库的次数,同时不... 详细信息

针对Apriori算法频繁扫描数据库造成的I/O开销大等问题以及烟叶复烤配方模块多维数据挖掘的需求,论文在经典Apriori算法的基础上,提出了一种基于矩阵的多维关联规则改进算法,该算法通过构造多维事务矩阵,减少了扫描数据库的次数,同时不断通过剪枝、剔除冗余事务对矩阵进行压缩,有效提高了挖掘效率。利用该算法对历史复烤配方数据进行了挖掘分析,结果表明该方法能够有效地将配方数据中隐含的诸多配方专家的配方维护行为规律提取为规则表示形式,从而挖掘出配方模块中烟叶的搭配和协同信息。该方法减少了配方研发人员的工作量,可有效地指导实际配方设计和维护工作。

关键词：复烤模块配方多维关联规则矩阵 Apriori算法

Characterization ofanovel deep-seamicrobial esterase EstC 10 and its use in the generation o f(R)-methyl 2-chloropropionate

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Journal of Oceanology and Limnology 2018年第2期36卷 473-482页

作者： GONG Yanhui ma Sanmei WANG Yongfei XU yongkai SUN Aijun ZHANG Yun HU Yunfeng Key Laboratory of Tropical marine Bio-Resources and Ecology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Guangdong Key Laboratory of marine materia Mediea South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Department ofBiotechnology Jinan University Guangzhou 510632 China Affiliated Hospital of Shandong University of Traditional Chinese Medicine Jinan 250014 China South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center Guangzhou 510275 China

A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate （R）-methyl 2-chloropropionate with high enantiomeric excess （〉99%） after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration （80 mmol/L） of esterase EstC10 was higher than the kinetic resolution of another esterase, Estl2-7 （50 mmoFL）. The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of （R）-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.

关键词： biocatalysis deep-sea microorganisms novel esterase kinetic resolution (R)-methyl 2-chloropropionate

Family-level leaf nitrogen and phosphorus stoichiometry of global terrestrial plants

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Science China(Life Sciences) 2019年第8期62卷 1047-1057页

作者： Di Tian Zhengbing Yan Suhui ma Yuehong Ding yongkai Luo Yahan Chen Enzai Du Wenxuan Han Emoke Dalma Kovacs Haihua Shen Huifeng Hu Jens Kattge Bernhard Schmid Jingyun Fang College of Life Sciences Capital Normal UniversityBeijing100048China Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry ofEducationPeking UniversityBeijing100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China College of Resources Science&Technology and State Key Laboratory of Earth Surface Processes and Resource EcologyBeijing NormalUniversityBeijing100875China Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina AgriculturalUniversityBeijing100193China National Institute for Research and Development in Optoelectronics INCDO-INOE2000 Research Institute for Analytical InstrumentationICIA subsidiaryCluj-Napoca400293Romania max-Planck-Institute for Biogeochemistry Jena07745Germany Department of Evolutionary Biology and Environmental Studies University of ZurichZurich8057Switzerland

Leaf nitrogen(N) and phosphorus(P) concentrations are critical for photosynthesis, growth, reproduction and other ecological processes of plants. Previous studies on large-scale biogeographic patterns of leaf N and P stoichiometric relationships were mostly conducted using data pooled across taxa, while family/genus-level analyses are rarely reported. Here, we examined global patterns of family-specific leaf N and P stoichiometry using a global data set of 12,716 paired leaf N and P records which includes 204 families, 1,305 genera, and 3,420 species. After determining the minimum size of samples(i.e., 35 records), we analyzed leaf N and P concentrations, N:P ratios and N^P scaling relationships of plants for 62 families with 11,440 records. The numeric values of leaf N and P stoichiometry varied significantly across families and showed diverse trends along gradients of mean annual temperature(maT) and mean annual precipitation(maP). The leaf N and P concentrations and N:P ratios of 62 families ranged from 6.11 to 30.30 mg g–1, 0.27 to 2.17 mg g–1, and 10.20 to 35.40, respectively. Approximately 1/3–1/2 of the families(22–35 of 62) showed a decrease in leaf N and P concentrations and N:P ratios with increasing maT or maP, while the remainder either did not show a significant trend or presented the opposite pattern. Family-specific leaf N^P scaling exponents did not converge to a certain empirical value, with a range of 0.307–0.991 for 54 out of 62 families which indicated a significant N^P scaling relationship. Our results for the first time revealed large variation in the family-level leaf N and P stoichiometry of global terrestrial plants and that the stoichiometric relationships for at least one-third of the families were not consistent with the global trends reported previously. The numeric values of the family-specific leaf N and P stoichiometry documented in the current study provide critical synthetic parameters for biogeographic modeling and for further stud

关键词： leaf nitrogen (N) leaf phosphorus (P) plant stoichiometry family N:P ratios N^P scaling relationship climate

Weakened interlayer coupling in two-dimensional MoSe2 flakes with screw dislocations

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Nano Research 2019年第8期12卷 1900-1905页

作者： Xiangzhuo Wang Huixia Yang Rong Yang Qinsheng Wang Jingchuan Zheng Lu Qiao Xianglin Peng yongkai Li Dongyun Chen Xiaolu Xiong Junxi Duan Guangyu Zhang Jie ma Junfeng Han Wende Xiao Yugui Yao Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement (MOE) Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systemsand School of PhysicsBeijing Institute of TechnologyBeijing 100081China Micronano Center Beijing Institute of TechnologyBeijing 100081China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The screw dislocations are intriguing defects that are often observed in natural and artificial materials. The dislocation spirals break the reflection and inversion symmetries of the lattices and modify the interlayer coupling in layer-structured materials, inducing additional complexity in layer stacking and thus novel properties in materials. Here, we report on the interlayer coupling of two-dimensional (2D) MoSe2 flakes with screw dislocations by atomic force microscopy (AFM), Raman spectra and photoluminescence (PL) spectra. By controlling the supersaturation conditions, 2D MoSe2 flakes with screw dislocations are grown on amorphous SiO2 substrates by chemical vapor deposition (CVD). AFM measurements reveal that the interlayer spacing in such 2D MoSe2 flakes with screw dislocation is slightly widened with respect to the normal AA- or AB-stacked ones due to the presence of the screw dislocations. Raman and PL spectra show that the interlayer coupling is weaker and thus the band gap is wider than that in the normal AA- or AB-stacked ones. Our work demonstrates that the interlayer coupling of 2D transition metal dichalcogenides (TMDCs) flakes can be tuned by the induction of screw dislocations, which is very helpful for developing novel catalysts and electronic devices.

关键词： transition-metal dichalcogenides molybdenum selenide screw dislocations interlayer coupling band gap

Surface reconstruction,doping and vacancy engineering to improve the overall water splitting of CoP nanoarrays

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Nano Research 2023年第1期16卷 228-238页

作者： yongkai Sun Wenyuan Sun Lihong Chen Alan Meng Guicun Li Lei Wang Jianfeng Huang Aili Song Zhenhui Zhang Zhenjiang Li College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061China College of materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOE College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China School of material Science and Engineering International S&T Cooperation Foundation of Shaanxi ProvinceXi’an Key Laboratory of Green Manufacture of Ceramic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Qingdao Huanghai University Qingdao 266000China

Development of a general regulatory strategy for efficient overall water splitting remains a challenging ***,a simple,costfairness,and general fluorination strategy is developed to realize surface reconstruction,heteroatom doping,and vacancies engineering over cobalt phosphide(CoP)for acquiring high-performance bifunctional ***,the surface of CoP nanoarrays(NAs)becomes rougher,meanwhile F doped into CoP lattice and creating amounts of P vacancies by fluorination,which caused the increase of active sites and regulation of charge distribution,resulting the excellent electrocatalyst performance of F-CoP NAs/copper foam(CF).The optimized F-CoP NAs/CF delivers a lower overpotential of only 35 mV at 10 ma·cm^(−2)for hydrogen evolution reaction(HER)and 231 mV at 50 ma·cm^(−2)for oxygen evolution reaction(OER),and the corresponding overall water splitting requires only 1.48 V cell voltage at 10 ma·cm^(−2),which are superior to the most state-of-theart reported *** work provides an innovative and feasible strategy to construct efficient electrocatalysts.

关键词： fluorination surface reconstruction F atom doping P vacancies overall water splitting

Strong-field photoionization of intense laser fields by controlling optical singularities

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Science China(Physics,Mechanics & Astronomy) 2021年第7期64卷 91-97页

作者： Yiqi Fang Zhenning Guo Peipei Ge Xueyan ma Meng Han Xiaoyang Yu yongkai Deng Qihuang Gong Yunquan Liu State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing100871China Collaborative Innovation Center of Quantum matter Peking UniversityBeijing100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan030006China Peking University Yangtze Delta Institute of Optoelectronics Nantong226001China

The spatial features of a light field, such as in the form of the optical singularities, provide a new degree of freedom for the application of light fields in different areas of science and technology. However, although the exploration of structured light is growing rapidly, the investigation of strong-field photoionization using such light fields is noticeably lagging behind. Here, we present an experimental study that reveals the signatures of intense, structured light fields with controlled optical singularities in strong-field photoionization. The different types of optical singularities can be identified through photoionization observables,i.e., photoelectron momentum distributions(PMDs). By concurrently shifting the locations of the phase and polarization singularities, the focal electric field features can be designated, and subsequently, the photoionization appearances can be manipulated. In this process, the behaviors of the different intense optical singularities are clearly visualized by the PMDs. This work will advance both the strong-field science and singularity optics.

关键词： strong-field ionization optical singularity spin-orbit interaction

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异步轧制硅钢表面纳米结构稳定性与渗硅行为

金属学报 2016年第3期52卷 307-312页

作者：刘刚李超马野张瑞君刘勇凯沙玉辉东北大学研究院沈阳110819 东北大学材料电磁过程研究教育部重点实验室沈阳110819

对3%无取向硅钢进行异步轧制以实现表面纳米化,分别在真空和渗硅条件下进行不同参数的热处理,研究显微组织、物相和成分的演变.结果表明：经过速比为1.31,轧制道次为20,总压下量为91%的异步轧制后,板材表面形成了尺寸为10-20 nm,取向呈... 详细信息

对3%无取向硅钢进行异步轧制以实现表面纳米化,分别在真空和渗硅条件下进行不同参数的热处理,研究显微组织、物相和成分的演变.结果表明：经过速比为1.31,轧制道次为20,总压下量为91%的异步轧制后,板材表面形成了尺寸为10-20 nm,取向呈随机分布的纳米晶;在真空下升温,表面纳米晶的再结晶温度明显提高;在渗硅剂（Si粉＋1%（质量分数）卤化物）中升温,表面纳米晶的再结晶温度因外部Si原子沿着缺陷的快速扩散而进一步提高,使得纳米晶界面能够在更高的温度下（750℃）发挥扩散通道作用,促进Si原子的扩散,并在显著地降低保温时间和（作为催化剂的）卤化物含量的同时获得致密的渗Si层.

关键词：硅钢异步轧制表面纳米化热稳定性渗硅

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涤纶长丝/微孔涤纶纤维同浴同色染色技术

纺织学报 2014年第6期35卷 68-73页

作者：马源周永凯张华北京服装学院北京100029 总后勤部军需装备研究所北京100082

由于涤纶长丝、微孔涤纶2种纤维的纤维表面及性能有很大的差别,因此即使同浴染色也会出现色光不一致的现象。本文通过耐碱性实验,确定了涤纶长丝及微孔涤纶的碱减量氧漂前处理工艺为:浴比1∶30,烧碱质量浓度6 g/L,高温去油剂质量浓度0.4... 详细信息

由于涤纶长丝、微孔涤纶2种纤维的纤维表面及性能有很大的差别,因此即使同浴染色也会出现色光不一致的现象。本文通过耐碱性实验,确定了涤纶长丝及微孔涤纶的碱减量氧漂前处理工艺为:浴比1∶30,烧碱质量浓度6 g/L,高温去油剂质量浓度0.4 g/L,130℃下处理20 min。为了减小2组分纤维的色差,通过分散染料筛选,确定了使2种份纤维表面得色深度K/S值相对较大,且色差△E相对较小、同色性较好的三原色分散染料:JRB蓝、JFG黄、JFRB红,并且分别探讨了染料用量、染色时间、染色温度、染色pH值4个因素对涤纶长丝及微孔涤纶纤维染色同色性的影响。

关键词：涤纶长丝微孔涤纶同浴染色同色性

Research on Low-temperature Energy Consumption Test Procedures of BEV based on Road Travel Data

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Research on Low-temperature Energy Consumption Test Procedur...