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The impact of land use change on quality evolution of soil genetic layers on the coastal plain of south Hangzhou Bay

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Journal of Geographical Sciences 2008年第4期18卷 469-482页

作者： LI Jialin LI Weifang YANG xiaoping ZHANG Dianfa tong Yiqing Coastal Resources and Environment Research Center Ningbo University Ningbo 315211 China

Land use change plays an important part in the studies of global environmental change and regional sustainable development. The change of soil quality can particularly reflect the impacts of human socio-economic activities on environment. Taking the coastal plain of south Hangzhou Bay as a study case, we analyzed the effects of land use changes on organic matter （OM）, total nitrogen （TN）, total phosphorus （TP）, available phosphorus （AP）, available potassium （AK）, total salinity （TS）, pH value in soil genetic layers, and assessed soil quality change related to different land use types from 1982 to 2003. The results show that：（1） The general change tendency of soil quality in the coastal plain of south Hangzhou Bay declined obviously in A layer and slightly rise in B （or P） layer and C （or W） layer. The contents of TP decreased generally in all soil genetic layers, but the variety difference of other soil quality indices was relatively great. （2） The change of soil quality in the areas where land use changed is far more remarkable than that with land use unchanged. The value of quality variety is A layer 〉B （or P） layer 〉C （or W） layer. （3） The changes of soil tillage, cultivation, fertilization, irrigation and drainage activities related to land use may make some soil-forming processes disappeared and bring in other new processes which will affect the soil quality and soil genetic layers directly.

关键词： land use soil quality soil genetic layer coastal plain south Hangzhou Bay

A versatile cloning vector facilitates target geneexpression in prokaryotic and eukaryotic cells

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Journal of Medical Colleges of PLA(China) 2011年第4期26卷 204-212页

作者： Wang Sheng Chen Jinhui Zhang Baozhong Liu Dabin Zhang Xin Mi Zhiqiang An xiaoping tong Yigang State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology Beijing 100071 China

Objective： To facilitate manipulation of gene expression in different host cells, we used pEGFP-N1 as backbone to construct a versatile vector that can drive foreign gene expression in prokaryotic and eukaryotic cells. Methods： A cloning and expression vector, pEGFP-NI-lac, was constructed by inserting the prokaryotic lac promoter of pUC 19 into the eukaryotic expression vector, pEGFP-N1, between the eukaryotic PCMV promoter and enhanced green fluorescent protein （EGFP） open reading frames. To assess the function of pEGFP-NI-lac, the nucleotide sequence encoding the hepatitis C virus （HCV） core protein was cloned into the multiple cloning sites. Western blotting analysis was used to detect the expression of the HCV core protein in Escherichia coli DH5a and HepG2 cells. Results： Restriction enzyme digestion and sequence analysis indicated that pEGFP-NI-lac was successfully constructed and the HCV core gene was cloned into this vector. The Western blotting results showed that pEGFP-NI-lac promoted expression of HCV core gene in prokaryotic E. coli DH5a and eukaryotic HepG2 cells. Conclusion： The pEGFP-NI-lac vector has been successfully constructed and functions in both prokaryotic and eukaryotic cells. The EGFP reporter can be used as an insert-inactivation marker for clone selection or as an expression tag. This vector can be used for cloning and expression of genes in both prokaryotic and eukaryotic cells, making gene cloning, expression and functional studies convenient as well as time- and labor-efficient

关键词： Cloning Gene expression: Versatile vector

(DarkAI)Mapping the large-scale density field of dark matter using artificial intelligence

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 143-159页

作者： Zitong Wang Feng Shi Xiaohu Yang Qingyang Li Yanming Liu xiaoping Li School of Aerospace Science and Technology Xidian UniversityXi’an 710126China Department of Astronomy School of Physics and Astronomyand Shanghai Key Laboratory for Particle Physics and CosmologyShanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute and Key Laboratory for Particle Physics Astrophysics and CosmologyMinistry of EducationShanghai Jiao Tong UniversityShanghai 200240China Institute for Astronomy University of EdinburghRoyal ObservatoryEdinburgh EH93HJUnited Kingdom

Herein,we present a deep-learning technique for reconstructing the dark-matter density field from the redshift-space distribution of dark-matter *** built a UNet-architecture neural network and trained it using the COmoving Lagrangian Acceleration fast simulation,which is an approximation of the N-body simulation with 5123 particles in a box size of 500 h^(-1)***,we tested the resulting UNet model not only with training-like test samples but also with standard N-body simulations,such as the Jiutian simulation with 61443particles in a box size of 1000 h^(-1)Mpc and the ELUCID simulation,which has a different *** real-space dark-matter density fields in the three simulations can be reconstructed reliably with only a small reduction of the cross-correlation power spectrum at 1%and 10%levels at k=0.1 and 0.3 h Mpc-1,*** reconstruction clearly helps to correct for redshift-space distortions and is unaffected by the different cosmologies between the training(Planck2018)and test samples(WMAP5).Furthermore,we tested the application of the UNet-reconstructed density field to obtain the velocity&tidal field and found that this approach provides better results compared with the traditional approach based on the linear bias model,showing a 12.2%improvement in the correlation slope and a 21.1%reduction in the scatter between the predicted and true ***,our method is highly efficient and has excellent extrapolation reliability beyond the training *** provides an ideal solution for determining the three-dimensional underlying density field from the plentiful galaxy survey data.

关键词： dark matter large-scale structure cosmology

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教育机器人的应用现状

中国教育技术装备 2008年第16期 138-140页

作者：童小平北京师范大学教育技术学院

介绍教育机器人在机器人竞赛及课内外教学中的应用现状，并提出其教育价值。

关键词：教育机器人应用现状竞赛

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重庆向长江上游经济中心转型

港口经济 2007年第4期 10-11页

作者：童小平重庆市委

重庆1997年直辖之初,还是一个国企改革脱困面临重重阻力的老工业基地。

关键词：长江上游销售值重庆老工业基地经济

高光纯D-乳酸生产菌株假肠膜明串珠菌HL64-1的分离鉴定及其发酵特性

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食品工业科技 2024年第11期45卷 133-141页

作者：黄筱萍王通李鹏刘兰江西省科学院微生物研究所江西南昌330096

从自然界中筛选分离产酸菌是获得高光学纯度乳酸生产菌株有效的途径之一。从腐烂果实中分离获得一株产高光学纯度D-乳酸菌株HL64-1,经形态学、16S rDNA序列分析、序列相似性Blast比对分析鉴定为假肠膜明串珠菌(Leuconostoc pseudomesent... 详细信息

从自然界中筛选分离产酸菌是获得高光学纯度乳酸生产菌株有效的途径之一。从腐烂果实中分离获得一株产高光学纯度D-乳酸菌株HL64-1,经形态学、16S rDNA序列分析、序列相似性Blast比对分析鉴定为假肠膜明串珠菌(Leuconostoc pseudomesenteroides)。在基础发酵培养基中摇瓶发酵24 h,产D-乳酸的量达到62.18 g/L,产酸速率达2.59 g/(L·h),光学纯度达99.90%(ee);在5 L发酵罐中放大培养,通过补加碳源,发酵72 h,D-乳酸产量达到78.74 g/L,平均产酸速率达1.09 g/(L·h)。该菌株可以有效利用农业副产物花生饼粉和棉籽粉作为替代氮源以降低发酵原料成本。该菌还可利用木糖产生D-乳酸,且葡萄糖能显著提高木糖的利用效率,极具工业应用前景。

关键词： D-乳酸生产菌分离高光学纯度发酵木糖

基于岗位技能认证的企业数字化学习案例研究——以中国电信“大规模在线岗位技能认证”项目为例

同方期刊数据库博看期刊评论

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中国远程教育 2011年第5期 16-20,25页

作者：吴峰童小平黄志刚夏冰北京大学企业与教育研究中心北京大学教育学院中国电信学院在线学习教研中心

企业数字化学习与员工发展相结合,将会极大提高员工的学习积极性。发展企业数字化学习需要与企业人力资源政策相结合。本文以案例研究法,在深入实践调研的基础上,分析了中国电信的"大规模在线岗位技能认证"项目的设计与实施,评判其项目... 详细信息

企业数字化学习与员工发展相结合,将会极大提高员工的学习积极性。发展企业数字化学习需要与企业人力资源政策相结合。本文以案例研究法,在深入实践调研的基础上,分析了中国电信的"大规模在线岗位技能认证"项目的设计与实施,评判其项目效果。并结合中国电信的企业背景和文化特殊性,总结其成功策略,推广其最佳实践,为其它企业的数字化学习提供借鉴与参考。

关键词：岗位技能认证中国电信企业数字化学习案例研究

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高光学纯度乳酸菌株的筛选及发酵性能研究

食品与发酵工业 2024年第7期50卷 24-31页

作者：刘兰李鹏王通黄筱萍江西省科学院微生物研究所江西南昌330096

从不同地区的土壤、泡菜中分离筛选出了2株高光学纯度D-乳酸菌株和2株高光学纯度L-乳酸菌株。通过形态学观察、生理生化鉴定和16S rDNA序列分析,确定L-乳酸产生菌HA7-5菌株为屎肠球菌(Enterococcus faecium),HJ57菌株为格氏乳球菌(Lacto... 详细信息

从不同地区的土壤、泡菜中分离筛选出了2株高光学纯度D-乳酸菌株和2株高光学纯度L-乳酸菌株。通过形态学观察、生理生化鉴定和16S rDNA序列分析,确定L-乳酸产生菌HA7-5菌株为屎肠球菌(Enterococcus faecium),HJ57菌株为格氏乳球菌(Lactococcus garvieae);D-乳酸产生菌HB49-2菌株为德氏乳杆菌(Lactobacillus delbrueckii),HL64-1菌株为假肠膜明串株菌(Leuconostoc pseudomesenteroides)。经摇瓶发酵产酸培养,菌株HA7-5和HJ57发酵产L-乳酸分别达71.83 g/L和31.89 g/L;菌株HB49-2和HL64-1发酵产D-乳酸分别达73.14 g/L和62.04 g/L,且菌株HL64-1发酵周期仅为24 h,产酸速率快,平均产酸速率为2.58 g/(L·h)。D体和L体光学纯度均达99.8%(ee)以上。以上菌株均为产高光学纯度L-或D-乳酸野生型菌株,可作为后期诱变育种的出发菌株,进行菌株改良及发酵性能提升的研究。

关键词：乳酸菌分离鉴定高光学纯度乳酸发酵

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80t钢包精炼炉(LF)埋弧渣工艺分析

特殊钢 2001年第6期22卷 42-44页

作者：徐恩义童小平湘潭钢铁集团有限公司第二炼钢厂湘潭411101

叙述了湘潭钢铁公司第二炼钢厂 80t钢包精炼炉埋弧渣的成渣过程 ,并对应用埋弧渣的工艺条件和钢包精炼炉的电气特性进行了分析。

关键词：成渣电热特性埋弧渣钢包精炼炉炼钢