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Genetic optimization of ladle scheduling in empty-ladle operation stage based on temperature drop control

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Journal of Iron and Steel Research International 2022年第4期29卷 563-574页

作者： Yu-jie Hong Qing Liu Jian-ping Yang Jian Wang shan gao Hong-hui Li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Laiwu Iron and Steel Group Yinshan Section Steel Co.Ltd.Laiwu 271100ShandongChina

To optimize ladle scheduling in the empty-ladle operation stage of steel plants,a mathematical scheduling model was established for the empty-ladle operation stage,taking the minimum total waiting time in the empty-ladle operation stage as the optimization goal and setting the equipment assignment uniqueness as the key *** improved genetic algorithm was designed to calculate the mathematical scheduling *** the operation of the genetic algorithm,the strategy of"ladle temperature drop control"was adopted to solve the problem of equipment conflicts and reduce unreasonable ladle temperature drops to enhance"red-ladle"*** main production modes operating at 95%capacity in a Chinese steel plant were simulated using the genetic optimization *** results showed that the genetic optimization model could improve the efficiency of ladle operation and reduce the total waiting time in the empty-ladle operation stage by 868–1147 min.

关键词： Ladle scheduling Empty-ladle operation Waiting time Genetic algorithm Temperature drop

Review of High-Precision Sr Isotope Analyses of Low-Sr Geological Samples

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Journal of Earth Science 2015年第5期26卷 763-774页

作者： Jie Lin Yongsheng Liu Haihong Chen Lian Zhou Zhaochu Hu shan gao State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Isotope plays an important role in both tracing and dating in earth science, especially 87Rb-86 Sr system. With the development of earth science, whole-rock analysis can＇t sufficiently meet the requirements for scientific research and the micro-analysis becomes more and more significant. Laser ablation multi-collector inductively-coupled plasma mass-spectrometry（LA-MC-ICP-MS） has been extensively applied in micro-zone analysis due to its low sample-consumption, high accuracy, in situ and low requirements on matrix, but it is still difficult to accurately measure Sr isotope compositions especially for the samples with high Rb/Sr ratios and low Sr contents as it is restricted by severe quality discrimination and various types of mass spectrum interferences. Consequently, thermal ionization mass-spectrometry（TIMS）, as the most accurate and precise method to analyze isotopic ratios, is still the most popular method of analyzing Sr ratios, especially for the samples with low Sr contents. This paper makes a systematic review on the high-precision Sr isotope analyses of low-Sr geological samples, including the micro-sampling technique, ultra-low procedural blank chemical method and TIMS measurement technique. The combination of ultra-low procedural blank and TIMS can be used to perform high-precision micro-analysis of the samples with ng magnitude, which will be undoubtedly an important direction for Rb-Sr geochronology, geochemistry and environmental studies.

关键词： Sr isotope compositions Ultra-low procedural blank TIMS Micro-sampling Sr-specific resin Micro-ion exchange column

Age-Triggered and Dark-Induced Leaf Senescence Require the bHLH Transcription Factors PIF3, 4, and 5

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Molecular Plant 2014年第12期7卷 1776-1787页

作者： Yi Song Chuangwei Yang shan gao Wei Zhang Lin Li Benke Kuai State Key Laboratory of Genetic Engineering Institute of Plant Biology School of Life Sciences Fudan University Shanghai 200433People's Republic of China National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (shanghai) Institute of PlantPhysiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 People's Republic of China

Leaf senescence can be triggered and promoted by a large number of developmental and environmental fac- tors. Numerous lines of evidence have suggested an involvement of phytochromes in the regulation of leaf senescence, but the related signaling pathways and physiological mechanisms are poorly understood. In this study, we initially identi- fied phytochrome-interacting factors （PIFs） 3, 4, and 5 as putative mediators of leaf senescence. Mutations of the PIF genes resulted in a significantly enhanced leaf longevity in age-triggered and dark-induced senescence, whereas overexpressions of these genes accelerated age-triggered and dark-induced senescence in Arabidopsis. Consistently, loss-of-function of PIF4 attenuated dark-induced transcriptional changes associated with chloroplast deterioration and reactive oxygen species （ROS） generation. ChlP-PCR and DualoLuciferase assays demonstrated that PIF4 can activate chlorophyll degradation regulatory gene NYE1 and repress chloroplast activity maintainer gene GLK2 by binding to their promoter regions. Finally, dark-induced ethylene biosynthesis and ethylene-induced senescence were both dampened in pif4, suggesting the involvement of PIF4 in both ethylene biosynthesis and signaling pathway. Our study provides evidence that PIF3, 4, and 5 are novel positive senes- cence mediators and gains an insight into the mechanism of light signaling involved in the regulation of leaf senescence.

关键词： phytochrome-interacting factor (PIF) leaf senescence chloroplast deterioration NYEI/SGR1 GLK2 ethylene.

Preliminary Mo isotope data of Phanerozoic clastic sediments from the northern margin of the Yangtze block and its implication for paleoenvironmental conditions

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Chinese Science Bulletin 2009年第5期54卷 822-829页

作者： ZHOU Lian gao shan CHRIS Hawkesworth COREY Archer XIE ShuCheng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Department of Earth Sciences University of Bristol Bristol BS8 1R J U.K.

Mo isotopes along with Nd isotopes and other geochemical characteristics of the Phanerozoic clastic sediments from the northern margin of the Yangtze block were analyzed by MC-ICP-MS and some other techniques, spanning the period from Cambrian to Jurassic. The δ 98Mo values and εNd(t ) in these sedimets were observed to exhibit a large range of variation (?0.65‰―+1.87‰, ?1.46―?10.90, respec-tively). Specifically, the sample from Late Permian Maokou Formation has relatively positive values in both δ 98Mo and εNd(t ) (+0.97‰, ?1.46, respectively). These elevated values are proposed to relate to the input of a large quantity of H2S and HS- into the contemporaneous seawater by the volcanic eruption of the Emeishan mantle plume. Introduction of these sulfide gases would cause MoO42? to be transferred into MoS24?, favoring the preferential deposition of the heavy Mo isotope as MoS24? and thus leaving a positive Mo isotope value. The sample from Late Permian Changxing Formation has a significantly elevated δ 98Mo value of +1.87‰, in association with the relatively negative εNd(t ) (?10.90) and remain the relatively higher content of both TOC and total sulfur (TS) (1.52%, 2.02%, respectively). This infers the presence of the enhanced primary productivity and high organic burial during the Changxing pe-riod. The production of a huge quantity of HS? and H2S by the sulfate-reducing reaction led to the ex-istence of the elevated seawater δ 98Mo values during the Changxing period. The preliminary Phanero-zoic data reported here allow us to propose that the Mo isotope signature preserved in reductive sediments is related to the regional tectonic settings and the associated environmental conditions, and thus the measurement of δ 98Mo promotes our understanding on the evolution of the paleoenviron-mental event in the Earth history.

关键词：钼同位素古环境显生宙长江

Mass movements in small canyons in the northeast of Baiyun deepwater area, north of the South China Sea

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Acta Oceanologica Sinica 2015年第8期34卷 35-42页

作者： LI Xishuang LIU Lejun LI Jiagang gao shan ZHOU Qingjie SU Tianyun The First Institute of Oceanography State Oceanic Administration Research Center of China National Offshore Oil Corporation

The process of mass movements and their consequent turbidity currents in large submarine canyons has been widely reported, however, little attention was paid to that in small canyons. In this paper, we document mass movements in small submarine canyons in the northeast of Baiyun deepwater area, north of the South China Sea （SCS）, and their strong effects on the evolution of the canyons based on geophysical data. Submarine canyons in the study area arrange closely below the shelf break zone which was at the depth of -500 m. Within submarine canyons, seabed surface was covered with amounts of failure scars resulted from past small-sized landslides. A complex process of mass transportation in the canyons is indicated by three directions of mass movements. Recent mass movement deposits in the canyons exhibit translucent reflections or parallel reflections which represent the brittle deformation and the plastic deformation, respectively. The area of most landslides in the canyons is less than 3 km2. The trigger mechanisms for mass movements in the study area are gravitational overloading, slope angle and weak properties of soil. Geophysical data indicate that the genesis of submarine canyons is the erosion of mass movements and consequent turbidity currents. The significant effects of mass movements on canyon are incision and sediment transportation at the erosion phases and fillings supply at the fill phases. This research will be helpful for the geological risk assessments and understanding the sediment transportation in the northern margin of the SCS.

关键词： mass movement geophysical data trigger mechanism submarine canyon north of the South China Sea

Genome-wide association study dissects the genetic bases of salt tolerance in maize seedlings

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Journal of Integrative Plant Biology 2019年第6期61卷 658-674页

作者： Xi Luo Bingcai Wang shan gao Fei Zhang William Terzaghi Mingqiu Dai National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China College of Plant Science Tarim UniversityAlaer 843300China Department of Biology Wilkes UniversityWilkes-BarrePennsylvania 18766USA

Excess salinity is a natural stress that causes crop yield losses worldwide. The genetic bases of maize salt tolerance remain largely unknown. Here we investigated the survival rates of 445 maize natural accessions after salt treatments. A skewed distribution of the salttolerant phenotypes was observed in this ***-wide association studies(GWAS) revealed 57 loci significantly associated with salt tolerance. Forty-nine candidate genes were detected from these loci. About10% of these genes were co-localized with loci from QTL mapping. Forty four percent of the candidate genes were involved in stress responses, ABA signaling,stomata division, DNA binding/transcription regulation and auxin signaling, suggesting that they are key genetic mechanisms of maize salt tolerance. Transgenic studies showed that two genes, the salt-tolerance-associatedgene 4(SAG4, GRMZM2 G077295) and SAG6(GRMZM2 G106056), which encode a protein transport protein and the double-strand break repair protein MRE11,respectively, had positive roles in plant salt tolerance,and their salt-tolerant haplotypes were revealed. The genes we identified in this study provide a list of candidate targets for further study of maize salt tolerance, and of genetic markers and materials that may be used for breeding salt-tolerance in maize.

关键词： Genome-wide association dissects tolerance

Application of altimetry data assimilation on mesoscale eddies simulation

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Science China Earth Sciences 2008年第1期51卷 142-151页

作者： gao shan WANG Fan LI MingKui CHEN YongLi YAN ChangXiang ZHU Jiang Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Mesoscale eddy plays an important role in the ocean circulation. In order to improve the simulation accuracy of the mesoscale eddies, a three-dimensional variation (3DVAR) data assimilation system called Ocean Variational Analysis System (OVALS) is coupled with a POM model to simulate the mesoscale eddies in the Northwest Pacific Ocean. In this system, the sea surface height anomaly (SSHA) data by satellite altimeters are assimilated and translated into pseudo temperature and salinity (T-S) profile data. Then, these profile data are taken as observation data to be assimilated again and produce the three-dimensional analysis T-S field. According to the characteristics of mesoscale eddy, the most appropriate assimilation parameters are set up and testified in this system. A ten years mesoscale eddies simulation and comparison experiment is made, which includes two schemes: assimilation and non-assimilation. The results of comparison between two schemes and the observation show that the simulation accuracy of the assimilation scheme is much better than that of non-assimilation, which verified that the altimetry data assimilation method can improve the simulation accuracy of the mesoscale dramatically and indicates that it is possible to use this system on the forecast of mesoscale eddies in the future.

关键词： mesoscale eddies altimetry data assimilation OVALS

Repeated modification of lithospheric mantle in the eastern North China Craton:Constraints from SHRIMP zircon U-Pb dating of dunite xenoliths in western shandong

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Chinese Science Bulletin 2012年第6期57卷 651-659页

作者： YANG DeBin XU WenLiang gao shan XU YiGang PEI FuPing College of Earth Sciences Jilin UniversityChangchun 130061China CAS Key Laboratory oflsotopic Geochronology and Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640China State Key Laboratory of Geological Processes and Mineral Resources China University ofGeosciencesWuhan 430074China

Four dunite xenoliths from the Tietonggou intrusion of western shandong,China,were subjected to SHRIMP zircon U-Pb dating to constrain timing of the North China Craton(NCC) destruction,a topic of much *** images revealed that 15 of the 18 zircon grains from the xenoliths display striped *** rest showed oscillatory growth *** the zircons had variable contents of Th(49-3569 ppm;average,885 ppm) and U(184-5398 ppm;average,1277 ppm),and variable Th/U ratios(0.15-2.04).These zircon characteristics indicate a magmatic *** zircon age data can be divided into five groups:131-145,151-164,261-280,434-452,and 500-516 *** I(131-145 Ma) is consistent with timing of formation of the Tietonggou high-Mg *** II(151-164 Ma) is similar in age to Middle-Late Jurassic magmatism in the eastern NCC,which included both mantle-derived and intensive crust-derived *** III(261-280 Ma) is similar in age to the Emeishan large igneous province,and Group IV(434-452 Ma) is similar in age to Paleozoic high-silica magmatism in the eastern *** V(500-516 Ma) may correspond to the global Pan-African *** indicate repeated modification of lithospheric mantle in the eastern NCC,and suggest that the most intensive modification occurred in the late Mesozoic(131-164 Ma).

关键词：锆石U-Pb SHRIMP 橄榄岩捕虏体华北克拉通岩石圈地幔华北东部修改鲁西

Enzymatic and chemical mapping of nucleosome distribution in purified micro- and macronuclei of the ciliated model organism, Tetrahymenathermophila

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Science China(Life Sciences) 2016年第9期59卷 909-919页

作者： Xiao Chen shan gao Yifan Liu Yuanyuan Wang Yurui Wang Weibo Song Institute of Evolution & Marine Biodiversity Ocean University of China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology Department of Pathology University of Michigan

Genomic distribution of the nucleosome, the basic unit of chromatin, contains important epigenetic information. To map nucleosome distribution in structurally and functionally differentiated micronucleus(MIC) and macronucleus(MAC) of the ciliate Tetrahymena thermophila, we have purified MIC and MAC and performed micrococcal nuclease(MNase) digestion as well as hydroxyl radical cleavage. Different factors that may affect MNase digestion were examined, to optimize mono-nucleosome production. Mono-nucleosome purity was further improved by ultracentrifugation in a sucrose gradient. As MNase concentration increased, nucleosomal DNA sizes in MIC and MAC converged on 147 bp, as expected for the nucleosome core particle. Both MNase digestion and hydroxyl radical cleavage consistently showed a nucleosome repeat length of^200 bp in MAC of Tetrahymena, supporting ~50 bp of linker DNA. Our work has systematically tested methods currently available for mapping nucleosome distribution in Tetrahymena, and provided a solid foundation for future epigenetic studies in this ciliated model organism.

关键词： nucleosome micrococcal nuclease digestion hydroxyl radical cleavage Tetrahymena micronuclei macronuclei