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A Theoretical Study on the Stereoisomerism in the Complex of Cucurbit[8]uril with 2,6-Bis(4,5-dihydro-1H-imidazol-2-yl)naphthalene

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Chinese Chemical Letters 2001年第9期12卷 783-786页

作者： Ting Wei mu Lei LIU Ke Chun ZHANG qing Xiang GUO Department of Chemistry University of Science and Technology of ChinaHefei 230026

Semiempirical PM3 and density function theory B3LYP/3-21g* calculations in vacuum and in water indicated that the 'syn' orientation was preferred in the 1:2 complex of cucurbit[8]uril with protonated 2, 6-bis(4, 5-dihydro-1H-imidazol-2-yl)naphthalene. The pi-pi stacking interaction between the two substrate molecules was proposed as the physical origin of such a behavior.

关键词： Cucurbiturils inclusion complexation PM3 B3LYP pi-pi stacking

Influence of correlation scale errors on aquifer hydraulic conductivity inversion precision

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Water Science and Engineering 2020年第3期13卷 243-252页

作者： Yun-xiao mu Lei Zhu Tong-qing Shen Meng Zhang Yuan-yuan Zha School of Civil Engineering and Water Conservancy Ningxia UniversityYinchuan 750021China Engineering Research Center for Efficient Utilization of Modern Agricultural Water Resources in Arid Regions Ministry of EducationYinchuan 750021China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

In order to investigate the influence of correlation scale error on the inversion precision of the hydraulic conductivity of the aquifer,the successive linear estimator(SLE)was used to invert the hydraulic conductivity field of a heterogeneous aquifer based on synthetic *** increasing the numbers of observation wells and pumping tests,we analyzed the difference between the estimated and true values of hydraulic conductivity with different correlation scale *** relationships between the observation well number and the error in inversion results,and between the pumping test number and the error in inversion results were *** results show that,if the amount of observed head data is insufficient,there will be errors in inversion results with changing correlation *** to the existence of correlation scale error,the improvement of inversion precision gradually slows down with the increase of the amount of observed head data,which indicates that too much observed head data causes data ***,for the synthetic experiments described in this paper,the observation well number should be less than 41,the pumping test number should be less than 17,and a more suitable method should be selected according to the precision requirements of specific situations in practical engineering.

关键词： Hydraulic conductivity Parameter inversion Successive linear estimator Correlation scale error Observation well number Pumping test number

Sacral chondroblastoma — a rare location, a rare pathology: A case report and review of literature

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World Journal of Clinical Cases 2021年第20期9卷 5709-5716页

作者： Bo-Wen Zheng Hua-qing niu Xiao-Bin Wang Jing Li Department of Spine Surgery The Second Xiangya HospitalCentral South UniversityChangsha 410011Hunan ProvinceChina Department of Orthopedics Surgery General Hospital of the Central Theater CommandWuhan 430061Hubei ProvinceChina

BACKGROUND Chondroblastoma(CB)is an intermediate tumor of cartilage *** involving the sacrum is a very rare *** SUMMARY A 17-year-old male with sacral CB was diagnosed as CB during the first surgery,and 18 mo later,the tumor recurred and a second surgery was performed with the same pathology result of *** We recommend complete removal of the tumor in a timely manner,provided that surgical conditions are *** the same time,other diseases should be carefully differentiated in terms of imaging or pathological features so as to avoid erroneous diagnostic conclusions.

关键词： Sacrum Chondroblastoma Spine Pathology Immunohistochemistry Case report

Possibility of reaching the predicted center of the“island of stability”via the radioactive beam-induced fusion reactions

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Nuclear Science and Techniques 2024年第9期35卷 186-195页

作者： Ming-Hao Zhang Ying Zou Mei-Chen Wang Gen Zhang qing-Lin niu Feng-Shou Zhang The Key Laboratory of Beam Technology of Ministry of Education School of Physics and AstronomyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of LanzhouLanzhou 730000China

Based on the dinuclear system model,the synthesis of the predicted double-magic nuclei^(298)Fl and 304120 was investigated via neutron-rich radioactive beam-induced fusion *** reaction^(58)Ca+^(244)Pu is predicted to be favorable for producing^(298)Fl with a maximal ER cross section of 0.301 *** of the entrance channel effect reveal that the^(244)Pu target is more promising for synthesizing^(298)Fl than the neutron-rich targets^(248)Cm and^(249)Bk,because of the influence of the Coulomb *** the synthesis of 304120,the maximal ER cross section of 0.046 fb emerges in the reaction^(58)V+^(249)Bk,indicating the need for further advancements in both experimental facilities and reaction mechanisms.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Double-magic nucleus Radioactive beam

Application of machine learning models in groundwater quality assessment and prediction:progress and challenges

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 25-55页

作者： Yanpeng Huang Chao Wang Yuanhao Wang Guangfeng Lyu Sijie Lin Weijiang Liu Haobo niu qing Hu School of Environment Harbin Institute of TechnologyHarbin 150090China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Engineering Innovation Center of SUSTech(Beijing) Southern University of Science and TechnologyBeijing 100083China Technical Center for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China Chinese Academy of Environmental Planning Beijing 100043China

Groundwater quality assessment and prediction(GQAP)is vital for protecting groundwater *** GQAP methods can not adequately capture the complex relationships among attributes and have the disadvantage of being computationally ***,the application of machine learning(ML)in GAQP(GQAPxML)has been widely studied due to ML’s reliability and *** many GQAPxML publications exist,a thorough review is *** review provides a comprehensive summary of the development of ML applications in the field of ***,the workflow of ML modeling is briefly introduced,as are data preparation,model development,model evaluation,and model ***,299 publications related to the topic are filtered,mainly through ML ***,many aspects of GQAPxML,such as publication trends,the spatial distribution of study areas,the size of data sets,and ML algorithms,are discussed from a bibliometric *** addition,we review in detail the well-established applications and recent findings for several subtopics,including groundwater quality assessment,groundwater quality modeling using groundwater quality parameters,groundwater quality spatial mapping,probability estimation of exceeding the groundwater quality threshold,groundwater quality temporal prediction,and the hybrid use of ML and physics-based ***,the development of GQAPxML is explored from three perspectives:data collection and preprocessing,model building and evaluation,and the broadening of model *** review provides a reference for environmental scientists to better understand GQAPxML and promotes the development of innovative methods and improvements in modeling quality.

关键词： Groundwater quality assessment Groundwater quality prediction Machine learning Groundwater modeling

Neural Mechanism Underlying Task-Specific Enhancement of Motor Learning by Concurrent Transcranial Direct Current Stimulation

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Neuroscience Bulletin 2023年第1期39卷 69-82页

作者： Ying Wang Jixian Wang qing-Fang Zhang Ke-Wei Xiao Liang Wang qing-Ping Yu qing Xie mu-Ming Poo Yunqing Wen Institute of Neuroscience State Key Laboratory of NeuroscienceKey Laboratory of Primate NeurobiologyCenter for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai200031China University of Chinese Academy of Sciences Beijing100049China School of Life Science and Technology ShanghaiTech UniversityShanghai201210China Department of Rehabilitation Medicine Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology Lingang LaboratoryShanghai201210China

The optimal protocol for neuromodulation by transcranial direct current stimulation(tDCS)remains *** the rotarod paradigm,we found that mouse motor learning was enhanced by anodal tDCS(3.2 mA/cm^(2))during but not before or after the performance of a ***-task experiments showed that motor learning enhancement was specific to the task accompanied by anodal *** using a mouse model of stroke induced by middle cerebral artery occlusion showed that concurrent anodal tDCS restored motor learning capability in a task-specific *** in vivo Ca^(2+)imaging further showed that anodal tDCS elevated and cathodal tDCS suppressed neuronal activity in the primary motor cortex(M1).Anodal tDCS specifically promoted the activity of task-related M1 neurons during task performance,suggesting that elevated Hebbian synaptic potentiation in task-activated circuits accounts for the motor learning ***,application of tDCS concurrent with the targeted behavioral dysfunction could be an effective approach to treating brain disorders.

关键词： Motor learning tDCS effect Neural mechanism of tDCS Neuronal excitability Stroke model mouse

Thinking process rules extraction for manufacturing process design

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Advances in Manufacturing 2017年第4期5卷 321-334页

作者： Jing-Tao Zhou Xiang-Qian Li Ming-Wei Wang Rui niu qing Xu Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Ministry of Education of ChinaNorthwestern Polytechnical University Xi'an 710072People's Republic of China Department of Software and Information Service Research Electronic Technology Information Research Institute Ministry of Industry and Information Technology of the People's Republic of China Beijing 100040 People's Republic of China

To realize the reuse of process design knowledge and improve the efficiency and quality of process design, a method for extracting thinking process rules for process design is proposed. An instance representation model of the process planning reflecting the thinking process of techni- cians is established to achieve an effective representation of the process documents. The related process attributes are extracted from the model to form the related events. The manifold learning algorithm and clustering analysis are used to preprocess the process instance data. A rule extraction mechanism of process design is introduced, which is based on the related events after dimension reduction and clustering, and uses the association rule mining algorithm to realize the similar process information extraction in the same cluster. Through the vectorization description of the related events, the final process design rules are formed. Finally, an example is given to evaluate the method of process design rules extraction.

关键词： Process design rules Process design rules extraction Process planning model Related event Manifold learning

Heat-stress-induced sprouting and differential gene expression in growing potato tubers: Comparative transcriptomics with that induced by postharvest sprouting

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Horticulture Research 2021年第1期8卷 3089-3106页

作者： Guodong Zhang Ruimin Tang Suyan niu Huaijun Si qing Yang Om P.Rajora Xiu-qing Li Gansu Provincial Key Laboratory of Aridland Crop Science Gansu Key Laboratory of Crop Genetic and Germplasm EnhancementGansu Agricultural UniversityLanzhouChina College of Agronomy Gansu Agricultural UniversityLanzhouChina Fredericton Research and Development Centre Agriculture and Agri-Food CanadaGovernment of CanadaFrederictonNew BrunswickCanada College of Life Sciences Nanjing Agricultural UniversityNanjingChina Institute of Bioengineering Zhengzhou Normal UniversityZhengzhouChina College of Life Science and Technology Gansu Agricultural UniversityLanzhouChina Faculty of Forestry and Environmental Management University of New BrunswickFrederictonCanada

Crops face increased risk from heat stress due to climate ***(Solanum tuberosum L.)tubers grown in hot summers often have defects including pre-harvest sprouting(“heat sprouts”).We have used 18 potato cultivars to investigate whether heat stress(HS)conditions alone could cause heat sprouting and dormancy changes in *** also examined transcriptomic responses of potato to HS and whether these responses are like those induced by postharvest *** demonstrated that HS alone caused heat sprouts and shortened postharvest dormancy period,heat-sprouted tubers became dormant after harvest,and cultivars varied substantially for producing heat spouts but there was no clear association with cultivar maturity *** Innovator did not show any heat sprouts and still had long ***-associated genes(DOG1 and SLP)were downregulated in HS tubers like in postharvest sprouting *** have identified 1201 differentially expressed genes,14 enriched GO terms and 12 enriched KEGG pathways in response to HS in growing tubers of‘Russet Burbank’.Transcriptomic response of‘Russet Burbank’to HS showed significant similarities to that of postharvest non-HS sprouted *** biosynthesis pathway was enriched in heat-stressed tubers and was likely involved in heat sprouting and dormancy *** sprouting and postharvest sprouting shared common candidate genes and had significant similarity in gene *** study has significance for selecting potato cultivars for farming,planning storage and utilization of heat-stressed tubers,identifying sprouting-related genes,understanding heat-stress biology,and breeding heat-tolerant potato cultivars,especially for sustainable potato production under climate change.

关键词： selecting similarity stress

Syntheses, Structures, and Blue Luminescent Properties of 2,6-Bis-(benzimidazolyl) Pyridine and Its Mercury Complex

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Chemical Research in Chinese Universities 2007年第2期23卷 159-162页

作者： LIU Xiao-ming mu Xiao-yue XIA Hong SU qing YE Ling CHEN Chao GAO Wei mu Ying Key Laboratory for Supramolecular Structure and Materials of Ministry of Education College of Chemistry Jilin University Changchun 130012 P. R. China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A novel blue luminescent mercury （ Ⅱ ） complex of 2,6-bis （benzimidazolyl） pyridine （L） was synthesized. In solid state, this complex has the formula [Hg（L）Cl2] · 2DMF（1）. The molecular structures of both the ligand and the complex were determined by using tingle-crystal X-ray diffraction. Crystallographic studies of the mercury （ Ⅱ） complex reveal that the complex possesses a five-coordinated geometry that can be best described as a distorted trigonal-bipyramidal. The luminescent properties of ligand L and complex 1 both in solution and in solid state were also studied.

关键词： 2,6-Bis (benzimidazolyl) pyridine Mercury Crystal structure Blue luminescence