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Fractional Dynamics of Fluid-Conveying Pipes Made of Polymer-Like Materials

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Acta Mechanica Solida Sinica 2018年第2期31卷 243-258页

作者： Ye tang Tianzhi Yang bo Fang School of Mechanical and Automotive Engineering Anhui Polytechnic University School of Aerospace Engineering Shenyang Aerospace University Department of Mechanics Tianjin University School of Astronautics Harbin Institute of Technology

The fluid-conveying pipes made of polymer-like materials are widely applied in engineering fields. However, the fractional dynamics of fluid-solid interaction remain unknown. In this work, the fractional dynamics of the pipes subjected to the excitation of supporting foun- dation are studied. A new nonlinear, fractional-order dynamic model is presented. The method of multiple scales is adopted directly to solve the model for the case of primary resonances. Numerical results are presented to show the effects of fractional order, foundation vibration, and other physical parameters on the steady-state response and stability.

关键词： Fluid-conveying pipes Fractional dynamics Method of multiple scales Polymer- like materials

The impact of regulatory and financial discrimination on China's low-carbon development:Considering firm heterogeneity

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Advances in Climate Change Research 2020年第2期11卷 72-84页

作者： tang Wei-Qi MENG bo WU Li-bo CIB Research Shanghai200120China Center for Energy Economics and Strategy Studies Fudan UniversityShanghai200433China Institute of Developing Economies–JETRO Chiba2618545Japan Tokyo Foundation for Policy Research Tokyo1066234Japan School of Economics Fudan UniversityShanghai200433China

Firms in China within the same industry but with different ownership and size have different production functions and face different emission regulations and financial conditions,thus can give very different responses to environmental *** fact has been largely ignored in most of the low-carbon development related *** an augmented Chinese input–output table in which information about firm size(large-and small and medium-sized firms)and ownership(state-,foreign-,and private-owned firms)are explicitly reported,a dynamic computable general equilibrium model is developed in this study to analyze the impact of alternative low-carbon policy designs with different regulatory coverage and financial equalization on heterogeneous *** simulation results show that,with the fully balanced regulation coverage and equalized financial system for heterogeneous firms,the total green investment accounts for 4%of GDP in 2030 for fulfilling China's commitment to reduce carbon emissions,which is the lowest among the various scenarios;about one-third of this investment is made by small and private firms;at the same time,green investment efficiency will be the highest,about 84%higher than that of the business-as-usual ***,a market-oriented and new technology-driven arrangement and mechanism for sharing emission reduction burden and allocating green investment across heterogeneous firms,especially to small and medium-sized firms,is crucial for China to achieve a more ambitious emission target in the long run.

关键词： Small-and medium-sized enterprise(SME) Green finance Firm heterogeneity ETS CO2 emissions Low-carbon Chinese economy

Molecular Population Genetics of Rice Domestication

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Journal of Integrative Plant Biology 2007年第6期49卷 769-775页

作者： Tian tang Suhua shi State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-sen (Zhongshan) University Guangzhou 510275 China

Domestication is a selection process that genetically modifies species to meet human needs. A most intriguing feature of domestication is the extreme phenotypic diversification among breeds. What could be the ultimate source of such genetic variations？ Another notable outcome of artificial selection is the reduction In the fitness of domesticated species when they live In the wild without human assistance. The complete sequences of the two subspecies of rice cultlvars provide an opportunity to address these questions. Between the two subspecies, we found much higher rates of non-synonymous （N） than synonymous （S） substitutions and the N/S ratios are higher between cultivars than between wild species. Most interestingly, substitutions of highly dissimilar amino acids that are deleterious and uncommon between natural species are disproportionately common between the two subspecies of rice. We suggest strong selection in the absence of effective recombination may be the driving force, which we called the domestication-associated Hill-Robertson effect. These hitchhiking mutations may contribute to some fitness reduction in cultivars. Comparisons of the two genomes also reveal the existence of highly divergent regions in the genomes. Haplotypes in these regions often form highly polymorphic linkage blocks that are much older than speciation between wild species. Genes from such regions could contribute to the differences between indica and japonica and are likely to be involved in the diversifying selection under domestication. Their existence suggests that the amount of genetic variation within the single progenitor species Oryza rufipogon may be insufficient to account for the variation among rice cultivars, which may come from a more inclusive gene pool comprising most of the A-genome wild species. Genes from the highly polymorphic regions also provide strong support for the Independent domestication of the two subspecies. The genomic variation in rice has revealing i

关键词： rice population genetics domestication artificial selection admixture.

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang Bing Zhang Lanfang Li Xiaomei tang Jinyu Zeng Yige Song Chao Xu Kai Zhao Guoqiang Liu Youming Lu Xinyan Li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Green Monomer of CO_(2) and Alkyne-based Four-component Tandem Polymerization toward Regio-and Stereoregular Poly(aminoacrylate)s

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Chinese Journal of Polymer Science 2021年第1期39卷 51-59,I0006页

作者： bo Song An-Jun Qin Ben Zhong tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesCenter for Aggregation-Induced EmissionSouth China University of TechnologyGuangzhou 510640China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration and ReconstructionInstitute for Advanced StudyDepartment of Chemical and Biological EngineeringThe Hong Kong University of Science&TechnologyHong KongChina

Green monomers, such as carbon dioxide(CO_(2)), are closely related to our daily life and highly desirable to be transferred to functional polymers with diverse structures and versatile properties because they are abundant, cheap, nontoxic, renewable, and sustainable. However, the polymerizations based on these green monomers are to be further developed. In this work, a facile CO_(2) and alkyne-based one-pot, two-step, fourcomponent tandem polymerization was successfully established. The polymerization of CO_(2), diynes, alkyl dihalides, and primary/secondary amines can proceed under mild reaction conditions and regio-and stereoregular poly(aminoacrylate)s with good solubility and thermal stability were obtained in high yields(up to 95%). Notably, distinctly different stereoregularity of resultant poly(aminoacrylate)s was realized via using primary or secondary amines. Using the former would readily generate polymers with 100% Z-isomers, whereas the latter furnished products with over 95% E-isomers. Through different monomer combination, the polymers with tunable structures and properties were ***, the tetraphenylethene units containing poly(aminoacrylate)s, showing the unique aggregation-induced emission characteristics,could function as a fluorescent probe for sensitive explosive detection. Thus, this work not only develops a facile CO_(2) and alkyne-based multicomponent tandem polymerization but also provides a valuable strategy to fine-tune the polymer structures and properties, which could be potentially applied in diverse areas.

关键词： Carbon dioxide Multicomponent tandem polymerization Aggregation-induced emission Green monomer

Advanced delivery strategies facilitating oral absorption of heparins

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Asian Journal of Pharmaceutical Sciences 2020年第4期15卷 449-460页

作者： Guihua Fang bo tang School of Pharmacy Nantong University19 Qixiu RoadNantong 226001China

Heparins show great anticoagulant effect with few side effects,and are administered by subcutaneous or intravenous route in *** improve patient compliance,oral administration is an alternative ***,oral administration of heparins still faces enormous challenges due to the multiple *** review briefly analyzes a series of barriers ranging from poorly physicochemical properties of heparins,to harsh biological barriers including gastrointestinal degradation and pre-systemic ***,several approaches have been developed to overcome these obstacles,such as improving stability of heparins in the gastrointestinal tract,enhancing the intestinal epithelia permeability and facilitating lymphatic delivery of ***,this review aims to provide insights concerning advanced delivery strategies facilitating oral absorption of heparins.

关键词： Heparins Oral delivery Multiple obstacles Stability Intestinal epithelia permeability Lymphatic transport

Effects of Structural Parameters on the Poisson’s Ratio and Compressive Modulus of 2D Pentamode Structures Fabricated by Selective Laser Melting

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Engineering 2020年第1期6卷 56-67页

作者： Lei Zhang bo Song Ruijie Liu Aiguo Zhao Jinliang Zhang Linrong Zhuo Guiping tang Yusheng shi State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan 430074China Wuhan Second ship Design and Research Institute Wuhan 430064China

Metamaterials have been receiving an increasing amount of interest in recent years. As a type of metamaterial, pentamode materials (PMs) approximate the elastic properties of liquids. In this study, a finite-element analysis was conducted to predict the mechanical properties of PM structures by altering the thin wall thicknesses and layer numbers to obtain an outstanding load-bearing capacity. It was found that as the thin wall thickness increased from 0.15 to 0.45 mm, the compressive modulus of the PM structures increased and the Poisson’s ratio decreased. As the layer number increased, the Poisson’s ratio of the PM structures increased rapidly and reaches a stable value ranging from 0.50 to 0.55. Simulation results of the stress distribution in the PM structures confirmed that stress concentrations exist at the junctions of the thin walls and weights. For validation, Ti–6Al–4V specimens were fabricated by selective laser melting (SLM), and the mechanical properties of these specimens (i.e., Poisson’s ratio and elastic modulus) were experimentally studied. Good consistency was achieved between the numerical and experimental results. This work is beneficial for the design and development of PM structures with simultaneous load-bearing capacity and pentamodal properties.

关键词： Metamaterials Pentamode materials Finite-element analysis Selective laser melting

Reductive smelting of spent lead–acid battery colloid sludge in a molten Na_2CO_3 salt

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 798-803页

作者： Yu-jie Hu Chao-bo tang Mo-tang tang Yong-ming Chen School of Metallurgy and Environment Central South University School of Metallurgy Engineering Hunan University of Technology

Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing Zn O as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, Zn O and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows: T = 880°C; t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the Zn O dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The results suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic calculations indicated that the reaction approaches of lead and sulfur were Pb SO4→Pb and Pb SO4→Zn S, respectively. Sulfur was fixed in the form of Zn S, whereas the molten salt did not react with other components, serving only as a reaction medium.

关键词： lead–acid batteries molten salts lead smelting des

Enhanced autophagic clearance of amyloid-βvia histone deacetylase 6-mediated V-ATPase assembly and lysosomal acidification protects against Alzheimer's disease in vitro and in vivo

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Neural Regeneration Research 2025年第9期20卷 2633-2644页

作者： Zhimin Long Chuanhua Ge Yueyang Zhao Yuanjie Liu Qinghua Zeng Qing tang Zhifang Dong Guiqiong He Institute of Neuroscience School of Basic Medical SciencesChongqing Medical UniversityChongqingChina Department of Anatomy Chongqing Medical UniversityChongqingChina Department of Physiology Chongqing Medical UniversityChongqingChina Pediatric Research Institute Children’s Hospital of Chongqing Medical UniversityChongqingChina Ministry of Education Key Laboratory of Child Development and Disorders Children’s Hospital of Chongqing Medical UniversityChongqingChina National Clinical Research Center for Child Health and Disorders Children’s Hospital of Chongqing Medical UniversityChongqingChina Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders Children’s Hospital of Chongqing Medical UniversityChongqingChina

Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-βin neurons,which is a key step in senile plaque ***,resto ring normal lysosomal function and rebalancing lysosomal acidification in neurons in the brain may be a new treatment strategy for Alzheimer's *** acetylation/deacetylation plays a central role in lysosomal ***,we show that inhibiting the classic microtubule deacetylase histone deacetylase 6 with an histone deacetylase 6 shRNA or thehistone deacetylase 6 inhibitor valproic acid promoted lysosomal reacidification by modulating V-ATPase assembly in Alzheimer's *** rthermore,we found that treatment with valproic acid markedly enhanced *** clearance of amyloid-βaggregates,and ameliorated cognitive deficits in a mouse model of Alzheimer's *** findings demonstrate a previously unknown neuroprotective mechanism in Alzheimer's disease,in which histone deacetylase 6 inhibition by valproic acid increases V-ATPase assembly and lysosomal acidification.

关键词： Alzheimer's disease amyloid-β APP/PS1 mice autophagy cognitive impairment histone deacetylase 6 lysosomal acidification microtubule acetylation valproic acid V-ATPase