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Organic Carbon in the surface sediments from the Intensive Mariculture Zone of sanggou Bay: Distribution, seasonal Variations and sources

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journal of Ocean University of China 2019年第4期18卷 985-996页

作者： sUI juanjuan ZHANG jihong REN s. jeffrey LIN fan Yellow sea Fisheries Research Institute Chinese Academy of Fishery Sciences Qingdao 266071 China Function Laboratory for Marine Fisheries science and Food Production Processes Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China Function Laboratory for Marine Fisheries science and Food Production Processes Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China

Mariculture has rapidly grown worldwide, which might greatly influence the biogeochemical cycle of organic carbon in coastal seas. In this study, several geochemical parameters, including grain size composition, sedimentary total organic carbon (TOC), total nitrogen (TN), stable carbon (δ13C) and nitrogen (δ15N) isotopic compositions, were analyzed for surface sediments collected from different mariculture zones of sanggou Bay and in different seasons. We investigated the composition and distribution of or- ganic matter in surface sediments and further evaluated the contribution of mariculture activities to TOC sources. The TOC and TN contents (mass percentage) in the bay were in the range of 0.14% to 1.45% and 0.03% to 0.20%, respectively. The spatial distribution indicated that sedimentary TOC and TN contents in shellfish monoculture and shellfish-kelp polyculture zones were higher than in other mariculture zones, which might be related to grain size composition and mariculture organisms. seasonal variations of TOC contents were observed in different mariculture zones. The TOC/TN atomic ratio (C/N),δ13C and δ15N were in the ranges of 5.97 to 10.97, 21.76‰ to 13.14‰ and 2.13‰ to 8.08‰, respectively, implying that sedimentary organic matter in sanggou Bay was the mixture of marine phytoplankton, terrestrial and maricultural sources. A simple mixing model based on δ13C was applied and the results indicated that the relative contributions of organic carbon sources in sanggou Bay followed the order kelp (36.6%) marine phytoplankton (28.7%) shellfish bio-deposition (23.8%) terrestrial input (10.9%). surface sediments in sanggou Bay were domi- nated by mariculture-derived organic carbon, which on average accounted for 60.4% of TOC.

关键词： sediment organic carbon sources mariculture sanggou Bay Iso-source

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碳纳米管改性混凝土的应力应变与动态强度研究

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合成纤维 2025年第1期54卷 86-90页

作者：范宝宝中煤科工集团北京华宇工程有限公司北京100120

为深入探究碳纳米管(CNTs)对混凝土不同受力阶段的增强效果,利用100 mm直径的分离式霍普金森压杆试验,研究冲击速度、CNTs含量等因素对混凝土韧性和抗冲击性能的影响。试验结果表明:CNTs的加入对水泥基材料的冲击性能有显著的改善作用,... 详细信息

为深入探究碳纳米管(CNTs)对混凝土不同受力阶段的增强效果,利用100 mm直径的分离式霍普金森压杆试验,研究冲击速度、CNTs含量等因素对混凝土韧性和抗冲击性能的影响。试验结果表明:CNTs的加入对水泥基材料的冲击性能有显著的改善作用,动态抗压强度、动态强度增大因子随冲击速度的增加而呈直线上升;在同一加载程度下,随CNTs含量的增大,水泥基材料的动态抗压强度先增大后减小,最大增幅可达23.7%;在混凝土中加入适量的CNTs,能够提高混凝土的整体强度、致密性,进而提高其动态力学性能。

关键词：碳纳米管混凝土霍普金森压杆应力应变动态强度

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Pharmacological targeting cGAs/sTING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3287-3301页

作者： Ziwei fan Mengxian jia jian Zhou Zhoule Zhu Yumin Wu Xiaowu Lin Yiming Qian jiashu Lian Xin Hua jianhong Dong Zheyu fang Yuqing Liu sibing Chen Xiumin Xue juanqing Yue Minyu Zhu Ying Wang Zhihui Huang Honglin Teng Department of Orthopedics(spine surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina school of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Neurology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina

The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord *** of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be *** possesses an anti-inflammatory biological ***,its roles and the underlying molecular mechanisms in spinal cord injury remain *** this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in *** promoted M2 polarization through inactivating the cGAs/sTING/NF-κB ***,we found that targeting the cGAs/sTING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord ***,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal *** together,these results suggest that by targeting the cGAs/sTING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype.

关键词： cGAs/sTING functional recovery microglia neuroinflammation neuroprotection nuclear factor-κB polarization spinal cord injury tryptanthrin

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Touristic urbanization and greening of coastal dune fields:A long-term assessment of a temperate sandy barrier of Argentina

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journal of Geographical sciences 2025年第1期35卷 206-230页

作者： GARZO Pedro Andrés DADON josé Roberto IsLA Federico Ignacio Instituto de Investigaciones Marinas y Costeras (IIMyC-CONICET/UNMDP) Instituto de Geología de Costas y del Cuaternario Dr.Enrique j.schnack (IGCC-CIC/UNMDP) Universidad de Buenos Aires Facultad de Arquitectura Dise?o y Urbanismo Centro de Investigaciones Gestión de Espacios Costeros (GEC-FADU/UBA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)

Dune barrier systems represent highly sought-after coastal landscapes for tourism and urban development around the world. However, a century ago, they were considered hazardous environments due to their great dynamic nature. As a result, stabilization practices were considered necessary. The systematic introduction of fast-growing exotic trees helped stabilize the sand, making it easier for tourism urbanization to take place, but also leading to erosion processes. This paper aims to assess long-term changes in vegetation cover over a large temperate barrier in Argentina. This complex region includes urban resorts, afforestation zones, and protected areas. A GIs-based geospatial analysis was conducted using a large satellite database(> 350 images), and the future evolution of the vegetation was modeled. The results revealed two primary spatiotemporal patterns associated with a gradual expansion of vegetation cover, accompanied by a concurrent reduction in sandy areas. In 1986, the dune area comprised 75% more surface than vegetation, whereas in 2021, it represented 60% less than vegetation. Furthermore, the 2050 scenario suggests a potential 40% reduction of dunes in certain areas. It is necessary to enhance management actions aimed at maintaining dune mobility and ensuring local and regional sediment balance. Long-term management strategies must focus on restoring native plant communities and controlling invasive species, and avoiding new dune fixation initiatives based on the introduction of exotic species.

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Recent progress in NIR-Ⅱ emitting lanthanide-based nanoparticles and their biological applications

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journal of Rare Earths 2020年第5期38卷 451-463页

作者： suwan Ding Lingfei Lu Yong fan fan Zhang Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsState Key Laboratory of Molecular Engineering of Polymers and iChemFudan UniversityShanghai 200433China

The second near-infrared(NIR-Ⅱ,1000-1700 nm)window provides a superior optical platform with high resolution,deep penetration and high signal-to-noise ratios(sNRs),which results from the intrinsic low scattering and auto fluorescence in biological *** one of the promising NIR-Ⅱemitting probes,lanthanide based nanoparticles(LnNPs)exhibit high photo stability and chemostability,long photoluminescence lifetimes,low long-term cytotoxicity and narrow emission *** these merits have spurred the evolution of related bio-optics and a variety of biomedical applications of *** mini-review discusses the most recent advances in both the design-the composition and surface modifications-and the applications of NIR-Ⅱemitting LnNPs in bioimaging,disease diagnosis and *** also summarize the current limits and challenges facing the applications of LnNPs as well as discuss the directions of future development.

关键词： Lanthanide nanoparticles second near infrared window Fluorescence imaging Diagnose Therapy Rare earths

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Computing knots by quadratic and cubic polynomial curves

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Computational Visual Media 2020年第4期6卷 417-430页

作者： fan Zhang jinjiang Li Peiqiang Liu Hui fan school of Computer science and Technology Shandong Technology and Business UniversityYantai 264005China Co-Innovation Center of shandong Colleges and Universities:Future Intelligent Computing Yantai 264005China

A new method is presented to determine parameter values(knot)for data points for curve and surface *** four adjacent data points,a quadratic polynomial curve can be determined uniquely if the four points form a convex *** the four data points do not form a convex polygon,a cubic polynomial curve with one degree of freedom is used to interpolate the four points,so that the interpolant has better shape,approximating the polygon formed by the four data *** degree of freedom is determined by minimizing the cubic coefficient of the cubic polynomial *** advantages of the new method are,firstly,the knots computed have quadratic polynomial precision,i.e.,if the data points are sampled from a quadratic polynomial curve,and the knots are used to construct a quadratic polynomial,it reproduces the original quadratic ***,the new method is affine invariant,which is significant,as most parameterization methods do not have this ***,it computes knots using a local *** show that curves constructed using knots computed by the new method have better interpolation precision than for existing methods.

关键词： knot interpolation polynomial curve affine invariant

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ALLOYING EFFECT OF Ni AND Cr ON THE WETTABILITY OF COPPER ON W sUBsTRATE

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Acta Metallurgica sinica(English Letters) 2008年第5期21卷 369-379页

作者： X.H. Yang P. Xiao s.H. Liang j.T. Zou Z.K. fan shaanxi Key Laboratory for Electrical Materials and Infiltration Technology School of Materials Science and Engineering Xi＇an University of Technology Xi＇an 710048 China

By the sessile drop technique, the wettability of Cu/W systems with the additions of Ni and Cr has been studied under vacuum atmosphere. Effects of Ni and Cr contents and wetting temperatures on the wettability and the wetting mechanisms of copper on W substrate have been investigated in detail. The results show that the wetting angles of Cu on the W substrate are decreased with an increase in the content of Ni or Cr, and also decrease with raising the wetting temperatures. sEM, EPMA, and X-ray diffraction have been used to analyze the interracial characteristics of the CuNi/W and CuCr/W systems. The results reveal that there is a transition layer about 2- 3μm in the interface of Cu-4.0 wt pct Ni/W, in which the interrnetallic phase Ni4W is precipitated. As to CuCr/W system, no reaction occurs at the interface. The two factors are that the contents of Cr and Ni and the infiltration temperature must be chosen appropriately in order to control the interfacial dissolution and reaction when the Cu- W alloys are prepared by the infiltration method.

关键词： Wettability Contact angles Cu, Cr, Ni W substrate

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Compressive elastic behavior of single-crystalline 4H-silicon carbide(siC) nanopillars

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science China(Technological sciences) 2021年第1期64卷 37-43页

作者： fan suFeng LI XiaoCui fan Rong LU Yang Department of Mechanical Engineering City University of Hong KongHong Kong 999077China Department of Materials science and Engineering City University of Hong KongHong Kong 999077China Nanomanufacturing Laboratory(NML) Center for Advanced Structural Materials(CASM)City University of Hong Kong Shenzhen Research InstituteShenzhen 518057China

As a wide-bandgap semiconductor, 4H-siC is an ideal material for high-power and high-frequency devices, and plays an increasingly important role in developing our country’s future electric vehicles and 5G techniques. Practical applications of siCbased devices largely depend on their mechanical performance and reliability at the micro-and nanoscales. In this paper, singlecrystal [0001]-oriented 4H-siC nanopillars with the diameter ranging from ~200 to 700 nm were microfabricated and then characterized by in situ nanomechanical testing under sEM/TEM at room temperature. Loading-unloading compression tests were performed, and large, fully reversible elastic strain up to ~6.2% was found in nanosized pillars. Brittle fracture still occurred when the max strain reached ~7%, with corresponding compressive strength above 30 GPa, while in situ TEM observation showed few dislocations activated during compression along the [0001] direction. Besides robust microelectromechanical system(MEMs), flexible device and nanocomposite applications, the obtained large elasticity in [0001]-oriented 4H-siC nanopillars can offer a fertile opportunity to modulate their electron mobility and bandgap structure by nanomechanical straining,the so called "elastic strain engineering", for novel electronic and optoelectronic applications.

关键词： silicon carbide elastic deformation compressive behavior in situ sEM/TEM elastic strain engineering

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sIMULATION OF THE CHANGE OF sINTERING NECK BETWEEN TWO GRAINs IN TWO DIMENsIONs

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Acta Metallurgica sinica(English Letters) 2006年第6期19卷 397-404页

作者： Y.Y.Zhu s.H.Liang Z.j.Zhan P.Xiao Z.K.fan school of Materials science and Engineering Xi’an University of TechnologyXi’an 710048China

A modified two-sphere model of sintering neck has been proposed, wherein three diffusion mechanisms including surface diffusion, grain-boundary diffusion and coupled surface and grain-boundary diffusion are assumed. sintering neck is appropriately simulated using the modified model. The dynamic change of sintering neck is presented using the simulation. The variational shape of sintering neck in surface diffusion mechanism is continuous, whereas in grain-boundary diffusion mechanism, besides the variational shape of sintering neck being continuous, the center distance between the particles is also assumed to contract. However, the variational shape of sintering neck in coupling diffusion mechanism is integrated using the two diffusion mechanisms mentioned above.

关键词： sintering simulation neck growth surface diffusion grain-boundary diffusion

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spatial identification and scenario simulation of the ecological transition zones under the climate change in China

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journal of Geographical sciences 2021年第4期31卷 497-517页

作者： fan Zemeng state Key Laboratory of Resources and Environmental Information system Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Explicitly identifying the spatial distribution of ecological transition zones(ETZs)and simulating their response to climate scenarios is of significance in understanding the response and feedback of ecosystems to global climate *** this study,a quantitative spatial identification method was developed to assess ETZ distribution in terms of the improved Holdridge life zone(iHLZ)*** on climate observations collected from 782 weather stations in China in the T0(1981–2010)period,and the Intergovernmental Panel on Climate Change Coupled Model Intercomparison Project(IPCC CMIP5)RCP2.6,RCP4.5,and RCP8.5 climate scenario data in the T1(2011–2040),T2(2041–2070),and T3(2071–2100)periods,the spatial distribution of ETZs and their response to climate scenarios in China were simulated in the four periods of T0,T1,T2,and ***,a spatial shift of mean center model was developed to quantitatively calculate the shift direction and distance of each ETZ type during the periods from T0 to *** simulated results revealed 41 ETZ types in China,accounting for 18%of the whole land *** temperate grassland/humid forest and warm temperate arid forest(564,238.5 km~2),cold temperate humid forest and warm temperate arid/humid forest(566,549.75 km~2),and north humid/humid forest and cold temperate humid forest(525,750.25 km~2)were the main ETZ types,accounting for 35%of the total ETZ area in *** 2010 and 2100,the area of cold temperate desert shrub and warm temperate desert shrub/thorn steppe ETZs were projected to increase at a rate of 4%per decade,which represented an increase of 3604.2,10063.1,and 17,242 km~2 per decade under the RCP2.6,RCP4.5,and RCP8.5 scenarios,*** cold ETZ was projected to transform to the warm humid ETZ in the *** average shift distance of the mean center in the north wet forest and cold temperate desert shrub/thorn grassland ETZs was generally larger than that of other ETZs,with the mean center moving to the n

关键词： ecological transition zone mean center spatial identification model scenario simulation China

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