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Influence of Spur Dike on Hydrodynamic Exchange Between Channel and Shoal of Generalization Estuary in Physical Model Test

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China Ocean Engineering 2017年第5期31卷 624-630页

作者： jiao zeng-xiang Dou Xi-ping ZHENG Jin-hai ZHANG Xin-zhou GAO xiang-yu Nanjing Hydraulic Research Institute College of Harbor Coastal and Offshore EngineeringHohai University Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of Transport

Widely applied in maintaining estuarial waterway depth, the spur dike has played an important role in currents and sediment exchange between channel and shoal and sediment back-silting in the channel. Through establishing a generalized physical model at a bifurcated estuary and conducting current tests under the joint action of runoff and tide, the influence of the spur dike length on current exchange between channel and shoal is analyzed. Results show that when the spur dike length reaches a certain value, the direction of the flow velocity shear front between the channel and shoal will change. The longer the spur dike, the larger the transverse fluctuating velocity at the peak of flood in the channel shoal exchange area, while the transport of the transverse hydrodynamics is obvious in the process of flood. There is an optimum length of spur dike when the shear stress in the channel and the longitudinal velocity in flood and ebb reach the maximum, and the flow velocity will decrease when the spur dike length is smaller or larger than the optimum. For a certain length of spur dike, the larger the channel shoal elevation difference, the larger the peak longitudinal flow velocity in the middle of the navigation channel in flood and ebb. However, the transverse flow velocity will first decrease and then increase. The transverse transportation is obvious when the channel shoal elevation difference increases.

关键词： spur dike hydrodynamics flow velocity channel shoal exchange physical model

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长江口深水航道回淤量时间序列混沌特征分析

水利水运工程学报 2016年第2期 97-103页

作者：丁磊窦希萍高祥宇潘昀焦增祥南京水利科学研究院港口航道泥沙工程交通行业重点实验室江苏南京210029

针对长江口深水航道回淤分布情况,以回淤最严重的H^N段为中间段P2段,H段以上为P1段,N段以下为P3段,将全部航道分为3段。采用混沌理论对深水航道全段及各分段回淤量时间序列的饱和关联维数以及K2熵进行混沌特征分析。各分段的饱和关联维... 详细信息

针对长江口深水航道回淤分布情况,以回淤最严重的H^N段为中间段P2段,H段以上为P1段,N段以下为P3段,将全部航道分为3段。采用混沌理论对深水航道全段及各分段回淤量时间序列的饱和关联维数以及K2熵进行混沌特征分析。各分段的饱和关联维数变化范围为1.80~2.15,K2熵变化范围为0.08~0.12;全段的分数维与K2熵的值大于各分段,分别为2.93和0.16。各分段的饱和关联维数研究表明,长江口深水航道回淤量的时间序列具有混沌特征,全段混沌特征的复杂性高于各分段。根据2011年,2012年和2013年长江口深水航道回淤量的时间序列,利用混沌方法对深水航道未来回淤量进行预测,各分段可预报时间尺度最多为1年,全段的可预报时间尺度为半年。给出了长江口深水航道全段及各分段回淤动力系统数学表达式的一般形式,全段需要3~6个状态变量,3个以上控制变量;各分段需要2~5个状态变量,3个以上控制变量。回淤动力系统数学表达式的一般形式可为建立回淤量预报模式提供参考。

关键词：深水航道混沌特征回淤量时间序列

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在水动力条件下高效聚磷菌除磷特性研究

科学技术与工程 2013年第8期21卷 2307-2312页

作者：焦增祥王泽梁文雷镕甄河海大学力学与材料学院南京210098

通过蓝白斑筛选技术从太湖底泥中筛选出11株聚磷菌,进一步筛选出一株高效聚磷菌,命名为G19。经过生理生化分析初步鉴定G19为李斯特氏菌属。研究表明,G19能够在废水合成培养基中较好生长,在TP初始浓度为0.33mg/L,温度为25℃下,经过两天生... 详细信息

通过蓝白斑筛选技术从太湖底泥中筛选出11株聚磷菌,进一步筛选出一株高效聚磷菌,命名为G19。经过生理生化分析初步鉴定G19为李斯特氏菌属。研究表明,G19能够在废水合成培养基中较好生长,在TP初始浓度为0.33mg/L,温度为25℃下,经过两天生长,废水合成培养基中TP下降到0.08 mg/L,除磷率高达到75.8%。实验采用自制环形水槽,当水流扰动时形成主流区和回流区,研究G19在主流区和回流区对水体中磷的去除作用,实验表明在回流区存在紊动强度较大时,高效聚磷菌除磷作用明显。试验结果对污水处理及湖泊富营养化治理具有指导意义。

关键词：蓝白斑筛选高效聚磷菌环形水槽水动力条件

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淹没齿型丁坝阻力与壅水响应关系试验研究

水运工程 2021年第4期 86-90页

作者：闫杰超李社生焦增祥中铁大桥勘测设计院集团有限公司湖北武汉430050 中交四航局港湾工程设计院有限公司广东广州510290 南昌工程学院江西南昌330099

为研究淹没齿型丁坝阻力与其壅水响应关系,利用物理水槽试验与理论分析相结合的方法,建立了淹没齿型丁坝阻力系数计算方法,其阻力系数大小主要与无量纲淹没度与相对坝长相关。进而采用动量守恒的方法构建了阻力系数与壅水效应相关联的... 详细信息

为研究淹没齿型丁坝阻力与其壅水响应关系,利用物理水槽试验与理论分析相结合的方法,建立了淹没齿型丁坝阻力系数计算方法,其阻力系数大小主要与无量纲淹没度与相对坝长相关。进而采用动量守恒的方法构建了阻力系数与壅水效应相关联的淹没齿型丁坝壅水预测模型。通过实测数据对壅水预测模型进行验证,计算结果与水槽试验数据符合良好。研究成果可为其他形式丁坝或相关涉及建筑物阻力与壅水效应研究提供参考与借鉴。

关键词：淹没齿型丁坝动量守恒阻力系数壅水

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin zeng Le Wang Wenwu Zhang Gang Li Xing Cheng Peiqiang Su Yong Wan xiang Li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong Province Key Laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury

Response of bacteria in the deep-sea sediments and the Antarctic soils to carbohydrates: Effects on ectoenzyme activity and bacterial community

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Journal of Environmental Sciences 2010年第11期22卷 1779-1785页

作者： xiang zeng School of Life Sciences Xiamen University Xiamen 361005 China. Key Laboratory of Marine Biogenetic Resources Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China School of Life Sciences and Biotechnology Shanghai Jiaotong University Shanghai 200240 China

The response of bacteria to various carbohydrates in the deep-sea sediments and the Antarctic soils was investigated using cellulose, chitin, and olive oil. It was found that the carbohydrates significantly increased the corresponding specific ectoenzyme activity （β- glucosidase, β-N-acetylglucosaminidase, lipase） in the samples from deep-sea sediments. In the case of Antarctic soil samples, the cellulose or olive oil amendments had minor or no effect on β-glucosidase or lipase activity, except the chitin which stimulated β- N-acetylglucosaminidase production. The responses of the bacteria in the deep-sea sediment sample WP02-3 and the Antarctic soil sample CC-TY2 towards the chitin amendment were further analyzed. Chitin amendments were shown to stimulate the ectoenzyme activity in all the tested sediments and the soils. The bacterial response before and after the carbohydrates amendments were compared by denaturing gradient gel electrophoresis and quantitative competitive polymerase chain reaction. Significant changes were found in the structure and density of the bacterial community in the deep sea sediments as compared to the Antarctic soil sample, where the effects were relatively lower. There was no change in the bacterial population in both studied samples in response to carbohydrates amendments. These data indicate that the bacterial communities in the oligotrophic deep-sea sediments are more dynamic than that in the Antarctic soils as they respond to the nutrient sources efficiently by regulation of ectoenzyme activity and/or changing community structure.

关键词： deep-sea sediments Antarctic soils amending cellulose chitin olive oil ectoenzyme activity

On Pseudo-Holomorphic Curves from Two-Spheres into a Complex Grassmannian G(2, 5)

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Acta Mathematica Sinica,English Series 2010年第4期26卷 759-762页

作者： Xiao xiang jiao Department of Mathematics Graduate University of Chinese Academy of Sciences Beijing 100049 P. R. China

Let s ： S2 → G（2, 5） be a linearly full totally unramified pseudo-holomorphic curve with constant Gaussian curvature K in a complex Grassmann manifold G（2, 5）. It is prove that K is either 1 4 1 or 4/5 if s is non-±holomorphic. Furthermore, K = 1/3 if and only if s is totally real. We also prove that the Gaussian curvature K is either 1 or -4/3 if s is a non-degenerate holomorphic curve under some conditions.

关键词： pseudo-holomorphic curves Gaussian curvature harmonic seouence. Kaihler angle

Impact of slope farmland use change on ecosystem services value in China,2000-2020

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Journal of Mountain Science 2023年第3期20卷 821-833页

作者： zeng Jie BIAN jiao-jiao CHEN Wan-xu Department of Geography School of Geography and Information EngineeringChina University of GeosciencesWuhan430074China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Slope farmland is an important component of farmland resources in *** utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecosystem services(ESs)is critical for effective land utilization and ecosystem *** study aims to analyze slope farmland changes in China between 2000 and 2020 and quantify the impact of these changes on ESs by the use of a land use dynamic attitude study,and an ecosystem services value(ESV)*** show that the area of slope farmland in China was mainly concentrated on slopes of 2°-6°,and exhibited a downward trend between 2000 and *** were significant differences in the spatial distribution of the farmland,which was mainly located in the Taihang,Qinling,Wushan,and Xuefeng *** increased by$179.235 million due to the conversion between slope farmland and forest,grassland,and construction land from ***,from 2010 to 2020,ESV decreased by$2613.919 million due to the conversion of forest and grassland to slope farmland as well as the conversion of slope farmland to construction land.

关键词： Slope farmland change Revised benefit transfermethod Ecosystemservicesvalue Ecosystem services management Slope farmland utilization China

Physical properties of WSTi3515S burn-resistant titanium alloy

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Rare Metals 2016年第5期35卷 361-366页

作者： Yun-Jin Lai Ping-xiang Zhang Xue-Min Zhang xiang-Hong Liu Yong Feng Hong-Chao Kou Fan-jiao Ma Wei-Dong zeng State Key Laboratory of Solidification Processing Northwestern Polytechnical University Western Superconducting Technologies Co. Ltd. School of Materials Science and Engineering Chang’an University

Development of burn-resistant titanium alloys is the most direct way of mitigating the ignition and propagation of titanium fires in jet engines. WSTi3515S alloy（Ti–35V–15Cr–0.3Si–0.1C） is a new high alloying beta type burn-resistant titanium alloy, belonging to Ti–V–Cr type alloys which have been made significant progress in engineering technology in the past 5 years. The physical properties of WSTi3515S burn-resistant titanium alloy such as the elastic properties and thermal properties were measured and analyzed in different conditions. The results show that both the Young＇s modulus and shear modulus of WSTi3515S alloy decrease slightly with the temperature increasing at the tested temperature range. The Poisson＇s ratio of WSTi3515S alloy is around 0.36. However, the thermal properties such as the specific heat, thermal diffusivity, thermal conductivity and thermal expansion increase with the temperature increasing, which results from the strengthening of lattice heat vibration at elevated temperature. And the room temperature density of WSTi3515S alloy is 5.295 gácm^（-3）.

关键词： Physical properties WSTi3515S alloy Extrusion Burn-resistant