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Methane in the Yellow Sea and East China Sea: dynamics, distribution, and production

Journal of Oceanology and Limnology 2022年第2期40卷 530-550页

作者： Wangwang YE Guanxiang DU honghai zhang Guiling zhang Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Key Laboratory of Global Change and Marine-Atmospheric Chemistry Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

The Yellow Sea(YS)and East China Sea(ECS)are important marginal seas of the western *** the dynamics of methane(CH_(4))in the YS and ECS are essential to evaluate the role of coastal seas in global *** measured dissolved CH_(4) at various depths in the water column of the YS and ECS during a cruise from March to April *** concentrations of CH_(4) varied greatly in different water masses,suggesting that the hydrographic conditions can substantially aff ect the CH_(4) *** CH_(4) budget in the shelf of the ECS,which was estimated with a box model,suggests CH_(4) consumption in the water column was the major sink(>95%),followed by a loss with a total of 2.2%CH_(4) released to the *** a local CH_(4) production of 0.28 nmol/(L·d)was needed to maintain the CH_(4) *** from laboratory incubations showed an increase in CH_(4)(1.5 times higher than the value of the control)after the addition of dimethylsulfoniopropionate(DMSP).Field incubations result in a CH_(4) production rate of 1.2 nmol/(L·d)under a N-stressed conditions(N꞉P<1),indicates that the DMSP-dependent CH_(4) production prefer to occur in the oligotrophic seawaters,where nitrogen is *** study demonstrates that the marginal seas of China is a hotspot for CH_(4) dynamics,and the cycling of methylated sulfur compounds(such as DMSP)may contribute importantly to locally formed CH_(4).This may have further implication to carbon and sulfur biogeochemical cycles in the western Pacific.

关键词： methane East China Sea Yellow Sea aerobic production dimethylsulfi de(DMS) dimethylsulfoniopropionate(DMSP)

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Processes Controlling the Carbonate Chemistry of Surface Seawater Along the 150°E Transect in the Northwest Pacific Ocean

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Journal of Ocean University of China 2022年第6期21卷 1529-1537页

作者： MOU Liang zhang honghai CHEN Zhaohui HU Yubin Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China

The problem of ocean acidification caused by the increase of atmospheric carbon dioxide concentration is becoming increasingly *** observation in the northwest Pacific Ocean was carried out along the 150°E transect in November *** distribution characteristics and influencing factors of the surface seawater carbonate chemistry,including dissolved inorganic carbon(DIC),total alkalinity(TA),pH,partial pressure of carbon dioxide(pCO_(2))and aragonite saturation state(Ω_(arag))were *** and TA ranged from 1915 to 2014μmol kg^(−1)and 2243 to 2291μmol kg^(−1),respectively;DIC in general decreased with decreasing latitude,but TA had no clear latitudinal ***_(2)values increased with the decrease of latitude and were all below the atmospheric pCO_(2)level,ranging from 332 to 387μ*** on the total hydrogen ion concentration scale(pH_(T))decreased with the decrease of latitude in the range of 8.044–8.110,whileΩ_(arag) increased with the decrease of latitude in the range of 2.61–3.88,suggesting that the spatial distributions of pH_(T) andΩ_(arag) were out of *** with the present,the predicted values of pH_(T) and Ω_(arag) by the end of this century would decrease remarkedly;larger declines were found in the higher pH_(T) and Ω_(arag) regions,resulting in the differences along the meridional gradient becoming smaller for bothpH_(T) and Ω_(arag).

关键词： ocean acidification carbonate system aragonite saturation state seawater pH Pacific Ocean

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NANOIMPRINT LITHOGRAPHY TECHNOLOGY WITH AUTOMATIC ALIGNMENT

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 1-5页

作者： FAN Xiqiu zhang honghai HU Xiaofeng JIA Ke LIU Sheng School of Electromechanical Engineering Zhejiang Ocean University Zhoushan 316000 China School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074. China School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Nanoimprint lithography （NIL） is recognized as one of the most promising candidates for the next generation lithography （NGL） to obtain sub-100 nm patterns because of its simplicity, high-throughput and low-cost. While substantial effort has been expending on NIL for producing smaller and smaller feature sizes, considerably less effort has been devoted to the equally important issue—alignment between template and substrate. A homemade prototype nanoimprint lithography tool with a high precision automatic alignment system based on Moiré signals is presented. Coarse and fine pitch gratings are adopted to produce Moiré signals to control macro and micro actuators and enable the substrate to move towards the desired position automatically. Linear motors with 300 mm travel range and 1 μm step resolution are used as macro actuators, and piezoelectric translators with 50 μm travel range and 1 nm step resolution are used as micro actuators. In addition, the prototype provides one translation （z displacement） and two tilting motion（α and β ） to automatically bring uniform intact contact between the template and substrate surfaces by using a flexure stage. As a result, 10 μm coarse alignment accuracy and 20 nm fine alignment accuracy can be achieved. Finally, some results of nanostructures and micro devices such as nanoscale trenches and holes, gratings and microlens array fabricated using the prototype tool are presented, and hot embossing lithography, one typical NIL technology, are depicted by taking nanoscale gratings fabrication as an example.

关键词： Nanoimprint lithography Alignment Moire signals

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RESEARCH ON A SCANNING NEAR-FIELD MICROSCOPY BASED ON A QUARTZ RESONATOR

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Chinese Journal of Mechanical Engineering 2001年第4期14卷 319-321页

作者： Wang Xuefang,zhang honghai,Zeng Lingdan (School of Mechanical Engineering, Huazhong University of Science and Technology) hysiol.gu.se

A scanning near field acoustic microscopy(SNAM) used in imaging the topography of precise surfaces is presented. As a micro force sensor, a non encapsulated 1 MHz quartz resonator is damped by hydrodynamic forces when approaching an object. Thus the oscillating characteristics of the leg of the quartz resonator change. While measuring the decrease of the amplitude of vibrating, the shape of the object can be obtained. Based on the analyses of the principle and key parameters of SNAM, a SNAM is exploited. A lateral resolution of 0.5 μm and vertical resolution of 2 nm has been achieved in the experiments.

关键词： Scanning near field microscopy Quartz resonator Resolution

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Responses of nitrogen cycling and related microorganisms to brackish wetlands formed by evapotranspiration

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Pedosphere 2024年第1期34卷 252-266页

作者： Jiaohui FANG Tianshu LU Jian LIU Shangbin HE Xiufeng YANG Huashan DOU honghai zhang School of Life Sciences Qufu Normal UniversityQufu 273100China Environment Research Institute Shandong UniversityQingdao 266237China Hulunbuir Academy of Inland Lakes in Northern Cold&Arid Areas Hulunbuir 021000China

Elevated evapotranspiration due to warmer air temperature could raise salinity and nutrient levels of some inland wetlands, potentially impacting nitrogen cycling. To characterize the impact of high evapotranspiration on soil microbial nitrogen cycling in inland wetlands, we compared freshwater and brackish marsh(or non-marsh) wetlands in terms of sediment ammonia-oxidizing rate(AOR), denitrifying rate(DR), and related microbial communities in a typical inland basin, the Hulun Lake basin, in China. Results showed that marsh ecosystems(ME) exhibited 31% higher AOR and 65% higher DR than non-marsh ecosystems(NE). For NE, freshwater non-marsh wetland exhibited 12% higher AOR than brackish non-marsh wetland. This was probably due to the inhibitory effects of high NH_4~+ and salinity levels on ammonia-oxidizing archaea in brackish non-marsh wetland. Conversely, DR in brackish non-marsh wetland was 23% higher than that in freshwater non-marsh wetland, with total organic carbon(TOC) significantly influencing this difference,suggesting that the higher DR in brackish non-marsh wetland was mainly due to its higher TOC level. For ME, due to the direct and indirect interference of salinity, brackish marsh wetland displayed 26% lower AOR and 19% lower DR than freshwater marsh wetland. Besides, brackish wetlands harbored distinct ammonia-oxidizing and denitrifying microbial communities compared to freshwater wetlands. The assembly of these communities was dominated by stochastic processes, while brackish wetlands exhibited more prominent deterministic processes than freshwater wetlands. Overall, high evapotranspiration altered activities and community characteristics of ammonia oxidizers and denitrifiers in inland brackish wetlands by enhancing salinity and nutrient levels,while emergent plants occurring in ME could mitigate the adverse effects of salt stress of inland brackish wetlands on nitrogen cycling.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria aquatic plants denitrifying bacteria nitrogen transformation inland wetlands

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Seasonal and spatial variations of dimethylsulfoxide(DMSO) in the East China Sea and the Yellow Sea

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Acta Oceanologica Sinica 2020年第2期39卷 1-11页

作者： Limin Zhou Min Wang honghai zhang Guipeng Yang Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education/Institute for Advanced Ocean Study Ocean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Institute of Marine Chemistry Ocean University of ChinaQingdao 266100China

Seasonal and spatial distributions of dissolved and particulate dimethylsulfoxide(DMSOd,DMSOp)were measured in the East China Sea and the Yellow Sea during March–April 2011 and October–November *** concentrations of DMSOd and DMSOp in the surface water were 20.6(5.13–73.8)and 8.90(3.75–29.6)nmol/L in spring,and 13.4(4.17–42.7)and 8.18(3.44–22.6)nmol/L in autumn,*** DMSOd and DMSOp concentrations revealed similar seasonal changes with higher values occurring in spring,mainly because of the higher phytoplankton biomass observed in ***,the ratios of DMSOp/chlorophyll a also exhibited an apparent seasonal change with higher values in autumn(35.7 mmol/g)and lower values in spring(23.4 mmol/g),thereby corresponding with the seasonal variation in the proportion of DMSO producers in the phytoplankton community between spring and *** addition,DMSOd and DMSOp concentrations in the surface seawater revealed obvious diurnal variations with the maxima appearing in the afternoon.

关键词： dimethylsulfoxide(DMSO) distribution variation East China Sea Yellow Sea

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Seasonal variations of dimethylsulfide (DMS) and dim-ethylsulfoniopropionate (DMSP) in the sea-surface microlayer and subsurface water of Jiaozhou Bay and its adjacent area

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Acta Oceanologica Sinica 2009年第2期28卷 73-86页

作者： zhang honghai YANG Guipeng LIU Chunying LI Chenxuan Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

The distributions of DMS and its precursor dimethylsulfoniopropionate, in both dissolved （DMSPd） and particulate fractions （DMSPp） were determined in the sea-surface microlayer and corresponding subsurface water of the Jiaozhou Bay, China and its adjacent area in May and August 2006. The concentrations of all these components showed a clear seasonal variation, with higher concen- trations occurring in summer. This can be mainly attributed to the higher phytoplankton biomass observed in summer. Simultaneously, the enrichment extents of DMSPd and DMSPp in the mi- crolayer also exhibited seasonal changes, with higher values in spring and lower ones in summer. Higher water temperature and stronger radiant intensity in summer can enhance their solubility and photochemical reaction in the microlayer water, reducing their enrichment factors （the ratio of concentration in the microlayer to that in the corresponding subsurface water）. A statistically significant relationship was found between the microlayer and subsurface water concentrations of DMS, DMSP and chlorophyll a, demonstrating that the biogenic materials in the microlayer come primarily from the underlying water. Moreover, our data show that the concentrations of DMSPp and DMS were significantly correlated with the levels of chlorophyll a, indicating that phytoplankton biomass might play an important role in controlling the distributions of biogenic sulfurs in the study area. The ratios of DMS/chlorophyll a and DMSPpchlorophyll a varied little from spring to summer, suggesting that there was no obvious change in the proportion of DMSP producers in the phytoplankton community. The mean sea-to-air flux of DMS from the study area was estimated to be 5.70 μmol/（m^2·d）, which highlights the effects of human impacts on DMS emission.

关键词： Dimethylsulfide (DMS) dimethylsulfoniopropionate (DMSP) sea-surface microlayer flux Jiaozhou Bay

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Vertical variations of dissolved carbohydrates in the North Yap Trench

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Journal of Oceanology and Limnology 2020年第3期38卷 606-618页

作者： GUO Chaonan SUN Chengjun YANG Guipeng zhang honghai CHEN Yan YIN Xiaofei JIANG Fenghua HUANG Yuhuan NIU Jiaohong DING Haibing Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of ChinaQingdao 266100China Key Laboratory of Marine Eco-environmental Science and Technology Marine Bioresource and Environment Research CenterFirst Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Marine Ecology and Environmental Science Laboratory Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China Qingdao Collaborative Innovation Center of Marine Science and Technology Qingdao 266100China

The concentrations of dissolved monosaccharides(MCHO),polysaccharides(PCHO),and total carbohydrates(TCHO)in the seawater samples collected from the north of the Yap Trench in the western Pacific Ocean were measured by 2,4,6-tripyridine-s-triazine(TPTZ)spectrophotometry *** results show that the concentrations of MCHO,PCHO,and TCHO ranged from 4.6 to 22.1μmol C/L,3.5 to 27.3μmol C/L,and 13.8 to 36.3μmol C/L,*** different sampling stations,the concentrations of MCHO,PCHO,and TCHO with water depth showed complex variation *** the study area,the maximum concentrations of MCHO,PCHO,and TCHO occurred in the euphotic layer and the minimum concentrations occurred in mesopelagic seawater ***,the concentrations of MCHO,PCHO,and TCHO decreased with water depth from the euphotic layer to the hadal *** average value of PCHO/TCHO was higher than the average value of MCHO/TCHO,indicating that PCHO was the main component of TCHO in north of the Yap Trench.

关键词： Yap Trench abyss hadal zone monosaccharide polysaccharide

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Forecast of Air Traffic Controller Demand Based on SVR and Parameter Optimization

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Transactions of Nanjing University of Aeronautics and Astronautics 2021年第6期38卷 959-966页

作者： zhang Yali LI Shan zhang honghai College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China

As the main body of air traffic control safety,the air traffic controller is an important part of the whole air traffic control system. According to the relevant data of civil aviation over the years,a mapping model between flight support sorties and air traffic controller demand is constructed by using the prediction algorithm of support vector regression(SVR) based on grid search and cross-validation. Then the model predicts the demand for air traffic controllers in seven regions. Additionally,according to the employment data of civil aviation universities,the future training scale of air traffic controller is predicted. The forecast results show that the average relative error of the number of controllers predicted by the algorithm is 1.73%,and the prediction accuracy is higher than traditional regression algorithms. Under the influence of the epidemic,the demand for air traffic controllers will decrease in the short term,but with the control of the epidemic,the demand of air traffic controllers will return to the pre-epidemic level and gradually increase. It is expected that the controller increment will be about 816 by 2028. The forecast results of the demand for air traffic controllers provide a theoretical basis for the introduction and training of medium and long-term air traffic controllers,and also provide method guidance and decision support for the establishment of professional reserve and dynamic control mechanism in the air traffic control system.

关键词： air traffic controller demand forecast support vector regression(SVR) grid search cross-validation

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含有螺环己烷结构的稠环斯德酮的合成

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有机化学 2012年第2期32卷 397-399页

作者：张站斌张红海北京师范大学化学学院北京100875

3-(3-芳基-3-羟基丙基)斯德酮在三氟化硼乙醚的催化作用下可以与环己酮发生类似于Oxa-Pictet-Spengler反应的成环反应,生成带有螺环己烷结构的稠环斯德酮.

关键词：斯德酮环己酮螺环化合物合成

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