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Journal of Environmental Sciences 2011年第9期23卷 1452-1459页

作者： Tianran chen Kefu yu Shu li Tegu chen Qi Shi Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Barium to calcium （Ba/Ca） ratio in corals has been considered as a useful geochemical proxy for upwelling,river flood and other oceanic ***,recent studies indicated that additional environmental or biological factors can influence the incorporation of Ba into coral *** this study,Ba/Ca ratios of two Porites corals collected from Daya Bay,northern South China Sea were ***/Ca signals in the two corals were ‘anomalous’ in comparison with Ba behaviors seen in other near-shore corals influenced by upwelling or riverine *** Ba/Ca profiles displayed similar and remarkable patterns characterized by low and randomly fluctuating background signals periodically interrupted by sharp and large synchronous peaks,clearly indicating an environmental *** analysis indicated that the Ba/Ca profiles were not correlated with previously claimed environmental factors such as precipitation,coastal upwelling,anthropogenic activities or phytoplankton blooms in other *** maxima of Ba/Ca appeared to occur in the period of Sr/Ca maxima,coinciding with the winter minimum temperatures,which suggests that the anomalous high Ba/Ca signals were related to winter-time low sea surface *** speculated that the Ba/Ca peaks in corals of the Daya Bay were most likely the results of enrichment of Ba-rich particles in their skeletons when coral polyps retracted under the stresses of anomalous winter low *** this case,Ba/Ca ratio in relatively high-latitude corals can be a potential proxy for tracing the low temperature stress.

关键词： Ba/Ca barium Porites coral cold water stress northern South China Sea

Theory and practice of the optimizing of charging structure in EAF steelmaking

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Journal of University of Science and Technology Beijing 2005年第4期12卷 313-316页

作者： yu chen Shiqi li Shujuan Ji Runzao liu Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China

The viewpoint about harmful residual element control, the charging structure and its influence on production index due to the diversification of raw material in EAF steelmaking was expatiated. The residual element control model, the concept of the proportion of iron and steel and the charging structure triangle were putted forward. Based on theoretical calculation and statistical analysis, the influence of charging structure on production index was discussed, and it was found that the utilizing efficiency of energy will reduce as the proportion of iron and steel in EAF steelmaking increases.

关键词： charging structure element control EAF steelmaking

Theoretical and experimental investigation of holographic reconstruction and prediction of multi-source hybrid acoustic field

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 282-299页

作者： BI Chuanxing chen Jian chen Xinzhao yu Fei li Weibing Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China Dynamic Measuring Center Hefei University of Technology Hefei 230009 China

Study on a multi-source hybrid acoustic field is very important for nearfield acoustic holography (NAH) to be applied in the practical engineering field. In this paper, two methods based on the distributed source boundary point method (DSBPM) for holographic reconstruction and prediction of multi-source hybrid acoustic field, namely combination method with single surface measurement and combination method with multi-surface measurement, are proposed. Then, an experiment on two coherent speakers is carried out. By comparison of the reconstructed and predicted results and the actual measured results, the validity of the two methods and the superiority of the combination method with multi-surface measurement are proved. Considering the high sensitivity of the reconstructed results to measurement errors, the Tikhonov regularization method is proposed to stabilize the reconstruction procedure and restrict the influence of errors. And then, the optimal reconstructed results can be obtained and the reliability of holographic reconstruction and prediction is assured.

关键词： acoustic holography, boundary point, distributed source, acoustic radiation, regularization.

Effect of Azoxystrobin on Oxygen Consumption and cyt b Gene Expression of Colletotrichum capsici from Chilli Fruits

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Agricultural Sciences in China 2009年第5期8卷 628-631页

作者： chen yu JIN li-hua ZHOU Ming-guo College of Plant Protection Nanjing Agricultural University~Key Laboratory of Monitoring and Management of Crop Diseases and PestInsects Ministry of Agriculture Nanjing 210095 P.R. China

Azoxystrobin acts as an inhibitor of electron transport by binding to the Qo center of cytochrome b （cyt b）. Resistance to azoxystrobin was usually caused by the point mutation of cyt b gene or by the induction of alternative respiration. Oxygen consumption test for mycelia of Colletotrichum capsici showed that azoxystrobin inhibited mycelial respiration within 12 h; however, as time went on, the respiration of the mycelia recovered when the mycelia were treated with azoxystrobin and salicylhydroxamic acid （SHAM, a known inhibitor of alternative respiration）, and the oxygen consumption of the mycelia could not be inhibited. Meanwhile, cytochrome b （cyt b） gene expression increased with the recovery of mycelial respiration. The increased cyt b gene expression might play a role in the development of resistance to azoxystrobin in C. capsici.

关键词： QoI fungicides gene expression chili fungal respiration azoxystrobin resistance

Numerical simulation on fluid flow behavior during 3-dimensional dendrite growth with random preference angle

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China Foundry 2022年第5期19卷 387-394页

作者： Qi Wang Ke-jie Feng Shi-jie Zhang chen-yu li Ri li School of Materials Science and Engineering Hebei University of TechnologyTianjin 300401China

The flow behavior of three-dimensional(3D)dendrite growth with random preferred angle under natural convection was studied by using the Lattice Boltzmann-Cellular Automata(LB-CA)method with dynamic and static *** this model,the temperature field,flow field and solute field calculated by Lattice Boltzmann method(LBM)and dendrite growth calculated by CA method were carried out in static and dynamic grids respectively,and the coupling between LBM and CA was performed by interpolation of calculation parameters between dynamic and static *** show that the asymmetry of solid phase distribution makes the streamline distribution more *** the initial stage of multiple dendrites growth,the fluid flow is relatively *** dendrites grow close to each other,the fluid flow is blocked and can only flow along the gap between *** the wall equiaxed-columnar-central equiaxed crystals transformation(ECET)process,dense eddy current is formed at the wall equiaxed crystals at ***,when the wall equiaxed crystals gradually develop into columnar crystals,the eddy current moves with the solid-liquid *** the central equiaxed crystals are formed,the eddy current at the front of the columnar crystals gradually *** eddies appear as the central equiaxed crystal grows.

关键词： two sets of grids randomly select preference angle three dimensional LB-CA model fluid flow

Brainstem abscesses caused by listeria monocytogenes:A case report

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World Journal of Clinical Cases 2022年第22期10卷 7924-7930页

作者： Jie Wang yu-chen li Ke-yu Yang Jing Wang Zan Dong Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuan 030000Shanxi ProvinceChina Department of Critical Care Medicine Aerospace Center HospitalBeijing 100049China Department of Neurology Yuncheng Central HospitalYuncheng 043100Shanxi ProvinceChina

BACKGROUNDIntracranial listeria infections are common in newborns and immunocompromisedindividuals, but brainstem abscesses are *** SUMMARYWe report a rare case of brainstem abscesses caused by listeria monocytogenes in apreviously healthy adult patient. The patient’s magnetic resonance imagingexamination showed multiple brain abscesses, and his second cerebrospinal fluidculture test indicated the presence of listeria monocytogenes. Despite earlyempirical therapy, the patient’s condition progressively deteriorated. Because thepatient's abscesses were located in the brainstem and multiple lobes, surgery wasnot possible. The patient died 40 d after *** case highlights the importance of rational clinical use of drugs to avoidpotentially serious infectious complications.

关键词： listeria monocytogenes Brainstem abscesses Drug Brain MRI Therapy Prognosis Case report

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Journal of Computer Science & Technology 2022年第1期37卷 231-251页

作者： Jian-Zhe Zhao Xing-Wei Wang Ke-Ming Mao chen-Xi Huang yu-Kai Su yu-chen li Software College Northeastern UniversityShenyang 110169China State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China College of Computer Science and Engineering Northeastern UniversityShenyang 110819China

Differential privacy(DP)is widely employed for the private data release in the single-party *** utility could be degraded with noise generated by ubiquitous data correlation,and it is often addressed by sensitivity reduction with correlation ***,increasing multiparty data release applications present new challenges for existing *** this paper,we propose a novel correlated differential privacy of the multiparty data release(MP-CRDP).It effectively reduces the merged dataset's dimensionality and correlated sensitivity in two steps to optimize the *** also propose a multiparty correlation analysis *** on the prior knowledge of multiparty data,a more reasonable and rigorous standard is designed to measure the correlated degree,reducing correlated sensitivity,and thus improve the data ***,by adding noise to the weights of machine learning algorithms and query noise to the release data,MP-CRDP provides the release technology for both low-noise private data and private machine learning *** experiments demonstrate the effectiveness and practicability of the proposed method on the utilized Adult and Breast Cancer datasets.

关键词： correlated differential privacy multiparty data release machine learning

Synthesis, Crystal Structure and Biological Activities of 2-(4-Fluorophenyl)-2-oxo-1-(1H-1,2,4-triazol-1-yl) ethyl morpholine-4-carbodithioate

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Chemical Research in Chinese Universities 2005年第6期21卷 673-676页

作者： XU liang-zhong ZHU Chong-yi yu chen-long li Kai SI Guo-dong College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 P. R. China

The title compound, 2-（ 4-fluorophenyl ） -2-oxo-1-（ 1H-1, 2,4-triazol-1-yl ） ethyl morpholine-4-carbodithioate, was synthesized and its structure was confirmed by means of IR, MS, 1 H NMR and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The preliminary biological test showed that the synthesized compound possesses some biological activities.

关键词： 1H-1,2,4-Triazole Morpholine Crystal structure Biological activity

Effect of Micro-Area pH Value on Formation of Different Rust Phases of Weathering Steel in Initial Corrosion Period

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Journal of Iron and Steel Research International 2010年第9期17卷 69-72,78页

作者： chen Xiao-ping WANG Xiang-dong liU Qing-you MI Feng-yi chen Ying li yu-su Central Iron and Steel Research Institute Beijing 100081 China

The formation of protective rust layer of atmospheric corrosion resistance was discussed for weathering steel. The rust layers of experimental steels were made by using an accelerating industrial atmospheric corrosion test of dry-wet cyclic immersion. Furthermore XRD were used to measure and analyze the rust layers. The initial corrosion processes below thin water film were observed and the changes of micro-area pH value were measured. The results are as follows： The corrosion processes of P-RE weathering steel are obviously different from those of carbon steel. The surface of P-RE weathering steel rapidly forms a-FeOOH and the micro-area pH value is above 5.4 during the initial corrosion period. While the component of the rust layer for the carbon steel is mainly Fe3O4 and the microarea pH value is below 3.8.

关键词： weathering steel pH value micro area rust phase

供水管路中驼峰气阻的临界平衡实验研究(英文)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第3期18卷 167-178页

作者： Wu-yi WAN chen-yu li yun-qi yu Department of Hydraulic Engineering College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 310072 China

目的:输水管道的驼峰气阻是指由于管路高峰位置的滞气作用使气体不断聚积在峰顶附近、产生的气体阻碍水流的局部水力现象。它能够导致管路过水断面减小、输水能耗增加、输送效率降低和管路压力振荡等后果,严重威胁海底管道输水的稳定性... 详细信息

目的:输水管道的驼峰气阻是指由于管路高峰位置的滞气作用使气体不断聚积在峰顶附近、产生的气体阻碍水流的局部水力现象。它能够导致管路过水断面减小、输水能耗增加、输送效率降低和管路压力振荡等后果,严重威胁海底管道输水的稳定性和安全性。本文旨在分析滞留气团在供水管道中的力学平衡、能量损失、移动和溢出机理,研究水流流速对气团的推移特性,提出预测和消除驼峰气阻的方法,使输水管道免受驼峰气阻的危害,提高输水管道的供水效率。创新点:1.设计了具有连续坡角变化的圆弧形驼峰管道实验,该实验可以定量模拟气团体积和平衡角度;2.建立了驼峰气阻的水头损失经验公式和恒定流情况下驼峰气阻的管道坡角和流速的对应关系式,可用于预测和消除驼峰气阻的危害。方法:1.通过驼峰气团的受力特性分析,获得满足量纲和谐的力学平衡方程;2.采用试验观察和测试获得有无气泡情况下的水头损失和平衡状态下的坡角,通过等价球体方法对测试数据进行无量纲拟合,获得气阻的水头损失方程系数,并通过流速和平衡坡角建立恒定流情况下的临界平衡方程;3.基于试验拟合获得临界平衡方程,建立预测和评估气阻的准则系数,并提出消除气阻的水流临界流速。结论:1.当管路流速较小时,供水管路的驼峰顶端可能滞留和聚集气体,形成驼峰气阻;气体体积越大对水流阻碍越明显,可能造成的水头损失也越大;2.利用等价球体法可以极大地简化驼峰气阻的形状,并良好地模拟气阻的平衡特性和阻力特性;3.管道流速是影响驼峰气阻临界平衡位置的最重要因素,通过减小管道起伏的坡角或增加水流流速可以防止和消除驼峰气阻的危害。

关键词：驼峰管道管流滞留气团水力试验供水管道