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Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic systems with aggravating nutrient imbalance

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1471-x

摘要：

• Hg bioaccumulation by phytoplankton varies among aquatic ecosystems.

关键词： Plankton     Hg bioaccumulation     Physiological characteristics     A cross-system analysis     Nutrient compositions     Global data set    

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River Chief System (RCS): An experiment on cross-sectoral coordination of watershed governance

Longfei Wang, Jiaxin Tong, Yi Li

《环境科学与工程前沿（英文）》 2019年 第13卷 第4期 doi: 10.1007/s11783-019-1157-9

摘要：

The trans-regional characteristics of watershed governance produce more problems beyond the capacity of each individual water-related department, leading to the fragmentation of watershed management. The River Chief System (RCS) has experienced swift developments over the past decade in China by appointing the local government heads as river chiefs. RCS works efficiently in the short-term due to its superiority in the inclusion of clear responsibility, authority, and multi-sectoral collaboration. However, the characteristics of the authority-based vertical coordination of the hierarchical system remain unchanged, and therefore the problems of organizational logic and the responsibility dilemma still exist. Tasks including perfecting of laws, integrated watershed management, and public participation still need to be completed. RCS reflects the routine and characteristics of the migration of national governance, and as such provides new insights for other developing countries in the design of river management systems.

关键词： River Chief System     Watershed governance     Cross-sectoral coordination     Environmental protection    

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RESPONSE OF WHEAT COMPOSITE CROSS POPULATIONS TO DISEASE AND CLIMATE VARIATION OVER 13 GENERATIONS

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 400-415 doi: 10.15302/J-FASE-2021394

摘要：

Since the F5 (2005), three winter wheat composite cross populations (CCPs) based on germplasm specifically suitable for low-input conditions were subjected to natural selection under organic and conventional management. In the F6, each CCP was divided into two parallel populations (12 CCPs in total) and maintained continuously until 2018. Commonly used modern cultivars with different disease susceptibilities were grown alongside to assess the agronomic performance of the CCPs. The organically managed CCPs were comparable in yield and foliar disease resistance to two continuously used reference cultivars, Achat and Capo. In contrast, under conventional management the cv. Capo outyielded the CCPs (Achat was not tested), highlighting the importance of parental cultivar choice for specific management systems. The CCPs were found to be moderately resistant to brown rust and even to the newly emerged stripe rust races prevalent in Europe since 2011. Differences between the CCPs were mainly due to parental genetic background and were significant in the first five generations, but were no longer so in the last five generations. In addition, these differences tended to vary depending on the experimental year and the environmental stresses present. In conclusion, the CCPs despite being derived from older cultivars are able to compete with more recently released reference cultivars under organic farming practices and represent a dynamic germplasm resource.

 

关键词： evolutionary breeding     heterogeneous crop population     management system    

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Mechanics analysis of thin-walled box continuous girder with variable cross-sections in considering effect

Yuji CHEN, Qizhi LUO,

《结构与土木工程前沿（英文）》 2009年 第3卷 第4期   页码 352-356 doi: 10.1007/s11709-009-0057-7

摘要： In order to study the mechanics behavior of a thin-walled box continuous girder with variable cross-sections, using potential variation theories, considering the effect of shear lag of flange’s stress and the nonlinear geometry of vertical displacement, and evolving five generalized displacements with the spline function, the large deflection problem of the thin-walled box continuous girder with variable cross-section was transformed to a nonlinear algebraic equation, which was solved using the Newton-Raphon iterative method. The results of the calculation show that different shear lag warp functions to the cantilever, top and bottom plate should be taken to analyze the mechanics behavior of the thin-walled box continuous girder reliably. The thin-walled box continuous girder with variable cross-sections has more reasonable stress state and is more adaptable for the longitudinal change of internal forces than that with equal cross-sections. The effect of large deflection on the stress and displacement of the thin-walled box continuous girder with variable cross-sections depends on the values of the load.

关键词： thin-walled box girder with variable cross-sections     potential variational theory     shear lag     large deflection problem    

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Numerical analysis of aerodynamic noise radiated from cross flow fan

CHEN Anbang, LI Song, HUANG Dongtao

《能源前沿（英文）》 2008年 第2卷 第4期   页码 443-447 doi: 10.1007/s11708-008-0063-9

摘要： The flow field in a cross flow fan was simulated by solving the 2-D unsteady Reynolds-averaged Navier-Stokes equations. The calculated pressure fluctuations of the blades, the vortex wall, and the rear wall were then used as noise sources to calculate the sound field. The Ffowcs Williams-Hawkings (FW-H) equation was employed to predict the noise field caused by these sources. The predictions show that the rear wall and the vortex wall sources contribute significantly to the total noise and that both the predicted aerodynamic performance and noise agree well with the experimental results.

关键词： predicted aerodynamic     Williams-Hawkings     calculated pressure     aerodynamic performance     unsteady Reynolds-averaged    

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Cross-sectional network analysis of plasma proteins/metabolites correlated with pathogenesis and therapeutic

《医学前沿（英文）》 doi: 10.1007/s11684-023-1022-x

摘要： The treatment of PML/RARA+ acute promyelocytic leukemia (APL) with all-trans-retinoic acid and arsenic trioxide (ATRA/ATO) has been recognized as a model for translational medicine research. Though an altered microenvironment is a general cancer hallmark, how APL blasts shape their plasma composition is poorly understood. Here, we reported a cross-sectional correlation network to interpret multilayered datasets on clinical parameters, proteomes, and metabolomes of paired plasma samples from patients with APL before or after ATRA/ATO induction therapy. Our study revealed the two prominent features of the APL plasma, suggesting a possible involvement of APL blasts in modulating plasma composition. One was characterized by altered secretory protein and metabolite profiles correlating with heightened proliferation and energy consumption in APL blasts, and the other featured APL plasma-enriched proteins or enzymes catalyzing plasma-altered metabolites that were potential trans-regulatory targets of PML/RARA. Furthermore, results indicated heightened interferon-gamma signaling characterizing a tumor-suppressing function of the immune system at the first hematological complete remission stage, which likely resulted from therapy-induced cell death or senescence and ensuing supraphysiological levels of intracellular proteins. Overall, our work sheds new light on the pathophysiology and treatment of APL and provides an information-rich reference data cohort for the exploratory and translational study of leukemia microenvironment.

关键词： acute promyelocytic leukemia     plasma proteomics     plasma metabolomics     cross-sectional correlation network     pathogenesis     treatment    

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Air bearing center cross gap of neutron stress spectrometer sample table support system

Yang LI,Yunxin WU,Hai GONG,Xiaolei FENG

《机械工程前沿（英文）》 2016年 第11卷 第4期   页码 403-411 doi: 10.1007/s11465-016-0405-y

摘要：

A support system is the main load-bearing component of sample table for neutron stress spectrometer, and air bearing is an important element of a support system. The neutron stress spectrometer sample table was introduced, and the scheme for air bearing combination was selected. To study the performance of air bearing center cross gap, finite element models (FEMs) were established based on air motion and Reynolds equations, effects of air supply pressure, and gap parameters on the overturning moment and bearing capacity of air bearing center cross gap were analyzed. Results indicate that the width, depth, and height differences of the marble floor gap played important roles in the performance of the air bearing. When gap width is lesser than 1 mm and gap depth is lower than 0.4 mm, bearing capacity and overturning moment would vary rapidly with the variation of the width and depth. A gap height difference results in the bearing capacity dropping rapidly. The FEM results agree well with experimental results. Further, findings of the study could guide the design of the support system and marble floor.

关键词： neutron stress spectrometer     sample table     support system     air bearing     center cross gap     simulation     experiment    

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Probabilistic analysis of secant piles with random geometric imperfections

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 682-695 doi: 10.1007/s11709-021-0703-2

摘要： The failure to achieve minimum design overlap between secant piles compromises the ability of a structure to perform as designed, resulting in water leakage or even ground collapse. To establish a more realistic simulation and provide guidelines for designing a safe and cost-effective secant-pile wall, a three-dimensional model of a secant pile, considering the geometric imperfections of the diameter and direction of the borehole, is introduced. An ultrasonic cross-hole test was performed during the construction of secant piles in a launching shaft in Beijing, China. Based on the test results, the statistical characteristics of the pile diameters and orientation parameters were obtained. By taking the pile diameter D, inclination angle β, and azimuth angle α as random variables, Monte Carlo simulations were performed to discuss the influence of different design parameters on the probability density functions of the overlap of secant piles. The obtained results show that the randomness of the inclination angle and pile diameter can be well described by a normal distribution, whereas the azimuth angle is more consistent with a uniform distribution. The integrity of the secant-pile wall can be overestimated without considering the uncertainty of geometric imperfections. The failure of the secant-pile wall increases substantially with increasing spatial variability in drilling inclination and diameter. A design flowchart for pile spacing under the target safety level is proposed to help engineers design a safe and economical pile wall.

关键词： secant piles     ultrasonic cross-hole testing     probabilistic analysis     reliability-based design     random imperfections    

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跨媒体分析与推理：研究进展与发展方向 Review

Yu-xin PENG,Wen-wu ZHU,Yao ZHAO,Chang-sheng XU,Qing-ming HUANG,Han-qing LU,Qing-hua ZHENG,Tie-jun HUANG,Wen GAO

《信息与电子工程前沿（英文）》 2017年 第18卷 第1期   页码 44-57 doi: 10.1631/FITEE.1601787

摘要： 跨媒体分析与推理是计算机科学的热点问题，也是人工智能中一个具有广阔前景的研究方向。目前，尚未有文献对跨媒体分析与推理的现有方法进行归纳总结并给出它的研究进展、挑战及发展方向。为解决这些问题，本文从七个方面进行综述：（1）跨媒体统一表征理论与模型；（2）跨媒体关联理解与深度挖掘；（3）跨媒体知识图谱构建与学习方法；（4）跨媒体知识演化与推理；（5）跨媒体描述与生成；（6）跨媒体智能引擎；（7）跨媒体智能应用。本文的目标是给出跨媒体分析与推理的方法、进展以及发展方向，吸引更多人关注该领域的最新进展，通过探讨面临的挑战和研究方向，为研究者提供重要参考。

关键词： 跨媒体分析；跨媒体推理；跨媒体应用    

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Development of MCBurn and its application in the analysis of SCWR physical characteristics

Ganglin YU , Kan WANG ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 348-352 doi: 10.1007/s11708-009-0031-z

摘要： The MCBurn, a coupled code system linking the Monte Carlo N-particle transport code(MCNP) and Oak Ridge isotope generation and depletion code (ORIGEN), can resolve the basic calculation problems in reactor physical design and analysis, such as criticality, power distribution, nuclide burn up, and neutron fluence. It has been verified in the pressurized water reactor (PWR) pin model, fast reactor (FR) burn up model, and boiling water reactor(BWR) assemble model with benchmarked results. In supercritical water reactor (SCWR) physical calculations, the calculation conditions such as the geometry, the neutron spectrum, and the fuel materials, etc., are more complex than those in traditional reactors, which is a great challenge to reactor physics calculation code. However, the MCBurn code is a possible solution. In this paper, several update functions of the MCBurn in new neutron cross-section lib, code interface, and neutron flux distribution were described. The application of the MCBurn in SCWR were verified on a supercritical water reactor assemble. The calculation results show that the MCBurn is accurate and adaptable in the SCWR calculation.

关键词： Monte Carlo method     MCBurn     SCWR     neutron cross-section lib    

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Probability strength design of steam turbine blade and sensitivity analysis with respect to random parameters

DUAN Wei

《能源前沿（英文）》 2008年 第2卷 第1期   页码 107-115 doi: 10.1007/s11708-008-0018-1

摘要： Many stochastic parameters have an effect on the reliability of a steam turbine blade during practical operation. To improve the reliability of blade design, it is necessary to take these stochastic parameters into account. An equal cross-section blade is investigated and a finite element model is built parametrically. Geometrical parameters, material parameters and load parameters of the blade are considered as input random variables while the maximum deflection and maximum equivalent stress are output random variables. Analysis file of the blade is compiled by deterministic finite element method and applied to be loop file to create sample points. A quadratic polynomial with cross terms is chosen to regress these samples by step-forward regression method and employed as a surrogate of numerical solver to drastically reduce the number of solvers call. Then, Monte Carlo method is used to obtain the statistical characteristics and cumulative distribution function of the maximum deflection and maximum equivalent stress of the blade. Probability sensitivity analysis, which combines the slope of the gradient and the width of the scatter range of the random input variables, is applied to evaluate how much the output parameters are influenced by the random input parameters. The scatter plots of structural responses with respect to the random input variables are illustrated to analyze how to change the input random variables to improve the reliability of the blade. The results show that combination of the finite element method, the response surface method and Monte Carlo method is an ideal way for the reliability analysis and probability strength design of the blade.

关键词： Probability sensitivity     sensitivity analysis     number     cross-section     statistical    

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渤海海峡跨海工程自然条件分析

谭忠盛,吴永胜,万飞

《中国工程科学》 2013年 第15卷 第12期   页码 32-38

摘要：

在收集渤海海峡的气象水文、地形地貌、地层岩性、地质构造及地震活动等资料，以及现场调研的基础上，分析了渤海海峡跨海工程的建设条件。由于海峡雾大、风大，年平均大风日达67.8 d，故采用桥梁方案不利于全天候通行。由于海峡岛屿众多，且南北向成一字形分布，跨海工程线位可选择连岛方案以减小建设难度和成本。海峡第四系地层稳定性差，且第三系地层主要为玄武岩，大孔隙结构，分布极不均匀，最厚达70 m，这两套地层对隧道埋深的选择有较大影响。对于蓬莱—旅顺线位，场址附近没有活动断层，地层相对稳定。这些资料可为渤海海峡跨海通道方案的初步研究提供参考。

关键词： 渤海海峡     跨海工程     气象条件     地质条件    

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Chinese adolescents born after terminating the Bacillus Calmette--Guérin booster vaccination: subgroup analysisof a population-based cross-sectional study

null

《医学前沿（英文）》 2017年 第11卷 第4期   页码 528-535 doi: 10.1007/s11684-017-0573-0

摘要：

The prevalence of tuberculosis infection among adolescents born after terminating the Bacillus Calmette–Guérin (BCG) booster vaccination in China was estimated using tuberculin skin testing (TST) and QuantiFERON-TB Gold assay (QFT) to investigate the influence of neonatal BCG vaccination on the performance of TST. Data analysis was conducted for 2831 eligible participants aged 5–15 years from the baseline survey of a population-based multi-center prospective study. The prevalence rates of TST (induration≥10 mm) and QFT positivity were 9.3% (264/2827) and 2.5% (71/2831), respectively. The rate of QFT indeterminate result was 2.2% (62/2831). The overall agreement between TST and QFT was low (concordance= 88.0%; κ coefficient= 0.125). Only TST was positively associated with BCG vaccination with an adjusted odds ratio of 1.71 [95% confidence interval, 1.26–2.31]. A history of close contact with patients of active TB was significantly associated with positivity for TST and QFT. Our results suggested that BCG neonatal vaccination still affects TST performance, and a two-step approach might be considered for TB infection testing among adolescents in China.

关键词： tuberculin skin test     interferon-γ release assays     adolescent     agreement    

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交叉模态对结构随机振动疲劳损伤的贡献

朱学旺,刘青林

《中国工程科学》 2008年 第10卷 第10期   页码 36-41

摘要：

以小阻尼简支梁为例，讨论了交叉模态对随机振动疲劳损伤累积的贡献；结构的响应分析采用模态叠加方法，随机振动疲劳损伤累积分析采用Miner线性疲劳损伤准则。数值模拟结果表明,即使是小阻尼稀疏模态结构，交叉模态对结构振动疲劳损伤累积的贡献也是不容忽视的。

关键词： 交叉模态     结构随机振动     疲劳损伤累积     随机振动响应     模态叠加     小阻尼稀疏模态系统    

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An Integrated Analysis on the Synergistic Reduction of Carbon and Pollution Emissions from China’s Iron

Quanyin Tan,Fei Liu,Jinhui Li,

《工程（英文）》 doi: 10.1016/j.eng.2023.09.018

摘要： Decarbonization and decontamination of the iron and steel industry (ISI), which contributes up to 15% to anthropogenic CO2 emissions (or carbon emissions) and significant proportions of air and water pollutant emissions in China, are challenged by the huge demand for steel. Carbon and pollutants often share common emission sources, indicating that emission reduction could be achieved synergistically. Here, we explored the inherent potential of measures to adjust feedstock composition and technological structure and to control the size of the ISI to achieve carbon emission reduction (CER) and pollution emission reduction (PER). We investigated five typical pollutants in this study, namely, petroleum hydrocarbon pollutants and chemical oxygen demand in wastewater, particulate matter, SO2, and NOx in off gases, and examined synergies between CER and PER by employing cross elasticity for the period between 2022 and 2035. The results suggest that a reduction of 8.7%–11.7% in carbon emissions and 20%–31% in pollution emissions (except for particulate matter emissions) could be achieved by 2025 under a high steel scrap ratio (SSR) scenario. Here, the SSR and electric arc furnace (EAF) ratio serve critical roles in enhancing synergies between CER and PER (which vary with the type of pollutant). However, subject to a limited volume of steel scrap, a focused increase in the EAF ratio with neglection of the available supply of steel scrap to EAF facilities would lead to an increase carbon and pollution emissions. Although CER can be achieved through SSR and EAF ratio optimization, only when the crude steel production growth rate remains below 2.2% can these optimization measures maintain the emissions in 2030 at a similar level to that in 2021. Therefore, the synergistic effects between PER and CER should be considered when formulating a development route for the ISI in the future.

关键词： Iron and steel industry     Carbon and pollution emissions     Synergistic reduction     Technological structure     Steel scrap     Cross-elasticity    

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标题 作者 时间 类型 操作

Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic systems with aggravating nutrient imbalance

期刊论文

River Chief System (RCS): An experiment on cross-sectoral coordination of watershed governance

Longfei Wang, Jiaxin Tong, Yi Li

期刊论文

RESPONSE OF WHEAT COMPOSITE CROSS POPULATIONS TO DISEASE AND CLIMATE VARIATION OVER 13 GENERATIONS

期刊论文

Mechanics analysis of thin-walled box continuous girder with variable cross-sections in considering effect

Yuji CHEN, Qizhi LUO,

期刊论文

Numerical analysis of aerodynamic noise radiated from cross flow fan

CHEN Anbang, LI Song, HUANG Dongtao

期刊论文

Cross-sectional network analysis of plasma proteins/metabolites correlated with pathogenesis and therapeutic

期刊论文

Air bearing center cross gap of neutron stress spectrometer sample table support system

Yang LI,Yunxin WU,Hai GONG,Xiaolei FENG

期刊论文

Probabilistic analysis of secant piles with random geometric imperfections

期刊论文

跨媒体分析与推理：研究进展与发展方向

Yu-xin PENG,Wen-wu ZHU,Yao ZHAO,Chang-sheng XU,Qing-ming HUANG,Han-qing LU,Qing-hua ZHENG,Tie-jun HUANG,Wen GAO

期刊论文

Development of MCBurn and its application in the analysis of SCWR physical characteristics

Ganglin YU , Kan WANG ,

期刊论文

Probability strength design of steam turbine blade and sensitivity analysis with respect to random parameters

DUAN Wei

期刊论文

渤海海峡跨海工程自然条件分析

谭忠盛,吴永胜,万飞

期刊论文

Chinese adolescents born after terminating the Bacillus Calmette--Guérin booster vaccination: subgroup analysisof a population-based cross-sectional study

null

期刊论文

交叉模态对结构随机振动疲劳损伤的贡献

朱学旺,刘青林

期刊论文

An Integrated Analysis on the Synergistic Reduction of Carbon and Pollution Emissions from China’s Iron

Quanyin Tan,Fei Liu,Jinhui Li,

期刊论文