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Biofilm-overproducing Bacillus subtilis B12Δywcc decreases Cd uptake in Chinese cabbage through increasing Cd-immobilizing related gene abundance and root surface colonization

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journal of Environmental Sciences 2022年第10期34卷 84-93页

作者： yanyan ge Zhanbiao ge jinwei Zheng Xiafang Sheng Linyan He College of Life Sciences Nanjing Agricultural UniversityKey Laboratory of Agricultural and Environmental MicrobiologyMinistry of AgricultureNanjing 210095China

Biofilm-producing bacteria can decrease Cd uptake in vegetables, but mechanisms underlying this effect are poorly characterized. In this study, two mutant strains B12Δywcc and B12ΔSlr R were constructed from a biofilm-producing Bacillus subtilis strain B12. Then, the impacts of strain B12 and its high biofilm-producing mutant strain B12Δywcc and low biofilmproducing mutant strain B12ΔSlr R on Cd availability and uptake in Chinese cabbage and the related mechanisms were investigated in the Cd-polluted soil. Strain B12 and its mutants B12Δywcc and B12ΔSlr R increased the dry biomasses of edible tissues by 54%–130% compared with the controls. Strain B12 and its mutant B12Δywcc reduced the soil available Cd content by 36%–50% and root and edible tissue Cd contents by 23%–50% compared with the controls. Furthermore, the mutant strain B12Δywcc reduced the edible tissue Cd content by40% and increased the polysaccharide content by 23%, invertase activity by 139%, and gene copies of the cum A by 4.5-fold, eps A by 7.1-fold, and cad A by 4.3-fold, which were involved in Cd adsorption in the rhizosphere soils, respectively, compared with strain B12. The polysaccharide content and cum A, eps A, and cad A gene copy numbers showed significantly reverse correlations with the available Cd content. Notably, the mutant strain B12Δywcc showed better ability to colonize the vegetable root surface than strain B12. These findings demonstrated that the biofilm-overproducing mutant strain B12Δywcc increased the polysaccharide production and Cd-immobilizing related cum A, eps A, and cad A gene copies, resulting in lower Cd availability and accumulation in Chinese cabbage in the Cd-polluted soil.

关键词： Biofilm-producing Bacillus subtilis Mutant strain with biofilm overproduction Cd uptake in vegetable Cd-stabilizing related genes Bacterial colonization and biofilm formation

Dispersal of the Zhujiang River(Pearl River) derived sediment in the Holocene

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Acta Oceanologica Sinica 2014年第8期33卷 1-9页

作者： ge Qian LIU j.P. XUE Zuo CHU Fengyou Key Laboratory of Submarine geosciences State Oceanic AdministrationSecond Institute of OceanographyState Oceanic Administration Department of Marine Earth and Atmospheric SciencesNorth Carolina State UniversityRaleighNC 27695USA

High-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） Holocene Zhujiang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zhujiang River Delta, southwest-ward off the Guangdong coast, to the Leizhou Peninsula. Two depo-centers, one proximal and one distal, are identified. On the continental shelf off the west Guangdong Province, the mud is deposited in water depth shallower than 50 m; while to the southeast of the Zhujiang River Estuary, the mud area can extend to the -120 m isobath. A combined analysis with the stratigraphic sequences of other muddy deposits in the West-ern Pacific marginal seas （mainly Changjiang （yangtze） and Huanghe （yellow） Rivers derived） indicates that the initiation of the Zhujiang River muddy deposit can be further divided into two stages： Stage 1 is before the mid-Holocene sea-level highstand （ca. 7.0 cal. ka BP）, the proximal mud was mostly deposited after 9.0 cal. ka BP, when the sea-level rose slowly after the Meltwater Pulse -1C; Stage 2, after the mid-Holocene sea-level highstand, clinoform developed on the continental shelf off the west Guangdong Province, extending ca. 400 km from the Zhujiang River Estuary. The proximal clinoform thins offshore, from ca. 10 m thickness around 5-10 m water depth to less than 1-2 m around 20-30 m water depth. In addition, we also find a de-veloped distal clinoform in the east of the Leizhou Peninsula.

关键词： South China Sea Zhujiang River mud clinoform

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超级街区路网模式在中西方的发展与演变

城市建筑 2025年第1期22卷 78-84页

作者：葛欣韩雨晨东南大学建筑设计研究院有限公司东南大学建筑学院

超级街区是二元分化规划思想的产物,体现为边界干道和内部道路在规划、建设、管控上的强烈对比,继而呈现为形态和功能上的内外差异。在中西方,超级街区由于成因和发展历程的不同,产生了诸多形态、功效各异的范式。然而,既有研究对于超... 详细信息

超级街区是二元分化规划思想的产物,体现为边界干道和内部道路在规划、建设、管控上的强烈对比,继而呈现为形态和功能上的内外差异。在中西方,超级街区由于成因和发展历程的不同,产生了诸多形态、功效各异的范式。然而,既有研究对于超级街区普遍采取批判的态度,忽略了其在超越街区的尺度上组织城市形态与功能的价值和潜力。本研究剖析了超级街区的定义,梳理了中西方超级街区的发展演变历程,提炼出各阶段路网的典型范式及变体。

关键词：超级街区路网中西方范式变体

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气候变化背景下沿海城市轨道交通网络韧性评估——以深圳市为例

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灾害学 2025年第1期40卷 167-173,186页

作者：胡文昊尚凯葛懿夫翟国方张钰佳南京大学建筑与城市规划学院江苏南京210093 清华大学建筑学院北京100084

轨道交通网络是大型城市人口高效通勤的有力保障,在全球气候变化背景下,沿海城市轨道交通网络受到海平面上升及一系列连锁效应的威胁。该文以深圳市为例对未来不同情景下的轨道交通网络进行复杂网络建模及韧性评估。结果表明:①海平面... 详细信息

轨道交通网络是大型城市人口高效通勤的有力保障,在全球气候变化背景下,沿海城市轨道交通网络受到海平面上升及一系列连锁效应的威胁。该文以深圳市为例对未来不同情景下的轨道交通网络进行复杂网络建模及韧性评估。结果表明:①海平面的不断上升,对轨道交通网络的整体韧性带来显著影响;②当考虑到气候变化的累积效应时,网络韧性下降更加显著;③关键站点的失效对轨道交通网络的影响更大,包括自身失效的影响和造成其他站点间接失效的影响;④沿海存在多处较严重的地表沉降区域,区域内站点受到地表沉降和海平面上升的共同作用。研究以海平面上升作为灾害背景进行轨道交通网络的韧性评估并将地表沉降因素考虑在内,可为沿海城市轨道交通的长期安全发展提供理论参考。

关键词：气候变化海平面上升轨道交通网络韧性

Effect of particle size on the thermal performance of NaNO3/SiC)2/C composite phase-change materials

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Particuology 2019年第3期17卷 169-175页

作者： Liang Liu Liqiong Wang Weichun ge yanfeng ge yun Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China State Grid Liaoning Electric Power Supply Co. Ltd. Shenyang 110004 China

Storage of thermal energy is a key technology for energy conservation and application of renewable energy sources. In this paper, the thermal performance of inorganic composite phase-change materials (PCMs;NaNO3/SiO2/C) is studied under extreme thermal conditions and the effect of raw particle size is examined. We designed a thermal shock test platform with a diffusive combustion system and in-situ infrared thermal imaging. The influences of the heat flux magnitude and exposure time on the performance of the PCMs were examined under vertical thermal shock conditions. Leakage of molten salt in the composite PCMs was observed as the heat flux reached a threshold point. The morphology and thermal properties were characterized by ex-situ SEM, XRD, DSC, and BET. Raw particles with sizes in the range of 105-500 μm were used to synthesize the composite material and examine its role in thermal shock behavior. Our experiments showed that deterioration of the thermal storage density was slowed as the particle size was increased. This work provides useful guidance for improving the anti-thermal shock ability of future material designs.

关键词： Thermal storage Phase change material Particle size Thermal shock Decomposition temperature

Convergence Rate of the Asymmetric Deffuant-Weisbuch Dynamics

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journal of Systems Science & Complexity 2015年第4期28卷 773-787页

作者： ZHANG jiangbo CHEN ge The Faculty of Science Southwest Petroleum University Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences

This paper considers the convergence rate of an asymmetric Deffuant-Weisbuch *** model is composed by finite n interacting *** this model,agent i’s opinion is updated at each time,by first selecting one randomly from n agents,and then combining the selected agent j’s opinion if the distance between j’s opinion and i’s opinion is not larger than the confidence radiusε*** yields the endogenously changing inter-agent *** on the previous result that all agents opinions will converge almost surely for any initial states,the authors prove that the expected potential function of the convergence rate is upper bounded by a negative exponential function of time t when opinions reach consensus finally and is upper bounded by a negative power function of time t when opinions converge to several different limits.

关键词： Convergence rute Deffuant-Weisbuch model multi-agent systems opinion dynamics.

Statistical properties of pseudo-particle systems

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Particuology 2010年第4期8卷 332-342页

作者： Feiguo Chen Wei ge State Key Laboratory of Multi-Phase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Pseudo-particle modeling （PPM）, a molecular modeling method which combines time-driven algorithms and hard molecule modeling, was originally developed for simulating gas in complex multiphase systems （ge ＆ Li, 2003; ge et al., 2005; ge, 1998）. In this work, the properties of two- and three-dimensional pseudo-particle systems, namely, mean free path, compressibility factor, self-diffusion coefficient and shear viscosity, are systematically measured by using PPM. it is found that in terms of an effective diameter, the results well conform to the Chapman-Enskog theory, thus suggesting that PPM can be employed to simulate the micro- and meso-scale behavior of ordinary gas and fluid flows.

关键词： Pseudo-particle modeling Molecular dynamics Transport coefficient Chapman-Enskog theory

Visual tracking using discriminative representation with l2 regularization

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Frontiers of Computer Science 2019年第1期13卷 199-211页

作者： Haijun WANG Hongjuan ge College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China Aviation Information Technology Research and Development Center Binzhou UniversityBinzhou 256603China

In this paper,we propose a novel visual tracking method using a discriminative representation under a Bayesian ***,we exploit the histogram of gradient (HOG)to generate the texture features of the target templates and ***,we introduce a novel discriminative representation and l2-regularized least squares method to solve the proposed representation *** proposed model has a closed-form solution and very high computational ***,a novel likelihood function and an update scheme considering the occlusion factor are adopted to improve the tracking performance of our proposed method. Both qualitative and quantitative evaluations on 15 challenging video sequences demonstrate that our method can achieve more robust tracking results in terms of the overlap rate and center location error.

关键词： visual tracking discriminative representation Bayesian framework closed-form solution

Enhancing manual P-phase arrival detection and automatic onset time picking in a noisy microseismic data in underground mines

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International journal of Mining Science and Technology 2018年第4期28卷 683-691页

作者： Mborah Charles ge Maochen Department of Mining and Nuclear Engineering Missouri University of Science and Technology

Accurate detection and picking of the P-phase onset time in noisy microseismic data from underground mines remains a big challenge. Reliable P-phase onset time picking is necessary for accurate source location needed for planning and rescue operations in the event of failures. In this paper, a new technique based on the discrete stationary wavelet transform （DSWT）and higher order statist!cs, is proposed for processing noisy data from underground mines. The objectives of this method are to （1） Improve manual detection and tPicking of P-phase onset; and （ii） provide an automatic means of detecting and picking P-phase onset me accurately. The DSWT is first used to filter the signal over several scales. The manual P-phase onset detection and picking are then obtained by computing the signal energy across selected scales with frequency bands that capture the signal of interest. The automatic P-phase onset, on the other hand, is achieved by using skewness- and kurtosis-based criterion applied to selected scales in a time-frequency domain. The method was tested using synthetic and field data from an underground limestone mine. Results were compared with results obtained by using the short-term to long-term average （STA/LTA） ratio and that by Reference ge et al. （2009）. The results show that the me!hod provides a more reliable estimate of the P-phase onset arrival than the STA]LTA method when the signal to noise ratio is very low. Also, the results obtained from the field data matched accurately with the results from Reference ge et al. （2009）.

关键词： Manual P-phase detection Automatic onset picking Noisy microseismic data Kurtosis Skewness