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j.urnal of Environmental Sciences 2020年第4期32卷 331-342页

作者： Dantong zhu Xiangj. Cheng David j.Sample Mohammad Nayeb Yazdi State Key Laboratory of Subtropical Building Science South China University of TechnologyGuangzhou 510640China School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510640China Department of Biological System Engineering Virginia Polytechnic Institute and State UniversityVirginia Beach 23455United States

Nitrogen in pond sediments is a maj.r water quality concern and can impact the productivity of *** oxygen is an important factor for improving water quality and boosting fish growth in aquaculture ponds,and plays an important role in the conversion of ammonium-nitrogen(NH4-N)to nitrite-nitrogen(NO2--N)and eventually nitrate-nitrogen(NO3--N).A central goal of the study was to identify the best aeration method and strategy for improving water quality in aquaculture *** conducted an experiment with six tanks,each with a different aeration mode to simulate the behavior of aquaculture *** results show that a 36 hr aeration interval(Tc=36 hr:36 hr)and no aeration resulted in high concentrations of NH4-N in the water *** a 12 hr interval time(Tc=12 hr:12 hr)resulted in higher NO2--N and NO3--N concentrations than any other aeration *** from an 8 hr interval time(Tc=8 hr:8 hr)and 24 hr interval time(Tc=24 hr:24 hr)were comparable with those of continuous aeration,and had the benefit of being in use for only half of the time,consequently reducing energy consumption.

关键词： Intermittent aeration Nitrogen Water column Sediment resuspension and release Sediment Sediment pore water

Characterization of Placic Horizons in Ironstone Soils of Louisiana, USA

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Pedosphere 2010年第4期20卷 409-418页

作者： D. C. WEINDORF N. BAKR Y. zhu B. HAGGARD S. j.HNSON j. DAIGLE Louisiana State University Agricultural Center 307 MB Sturgis Hall Baton Rouge LA 70803 (USA) United States Department of Agriculture-Natural Resources Conservation Service 3737 Government Street AlexandriaLA 71302 (USA)

Placic horizons, defined as thin, wavy, hardened layers of iron and organic matter, are rare within the United States, occurring only in Washington, Alaska, and Hawaii. While ironstone is common in many soils of the southeastern United States, it is not known to contain appreciable organic matter. As a pilot study evaluating the j.stification for a larger study on ironstone in Louisiana, a 40 m lateral exposure with suspected placic horizons was evaluated in Vernon Parish, Louisiana. Results of laboratory analysis show elevated levels of iron and organic matter in the suspect horizons that meet the criteria of placic horizons as defined by the Soil Survey Staff. Based on the results of this study, additional evaluation of multiple pedons with similar features is warranted. Should additional pedons demonstrate similar properties, a new great group of 'Petrudepts' would be needed to describe both the placic horizons in the pedon and the udic moisture regime in which they occur.

关键词： ortstein pedon petroferric contact Petrudepts

A Flexible and Lightweight Biomass-Reinforced Microwave Absorber

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Nano-Micro Letters 2020年第10期12卷 1-15页

作者： Yan Cheng j.stin zhu Yeow Seow Huanqin Zhao Zhichuan j.u Guangbin j. College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China School of Materials Science and Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Singapore-HUj.Alliance for Research and Enterprise NEW-CREATE PhaseⅡCampus for Research Excellence and Technological Enterprise(CREATE)Singapore 138602Singapore

Developing a flexible,light-weight and effective electromagnetic(EM)absorber remains challenging despite being on increasing demand as more wearable devices and portable electronics are ***,we report a flexible and lightweight hybrid paper by a facile vacuumfiltration-induced self-assembly process,in which cotton-derived carbon fibers serve as flexible skeletons,compactly surrounded by other microwave-attenuating components(reduced graphene oxide and Fe3O4@C nanowires).Owing to its unique architecture and synergy of the three components,the asprepared hybrid paper exhibits flexible and lightweight features as well as superb microwave absorption *** absorption intensity with reflection loss as low as-63 dB can be achieved,and its broadest frequency absorption bandwidth of 5.8 GHz almost covers the entire Ku *** a hybrid paper is promising to cope with ever-increasing EM *** work also paves the way to develop low-cost and flexible EM wave absorber from biomass through a facile method.

关键词： Flexible Biomass Microwave absorption Dielectric loss Magnetic loss

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基于双目视觉技术的茶叶嫩芽定位方法研究

农机化研究 2025年第2期47卷 49-53页

作者：朱龙舜郑旻璐东南大学成贤学院南京210088 南京机电职业技术学院南京211306

进一步提升茶叶嫩芽定位的准确性及茶叶嫩芽采摘的作业效率,选取双目视觉技术作为切入点,针对其识别、定位、采摘等环节展开设计研究。考虑茶叶嫩芽采摘的基础特征和双目视觉技术的应用条件,合理搭建双目视觉模型,选用立体匹配的核心定... 详细信息

进一步提升茶叶嫩芽定位的准确性及茶叶嫩芽采摘的作业效率,选取双目视觉技术作为切入点,针对其识别、定位、采摘等环节展开设计研究。考虑茶叶嫩芽采摘的基础特征和双目视觉技术的应用条件,合理搭建双目视觉模型,选用立体匹配的核心定位算法,完成茶叶嫩芽的定位方法与采摘功能优化,并布置相应的试验机构,展开定位采摘验证试验。结果表明:基于双目视觉技术的茶叶嫩芽定位方法应用具有显著的优越性,较普通定位方法而言,识别误匹配率可降低至4.01%,平均漏采率为3.20%,嫩芽采摘完整率达93.40%,可以很好地促进茶叶嫩芽的后续处理加工,是采摘茶叶嫩芽的品质化的重要基础保障。

关键词：茶叶嫩芽定位双目视觉立体匹配采摘完整率品质化

Fluidized-Bed Bioreactor Applications for Biological Wastewater Treatment： A Review of Research and Developments

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Engineering 2017年第3期3卷 330-342页

作者： Michael j. Nelson George Nakhla j.sse zhu Particle Technology Research Center The University of Western Ontario London ON N6A 5B9 Canada

Wastewater treatment is a process that is vital to protecting both the environment and human health. At present, the most cost-effective way of treating wastewater is with biological treatment processes such as the activated sludge process, despite their long operating times. However, population increases have created a demand for more efficient means of wastewater treatment, Fluidization has been demonstrated to in- crease the efficiency of many processes in chemical and biochemical engineering, but it has not been widely used in large-scale wastewater treatment. At the University of Western Ontario, the circulating fluidized-bed bioreactor （CFBBR） was developed for treating wastewater. In this process, carrier particles develop a biofilm composed of bacteria and other microbes. The excellent mixing and mass transfer characteristics inherent to fluidization make this process very effective at treating both municipal and industrial wastewater. Studies of lab- and pilot-scale systems showed that the CFBBR can remove over 90% of the influent organic matter and 80% of the nitrogen, and produces less than one-third as much biological sludge as the activated sludge process. Due to its high efficiency, the CFBBR can also be used to treat wastewaters with high organic solid concentrations, which are more difficult to treat with conventional methods because they require longer residence times; the CFBBR can also be used to reduce the system size and footprint. In addition, it is much better at handling and recovering from dynamic loadings （i.e., varying influent volume and concentrations） than current systems. Overall, the CFBBR has been shown to be a very effective means of treating wastewa- ter, and to be capable of treating larger volumes of wastewater using a smaller reactor volume and a shorter residence time. In addition, its compact design holds potential for more geographically localized and isolat- ed wastewater treatment systems.

关键词： Wastewater Biological wastewater treatment Fluidized-bed technology Fluidized-bed reactor Biological nutrient removal Bio-particles High-efficiency process

Variation and mechanisms of clastic reservoir quality in the Paleogene Shahej.e Formation of the Dongying Sag, Bohai Bay Basin, China

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Petroleum Science 2014年第2期11卷 200-210页

作者： Zhang Qin zhu Xiaomin Ronald j.Steel Zhong Dakang College of Geosciences China University of Petroleum State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Department of Geological Sciences The University of Texas at Austin

Reservoir quality varies greatly in the Shahej.e Formation in the Dongying Sag. It is essential to analyze the variation and mechanisms of reservoir quality for determining the controlling factors based on cores, porosity measurements and fluid inclusion techniques and so on. The sandstones in the fluvial, （fan） delta-front have the best reservoir quality due to the depositional conditions mechanically controlling the petrology configuration and the primary porosity, and chemically influencing the diagenesis and development of secondary pores. The activity of the boundary faults and the sedimentary facies dominate the variation of reservoir quality in different areas and intervals. The reservoir quality varies with the position of sandstone beds in different vertical models of sandstone and mudstone. This mainly arose from the strong cementation or strong dissolution in the sandstone caused by the diagenesis evolution of adj.cent mudstone. With higher oil saturation reservoir quality is better because the hydrocarbon charge favors dissolution and restricts cementation. Diagenesis, depositional conditions and tectonic setting are the key controls of reservoir quality in the Shahej.e Formation of the Dongying Sag.

关键词： Reservoir quality variation clastic reservoir quality hydrocarbon charge vertical models ofsandstone and mudstone controlling factor

水力循环高架设施栽培装置优化设计及试验分析

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农机化研究 2025年第2期47卷 165-170,185页

作者：朱庆松严露露李玉斌白东方朱赞彬信阳农林学院河南信阳464000

高架设施栽培模式提升了温室作物的产量和质量。为此,针对固定式高架设施遮荫问题,通过测定30°、40°、50°、60°等不同角度栽培装置的光照遮阴变化情况,确定了基于光照因素的最优高架栽培架式角度为50°。为了解决固定式高架设施角... 详细信息

高架设施栽培模式提升了温室作物的产量和质量。为此,针对固定式高架设施遮荫问题,通过测定30°、40°、50°、60°等不同角度栽培装置的光照遮阴变化情况,确定了基于光照因素的最优高架栽培架式角度为50°。为了解决固定式高架设施角度过大、底层作物光照不足等问题,利用温室控温管路系统中水的压力,创新设计了一种以水轮机为动力的自动循环高架装置,分析了结构组成及工作原理,采用SolidWorks软件设计了三维模型。同时,通过Fluent模拟分析不同型号叶轮作用下的水力压力和速度变化,确定了双列直线型六叶轮为最优叶轮选型。装置是以水力产生动力使栽培槽围绕支架匀速转动,为高架设施架式设计提供一种新思路,在创造良好光照条件的同时减少能源的消耗,具有较高的经济效益,在实际生产中具有一定的推广应用价值。

关键词：高架设施栽培装置水力循环优化设计

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Incorporating truncated fractal distribution into Maxwell model to quantify thermal conductivity and its uncertainty in heterogeneous multiparticle systems

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Particuology 2023年第9期80卷 81-89页

作者： j.anting zhu Department of Civil and Architectural Engineering and Construction Management University of WyomingLaramieWY82071USA

An approach is developed to examine the mean and uncertainty of thermal conductivity of a heterogeneous multiparticle system,where the particle concentration or void fraction is treated as a truncated fractal *** truncated fractal distribution is then integrated into the Maxwell model,which is equivalent to a cell model in which the multiparticle system is conceptualized as a spherical fluid cell that envelopes a solid *** developed mean thermal conductivity is compared with four experimental data sets of liquid-saturated media from the *** effect of fractal characteristics is quantified and *** particle concentration or void fraction truncated fractal distribution can better capture scatters in the experimental *** thermal conductivity and its standard deviation decrease with increasing fractal *** the void fraction is truncated fractal,the uncertainty increases mostly in the low mean void fraction range and drops more quickly with the increasing mean void fraction compared to the case where the particle concentration is truncated *** a typical case of multiparticle system when the solid particles are more conductive than the fluid,the faster increase rate of standard deviation with the ratio of solid over fluid conductivities occurs when the mean void fraction is smaller.

关键词： Thermal conductivity Heterogeneous multiparticle system Truncated fractal distribution Particle concentration Void fraction

使用合规农药能确保农产品“地头”质量安全吗?——基于豇豆农户的扎根理论分析

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海南大学学报（人文社会科学版） 2025年第1期43卷 119-128页

作者：樊孝凤张娇朱月季海南大学国际商学院海南海口570228

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析... 详细信息

新的农产品质量安全法首次将小农户施药行为纳入监管范围,进一步厘清农户施药行为的影响机理与因素,有助于政府精准施策。通过对海南3个村32户农民豇豆种植过程的全程蹲点跟踪,对豇豆施药环节的参与式观察与深度访谈,运用扎根理论分析了访谈资料。研究发现:农户施药环节是一个复杂的行为选择过程,即使施用合规农药也不能确保农产品在产地的质量安全。在合规农药视角下影响农户施药行为选择的最重要因素是信息渠道,其次是农产品质量安全管理的政策强度、农产品市场价格和农村劳动用工成本。同时,邻里效应在农户施药行为选择中的作用越来越弱。在此基础上提出,要增加农户用药信息的有效供给渠道,加强农产品质量安全的全面检测,坚持为农户提供形式多样的有针对性的有效培训,增加重要食用农产品质量安全关键技术供给与推广,加强农产品“优质优价”市场建设的政策建议,并进一步指出海南自贸港建设和RECP协议实施背景下提升海南农产品质量安全水平的紧迫性。

关键词：合规农药施药行为农产品质量安全扎根理论

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二维j.nus LuClI的铁谷特性研究

原子与分子物理学报 2025年第2期42卷 159-168页

作者：朱靖欣郭三栋西安邮电大学电子工程学院西安710121

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了j.nus单层LuClI的动力学、力学和热力... 详细信息

铁谷材料由于其固有的铁磁性质,可以产生自发谷极化,从而实现谷自由度的操纵.不同的谷极化状态为铁谷材料在信息传递领域的应用提供了可能性.在本文的工作中,采用了可靠的第一性原理计算方法,证明了j.nus单层LuClI的动力学、力学和热力学稳定性.发现j.nus单层LuClI是一种有潜力的铁谷材料,它有着50.927 meV的谷劈裂.当Lu原子磁矩方向(平面外)发生颠倒时,可以实现谷极化翻转.还计算了j.nus单层LuClI在布里渊区中的Berry曲率分布,主要集中在-K和K谷,可以实现反常谷霍尔效应.当电子关联强度比较小时,j.nus单层LuClI的易磁化轴将指向面内,从而失去自发谷极化.尽管如此,利用应变调控可以使磁化方向从面内转向面外,从而产生谷极化.此外,j.nus单层LuClI同时具有面内和面外压电响应,计算得到的面内压电应变系数d11大于大部分已有二维材料的计算值,而面外压电系数d31非常小.这为通过压电效应调控谷载流子提供了可能性.

关键词：铁谷材料压电第一性原理计算