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农业工程类学科教育与课程整合——庆祝中国农业大学百年校庆(英文)

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中国农业大学学报 2005年第4期10卷 7-12页

作者：张源辉美国Illinois大学农业与生物工程系

农业工程类专业在从农业机械化到农村电气化、从净跨木屋架设计到地下和地表水保护等领域的机械化农业过程中发挥了至关重要的作用。为进一步提高其贡献率和维持其可持续性发展,农业教育工作者应该从农业生产基础的角度对农业工程进行... 详细信息

农业工程类专业在从农业机械化到农村电气化、从净跨木屋架设计到地下和地表水保护等领域的机械化农业过程中发挥了至关重要的作用。为进一步提高其贡献率和维持其可持续性发展,农业教育工作者应该从农业生产基础的角度对农业工程进行再定位。目前:农业工程学科已涉及除机械化生产之外的很多其他方面,例如精准农业、食品加工过程优化、室内和运输车辆内空气质量改善、生物质与生物质能源利用、通过生物过滤与径流控制以减少水体污染等,这些成果正在逐渐成为生物科学及其应用的重点;飞速发展的科学技术已允许我们在全球定位系统中,利用诸如分布式电力供给、纳米技术、生物传感器以及机器人等技术发展精细农业,使得每个动植物个体都可以作为一个实体进行处理以使效益最大化并将环境的负影响降至最低;我们对一些持续的挑战已经有能力应对———例如生物质和生物质能源在科学研究和经济领域内已经获得了新生。为适应那些更加广泛的挑战,我们需要培养相适应的学生和专业人士并使他们学会学习,把不断优化的专业基础知识应用到生产和社会实践中去,做促其高效持续发展的积极推动者。

关键词：农业工程课程生物工程专业

溶剂萃取对螺旋藻水热液化生物原油储存稳定性的影响

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农业工程学报 2023年第5期39卷 175-183页

作者：王影娴曹茂炅张源辉刘志丹兰维娟尹冬雪河南科技大学农业装备工程学院洛阳471000 中国农业大学水利与土木工程学院北京100083 美国伊利诺伊大学香槟校区农业与生物工程系伊利诺伊IL61801

为了研究生物原油所含不同组分对其储存稳定性的影响,该研究提出利用溶剂分步萃取法分离生物原油。采用螺旋藻为原料进行水热液化,利用极性不同的四氢呋喃、乙酸乙酯、丙酮和正己烷为萃取溶剂分离生物原油,以黏度和热值作为稳定性评价指... 详细信息

为了研究生物原油所含不同组分对其储存稳定性的影响,该研究提出利用溶剂分步萃取法分离生物原油。采用螺旋藻为原料进行水热液化,利用极性不同的四氢呋喃、乙酸乙酯、丙酮和正己烷为萃取溶剂分离生物原油,以黏度和热值作为稳定性评价指标,利用热重分析仪、气相色谱质谱联用仪和傅立叶红外光谱仪分析生物原油的老化机理。结果表明:乙酸乙酯萃取得到的生物原油的黏度最低(316 mPa·s),流动性最好,且在储存过程中黏度变化率最小(78.6%),稳定性最好;利用溶剂可以分离生物原油中的重、轻组分和极性、非极性组分,生物原油的老化与极性大分子之间发生的酯化反应、聚合反应密切相关,而小分子非极性化合物的存在可显著降低生物原油的黏度,提高其流动性和稳定性;经储存后生物原油的热值降低了0.4%~6.2%,生物原油的极性组分、重组分和氮元素含量越多,黏度和热值的变化率越大。该研究可为生物质水热液化产物的定向调控及生物原油储存稳定性的提高提供参考。

关键词：稳定性黏度水热液化生物原油溶剂萃取

Multiple processes affecting surface seawater N_2O satura-tion anomalies in tropical oceans and Prydz Bay, Antarc-tica

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Advances in Polar Science 2012年第2期23卷 87-94页

作者： CHEN Liqi ZHAN Liyang XU Suqing zhang Jiexia zhang yuanhui XU Guojie Key Laboratory of Global Change and Marine-Atmospheric Chemistry State Oceanic Administration(SOA)Xiamen 361005China Third Institute of Oceanography SOAXiamen 361005China

We analyzed the N20 content of surface seawater sampled from Prydz Bay, Antarctica, on a cruise track between 30°S and 30°N during the twenty-second Chinese National Antarctic Research Expedition during austral summer, 2006. The surface water showed an average pN20 value of 311.9a：7.6 nL.L-1 （14.1：t：0.4 nmol-Ll）, which was slightly undersaturated. The air-sea N2O flux in the region was -0.3±0.8 ***,dl; howeveh N20 in the surface water was oversaturated in most stations along the cruise track. Saturation anomalies were greater than 10%, with a maximum of 54.7% being observed at the Eqaator, followed by 31% at 10°N in the Sulu Sea. The air-sea fluxes at these locations were 12.4 and 4 μmol-mLd-1, respectively. Overall, the results indicated that surface water in Prydz Bay was near equilibrium with atmospheric N20, and that ocean waters in lower latitudes acted as a N20 source. Physical processes such as stratification, ice-melt water dilution, and solar radiation dominate the factors leading to N20 saturation of surface water of Prydz Bay, while biological production and upwelling are primarily responsible for the N20 oversaturation of surface water observed in subtropical and tropical regions along the cruise track.

关键词： dissolved N20 saturation anomalies tropic subtropic Prydz Bay

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理论计算在药物制剂设计中的研究进展

化工学报 2024年第4期75卷 1429-1438页

作者：张政汪妩琼张雅静王康军吉远辉沈阳化工大学化学工程学院辽宁沈阳110142 江苏省生物药物高技术研究重点实验室东南大学化学化工学院江苏南京211189

药物制剂不仅关系国计民生,而且也是国家安全和科技竞争的战略重点。理论计算在药物制剂设计过程中发挥了重要作用,有关药物制剂设计中的现代理论计算方法一直备受关注。近年来,随着人工智能等新兴技术的飞速发展,药物制剂的研发模式也... 详细信息

药物制剂不仅关系国计民生,而且也是国家安全和科技竞争的战略重点。理论计算在药物制剂设计过程中发挥了重要作用,有关药物制剂设计中的现代理论计算方法一直备受关注。近年来,随着人工智能等新兴技术的飞速发展,药物制剂的研发模式也逐渐向大数据驱动的智能设计模式转变。首先,阐述了理论计算在药物制剂设计中的重要性。然后,重点探讨了药物制剂设计中理论计算的研究现状,分别对分子模拟、热力学计算和人工智能等方法进行了归纳和总结,深入分析了各类方法的优缺点。在此基础上,讨论了理论计算在药物制剂设计中面临的挑战,并对其未来发展方向提出了展望,有望为药物制剂的智能设计提供参考与指导。

关键词：药物制剂理论计算分子模拟热力学计算人工智能

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基于BA优化的多毫米波雷达定位方法

激光杂志 2023年第11期44卷 37-42页

作者：蔚成然刘康张远辉付铎中国计量大学机电工程学院杭州310018

针对使用单个毫米波雷达实现室内环境实时监控和人员跟踪存在障碍物遮挡和覆盖面积有限等问题,提出一种基于多毫米波雷达点云匹配的定位算法。通过前端对行人轨迹聚类拟合配准和后端BA优化定位结果实现雷达间的相互定位,代替仅使用仪器... 详细信息

针对使用单个毫米波雷达实现室内环境实时监控和人员跟踪存在障碍物遮挡和覆盖面积有限等问题,提出一种基于多毫米波雷达点云匹配的定位算法。通过前端对行人轨迹聚类拟合配准和后端BA优化定位结果实现雷达间的相互定位,代替仅使用仪器测量的定位结果。针对毫米波雷达点云边界不明确的问题,通过改进DBSCAN算法进行点云滤波解决。针对雷达间点云匹配关系难以对应问题,提出一种基于拟合路径查找对应点的方法。并提出了一种评估点云配准精度的评价指标。通过多场景的实验对比,提出的定位方法平均精度比测距仪器测量结果提高19%,平均定位精度稳定在0.29 m以内,能够满足室内环境的全覆盖实时监控和行人跟踪的定位需求。

关键词：毫米波雷达点云聚类点云定位 BA优化

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基于单目视觉的移动机器人跟随

仪器仪表学报 2010年第3期31卷 659-664页

作者：虞旦韦巍张远辉上海海事大学物流工程学院上海201306 浙江大学电气工程学院杭州310027

针对室外环境下移动机器人基于单目视觉对目标人实时跟随问题进行了研究,提出通过均值漂移算法对像平面目标的跟踪来实现目标定位。为了补偿摄像机运动造成目标在像平面的偏移,提出了以卡尔曼滤波器的估计值作为均值漂移算法的启动点,... 详细信息

针对室外环境下移动机器人基于单目视觉对目标人实时跟随问题进行了研究,提出通过均值漂移算法对像平面目标的跟踪来实现目标定位。为了补偿摄像机运动造成目标在像平面的偏移,提出了以卡尔曼滤波器的估计值作为均值漂移算法的启动点,然后利用均值漂移算法获得最终位置;为了估计单目视觉下目标与机器人之间的距离,提出了一种借助于主颜色描述子和形状直方图的间接景深计算方法。室外实验表明该算法具有很好的实时性和鲁棒性,能有效实现复杂室外环境下对人的跟随。

关键词：卡尔曼滤波器均值漂移景深主颜色描述子形状直方图

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1373页

作者： Lele REN Wei zhang Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Mechanics Guangxi University Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical Engineering Beijing University of Technology

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell, in cases of 1 : 2 inter-well internal resonance and primary resonance. The transverse foundation excitation is applied to the fixed end of the structure, and the other end is in a free state. The first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control equation. The four-dimensional averaged equations are derived in both polar and rectangular coordinate forms. Deriving from the obtained frequency-amplitude and force-amplitude response curves, a detailed analysis is conducted to examine the impacts of excitation amplitude, damping coefficient, and tuning parameter on the nonlinear internal resonance characteristics of the system. The nonlinear softening characteristic is exhibited in the upper stable-state, while the lower stable-state demonstrates the softening and linearity characteristics. Numerical simulation is carried out using the fourth-order Runge-Kutta method, and a series of nonlinear response curves are plotted. Increasing the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： 74K10 bistable composite laminated cantilever shell chaotic dynamic snap-through complex nonlinear vibration inter-well internal resonance O322 primary resonance