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钨硅分子筛中钨的配位结构及其催化油酸甲酯氧化裂解性能

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石油学报（石油加工） 2024年第2期40卷 349-358页

作者：辛世豪彭欣欣邢恩会张耀黄作鑫舒兴田中石化石油化工科学研究院有限公司北京100083

通过后合成法和水热合成法分别制备了w-Beta分子筛和w-MFI分子筛,采用X射线衍射(XRD)、N_(2)低温吸附-脱附、紫外-可见光谱(UV-Vis)、红外光谱和冷喷雾离子质谱(CSI-MS)等手段表征了钨硅分子筛的钨配位状态以及滤液的离子结构,考察了钨... 详细信息

通过后合成法和水热合成法分别制备了w-Beta分子筛和w-MFI分子筛,采用X射线衍射(XRD)、N_(2)低温吸附-脱附、紫外-可见光谱(UV-Vis)、红外光谱和冷喷雾离子质谱(CSI-MS)等手段表征了钨硅分子筛的钨配位状态以及滤液的离子结构,考察了钨硅分子筛的催化油酸甲酯氧化裂解活性及稳定性,并与滤液催化活性进行了关联。结果表明:水热法合成w-MFI分子筛中四面体wO_(2)(OSi)_(2)稳定性好,具有催化环氧化活性,无催化氧化裂解活性;后合成法制备的w-Beta分子筛中,钨物种与脱铝产生的分子筛硅羟基相互作用形成纳米wO_(3)团簇,提高了催化氧化裂解活性,但稳定性差;分子筛上wO_(3)与H_(2)O_(2)反应生成宽质/荷比分布的均相过氧钨酸根阴离子,具有催化氧化裂解活性。

关键词：钨硅分子筛配位结构合成法油酸甲酯催化氧化裂解 H_(2)O_(2)

Locally enhanced electric field treatment (LEEFT) for water disinfection

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Frontiers of Environmental Science & Engineering 2020年第5期14卷 25-36页

作者： Jianfeng Zhou Ting w.ng Cecilia Yu xing Xie School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

water disinfection is a critical step in water and wastewater *** most widely used chlorination suffers from the formation of carcinogenic disinfection by-products(DBPs)while alternative methods(e.g.,UV,O3,and membrane filtration)are limited by microbial regrowth,no residual disinfectant,and high operation ***,a nanowire-enabled disinfection method,locally enhanced electric field treatment(LEEFT),is introduced with advantages of no chemical addition,no DBP formation,low energy consumption,and efficient microbial *** to the lightning rod effect,the electric field near the tip area of the nanowires on the electrode is significantly enhanced to inactivate microbes,even though a small external voltage(usuallyw,after emphasizing the significance of water disinfection,the theory of the LEEFT is ***,the recent development of the LEEFT technology on electrode materials and device configurations are *** disinfection performance is analyzed,with respect to the operating parameters,universality against different microorganisms,electrode durability,and energy *** studies on the inactivation mechanisms during the LEEFT are also ***,the challenges and future research of LEEFT disinfection are discussed.

关键词： water treatment Nanotechnology Pathogen inactivation Electroporation Nanowire Chemical-free

Control of water contamination on side window of road vehicles by A-pillar section parameter optimization

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Journal of Hydrodynamics 2020年第6期32卷 1138-1150页

作者： Li Xin xing-jun Hu Jing-yu w.ng State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun130025China

The water contamination on the side windows of moving vehicles is a crucial issue in improving the driving safety and the *** this paper,an effective optimization method is proposed to reduce the water contamination on the side windows of *** accuracy and the efficiency of the numerical simulation are improved by using the lattice Boltzmann method,and the Lagrangian particle tracking *** parameters are constructed on the basis of the occurrence of the water deposition on a vehicle’s side *** water contamination area of the side window and the aerodynamic drag are considered simultaneously in the design process;these two factors are used to form the multi-objective optimization function in the genetic algorithm(GA)*** approximate model,the boundary-seeded domain method,and the GA method are combined in this study to enhance the optimization *** optimization,the optimal parameters for the A-pillar section are determined by setting the boundary to an area of w=7.77 mm,L=1.27 mm and H=11.22 *** side window’s soiling area in the optimized model is reduced by 66.93%,and the aerodynamic drag is increased by 0.41%only,as compared with the original *** is shown that the optimization method can effectively solve the water contamination problem of side windows.

关键词： water contamination aerodynamic drag A-pillar section parameters multi-objective optimization approximate model genetic algorithm

Probabilistic model of disc-cutter wear in TBM construction:A case study of Chaoer to Xiliao water conveyance tunnel in China

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Science China(Technological Sciences) 2023年第12期66卷 3534-3548页

作者： YAng wenKun CHEN ZuYu wU GenSheng xing Hai School of Civil Engineering Institute of Future Underground SpaceSoutheast UniversityNanjing 211189China Department of Geotechnical Engineering China Institute of Water Resources and Hydropower ResearchBeijing 100038China Sinohydro Bureau 6 Co. Ltd.Shenyang 110179China

Disc-cutters play a crucial role in the penetration process during construction using a tunnel boring machine(TBM).Their wear status has a significant impact on working efficiency and costs that accounts for a large part of the *** the wear pattern and characteristics of disc-cutters could provide a valuable guide for field maintenance and cutter replacement *** also provides insight into the wear mechanism of cutters at different positions for optimizing the disc-cutter arrangement *** this study,the cutter wears data of 34 disc-cutters over 643 days in the Chaoer River to Xiliao River water diversion tunnel was *** dataset contains 21862 manual readings measured from 1079 disc-cutters replaced in this *** raw data from the hard copy version was transformed into a digital twin database by eliminating abnormal data,filling in empty values,and performing linear *** has been found that the cutters can pass statistical testing for an exponential probability distribution function with respect to the wear rate(w).The regression ratios of R2are essentially greater than *** findings would help estimate the future service life of a currently working cutter,which means significant savings for the costly *** application of exponential distribution has the advantage of only one shape parameter,λ,whose reciprocal represents both the statistical mean and standard deviation of the wear *** is simple and practically amenable.A preliminary study was carried out to simulate the wear process between two neighboring cutters for drafting a replacement plan for disc-cutters by the Monte Carlo *** prediction results agreed reasonably well with the measured information.

关键词： tunnel boring machine disc-cutter wear wear rate probability model

梯度升温发酵工艺对不同盐分稀态发酵酱油微生物变化和风味形成的影响

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食品工业科技 2024年第9期45卷 106-114页

作者：李心智刘希徐新玉周其洋吴昌正童星欧仕益暨南大学食品科学与工程系广东广州510632 佛山市海天调味食品股份有限公司广东佛山528000 佛山市海天(高明)调味食品有限公司广东佛山528511 广东海天创新技术有限公司广东佛山528000 广东省调味食品生物发酵先进技术企业重点实验室广东佛山528000 广东省酿造微生物育种与发酵工程技术研究中心广东佛山528000

本文以12%和18%(w/v)两种盐分浓度的稀态发酵酱醪为研究对象,探究梯度升温(15℃-20℃-25℃-30℃)工艺对发酵酱醪微生物计数和风味形成的影响。结果显示:采用梯度升温工艺的低盐分酱醪样品(TC12)的酵母计数在发酵到期时比恒温(30℃)对照... 详细信息

本文以12%和18%(w/v)两种盐分浓度的稀态发酵酱醪为研究对象,探究梯度升温(15℃-20℃-25℃-30℃)工艺对发酵酱醪微生物计数和风味形成的影响。结果显示:采用梯度升温工艺的低盐分酱醪样品(TC12)的酵母计数在发酵到期时比恒温(30℃)对照组(C12)要高1.0 log CFU/g左右,这表明酵母在梯度升温工艺中维持生长代谢时间较长。这或与发酵前期较低的温度限制了酵母过快的繁殖有关。其中,TC12的发酵到期原油的氨基酸态氮高达1.14 g/100 g,达到我国规定的特级酿造酱油标准。同时,TC12中的鲜味(19.03 g/L)和甜味氨基酸(19.32 g/L)含量较高,共占氨基酸总量约60%,呈现较好的鲜甜滋味。挥发性物质检测数据显示,TC12中的乙醇、苯乙酸乙酯、棕榈酸乙酯、3-甲硫基丙醛和苯甲醛等含量较高,样品整体呈现“水果甜香和酯香”。另一方面,高盐组梯度升温样品(TC18)则测得更多的愈创木酚和甲基麦芽酚,呈现“烟熏香和酱香”。感官鉴评数据显示,低盐分梯度升温发酵样品TC12相比恒温发酵组C12具有更高的香气和滋味得分,综合口感更优。综上所述,梯度升温工艺有利于限制低盐分(12%)发酵酱醪中酵母在前期的过快生长,保持其在发酵后期的活性细胞计数,使其能持续发酵生成更多风味物质,提升低盐发酵原油的整体风味。

关键词：梯度升温低盐发酵酱油酵母氨基酸态氮游离氨基酸挥发性风味物质

基于RAA-CRISPR/Cas12a技术的桃成分单管一体化快速检测方法

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食品科学 2024年第21期45卷 280-287页

作者：王琳邢冉冉于耀鲜易秋菊卢思远邓婷婷王旭陈颖中国检验检疫科学研究院北京100176 天津科技大学食品科学与工程学院天津300457

通过设计特异性的桃重组酶介导的等温扩增(recombinase-aided amplification,RAA)和CRISPR RNA(crRNA)引物,建立RAA技术结合CRISPR/Cas12a系统的单管一体化桃成分快速检测方法,并分析该方法的特异性、灵敏度和检出限,同时对市售样品进... 详细信息

通过设计特异性的桃重组酶介导的等温扩增(recombinase-aided amplification,RAA)和CRISPR RNA(crRNA)引物,建立RAA技术结合CRISPR/Cas12a系统的单管一体化桃成分快速检测方法,并分析该方法的特异性、灵敏度和检出限,同时对市售样品进行检测。结果显示,该方法不依赖大型仪器设备,在30 min内即可完成桃成分的快速检测;与其他常见水果物种之间无交叉污染,表现出良好的特异性;该方法的灵敏度为1.0×10-1 ng/μL;检出限为1%;通过对20份市售样品检测,结果显示本方法与实时聚合酶链式反应法检测结果一致。因此,本研究建立的RAA-CRISPR/Cas12a单管一体化桃成分快速检测方法具有特异性好、灵敏度高的优点,为桃成分快速检测提供了一种新的技术。

关键词：重组酶介导的等温扩增 CRISPR/Cas12a 单管一体化桃成分快速检测

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山地蕉无人机自主吊运装置研制

农业工程学报 2024年第15期40卷 1-10页

作者：段洁利李伟希李伟钦徐兴余家祥丁炜妮杨洲华南农业大学工程学院广州510642 岭南现代农业科学与技术广东省实验室广州510600 广东海洋大学机械工程学院湛江524088

针对目前山地蕉采后运送作业主要依靠人工背运,存在劳动强度大、人力成本高、果实容易损伤以及易发生安全事故等问题,该研究设计了一种山地蕉无人机自主吊运装置,能够实现无人机山地蕉吊运过程中对果轴的自主抓取和卸载,减少人工参与,... 详细信息

针对目前山地蕉采后运送作业主要依靠人工背运,存在劳动强度大、人力成本高、果实容易损伤以及易发生安全事故等问题,该研究设计了一种山地蕉无人机自主吊运装置,能够实现无人机山地蕉吊运过程中对果轴的自主抓取和卸载,减少人工参与,保障作业人员安全。基于测定的山地蕉蕉穗形态特征参数设计抓取机构、吊具、导向机构以及连接件等,并通过SOLIDwORKS软件建立装置的三维模型,同时搭建了上下位机通讯系统。基于ANSYS workbench软件的显式动力学分析(explicit dynamics)、静磁分析(magnetostatic)对吊运装置的关键零部件进行仿真和理论计算,确定满足使用要求的电磁铁与舵机型号及参数。室内试验表明,装置的果轴平均抓取成功率为92.59%,果轴平均卸载成功率为96%,平均吊运成功率为88.89%,抓取与卸载的平均耗时分别为63.8和20.8 s/次。无人机搭载吊运装置进行田间试验,平均吊运成功率为83.33%,抓取与卸载平均总耗时90.8 s/次,平均吊运速度0.99 m/s,是人工背运速度(0.17~0.33 m/s)的3倍以上,且由于蕉穗悬空在吊运装置下方不与其他物体接触从而不会对果指造成损伤,满足无人机自主吊运山地蕉的作业需求。研究结果可为快速、低损、安全的无人机山地蕉吊运装置设计提供参考,促进香蕉产业的高质量发展。

关键词：农业机械无人机香蕉吊运装置山地蕉园仿真分析

三十烷醇纳米制剂对冬小麦抗旱生理特性的影响

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干旱地区农业研究 2024年第1期42卷 142-151页

作者：张鑫王崇李丽王超马海洋邢佳伊王耀生中国农业科学院农业环境与可持续发展研究所/作物高效用水与抗灾减损国家工程实验室/农业农村部旱作节水农业重点实验室北京100081

以‘XR4347’品种冬小麦为供试作物,在步入式气候室内开展盆栽试验,设置3种叶面喷施剂型和3个灌溉水平,剂型为市售三十烷醇微乳剂(TRIA,T1)、水滑石负载三十烷醇纳米制剂(TRIA-LDH,T2)和助剂条件对照(T3);灌溉水平分别设置为土壤田间持... 详细信息

以‘XR4347’品种冬小麦为供试作物,在步入式气候室内开展盆栽试验,设置3种叶面喷施剂型和3个灌溉水平,剂型为市售三十烷醇微乳剂(TRIA,T1)、水滑石负载三十烷醇纳米制剂(TRIA-LDH,T2)和助剂条件对照(T3);灌溉水平分别设置为土壤田间持水量的90%(充分灌溉,w1)、60%(中度水分胁迫,w2)和40%(重度水分胁迫,w3)。结果表明:(1)在相同水分处理下,喷施TRIA和TRIA-LDH对小麦叶片光合速率有促进作用。中度水分胁迫下,喷施TRIA和TRIA-LDH的小麦地上部干质量较对照处理分别增加69.9%和32.7%,水分利用效率分别增加32.2%和16.4%;重度水分胁迫下,喷施TRIA-LDH的小麦耗水量比喷施TRIA显著降低24.0%,地上部干物质积累量增加,因此水分利用效率显著提高13.6%。(2)中度水分胁迫下喷施TRIA-LDH的小麦叶片过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性比喷施TRIA处理显著增加2倍,重度水分胁迫下喷施TRIA-LDH的小麦叶片SOD活性比喷施TRIA处理显著增加1倍,表明喷施TRIA-LDH比喷施TRIA对抗氧化酶活性的促进效果更好。(3)重度水分胁迫下,喷施TRIA-LDH与TRIA的小麦叶片ABA含量分别比对照处理显著降低21.8%和30.9%,表明重度水分胁迫下外源施用三十烷醇可通过降低叶片ABA含量有效缓解水分胁迫对于植株生长的抑制。(4)重度水分胁迫下,喷施TRIA的小麦叶片保卫细胞Ca^(2+)大量外流,而喷施TRIA-LDH的叶片保卫细胞Ca^(2+)内流,可见植物对TRIA-LDH的吸收利用效果更好。在水分胁迫下,三十烷醇纳米制剂增强了植株的抗旱能力,提高了植株的水分利用效率。因此,水滑石纳米载体可用于负载三十烷醇,实现三十烷醇对植物高效、可持续的调控。

关键词：三十烷醇水滑石纳米载体冬小麦水分利用效率抗旱性

Sustainable Development from the Philosophical Perspective——Introspection of Human Existence

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学术界 2014年第12期 308-312页

作者： xing Huirong College of Marxism Shandong University of Finance

Sustainable development has already been carried out in social practice,and only by starting from social practice can we have a better understanding not only of the subject of sustainable development,i. e.,human beings,but also of human existence and sustainable development itself. Based on the survey of human beings and human existence,this paper analyzes the inner contradiction of sustainable development and researches human existence in the developmental practice. Human beings exist in the flow of time,for whom sustainability is the basic desire. At the same time,human existence and human development are closely related to each other,and development is the dynamic manifestation of existence. T he development of human beings is an important part and core value of sustainable development and it is also the realization of the freedom of human existence.

关键词： sustainable development human existence reform existence co-existence