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基于Marchenko理论的成像域与数据域层间多次波消除方法对比

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地球物理学报 2022年第4期65卷 1416-1424页

作者：张乐乐邵婕郑忆康王一博 evert slob 中国地质大学地球物理与空间信息学院地球内部多尺度成像湖北省重点实验室武汉430074 中国科学院地质与地球物理研究所北京100029 Delft University of Technology 2628 CN DelftThe Netherlands

Marchenko成像可以理解为一种基于Marchenko理论的成像域层间多次波消除方法.该方法利用Marchenko方程组将地表观测的地震数据准确的延拓到地下的成像点,得到震源位于地下成像点、检波点位于地表的上下行格林函数,进而采用多维反褶积获... 详细信息

Marchenko成像可以理解为一种基于Marchenko理论的成像域层间多次波消除方法.该方法利用Marchenko方程组将地表观测的地震数据准确的延拓到地下的成像点,得到震源位于地下成像点、检波点位于地表的上下行格林函数,进而采用多维反褶积获得该成像点不含多次波假象的像.基于Marchenko方程组所推导出的数据域多次波消除方法可以准确的预测并消除所有阶数的层间多次波.该方法不需要任何速度信息和匹配相减,避免了传统多次波消除方法对一次波造成的损害.基于数据域多次波消除之后的数据,可以获得地下结构不含多次波假象的像.本文对基于Marchenko理论的成像域及数据域层间多次波消除方法进行了对比分析,给出了详细的理论及数值模型试算结果,并对两种方法的优缺点进行了讨论.

关键词： Marchenko方程组层间多次波多次波消除多维反褶积

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利用阵列感应测井进行储层渗透率评价

地球物理学报 2016年第11期59卷 4360-4371页

作者：周峰孟庆鑫胡祥云 evert slob 潘和平马火林中国地质大学(武汉)机械与电子信息学院武汉430074 中国地质大学(武汉)地球物理与空间信息学院地球内部多尺度成像湖北省重点实验室武汉430074 河北地质大学勘查技术与工程学院石家庄050031 代尔夫特理工大学土木与地球科学学院

钻井过程中储层受到泥浆侵入影响的程度与储层岩性有着密切关系,其中储层渗透率对侵入深度有着较大影响,因此若可以获知泥浆侵入深度,则有望对储层渗透率进行评估.本文首先建立含泥饼增长的泥浆侵入数值模型,然后建立阵列感应测井数值模... 详细信息

钻井过程中储层受到泥浆侵入影响的程度与储层岩性有着密切关系,其中储层渗透率对侵入深度有着较大影响,因此若可以获知泥浆侵入深度,则有望对储层渗透率进行评估.本文首先建立含泥饼增长的泥浆侵入数值模型,然后建立阵列感应测井数值模型,两者的联合正演模拟显示泥浆侵入对地层的影响可以反映在阵列感应测井响应上,利用阻尼最小二乘法对阵列感应测井响应进行反演可以得到侵入深度.对侵入深度和储层渗透率的关系进行分析发现:在渗透率为1～100mD(1mD=0.987×10^(-3)μm～2)数量级的储层中,渗透率的变化可以在侵入深度上得到反映.以储层和井数据进行二维数值模拟发现:利用阵列感应测井响应反演出来的侵入深度曲线反映了渗透率在地层上的变化趋势,采用解释图版的方法可以对储层各层段的渗透率进行粗略估算.

关键词：阵列感应测井渗透率评价泥浆侵入

Helmholtz equation and non-singular boundary elements applied to multi-disciplinary physical problems

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Communications in Theoretical Physics 2022年第8期74卷 18-34页

作者： evert Klaseboer Qiang Sun Institute of High Performance Computing 1 Fusionopolis WaySingapore 138632Singapore Australian Research Council Centre of Excellence for Nanoscale BioPhotonics School of ScienceRMIT UniversityMelbourneVIC 3001Australia

The famous scientist Hermann von Helmholtz was born 200 years *** complex physical wave phenomena in engineering can effectively be described using one or a set of equations named after him:the Helmholtz *** this has been known for a long time,from a theoretical point of view,the actual numerical implementation has often been hindered by divergence-free and/or curlfree *** is further a need for a numerical method that is accurate,reliable and takes into account radiation conditions at *** classical boundary element method satisfies the last condition,yet one has to deal with singularities in the *** review here how a recently developed singularity-free three-dimensional boundary element framework with superior accuracy can be used to tackle such problems only using one or a few Helmholtz equations with higher order(quadratic)elements which can tackle complex curved *** are given for acoustics(a Helmholtz resonator among others)and electromagnetic scattering.

关键词： acoustics Helmholtz cavity electromagnetics scattering boundary integral method

Boundary layer influence on ship model tests in extremely shallow and confined water

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Journal of Hydrodynamics 2023年第2期35卷 365-378页

作者： evert Lataire Asif Raza Marc Vantorre Guillaume Delefortrie Maritime Technology Division Ghent UniversityGhentBelgium ANAST University of LiègeLiègeBelgium Flanders Hydraulics Research AntwerpBelgium

Ships sailing in shallow and/or confined water(when calling a harbour or other berthing areas),will experience a different behaviour due to the interaction with vertical and/or horizontal *** other hydrodynamic changes induced in confined water,the lateral ship-bank interaction force changes its sign at a critical distance between ship and bank or ***,this distance and its effects on model test results have not been quantified in the *** investigate the shallow water hydrodynamics coupled with bank effects,systematic model tests were carried out at Flanders Hydraulics Research(FHR)with different ship *** following parameters were systematically varied:water depth,lateral position,speed,and propeller *** change of the ship-bank induced lateral force from an attraction force in medium-deep and shallow water to a repulsion force in extremely shallow water conditions,can be ascribed to the interaction of the boundary layers of the ship model and the environment(tank and installed banks).In this article,a mathematical model is proposed for the critical distance in terms of boundary layer influence *** indicates the range where the model tests are influenced by the horizontal or vertical restrictions combined with the propeller’s dynamic ***,the expression has also been extended to describe the relationship between full-scale ship length and water depth with the boundary layer influence *** to lower Reynolds numbers and relatively thicker boundary layers at model scale,upscaling of the model test results,according to Froude’s law,may provide erroneous *** influence of the boundary layer initiates at a relatively higher under keel clearance(UKC)for a smaller ship model compared with a larger ship ***,the boundary layer’s influence with respect to ship model length should be considered during model testing.

关键词： Shallow water hydrodynamics bank effects boundary layer model tests mathematical model

Key factors determining biochar sorption capacity for metal contaminants:a literature synthesis

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Biochar 2020年第2期2卷 151-163页

作者： evert Thomas Nils Borchard Christian Sarmiento Rachel Atkinson Brenton Ladd Bioversity International c/o CIP Avenida La Molina 1895La MolinaLima 12Peru Natural Resources Institute Finland(Luke) Latokartanonkaari 900790 HelsinkiFinland Facultad de Ciencias Ambientales Universidad Científica del SurLima 33Peru

The sorption capacity and affinity of biochar for metals are both important attributes that determine biochar’s suitability as a soil amendment for contaminant mitigation,yet few analyses have considered both characteristics *** present a systematic review of literature published between 2010 and 2018 to test the hypothesis that sorption capacity and affinity are affected by biochar properties,attributes of the metal contaminant,and experimental conditions,in that *** used random forest(RF)and multi-objective optimization to analyze data of 559 individual Langmuir adsorption isotherms extracted from 133 studies covering the sorption capacity(C_(max))and affinity(K_(L))of biochar for 17 different metals,elabo-rated from six different feedstock classes,three different types of feedstock pretreatment,and five types of post-pyrolysis *** sorption values were obtained for Pb(II),Cr(IV),and Cd(II).The feedstock used was the key determinant influencing biochar’s capacity and affinity to sorb metal contaminants(first and fourth most important variable in RF mod-els for C_(max) and K_(L),respectively)with best results obtained for biochar elaborated from nutrient-dense feedstocks(animal biowaste,sludge,and manure).Biochars that had both high sorption capacity and affinity were the result of a longer dura-tion of pyrolysis;they had lower C and higher N and O content,as well as lower C/N and higher O/C and H/C ratios,higher pore volumes and higher *** some form of pretreatment was better than none,whereas chemical modification was the best of the post-treatment methods *** review demonstrates clearly that multiple parameters during the preparation process influence the effectiveness of biochar to immobilize metal *** research that focuses on mechanisms and the underlying factors for the correlations observed should allow the development of biochar formulations that are even more effective at immobilizing metal

关键词： Biochar Sorption affinity Maximum sorption capacity Metal Aluminum Arsenic Langmuir absorption coefficients

微米及纳米丝光沸石分子筛上二甲醚羰基化反应的积碳分析

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催化学报 2013年第8期34卷 1496-1503页

作者：薛会福黄秀敏 evert Ditzel 展恩胜马猛申文杰中国科学院大连化学物理研究所催化基础国家重点实验室辽宁大连116023 Hull Research and Technology Centre BP Chemicals LimitedHull HU128DSUK

对比研究了在传统微米尺寸和新结构纳米丝光沸石催化剂上二甲醚羰基化合成乙酸甲酯的反应行为. 结果表明, 通过减小分子筛的尺寸到纳米水平, 可以有效提高反应物和产物到达或者脱离反应活性位的效率, 从而提高了二甲醚的转化率; 更重要... 详细信息

对比研究了在传统微米尺寸和新结构纳米丝光沸石催化剂上二甲醚羰基化合成乙酸甲酯的反应行为. 结果表明, 通过减小分子筛的尺寸到纳米水平, 可以有效提高反应物和产物到达或者脱离反应活性位的效率, 从而提高了二甲醚的转化率; 更重要的是, 抑制了硬积碳的生成, 使催化剂保持了更高的稳定性.

关键词：氢型丝光沸石二甲醚羰基化晶体尺寸积碳

B Vitamins Can Reduce Body Weight Gain by Increasing Metabolism-related Enzyme Activities in Rats Fed on a High-Fat Diet

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2018年第1期38卷 174-183页

作者： Ying ZHENG Ai-guo MA Ming-ci ZHENG Qiu-zhen WANG Hui LIANG Xiu-xia HAN evert G.Schouten Department of Nutrition Guangdong General HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China Institute of Human Nutrition Medical College of Qingdao UniversityQingdao 266021China Department of Pediatrics Guilin Medical College Affiliated HospitalGuilin 541001China Division of Human Nutrition Wageningen UniversityWageningen 6700 EVThe Netherland

B vitamins are enzyme cofactors that play an important role in energy *** aim of this study was to elucidate whether B vitamin administration can reduce body weight(BW)gain by improving energy metabolism-related enzyme activities in rats fed on a highfat *** rats were randomly assigned to one of the following five groups:control group(C),including rats fed on standard rat chow;four treatment groups(H0,H1,H2,and H3),in which rats were fed on a high-fat *** in the H1 group were treated daily with 100 mg/kg BW thiamine(VB1),100 mg/kg BW riboflavin(VB2),and 250 mg/kg BW niacin(VPP);rats in the H2 group were treated daily with 100 mg/kg BW pyridoxine(VB6),100 mg/kg BW cobalamin(VB12),and 5 mg/kg BW folate(FA);and rats in the H3 group were treated daily with all of the B vitamins administered to the H1 and H2 *** 12 weeks,the BW gains from the initial value were 154.5±58.4 g and 159.1±53.0 g in the H1 and C groups,respectively,which were significantly less than the changes in the H0 group(285.2±14.8 g,P〈0.05).In the H0 group,the plasma total cholesterol(CHO)and triglyceride(TG)levels were 1.59±0.30 mmol/L and 1.55±0.40 mmol/L,respectively,which were significantly greater than those in the H1 group(1.19±0.18 mmol/L and 0.76±0.34 mmol/L,respectively,P〈0.05).The activities of transketolase(TK),glutathione reductase,and Na^+/K^+adenosine triphosphatase were significantly increased in the B vitamin-treated groups and were significantly greater than those in the H0 group(P〈0.05).Furthermore,the glucose-6-phosphate dehydrogenase,pyruvic acid kinase,and succinate dehydrogenase activities also were increased after treatment with B *** with B vitamins could effectively reduce BW gain and plasma levels of lipids by improving energy metabolism-related enzyme activities in rats,thus possibly providing potential benefits to humans.

关键词： B vitamins obesity body weight gain enzyme activities rats

Seaweeds as Biomonitoring System for Heavy Metal (HM) Accumulation and Contamination of Our Oceans

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American Journal of Plant Sciences 2018年第7期9卷 1514-1530页

作者： Vincent van Ginneken evert de Vries Bluegreen Technologies Heelsum The Netherlands

This research manuscript reports the heavy metal accumulation in four marine seaweeds sp. 1)?Caulerpa sertlatioides (Cuba);2) Caulerpa cf. brachypus;(Bali, Indonesia);3) Undaria pinnatifida (West-Donegal, Ireland);4) Ulva lactuca (Easters-Scheldt, the Netherlands). Mechanical pressure at 10 bar of fresh seaweed fronds casu quo biomass in the laboratory delivered seaweed moisture which was analyzed by Inductively Coupled Plasma Spectroscopy (ICP)-techniques for heavy-metals = [HM], (Al, As, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb & Zn). Three important observations were made: 1) The [HM] in the seaweed moisture is higher than in the surrounding seawater which directs to mechanism(s) of bio-accumulation;2) The accumulation factor [AF] is varying per metallic-cation with an overall trend for our four seaweeds and sampling locations for [HM] are: As & Co & Cu: 5000 - 10,000 μg/l;Ni & Zn: 3000 - 5000 μg/l;Cd: 2000 - 3000 μg/l;Cr: 1000 - 2000 μg/l;Al: 200 - 1000 μg/l;Mo & Pb & Fe: 0 - 200 μg/l range. 3) Seaweed moisture detected that [HM]: Pb & Zn & Fe—which all three could not be detected in the seawater—supports the view that seaweeds have a preference in their bio-accumulation mechanism for these three HM. Major conclusion is in general that “overall” for the macro-elements Ca, Fe, K, Mg, Mn, Na, P & S in the moisture of the four seaweed species the concentration is lower in the seaweed species, or equals the concentration, in comparison to the surrounding sea water. For the HM (Al, As, Cd, Co, Cr, Cu, Mo, Ni, Pb & Zn) the opposite is the case species and is the concentration “overall” higher in the seaweed species in comparison to the surrounding sea water. Further topics addressed include strategies of irrigation of the Sahara desert with the moisture out of seaweeds under conditions of low anthropogenic influences.

关键词： Seaweeds Heavy Metal Accumulation Ulva lactuca Caulerpa sertlatioides Caulerpa cf. brachypus & Undaria pinnatifida Inductively Coupled Plasma Spectroscopy (ICP)-Techniques Al As Cd Co Cr Cu Fe Mo Ni Pb & Zn Bio-Accumulation Biomonitoring Upper Tolerance Nutrient Intake Levels (ULs) Irrigation Water

同源转基因将成为利用野生资源进行作物育种的一种有效手段

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园艺学报 2006年第6期33卷 1397-1400页

作者：黄三文杜永臣屈冬玉 evert Jacobsen 中国农业科学院蔬菜花卉研究所北京100081 荷兰瓦赫宁根大学及研究中心植物育种系

作物育种的一个主要限制因素是各栽培种的遗传基础日趋狭窄,迫切需要从野生种质资源中导入优异等位基因。杂交障碍和连锁累赘降低了常规育种利用这些等位基因的效率。基因组研究的发展使得越来越多的植物基因的克隆成为可能。同源转基... 详细信息

作物育种的一个主要限制因素是各栽培种的遗传基础日趋狭窄,迫切需要从野生种质资源中导入优异等位基因。杂交障碍和连锁累赘降低了常规育种利用这些等位基因的效率。基因组研究的发展使得越来越多的植物基因的克隆成为可能。同源转基因就是将本物种或其近缘野生种克隆的优异等位基因导入到要改良的育种材料中。这不仅可以缩短育种的周期,而且不会有不良性状的连锁累赘。同源转基因和常规育种所要导入的目标基因的来源是相同的,因此育成的品种同样是安全的。如果转基因条例能够将同源转基因品种视同为常规育种品种,同源转基因将会成为人们利用野生资源进行作物改良的一种有效手段。

关键词：作物育种同源转基因安全评价