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还原剂和水蒸汽对钯催化nO还原反应性能的影响

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贵金属 2024年第2期45卷 52-58页

作者：吴柄贤王成雄徐滢覃庆高郭律赵云昆昆明贵金属研究所稀贵金属综合利用新技术国家重点实验室昆明650106 昆明贵研催化剂有限责任公司贵金属催化技术与应用国家地方联合工程研究中心昆明650106

为满足严格的排放法规,在控制好nO_(x)排放的同时,也需减少n_(2)O、nH_(3)等二次污染物的排放。为探究尾气组分对nO_(x)还原产物的影响,本文用催化活性模拟评价装置,对自制单钯三效催化剂,进行了还原剂种类、CO浓度及水蒸汽浓度对nO转... 详细信息

为满足严格的排放法规,在控制好nO_(x)排放的同时,也需减少n_(2)O、nH_(3)等二次污染物的排放。为探究尾气组分对nO_(x)还原产物的影响,本文用催化活性模拟评价装置,对自制单钯三效催化剂,进行了还原剂种类、CO浓度及水蒸汽浓度对nO转化效率及n_(2)O和nH_(3)生成产物的影响研究。结果表明,CO催化还原nO是导致n_(2)O生成的主要原因,其内在本质在于催化剂表面活性氧物种的协同作用,nH_(3)的生成量在150~400℃范围内与反应温度正相关;水蒸汽的加入会促进n_(2)O和nH_(3)的生成,H2O分子在催化剂表面吸附作用抑制了活性氧物种的消耗;增加CO浓度可抑制n_(2)O生成但会促进nH_(3)生成。

关键词：单钯催化剂一氧化碳水蒸汽一氧化二氮氨

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A new inclination-based method to evaluate the global geomagnetic configuration and axial dipole moment

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Earth and Planetary Physics 2022年第4期6卷 359-365页

作者： KaiHua Xu Fei He Yong Wei Ross n.Mitchell Si Chen YuQi Wang ZhaoJin Rong Key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China School of Earth and Environment University of LeedsLeedsLS29JTUK

The strength and configuration of the geomagnetic field control the average shape of the *** pure dipole assumption and the virtual dipole moment(VDM),determined by individual records,have been widely adopted to evaluate the strength of the geomagnetic field in geological ***,such an assumption might not be valid during geomagnetic transitions,such as reversals and *** traditional spherical harmonic modeling of the geomagnetic field could be difficult to implement because accurate global records are ***,we report that an empirical relationship exists between the ratio of the VDM to the true axial dipole moment(VDM/ADM)and the ratio of the power of the axial dipole to that of the non-axial dipole(AD/nAD)based on a new method utilizing globally distributed inclination *** root mean square global deviation of inclination(RMSΔI)to the standard inclination distribution of the AD was fitted to the AD/nAD with a cubic polynomial by utilizing a large number of geodynamo *** with geomagnetic field models showed that the AD/nAD derived from the RMSΔI agreed well with that calculated by using the Gauss coefficients,and the estimated ADM was consistent with the true ***,the application of volcanic records during the laschamp excursion showed the VDM might overestimate the ADM by a factor of *** new method will be useful in future studies that characterize the configuration of the geomagnetic field and the strength of the axial dipole.

关键词： axial dipole magnetic inclination virtual dipole moment

Contributions of the receptor for advanced glycation end products axis activation in gastric cancer

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World Journal of Gastroenterology 2023年第6期29卷 997-1010页

作者： Armando Rojas Cristian lindner Iván Schneider Ileana González Miguel Angel Morales biomedical Research laboratories Medicine FacultyCatholic University of MauleTalca 34600000Chile Medicine Faculty Catholic University of MauleTalca 34600000Chile Molecular and Clinical Pharmacology Program Institute of Biomedical SciencesUniversity of ChileSantiago 8320000Chile

Compelling shreds of evidence derived from both clinical and experimental research have demonstrated the crucial contribution of receptor for advanced glycation end products(RAGE)axis activation in the development of neoplasms,including gastric cancer(GC).This new actor in tumor biology plays an important role in the onset of a crucial and long-lasting inflammatory milieu,not only by supporting phenotypic changes favoring growth and dissemination of tumor cells,but also by functioning as a pattern-recognition receptor in the inflammatory response to Helicobacter pylori *** the present review,we aim to highlight how the overexpression and activation of the RAGE axis contributes to the proliferation and survival of GC cells as and their acquisition of more invasive phenotypes that promote dissemination and ***,the contribution of some single nucleotide polymorphisms in the RAGE gene as susceptibility or poor prognosis factors is also discussed.

关键词： Gastric cancer Advanced glycation end-products Receptor of advanced glycation end-products Alarmins Helicobacter pylori Chronic inflammation

高压辊磨强化粗粒铁矿粉制备高品质球团的规律

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中国冶金 2024年第5期34卷 89-97页

作者：吕浩甘敏文小平赵改革谢路奔范晓慧张凯中南大学资源加工与生物工程学院湖南长沙410083 湖南华菱湘潭钢铁有限公司湖南湘潭411101 湘潭瑞通球团有限公司湖南湘潭411101 成都利君实业股份有限公司四川成都610045

利用粗粒铁矿粉替代部分铁精矿生产氧化球团可降低原料成本,然而粗粒铁矿粉中粗颗粒含量高、成球与焙烧性能不佳,导致其制备的球团强度低,因此难以大量配加。研究了高压辊磨预处理对粗粒铁矿粉制备氧化球团的影响。结果表明,高压辊磨后... 详细信息

利用粗粒铁矿粉替代部分铁精矿生产氧化球团可降低原料成本,然而粗粒铁矿粉中粗颗粒含量高、成球与焙烧性能不佳,导致其制备的球团强度低,因此难以大量配加。研究了高压辊磨预处理对粗粒铁矿粉制备氧化球团的影响。结果表明,高压辊磨后粒度大于1 mm粒级的粗粒铁矿粉含量显著降低,微细粒含量增加,比表面积增大;相较于提高辊磨压力,增加辊磨次数更有利于粗颗粒的破碎,此外粗粒铁矿粉的适宜给料水分较低。高压辊磨可以改善颗粒表面性质,增强粗粒铁矿粉的亲水性与成球性,有利于生球质量的提高;同时,在机械力作用下含铁矿物发生晶体活化,当辊磨压力提高至12 MPa以上时机械活化作用更强,这有利于颗粒间固相反应的进行,从而提高球团强度。采用粒度小于1 mm粒级的粗粒铁矿粉进行球团试验,与未处理的粗粒铁矿粉相比,经辊磨压力14 MPa、给料水分(质量分数)3.5%、两次开路辊磨处理后,在相同的球团制备工艺下,粗粒铁矿粉配比(质量分数)可由15%提高至30%;当保持粗粒铁矿粉配比为15%时,焙烧球强度可提高589 n/个。研究结果为拓宽球团原料种类、降低预处理能耗与球团成本提供了理论和技术指导。

关键词：粗粒铁矿粉高压辊磨机械活化氧化球团抗压强度

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一种紫斑牡丹全花茶的制作工艺研究

保鲜与加工 2024年第1期24卷 42-47页

作者：吕小旭黄文迪魏思宇王大成江龙龙关鉴茹甘肃医学院甘肃平凉744000 兰州新区农业科技开发有限责任公司甘肃兰州730000

为开发提升紫斑牡丹市场价值,研究紫斑牡丹全花茶制作工艺。通过清理、护型、干燥等方法对紫斑牡丹全花进行加工,研究了烘干、微波干燥以及真空冷冻干燥方法对紫斑牡丹全花的干燥效果,从紫斑牡丹全花的色泽、形态、气味比较不同制作工艺... 详细信息

为开发提升紫斑牡丹市场价值,研究紫斑牡丹全花茶制作工艺。通过清理、护型、干燥等方法对紫斑牡丹全花进行加工,研究了烘干、微波干燥以及真空冷冻干燥方法对紫斑牡丹全花的干燥效果,从紫斑牡丹全花的色泽、形态、气味比较不同制作工艺,并测定最佳工艺下紫斑牡丹全花茶的营养成分。结果表明:选择初花期的紫斑牡丹全花,以纸杯护型的方法采用真空冷冻干燥法进行干燥,以程序为冷冻阶段-40℃,9.25 h→-30℃,3 h→-20℃,2 h→-10℃,1.5 h,升华干燥阶段0℃,2.5 h→5℃,2.5 h→10℃,2 h→15℃,2 h→20℃,2 h→30℃,2 h→35℃,2 h→40℃,5 h制得的全花茶效果最佳,其全花色泽靓丽、形态挺立,花茶口感醇正、感官评价高,营养成分丰富,其中可溶性蛋白、总酚、总黄酮、VC及亚麻酸等主要营养成分的含量均高于其他干燥工艺制作的牡丹花茶。

关键词：紫斑牡丹全花茶真空冷冻干燥

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柱前荧光衍生化法检测降尘样品中的不饱和醛

分析科学学报 2024年第2期40卷 153-158页

作者：黄露杰徐静汪耀吕敏崔玉洁何振宇林亚维武汉理工大学化学化工与生命科学学院湖北武汉430070 武汉市疾病预防控制中心湖北武汉430060

本研究发展了一种柱前荧光衍生化方法,实现了重要环境污染物不饱和醛类化合物的高灵敏度、高选择性分析。该方法使用4-丁基羟氨-7-羟基香豆素(HAHC)作为荧光衍生试剂,结合高效液相色谱-荧光检测法(HPlC-FlD)实现了6种二烯醛的定性、定... 详细信息

本研究发展了一种柱前荧光衍生化方法,实现了重要环境污染物不饱和醛类化合物的高灵敏度、高选择性分析。该方法使用4-丁基羟氨-7-羟基香豆素(HAHC)作为荧光衍生试剂,结合高效液相色谱-荧光检测法(HPlC-FlD)实现了6种二烯醛的定性、定量分析。在实际样品分析中成功从积尘样品中检测出(E,E)-2,4-庚二烯醛、(E,E)-2,4-辛二烯醛、(E,E)-2,4-十一烷二烯醛。这种柱前衍生化法具有动态范围宽(2~2500nmol/l)、灵敏高(检出限为0.2nmol/l)、精密度好(日内相对标准偏差为2.17%~3.33%,日间相对标准偏差为2.28%~5.04%)等优点,且无需固相萃取等复杂前处理步骤,为痕量醛类污染物检测提供了有效手段。

关键词：硝酮化衍生法不饱和醛高效液相色谱-荧光检测法 4-羟氨基丁基-7-甲氧基-香豆素

An Improved Deep Structure for Accurately brain Tumor Recognition

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Computer Systems Science & Engineering 2023年第8期46卷 1597-1616页

作者： Mohamed Maher Ata Reem n.Yousef Faten Khalid Karim Doaa Sami Khafaga Department of Communications and Electronics Engineering MISR Higher Institute for Engineering and TechnologyMansoura35516Egypt Department of Electronics and Communications Delta Higher Institute for Engineering and TechnologyMansoura35516Egypt Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

brain neoplasms are recognized with a biopsy,which is not commonly done before decisive brain *** using Convolutional neural networks(Cnns)and textural features,the process of diagnosing brain tumors by radiologists would be a noninvasive *** paper proposes a features fusion model that can distinguish between no tumor and brain tumor types via a novel deep learning *** proposed model extracts Gray level Co-occurrence Matrix(GlCM)textural features from MRI brain tumor ***,a deep neural network(Dnn)model has been proposed to select the most salient features from the ***,it manipulates the extraction of the additional high levels of salient features from a proposed Cnn ***,a fusion process has been utilized between these two types of features to form the input layer of additional proposed Dnn model which is responsible for the recognition *** common datasets have been applied and tested,br35H and FigShare *** first dataset contains binary labels,while the second one splits the brain tumor into four classes;glioma,meningioma,pituitary,and no ***,several performance metrics have been evaluated from both datasets,including,accuracy,sensitivity,specificity,F-score,and training *** results show that the proposed methodology has achieved superior performance compared with the current state of art *** proposed system has achieved about 98.22%accuracy value in the case of the br35H dataset however,an accuracy of 98.01%has been achieved in the case of the FigShare dataset.

关键词： brain tumor convolutional neural network gray level co-occurrence matrix noninvasive FigShare dataset br35H dataset

Assessment of Climate Change Impact on Water Requirement and Rice Productivity

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Rice science 2023年第4期30卷 276-293页

作者： Konan Jean-Yves n’GUESSAn botou ADAHI Arthur-brice KOnAn-WAIDHET Satoh MASAYOSHI nogbou Emmanuel ASSIDJO Environmental Training and Research Unit Laboratory of Environmental Sciences and TechnologiesUniversitéJean Lorougnon GuédéBP 150 DaloaCôte d’Ivoire Department of Training and Research of Rural Engineering and Geographic Sciences Institut National Polytechnique FÉLIX HOUPHOUËT-BOIGNYBP 1093 YamoussoukroCôte d’Ivoire University of Tsukuba Ibaraki 305-8577Japan Department of Training and Research of Chemical and Food Engineering Laboratory of ModellingInformation and ProcessesInstitut National Polytechnique FÉLIX HOUPHOUËT-BOIGNYBP 1093 YamoussoukroCôte d’Ivoire

Assessing the impact of climate change(CC)on agricultural production systems is mainly done using crop models associated with climate model *** review is one of the few,with the main objective of providing a recent compendium of CC impact studies on irrigation needs and rice yields for a better understanding and use of climate and crop *** discuss the strengths and weaknesses of climate impact studies on agricultural production systems,with a particular focus on uncertainty and sensitivity analyses of crop *** the new generation global climate models(GCMs)are more robust than previous ones,there is still a need to consider the effect of climate uncertainty on estimates when using *** GCMs cannot directly simulate the agro-climatic variables of interest for future irrigation assessment,hence the use of intelligent climate ***,sensitivity and uncertainty analyses must be applied to crop models,especially for their calibration under different *** impacts of CC on irrigation needs and rice yields vary across regions,seasons,varieties and crop ***,integrated assessments,the use of remote sensing data,climate smart tools,CO_(2)enrichment experiments,consideration of changing crop management practices and multi-scale crop modeling,seem to be the approaches to be pursued for future climate impact assessments for agricultural systems。

关键词： climate change rice production irrigation crop model climate model

Effects of plating factors on morphology and appearance of electrogalvanized steel sheets

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中国有色金属学会会刊：英文版 2009年第4期19卷 835-841页

作者： Hiroaki n AKAnO Department of Materials Science and Engineering Faculty of EngineeringKyushu University

because the lightness,the gloss and the press-formability of electrogalvanized steel sheets change depending on the morphology of deposited Zn,control of this factor is essential to improving these *** effects of plating factors on the morphology of deposited Zn were systematically discussed both from the crystallographic viewpoint of epitaxy between Zn and steel and from the electrochemical viewpoint of the overpotential for Zn *** factors include crystal orientation of steel substrate,current density,flow rate,temperature,addition of inorganic compounds to the solution and pre-adsorption of organic *** plating factors affect the overpotential for Zn deposition and epitaxy between Zn and *** crystal orientation index of the Zn basal plane and the platelet crystal size of Zn are decreased with increasing the overpotential for Zn *** are also decreased with decreasing the epitaxy between Zn and steel,even when the overpotential is kept *** the overpotential for Zn deposition is increased,the surface roughness of deposited Zn increases because of an increase in the inclination of the Zn basal plane to the steel *** the epitaxy between Zn and steel is decreased without changing the overpotential,the surface roughness is reduced due to the decrease in platelet crystal size of Zn,although the inclination of the Zn basal plane is somewhat *** lightness of deposited Zn is enhanced with decreasing the surface roughness of Zn.

关键词：电镀锌钢板外观形态