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降压药能与抗ED药物同服吗
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作者 毕瑞 《漫科学(新健康)》 2024年第1期30-31,共2页
高血压作为一种最常见的心血管疾病,与勃起功能障碍(ED)有着密切的联系。根据美国马萨诸塞州男性老年化研究资料显示,在40~70岁男性当中有超过一半的人受到不同程度ED的困扰,年发病率为124/1000。同时据流行病学研究发现,ED在非高血压... 高血压作为一种最常见的心血管疾病,与勃起功能障碍(ED)有着密切的联系。根据美国马萨诸塞州男性老年化研究资料显示,在40~70岁男性当中有超过一半的人受到不同程度ED的困扰,年发病率为124/1000。同时据流行病学研究发现,ED在非高血压人群中发生率为16%;在高血压人群中,发病率则高达32.1%,远高于正常血压人群。那为什么高血压容易并发ED呢?原因主要有以下3点。 展开更多
关键词 正常血压 流行病学研究 高血压人群 老年化 心血管疾病 美国马萨诸塞州 降压药 ed
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Ethylenediamine tetramethylenephosphonic acid as a selective collector for the improved separation of chalcopyrite against pyrite at low alkalinity
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作者 Jianjun Wang Gaogui Jing +3 位作者 Renji Zheng Zijie Huang Wei Sun Zhiyong Gao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第7期873-882,共10页
Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment a... Chalcopyrite is the main Cu-containing mineral and cannot be separated well from pyrite using traditional xanthate collectors with large amounts of lime depressant, resulting in difficulties of the tailing treatment and associated precious metals recovery. Therefore, in this study, the green and odourless ethylenediamine tetramethylenephosphonic acid(EDTMPA) was introduced as a novel chalcopyrite collector. Flotation results from the binary mineral mixture and real ore demonstrated that EDTMPA could realize the selective separation of chalcopyrite from pyrite relative to ethyl xanthate(EX) without any depressants within the wide p H range of 6.0–11.0, and might replace the traditional high-alkaline lime process. Electrochemical and Fourier transform infrared spectra measurements indicated that the difference in adsorption performance of EDTMPA on chalcopyrite and pyrite was larger than that of EX, suggesting a better selectivity for EDTMPA. Density functional theory calculations demonstrated that there were stronger chemical bonds between P—O groups of EDTMPA and the Fe/Cu atoms on chalcopyrite in the form of a stable six-membered ring. Crystal chemistry calculations further revealed that the activity of metal atoms of chalcopyrite was higher than that of pyrite. Therefore, these basic theoretical results and practical application provide a guidance for the industrial application of EDTMPA in chalcopyrite flotation. 展开更多
关键词 CHALCOPYRITE PYRITE Flotation ethylenediamine tetramethylenephosphonic acid COLLECTOR
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EDS成分分析法在电气熔痕鉴定中的应用
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作者 赵富胜 刘璇 《山东化工》 CAS 2024年第8期167-169,共3页
EDS成分分析法是微量物证鉴定的常用方法,具有灵敏度高、操作简单快速等特点,在纤维、金属、玻璃、油漆及纸张等各类微量物证的鉴定中有着广泛的应用。在火灾痕迹物证鉴定领域,EDS成分分析法已成为重要方法之一。通过探讨三起采用EDS成... EDS成分分析法是微量物证鉴定的常用方法,具有灵敏度高、操作简单快速等特点,在纤维、金属、玻璃、油漆及纸张等各类微量物证的鉴定中有着广泛的应用。在火灾痕迹物证鉴定领域,EDS成分分析法已成为重要方法之一。通过探讨三起采用EDS成分分析法对电气熔痕进行鉴定的实例,提出在火灾现场物证取样、熔痕鉴定和鉴定意见运用等方面的注意事项。 展开更多
关键词 X射线能谱仪 edS成分分析法 电气熔痕鉴定
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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给定控制数的连通图的最大EDS极图
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作者 杨丽英 雷勇 《吕梁学院学报》 2024年第2期8-10,共3页
图G的偏心距离和(EDS)定义为ξ^(d)(G)=∑_(v∈V)ε_(G)(v)D_(G)(v),其中ε_(G)(v)是顶点v的偏心率,D_(G)(v)是顶点v到G中其它所有顶点的距离之和.通过研究图的EDS,给出了Miao等猜想的一个更简单的证明,确定了给定控制数的连通图的最大... 图G的偏心距离和(EDS)定义为ξ^(d)(G)=∑_(v∈V)ε_(G)(v)D_(G)(v),其中ε_(G)(v)是顶点v的偏心率,D_(G)(v)是顶点v到G中其它所有顶点的距离之和.通过研究图的EDS,给出了Miao等猜想的一个更简单的证明,确定了给定控制数的连通图的最大EDS极图. 展开更多
关键词 控制数 连通控制数 edS
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Performance evaluation of laterite soil embankment stabilized with bottom ash,coir fiber,and lime
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作者 Yunusa Hamdanu SANI Amin EISAZADEH 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2334-2351,共18页
In tropical regions,heavy rainfall induces erosion and shallow landslides on road embankments.Cement-based stabilization methods,common in these regions,contribute to climate change due to their high carbon footprint.... In tropical regions,heavy rainfall induces erosion and shallow landslides on road embankments.Cement-based stabilization methods,common in these regions,contribute to climate change due to their high carbon footprint.This study explored the potential application of coir fiber-reinforced laterite soil-bottom ash mixtures as embankment materials in the tropics.The objective is to enhance engineered embankment slopes'erosion resistance and stability while offering reuse options for industrial byproducts.This study examined various mix designs for unconfined compressive strength(UCS)and permeability,utilizing 30%bottom ash(BA)and 1%coir fiber(CF)with varying sizes ranging from 10 to 40 mm,6%lime,and laterite soil(LS),followed by microstructural analyses.The results demonstrate that the compressive strength increases as the CF length increases to 25 mm.In contrast,permeability increases continuously with increasing CF length.Lime-treated mixtures exhibit superior short-and long-term strength and reduce permeability owing to the formation of cementitious materials,as confirmed by microstructural analyses.A lab-scale slope box was constructed to evaluate the surface erosion of the stabilized laterite soil embankment.Based on the rainfall simulation results,the LS-BA-CF mixtures show better resistance to erosion and deformation compared to untreated LS,especially when lime is added to the top layer.This study provides insights into a sustainable and cost-effective approach for slope stabilization using BA and CF,offering a promising solution for tropical regions susceptible to surface erosion and landslides. 展开更多
关键词 Lateritic soil Bottom ash Coir fiber LIME Unconfined compressive strength PERMEABILITY FESEM/edS Rainfall simulation tests
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Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH2/Nafion composite membranes
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作者 Xu Li Dongwei Zhang +7 位作者 Si Chen Yingzhao Geng Yong Liu Libing Qian Xi Chen Jingjing Li Pengfei Fang Chunqing He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1734-1746,共13页
High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH2(PCP-MCN),a kind of hybrid metal-organic framework,which exh... High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH2(PCP-MCN),a kind of hybrid metal-organic framework,which exhibits a superior proton conductivity.PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes.Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated.Significant enhancement in proton conduction for PCP-MCN around 55℃ is interestingly found due to the thermal motion of the PCP molecular chains.Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains,i.e.,the formation of substantial acid–base pairs(-SO_(3)^(-)…^(+)H–NH-),which further improves compatibility between additive and Nafion matrix.At the same humidity and temperature condition,the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion.Proton conductivity(σ)over wide ranges of humidities(30-100%RH at 25℃)and temperatures(30-98℃ at 100%RH)for prepared membranes is measured.The s in PCPMCN/Nafion composite membranes is remarkably enhanced,i.e.0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98℃ and 100%RH,because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation–deprotonation processes.The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN.In particular,when 3 wt.%PCP-MCN was added to Nafion,the power density of a single-cell fabricated with this composite membrane reaches impressively 0.480,1.098 W/cm^(2) under 40%RH,100%RH at 60℃,respectively,guaranteeing it to be a promising proton exchange membrane. 展开更多
关键词 Nafion composite membrane Surface-modified MIL-101-Cr-NH2 Proton conductivity Single-cell performance
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Thermo-Mechanical, Physico-Chemical, Morphological, and Fire Characteristics of Eco-Friendly Particleboard Manufactured with Phosphorylated Lignin Addition
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作者 Apri Heri Iswanto Harisyah Manurung +14 位作者 Asma Sohail Lee Seng Hua Petar Antov Deded Sarip Nawawi Sarah Latifah Dewi Shafa Kayla Sukma Surya Kusumah Muhammad Adly Rahandi Lubis Linda MakovickáOsvaldová MohdHazwan Hussin Rangabhashiyam Selvasembian Lum Wei Chen Puji Rahmawati Nurcahyani Nam Hun Kim Widya Fatriasari 《Journal of Renewable Materials》 EI CAS 2024年第7期1311-1341,共31页
Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics ... Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics of particleboards were compared to that of ultralow emitting formaldehyde(ULEF-UF).Thefillers derived from Eucalyptus spp.kraft-lignin were added forflame retardancy enhancement.10%of each lignin and modified lig-nin was added into the ULEF-UF and citric acid-sucrose bonded particleboards.Analyses applied to particle-boards included thermal characteristics,X-ray diffraction analysis(XRD),morphological properties,Fourier transform infrared spectroscopy(FTIR),as well as physical,mechanical,andfire resistance characteristics of the laboratory-fabricated particleboards.Lignin and modified lignin resulted in improved thermal stability of the composites bonded with ULEF-UF while the improvement in the particleboard bonded with citric acid-sucrose was not significant.The introduction offiller exerted a higher influence on the UF-bonded particleboards compared to composites fabricated with citric acid-sucrose.Generally,the presence of lignin,lignosulfonate,and phosphorylated lignosulfonate enhanced the mechanical strength of the ULEF-bonded particleboards,although their dimensional stability has deteriorated.Markedly,the use of lignin and lignosulfonate enhanced thefire resis-tance of the particleboards produced with lower observed weight loss.All laboratory particleboards exhibited satisfactoryfire resistance,attaining a V-0 rating in according to the UL-94 standard. 展开更多
关键词 Modified lignin eco-friendly particleboard fire and thermal properties citric acid-sucrose ultralow-emitting urea-formaldehyde resin
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SEM-EDS结合结垢趋势模拟软件在反渗透膜污堵原因分析中的应用
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作者 殷明威 吴家琛 马兴峰 《给水排水》 CSCD 北大核心 2024年第3期82-86,共5页
回用水系统中,反渗透膜的污堵问题经常发生。而污堵的原因常常难以确定,进而导致无法从根本上解决污堵问题。详细阐述了先利用SEM-EDS分析反渗透膜微观结构污堵情况和污堵物元素分布,确定污堵物主要成分,再利用结垢趋势模拟软件模拟出... 回用水系统中,反渗透膜的污堵问题经常发生。而污堵的原因常常难以确定,进而导致无法从根本上解决污堵问题。详细阐述了先利用SEM-EDS分析反渗透膜微观结构污堵情况和污堵物元素分布,确定污堵物主要成分,再利用结垢趋势模拟软件模拟出反渗透系统最佳运行条件,从而解决反渗透膜污堵问题的过程和方法。从实际应用案例来看,SEM-EDS结合结垢趋势模拟软件可以快速准确的找到膜系统污堵原因,并从根本上解决污堵问题。 展开更多
关键词 SEM-edS 结垢趋势模拟 反渗透膜 污堵原因
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能量色散X射线荧光光谱法(ED-XRF)测定粗硒中的硒含量
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作者 周明俊 张胜 《广州化工》 CAS 2024年第2期170-172,186,共4页
针对容量法和重量法测定粗硒中硒含量过程中存在的流程长、操作繁琐等问题,本文考察了不同的压样条件,调整压力以及添加不同比例的纤维素、硼酸和碳酸锂等,最终选择采用碳酸锂作为混合剂,将粗硒粉末样品和碳酸锂粉末按照比例1∶1混匀,... 针对容量法和重量法测定粗硒中硒含量过程中存在的流程长、操作繁琐等问题,本文考察了不同的压样条件,调整压力以及添加不同比例的纤维素、硼酸和碳酸锂等,最终选择采用碳酸锂作为混合剂,将粗硒粉末样品和碳酸锂粉末按照比例1∶1混匀,然后在压样机上用10 t压力压制成测试样片,并考察了测试样片的均匀性。在选定的工作条件下,采用能量色散X射线荧光光谱仪(ED-XRF)建立工作曲线,可以实现对粗硒中硒含量的定量测定,同时将测定结果与容量法测定结果进行对比,结果一致。本方法快速准确。 展开更多
关键词 粗硒 碳酸锂 ed-XRF 定量分析
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Pathogenesis and treatment of diabetes mellitus-related erectile dysfunction: current therapies and potential challenges
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作者 Han-Yu He# Fan-Yu Meng +4 位作者 Huan-Tian Cui Jun-Yu Luo Si-Qi Ma Wei-Bo Wen Jie Zhao 《Clinical Research Communications》 2024年第2期11-17,共7页
Erectile dysfunction(ED)is one of the important complications of diabetes,which is very common in diabetic patients,affecting more than half of male patients,and the incidence of the disease is about 3.5 times that of... Erectile dysfunction(ED)is one of the important complications of diabetes,which is very common in diabetic patients,affecting more than half of male patients,and the incidence of the disease is about 3.5 times that of the normal population.The pathogenesis of diabetic erectile dysfunction(DMED)is complex,involving nerve,vascular,endocrine,muscular and psychological aspects.At present,the therapeutic approaches of DMED include drug therapy,surgery,physical therapy and so on.This article provides a review of current research on the pathogenesis and treatment of DMED.Further elucidation of the pathogenesis of DMED and the development of new therapeutic approaches are of great significance for the prevention and treatment of DMED. 展开更多
关键词 diabetes mellitus(DM) erectile dysfunction(ed) PATHOGENESIS THERAPIES
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Determination of Egg Shell Structure and Mineral Composition Using SEM-EDS and Identification the Possibility to Produce Fertilizer
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作者 Purevjav Urjintseren Jargalsaikhan Byambaa 《Journal of Materials Science and Chemical Engineering》 2024年第3期21-30,共10页
Throwing out egg shells without using them depreciates a vital source of calcium. As an egg shell contains twice the amount of calcium a person needs a day, it is considered as the richest source of calcium of natural... Throwing out egg shells without using them depreciates a vital source of calcium. As an egg shell contains twice the amount of calcium a person needs a day, it is considered as the richest source of calcium of natural origin. Egg shells have been traditionally and widely used in medicine, beauty science and food production for decades. In spite of that, there is a lack of new solutions that profoundly study mineral elements and beneficial components contained in egg shells for further usage as a product. Assuming we consume 2 eggs a day, the yearly consumption for a person is 730 eggs. As beneficial component, the egg shell structure and mineral elements, were determined in 3 types of samples (Mongolian eggs, Russian eggs, and iodized eggs) by SEM-EDS (Scanning electron microscopy with energy dispersive spectroscopy), a state-of-the-art research method. Consequently, it was established that egg shells consists of Ca (72.6% - 85.7%), Mg (2.7% - 4.5%), Si (0.3% - 0.6%), P (7.0% - 18.1%), S (0.5% - 2.0%), K (0.4% - 0.9%), I (2.6% - 3.0%), respectively. Additionally, the D3.8 × 120, 250, 500, and 1000 times zoomed images of shell structure (SEM) of each sample were examined, and the results were compared and evaluated. The reverse titration method examination has demonstrated that the calcium carbonate (CaCO<sub>3</sub>) content in egg shells is 91% - 92.5%, and pH is 8.41 - 8.75. Ultimately, fertilizer containing 97.7% Ca without chemical additives has been extracted by grounding the eggshells to 4.4 μm, then preparing the mixture at the rate of 20:0.5 (shell: mix, enriched with mandarin and lemon peel) and adjusting its pH to 7.5 - 8.0. Further research on the impact of fertilizer on growing process of indoor flowers has been commenced. 展开更多
关键词 SEM-edS Analysis Calcium Carbonate Organic Fertilizer
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基于ED-SIFT算法的高分辨率遥感图像快速拼接
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作者 杨云源 陈瑞 《测绘工程》 2023年第1期8-13,共6页
基于特征点检测的高分辨率图像拼接运算量大、速度慢,改进后可以提高效率。从减少参与SIFT计算的数据量和优化算法两方面实现图像拼接加速。建立基于ED-SIFT的图像拼接算法,图像边缘检测优选Soble算子;使用Python+OpenCV,对WorldView3... 基于特征点检测的高分辨率图像拼接运算量大、速度慢,改进后可以提高效率。从减少参与SIFT计算的数据量和优化算法两方面实现图像拼接加速。建立基于ED-SIFT的图像拼接算法,图像边缘检测优选Soble算子;使用Python+OpenCV,对WorldView3切片数据进行拼接实验,平均耗时为0.96 s;与传统基于SIFT的图像拼接算法相比,在保证一定数目的特征点同时,速度加快9.47倍。使用该算法对重叠率为20%、65%、80%的切片数据拼接成功,平均耗时都在0.96~1.08 s。继续用OpenCV+Numba并行运算实现该算法,对运算提速已不明显。基于ED-SIFT的图像拼接算法对高分辨率遥感图像拼接提速明显,对不同重叠率图像拼接皆有效。 展开更多
关键词 高分辨率遥感图像 快速拼接 ed-SIFT 特征点检测 OPENCV
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STUDIES OF THE INITIATION MECHANISM OF VINYL POLYMERIZATION WITH THE SYSTEM PERSULFATE/N-ALKYL SUBSTITUTED ETHYLENEDIAMINE DERIVATIVES 被引量:1
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作者 郭新秋 丘坤元 冯新德 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第2期165-173,共9页
Effects of N-alkyi substituted ethylenediamine derivatives on vinyl polymerization using persulfate as initiator were studied. The apparent kinetic equations and overall activation energies of acrylamide polymerizatio... Effects of N-alkyi substituted ethylenediamine derivatives on vinyl polymerization using persulfate as initiator were studied. The apparent kinetic equations and overall activation energies of acrylamide polymerization were determined using the above mentioned system as initiator. The promoting activities of different diamine derivatives on vinyl polymerization are in the order of tertiary diamine>secondary diamine>primary diamine. Diamines having methyl groups as the substituent on their nitrogen atom possess higher promoting activity than that of having larger alkyl groups. The initial free radicals produced through the redox reaction of persuifate and diamines were studied by spin strapping technique and ESR spectroscopy. The results obtained confirm the fact that the initial free radicals of the diamine species can initiate vinyl polymerization and become the amino end group of the resulting polymers. 展开更多
关键词 PERSULFATE ethylenediamine Derivatives ESR ACRYLAMIDE Radical Polymerization Redox System
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α-Oxoketene Cyclic S, S-cetals Chemistry-Substitution Reaction of α,α'-Dicinnamoyl Ketene Cyclic S, S-Acetals with Ethylenediamine 被引量:2
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作者 Mei Xin ZHAO Qun LIU +4 位作者 Fu Shun LIANG Jing Fu LIU Bao Zhong ZHAO LianZhong LI (Department of Chemistry, Northeast Normal University, Changchun, 130024)(Department of Chemistry, Jilin Teacher college, Jilin, 131000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第3期231-232,共2页
α,α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α'-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yiel... α,α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α,α'-dicinnamoyl ketene cyclic N,N-acetals 5. This process provides a new method for thesynthesis of 5 in high yield under mild conditions. 展开更多
关键词 α α'-dicinnamoyl ketene cyclic S S-acetals ethylenediamine substitution reaction α α'-dicinnamoyl ketene cyclic N N-acetals
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Effect of butanol on flotation separation of quartz from hematite with N-dodecyl ethylenediamine 被引量:7
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作者 Liu Wengang Liu Wenbao +3 位作者 Wang Xinyang Wei Dezhou Zhang Hao Liu Wei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1059-1063,共5页
In order to investigate the effect of butanol on quartz flotation when N-dodecyl ethylenediamine(ND)was used as collector, single mineral flotation and artificial mixed mineral(hematite and quartz were mixed at a mass... In order to investigate the effect of butanol on quartz flotation when N-dodecyl ethylenediamine(ND)was used as collector, single mineral flotation and artificial mixed mineral(hematite and quartz were mixed at a mass ratio of 3:2) separation were conducted in the laboratory. Experimental results indicated that addition of butanol could improve the collecting performance of ND on quartz and enhance the floatability of quartz. Best flotation recovery of quartz was obtained when butanol was mixed with ND at a mass ratio of 1:1. Moreover, the molecular structure of alcohols had a significant effect on mineral recovery. Best separation efficiency could be obtained when tert-butanol was added as it had the largest cross-sectional area. Zeta potential measurements indicated that alcohols could strengthen electrostatic adsorption between quartz and collector. Molecular dynamic simulations revealed that co-adsorption of alcohols along with ND had taken place on the quartz surface, and ND/tert-butyl combinations were more easily absorbed on the quartz surface. 展开更多
关键词 Butanol N-dodecyl ethylenediamine Flotation separation Co-adsorptionQuartz
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Synthesis,Crystal Structure and Antimicrobial Study of N,N,N'-Tris(3-aminopropyl)ethylenediamine Copper(Ⅱ) Diperchlorate 被引量:1
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作者 许兴友 许同桃 +3 位作者 高健 王大奇 陆路德 徐国想 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期121-125,共5页
The title compound [Cu(C11H29N5)](ClO4)2 was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the monoclinic system, space group P21/n with... The title compound [Cu(C11H29N5)](ClO4)2 was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the monoclinic system, space group P21/n with α = 9.405(2), b = 14.495(3), c = 14.715(3) A, β= 90.262(3)°, V=2006.1(7) A^3,M,=493.83,Z=4,F)(000)= 1028,Dc= 1.635 g/cm^3, T= 298(2) K,μ= 1.403 mm^-1 and = 0.71073 A. The was refined to R = 0.0508 and wR = 0. 1250 for 2293 observed reflections with I 〉 2σ(I). The Cu(Ⅱ) atom possesses a five-coordtinate CuN5 environment which shows a slightly distorted square-pyramidal geonetry. Antimicrobial activity study found that the complex is active against Salmonella species, Staphylococcus aureu, Bacillus pumilus and Bacillus coliforms. 展开更多
关键词 N N N'-tris(3-aminopropyl)ethylenediamine copper compound crystal antimicrobial activity
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Crystal Structures of Co(Ⅱ) and Cu(Ⅱ) Complexes and Ammonium Salt Involving Ethylenediamine 被引量:1
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作者 LUO Mei WANG Lei +3 位作者 QIU Jing-Jing ZHANG Jia-Hai LI Qian-Rong YIN Hao 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第12期1835-1840,共6页
The Co(II) complex I and ammonium salt II were synthesized from the direct reaction of 1,2-ethylenediamine and cobaltous acetate tetrahydrate and manganese acetate tetrahydrate in anhydrous ethanol. Treatment of N,N... The Co(II) complex I and ammonium salt II were synthesized from the direct reaction of 1,2-ethylenediamine and cobaltous acetate tetrahydrate and manganese acetate tetrahydrate in anhydrous ethanol. Treatment of N,N'-bis(salicylidene)ethylenediamine with Cu(OAc)2·H2O results in the formation of Cu(II) complex III. C14H37CoNaO8 (I): triclinic, space group P1, a = 8.6296(12), b = 12.0291(17), c = 12.1108(17) A, α = 75.335(2), β = 69.991(2), γ = 72.248(2)°, V= 1109.4(3) A3, Z = 2, ρcaloa = 1.342 g/cm3, the final R= 0.0342 for 4817 observed reflections with I 〉 2σ(I) and Rw = 0.1263 for all data. C6H16N204 (II): space group P1, a = 5.5513(10), b = 5.5589(11), c = 7.4437(14) A, α = 94.332(4), β = 104.497(4), γ = 103.487(4)°,V= 214.06(7) A3, Z = 1, ρcalcd = 1.398 g/cm3, the final R = 0.0431 for 829 observed reflections with I〉 2σ(I) and Rw = 0.1263 for all data. C14H37CuN40 (III), space group P21/n, a = 9.050(9), b = 18.434(17), c = 11.659(11) A, β = 107.134(19)°, V= 1859(3) A3, Z = 4, ρcalcd =1.443 g/cm3, the final R = 0.0616 for 3308 observed reflections (O 〉 2σ(I)) and Rw = 0.1229 for all data. Their structures were all determined by X-ray diffraction, elemental analysis and IR. 展开更多
关键词 Co(II) complex I ammonium salt II 1 2-ethylenediamine cobaltous acetatetetrahydrate manganese acetate tetrahydrate N N'-bis(salicylidene)ethylenediamine Cu(OAc)2·H2O
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Thermodynamics of solubility of Cu_2(OH)_2CO_3 in ammonia-ammonium chloride-ethylenediamine(En)-water system 被引量:2
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作者 刘维 唐谟堂 +3 位作者 唐朝波 何静 杨声海 杨建广 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第2期336-343,共8页
In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.... In order to decrease the evaporating rate of ammonia and increase the solubility of copper in the solution,ethylenediamine was added into the ammonia-ammonium chloride system to leach the copper-containing oxide ores.The thermodynamic model was constructed and the solubility of malachite Cu2(OH)2CO3 in the ammonia-ammonium chloride-ethylenediamine(En)-water system was calculated using the exponential computation method based on both mass balance and charge balance.It is found that the solubility of copper can be increased and the free ammonia concentration can be decreased by submitting partial ammonia with ethylenediamine.The lower free ammonia concentration in the solution is a guarantee to the lower evaporating rate of ammonia.The conditions of malachite Cu2(OH)2CO3 converting to atacamite Cu(OH)1.5Cl0.5 were also studied.A group of experiments were designed to validate the veracity of the results of the thermodynamic calculation.It is found that the thermodynamic model is reliable and it can guide the leaching process. 展开更多
关键词 thermodynamics solubility malachite ammonia ammonium chloride ethylenediamine(En)
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Application of EDTMPS as a novel calcite depressant in scheelite flotation 被引量:6
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作者 Fen Jiao Wei Li +4 位作者 Xu Wang Congren Yang Zhengquan Zhang Liwen Fu Wenqing Qin 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期639-647,共9页
In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mech... In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mechanism was revealed by contact angle measurement, FTIR analysis, Zeta potential test and XPS analysis. The flotation experiment results showed that scheelite and calcite could be efficiently separated under the following conditions: pulp p H=9.5, Na OL concentration of 1.5×10^(-4)mol/L, EDTMPS concentration of 3.0×10^(-5)mol/L, a scheelite concentrate with WO3grade of 65.49%, recovery of 83.29%and separation efficiency of 65.29% could be obtained from the artificially mixed minerals. The analysis results of mineral surface properties demonstrated that EDTMPS was strongly adsorbed onto the calcite surface through the reaction between the phosphonate group and the calcium ions, which hindered Na OL adsorption and increased the hydrophilicity of calcite. However, EDTMPS had weak adsorption strength on the scheelite surface, which didn’t affect further adsorption of Na OL, hence, the scheelite remained hydrophobic. Consequently, the selective adsorption of EDTMPS on the two minerals’ surfaces increased a difference in wettability and thus enabling them to be separated by flotation. Finally, the mechanism model of this flotation separation process was established. 展开更多
关键词 ethylenediamine tetramethylene phosphonic sodium SCHEELITE CALCITE FLOTATION Selective depression
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