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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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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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Waste acid recovery utilizing monovalent cation permselective membranes through selective electrodialysis
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作者 Yanran Zhu Yue Zhou +4 位作者 Qian Chen Rongqiang Fu Zhaoming Liu Liang Ge Tongwen Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期45-57,共13页
Selective electrodialysis(SED)has surfaced as a highly promising membrane separation technique in the realm of acid recovery owing to its ability to effectively separate monovalent ions through the utilization of a po... Selective electrodialysis(SED)has surfaced as a highly promising membrane separation technique in the realm of acid recovery owing to its ability to effectively separate monovalent ions through the utilization of a potential difference.However,the current SED process is limited by conventional commercial monovalent cation permselective membranes(MCPMs).This study systematically investigates the use of an independently developed MCPM in the SED process for acid recovery.Various factors such as current density,volume ratio,initial ion concentration,and waste acid systems are considered.The independently developed MCPM offers several advantages over the commercial monovalent selective cation-exchange membrane(CIMS),including higher recovered acid concentration,better ion flux ratio,improved acid recovery efficiency,increased recovered acid purity,and higher current efficiency.The SED process with the MCPM achieves a recovered acid of 95.9%and a concentration of 2.3 mol·L^(–1) in the HCl/FeCl_(2) system,when a current density of 20 mA·cm^(-2) and a volume ratio of 1:2 are applied.Similarly,in the H_(2)SO_(4)/FeSO_(4) system,a purity of over 99%and a concentration of 2.1 mol·L^(–1) can be achieved in the recovered acid.This study thoroughly examines the impact of operation conditions on acid recovery performance in the SED process.The independently developed MCPM demonstrates outstanding acid recovery performance,highlighting its potential for future commercial utilization. 展开更多
关键词 Selective electrodialysis WASTEWATER Monovalent cation permselective membranes SEPARATION RECOVERY
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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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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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Acid precipitation coupled electrodialysis to improve separation of chloride and organics in pulping crystallization mother liquor 被引量:1
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作者 Zhaoyang Li Rongzong Li +3 位作者 Zhaoxiang Zhong Ming Zhou Min Chen Weihong Xing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第12期2917-2924,共8页
Inefficient separation of inorganic salts and organic matters in crystallization mother liquor is still a problem to industrial wa stewater treatment since the high salinity significantly impedes organic pollutant deg... Inefficient separation of inorganic salts and organic matters in crystallization mother liquor is still a problem to industrial wa stewater treatment since the high salinity significantly impedes organic pollutant degradation by oxidation or incineration.In the study,acidification combined electrodialysis(ED)was attempted to effectively separate Cl-ions from organics in concentrate pulping wastewater.Membrane’s rejection rate to total organic carbon(TOC)was 85%at wastewater intrinsic pH=9.8 and enhanced to 93%by acidifying it to pH=2 in ED process.Negative-charged alkaline organic compounds(mainly lignin)could be liberated from their sodium salt forms and coagulated in acidification pretreatment.Neutralization of the organic substances also made their electro-migration less effective under electric driving force and in particular improved separation efficiency of chloride and organics.After acid-ED coupled treatment(pH=2 and J=40 mA·cm-2)[TOC]remarkably reduced from 1.315 g·L-1 to 0.048 g·L-1 and[Cl-]accumulated to 130 g·L-1 in concentrate solution.Recovery rate of NaCl was 89%and the power consumption was 0.38 kW·h·kg-1 NaCl.Irreversible fouling was not caused as electric resistance of membrane pile maintained stably.In conclusion,acidic-ED is a practical option to treat salinity organic wastewater when current techniques including thermal evaporation and pressure-driven membrane se paration present limitations. 展开更多
关键词 CRYSTALLIZATION mother LIQUOR Acid precipitation electrodialysis CHLORIDE recovery
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Removal of Mercury(Hg(Ⅱ)) from Seaweed Extracts by Electrodialysis and Process Optimization Using Response Surface Methodology
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作者 SUN Jiuyi SU Xin +5 位作者 LIU Zhen LIU Junlan MA Zhun SUN Yongchao GAO Xueli GAO Jun 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第1期135-142,共8页
In this work,response surface methodology(RSM)was employed to model and optimize electrodialysis process for mercury(Hg(II))removal from seaweed extracts.Box-Behnken design(BBD)was utilized to evaluate the effects and... In this work,response surface methodology(RSM)was employed to model and optimize electrodialysis process for mercury(Hg(II))removal from seaweed extracts.Box-Behnken design(BBD)was utilized to evaluate the effects and the interaction of influential variables such as operating voltage,influent flow rate,initial concentration of Hg(II)on the removal rate of Hg(II).The developed regression model for removal rate response was validated by analysis of variance,and presented a good agreement of the experimental data with the quadratic equation with high value coefficient of determination value(R2=0.9913,RAdj 2=0.9678).The optimum operating parameters were determined as 7.17V operating voltage,72.54L h−1 influent flow rate and 5.04mgL−1 initial concentration of mercury.Hg(II)removal rate of 76.45%was acquired under the optimum conditions,which showed good agreement with model-predicted(75.81%)result.The results revealed that electrodialysis can be considered as a promising strategy for removal of Hg(II)from seaweed extracts. 展开更多
关键词 electrodialysis seaweed extracts mercury removal response surface methodology Box-Behnken design
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Concentration of mixed acid by electrodialysis for the intensification of absorption process in acrylic acid production
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作者 Hanxiao Du Lixin Xie +1 位作者 Jie Liu Shichang Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期10-18,共9页
The absorption process in acrylic acid production was water-intensive.The concentration of acrylic acid before distillation process was low,which induced to large amount of wastewater and enormous energy consumption.I... The absorption process in acrylic acid production was water-intensive.The concentration of acrylic acid before distillation process was low,which induced to large amount of wastewater and enormous energy consumption.In this work,a new method was proposed to concentrate the side stream of absorption column and thus increase the concentration in bottom product by electrodialysis.The influence of operating conditions on concentration rate and specific energy consumption were investigated by a laboratory-scale device.When the voltage drop was 1 V·cP^(-1)(1 cP=10^(-3) Pa·s),flow velocity was 3 cm·s^(-1) and the temperature was 35℃,the concentration rates of acrylic acid and acetic acid could be 203.3%and 156.6%in the continual-ED process.Based on the experimental data,the absorption process combined with ED was simulated,in which the diluted solution from ED process was used as spray water and the concentrated solution was feed back to the absorption column.The results shown that the flow rate of spray water was decreased by 37.1%,and the acrylic acid concentration at the bottom of the tower was increased by 4.56%.The ions exchange membranes before and after use 1200 h were tested by membrane surface morphology(scanning electron microscope),membrane chemical groups(infrared spectra),ion exchange capacity,and membrane area resistance,which indicated the membrane were stable in the acid system.This method provides new method for energy conservation and emission reduction in the traditional chemical industry. 展开更多
关键词 Acrylic acid production electrodialysis CONCENTRATION Membranes ABSORPTION Mixtures
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The effect of slow shot speed and casting pressure on the 3D microstructure of high pressure die casting AE44 magnesium alloy 被引量:2
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作者 Chaosheng Ma Wenbo YU +3 位作者 Tongtong Zhang Zihua Zhang Yihu Ma Shoumei Xiong 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第2期753-761,共9页
3D reconstruction and 2D observation were conducted to characterize the microstructure of the castings produced through high pressure die casting with different parameters.Our results indicate that shrinkage pores gen... 3D reconstruction and 2D observation were conducted to characterize the microstructure of the castings produced through high pressure die casting with different parameters.Our results indicate that shrinkage pores generally co-existed with externally solidified crystals(ESCs).In specimen produced without fast slow shot speed,big net-shrinkage pores accompanied with ESCs were found in the center of the specimen.When the casting pressurization was introduced,the shrinkage pores gathered to the specimen center and became much less due to the optimization of melt feeding.Much more porosity was found near the gate rather than in the middle of the rod bar,especially gas pores.Thefilling process simulation reveals that the middle position of the bars wasfirstlyfilled and followed by the near gate position accompanied with one intense turbulentflow. 展开更多
关键词 HPDC parameters Externally solidified crystals(ESCs) POROSITY 3D reconstruction.
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甲苯磺酸瑞马唑仑全身麻醉诱导ED50及ED95的测定 被引量:2
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作者 赵和平 赵刚 +2 位作者 陈燕 严章君 蔡栋江 《浙江临床医学》 2023年第2期196-198,共3页
目的 观察不同剂量甲苯磺酸瑞马唑仑对喉罩插管全身麻醉诱导期患者镇静效能及起效时间的变化,确定其诱导的药物ED50及ED95值.方法 选择全身麻醉手术的可喉罩插管全身麻醉的患者27例,采用改良序贯(Dixon)法测定甲苯磺酸瑞马唑仑用药效果... 目的 观察不同剂量甲苯磺酸瑞马唑仑对喉罩插管全身麻醉诱导期患者镇静效能及起效时间的变化,确定其诱导的药物ED50及ED95值.方法 选择全身麻醉手术的可喉罩插管全身麻醉的患者27例,采用改良序贯(Dixon)法测定甲苯磺酸瑞马唑仑用药效果.设定起始诱导剂量为0.1mg/kg,下一例患者的剂量根据上一例患者诱导出现的结果而定,阴性反应标准,患者诱导后改良警觉/镇静评分(MOAA/S评分)≤1分,BIS≤60时间均<1min.如患者出现阴性反应,下一例患者的诱导剂量下降一个浓度梯度,浓度梯度差值为0.025mg/kg,直至患者出现阳性反应.以此类推,出现6次阴性与阳性交叉后终止研究.结果 甲苯磺酸瑞马唑仑ED50为0.168mg/kg(95%CI:0.137~0.216),ED95为0.297mg/kg(95%CI:0.226~0.828),全身麻醉诱导成功的12例患者中SBP、MAP、DBP呈下降趋势,麻醉诱导前5min(T0)高于其他各时点,在诱导后3min血压降至低点,差异有统计学意义(P<0.05),但血压下降程度均≤30%.诱导后MOAA/S评分≤1分时间为(33.08±9.18)s,BIS≤60时间为(37.42±10.97)s,BIS在1min内降至最低值,随后上升,但插管期间均BIS<60.HR随时间推移呈上升趋势,在用药后2min升至高点,与T0比较,差异有统计学意义(P<0.05).结论 甲苯磺酸瑞马唑仑ED50为0.168mg/kg、ED95为0.297mg/kg,可以安全应用于麻醉诱导期,达到类似丙泊酚起效时间,对循环、心率影响小,能提供足够的镇静时间,减少副作用. 展开更多
关键词 甲苯磺酸瑞马唑仑 全身麻醉诱导 量效关系 ed50 ed95
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Performance comparison of lithium fractionation from magnesium via continuous selective nanofiltration/electrodialysis
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作者 Yong Xu Qingbai Chen +3 位作者 Yang Gao Jianyou Wang Huiqing Fan Fei Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期42-50,共9页
Although selective nanofiltration(SNF)and selective electrodialysis(SED)have been widely adopted in the field of Mg^(2+)/Li^(+)separation,their differences have not been illustrated systematically.In this study,for th... Although selective nanofiltration(SNF)and selective electrodialysis(SED)have been widely adopted in the field of Mg^(2+)/Li^(+)separation,their differences have not been illustrated systematically.In this study,for the first time,SNF and SED processes in continuous mode were studied for Li+fractionation from the same brine with high Mg/Li ratios and their differences were discussed in detail.For a fair analysis of the two processes,typical factors were optimized.Specifically,the optimal operating pressure and feed flow rate for SNF were 2.4 MPa and 140 L·h^(-1),respectively,while the optimal cell-pair voltage and replenishment flow rate for SED were 1.0 V and 14 L·h^(-1),respectively.Although the Li^(+)fractionation capacity of the two processes were similar,the selectivity coefficient of SNF was 24.7% higher than that of SED and,thus,the Mg/Li ratio in purified stream of the former was 19.0% lower than that of the latter.Due to higher ion driving force,SED had clear advantages in recovery ratio and concentration effects.Meanwhile,the specific energy consumption of SED was 20.1% lower than that of SNF.This study provided a better understanding and guidance for the application and improvement of the two technologies. 展开更多
关键词 High Mg/Li brine PURIFICATION Membrane NANOFILTRATION electrodialysis Lithium recovery
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EDS指数与平衡二部图的哈密尔顿性
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作者 李青 刘莉 袁慧 《长春师范大学学报》 2023年第6期6-10,46,共6页
如果一个图的顶点集可以划分为两个不相交的子集X和Y,这里|X|=|Y|,使得每条边都有一个端点在X中,另一个端点在Y中,那么称此图为平衡二部图.本文利用平衡二部图的特殊结构找到了原图或其拟补图关于EDS指数的界,结合平衡二部图中特殊性质... 如果一个图的顶点集可以划分为两个不相交的子集X和Y,这里|X|=|Y|,使得每条边都有一个端点在X中,另一个端点在Y中,那么称此图为平衡二部图.本文利用平衡二部图的特殊结构找到了原图或其拟补图关于EDS指数的界,结合平衡二部图中特殊性质的度序列与边条件,根据原图或其拟补图的EDS指数分别给出一个平衡二部图是可迹的、哈密尔顿或弱哈密尔顿-连通的充分条件. 展开更多
关键词 平衡二部图 拟补图 哈密尔顿性 edS指数
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Accuracy and Precision of Energy Dispersive X-Ray Fluorescence (EDXRF) Analysis of Trace and Major Elements in Rock Standard Reference Materials Using Fine Powder 被引量:1
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作者 Jean Faustin Sabouang Jean Félix Beyala Ateba +4 位作者 Cebastien Joel Guembou Shouop Josue Maya Cedric Tayou Kamkumo Lawan Loubou Mohamadou Augustin Simo 《Journal of Geoscience and Environment Protection》 2023年第6期83-95,共13页
In this work the performance of a screening analytical method for Energy Dispersive X-Ray Fluorescence (EDXRF) analysis in terms of accuracy and precision was evaluated through analysis of rock standard reference mate... In this work the performance of a screening analytical method for Energy Dispersive X-Ray Fluorescence (EDXRF) analysis in terms of accuracy and precision was evaluated through analysis of rock standard reference materials. The method allowed the division of elements into four groups taking into account the excitation energies and measurement conditions of the sample. Two standard reference materials were used and 15 sample replicates were prepared and analyzed, then statistics were applied to assess the precision and accuracy of analytical results. The obtained results show that major compounds or elements (SiO<sub>2</sub>, P<sub>2</sub>O<sub>5</sub>, K<sub>2</sub>O, CaO, Fe<sub>2</sub>O<sub>3</sub>, Ti) can be determined in fine powder sample with a deviation lower than 15%, and a relative standard deviation in the range (1 - 10)%. The deviation was found to be lower than 5% for major compounds such as K<sub>2</sub>O, and CaO, which suggest that the EDXRF is accurate in evaluating major elemental concentrations in rock samples. It was also found that the method seems to be more accurate and precise for major elements than for trace element investigation. This screening analytical method can be used for routine analysis with acceptable results, even though the method should be optimized to increase its precision and accuracy. 展开更多
关键词 ed-XRF Screening Method Rock Material ACCURACY PRECISION
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