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Comparing different domains of analysis for the characterisation of N-glycans on monoclonal antibodies 预览
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作者 Sara Carillo Raquel Peerez-Robles +5 位作者 Craig Jakes Meire Ribeiro da Silva Silvia Millan Martín Amy Farrell Natalia Navas Jonathan Bones 《药物分析学报:英文版》 CAS CSCD 2020年第1期23-34,共12页
With the size of the biopharmaceutical market exponentially increasing,there is an aligned growth in the importance of data-rich analyses,not only to assess drug product safety but also to assist drug development driv... With the size of the biopharmaceutical market exponentially increasing,there is an aligned growth in the importance of data-rich analyses,not only to assess drug product safety but also to assist drug development driven by the deeper understanding of structure/function relationships.In monoclonal antibodies,many functions are regulated by N-glycans present in the constant region of the heavy chains and their mechanisms of action are not completely known.The importance of their function focuses analytical research efforts on the development of robust,accurate and fast methods to support drug development and quality control.Released N-glycan analysis is considered as the gold standard for glycosylation characterisation;however,it is not the only method for quantitative analysis of glycoform heterogeneity.In this study,ten different analytical workflows for N-glycan analysis were compared using four monoclonal antibodies.While observing good comparability between the quantitative results generated,it was possible to appreciate the advantages and disadvantages of each technique and to summarise all the observations to guide the choice of the most appropriate analytical workflow according to application and the desired depth of data generated. 展开更多
关键词 N-GLYCANS BIOPHARMACEUTICALS Monoclonal antibodies Intact mass analysis Mass spectrometry Native mass spectrometry Glycan analysis Peptide mapping Glycopeptide analysis
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Combination of sensitivity and uncertainty analyses for sediment transport modeling in sewer pipes 预览
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作者 Isa Ebtehaj Hossein Bonakdari +7 位作者 Mir Jafar Sadegh Safari Bahram Gharabaghi Amir Hossein Zaji Hossien Riahi Madavar Zohreh Sheikh Khozani Mohammad Sadegh Es-haghi Aydin Shishegaran Ali Danandeh Mehr 《国际泥沙研究:英文版》 SCIE 2020年第2期157-170,共14页
Mitigation of sediment deposition in lined open channels is an essential issue in hydraulic engineering practice.Hence,the limiting velocity should be determined to keep the channel bottom clean from sediment deposits... Mitigation of sediment deposition in lined open channels is an essential issue in hydraulic engineering practice.Hence,the limiting velocity should be determined to keep the channel bottom clean from sediment deposits.Recently,sediment transport modeling using various artificial intelligence(AI)techniques has attracted the interest of many researchers.The current integrated study highlights unique insight for modeling of sediment transport in sewer and urban drainage systems.A novel methodology based on the combination of sensitivity and uncertainty analyses with a machine learning technique is proposed as a tool for selection of the best input combination for modeling process at non-deposition conditions of sediment transport.Utilizing one to seven dimensionless parameters,127 models are developed in the current study.In order to evaluate the different parameter combinations and select the training and testing data,four strategies are considered.Considering the densimetric Froude number(Fr)as the dependent parameter,a model with independent parameters of volumetric sediment concentration(CV)and relative particle size(d/R)gave the best results with a mean absolute relative error(MARE)of 0.1 and a root means square error(RMSE)of 0.67.Uncertainty analysis is applied with a machine learning technique to investigate the credibility of the proposed methods.The percentage of the observed sample data bracketed by 95%predicted uncertainty bound(95PPU)is computed to assess the uncertainty of the best models. 展开更多
关键词 Non-deposition Sediment transport Sensitivity analysis SEWER Uncertainty analysis Urban drainage
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Evaluation of Temporal Changes in Deep Well Water Quality in Igabi Local Government Area of Kaduna State 预览
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作者 John Jiya Musa Otuaro Ebierni Akpoebidimiyen +2 位作者 Mohammed Tanimu Musa Pius Olusegun Olufemi Dada Elijah Tsado Musa 《环境保护(英文)》 2020年第1期22-33,共12页
The research work was carried out in Igabi Local Government of Kaduna State. Thirty water samples from boreholes were randomly collected within the major towns in November to April (Dry), and May to October (Rainy sea... The research work was carried out in Igabi Local Government of Kaduna State. Thirty water samples from boreholes were randomly collected within the major towns in November to April (Dry), and May to October (Rainy season). The samples were analyzed for physical, chemical, and bacteriological parameters and to observe any changes in the groundwater quality of the area. Analysis of variance (ANOVA), Pearson Correlation were performed on the data obtained using SPSS 10.0 for a window for significant variations and inter-element relationship. High mean turbidity was recorded in boreholes in Danfili (12.2 NTU), Kwarau (6.2 NTU). Mean turbidity of 4.3 NTU was recorded in Dry season for wells with Rigachikun having 5.1 NTU. It was observed that a negative correlation exists between well depth and heavy metal concentration. There was also a linear relationship of 0.686 between well distance and nitrate (faecal contaminant). Mean value for Fluoride (0.22 mg/l), Sodium (20.78 mg/l), Calcium (15.7 mg/l), Iron (0.013 mg/l), Nitrate (3.69 mg/l), Cadmium (0.00102 mg/l) Chloride (22.107 mg/l) recorded for sampled wells were all within WHO standard. A high value of 24 mg/l and 25 mg/l for Nitrate was recorded in Saminaka Road and Danfili. An indication of contamination during the rainy season indicates surface-groundwater intrusion (influx). The results of the bacteriological analysis indicated that most wells sampled have a range of 1 cfu/100 ml to 7 cfu/100 ml with Danfili Mani having the highest value (7 cfu/100 ml) which make it unsaved (not Potable). 展开更多
关键词 TEMPORAL CHANGE Analysis GROUNDWATER Physiochemical Bacteriological Quality
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Understanding roof deformation mechanics and parametric sensitivities of coal mine entries using the discrete element method 预览
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作者 Rami Abousleiman Gabriel Walton Sankhaneel Sinha 《矿业科学技术学报:英文版》 CSCD 2020年第1期123-129,共7页
Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and operations.Previous studies have identified that disc... Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and operations.Previous studies have identified that discontinuous,layered roof materials have some self-supporting capacity.This research is a preliminary step towards understanding these mechanics in coal-measure rocks.Although others have considered broad conceptual models and simplified analogs for mine roof behavior,this study presents a unique numerical model that more completely represents in-situ roof conditions.The discrete element method(DEM)is utilized to conduct a parametric analysis considering a range of in-situ stress ratios,material properties,and joint networks to determine the parameters controlling the stability of single-entries modeled in two-dimensions.Model results are compared to empirical observations of roof-support effectiveness(ARBS)in the context of the coal mine roof rating(CMRR)system.Results such as immediate roof displacement,overall stability,and statistical relationships between model parameters and outcomes are presented herein.Potential practical applications of this line of research include:(1)roof-support optimization for a range of coal-measure rocks,(2)establishment of a relationship between roof stability and pillar stress,and(3)determination of which parameters are most critical to roof stability and therefore require concentrated evaluation. 展开更多
关键词 Numerical modeling Discrete element method Coal mine roof rating Analysis of roof bolt systems Sensitivity analysis Strain softening ubiquitous joints Discrete fracture network
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Estimation of drift limits for different seismic damage states of RC frame staging in elevated water tanks using Park and Ang damage index 预览
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作者 Suraj O.Lakhade Ratnesh Kumar O.R.Jaiswal 《地震工程与工程振动:英文版》 SCIE EI CSCD 2020年第1期161-177,共17页
Damage to elevated water tanks in past earthquakes can be attributed to the poor performance of their supporting frame staging. In order to ascertain the performance of these elevated water tanks, it is crucial to cat... Damage to elevated water tanks in past earthquakes can be attributed to the poor performance of their supporting frame staging. In order to ascertain the performance of these elevated water tanks, it is crucial to categorize the damage in quantifiable damage states. Among various parameters to quantify the damage states, the top drift of frame staging can be conveniently correlated to the different damage levels. In literature, drift limits corresponding to different damage states of the frame staging of the elevated water tank are not available. In the present study, drift limits for RC frame staging in elevated water tanks corresponding to different seismic damage states have been proposed. Various damage states of the elevated water tank have been determined using the Park and Ang damage index. The Park and Ang damage index utilizes results of both pushover analysis and incremental dynamic analysis. Twelve models of elevated water tanks have been developed considering variation in staging height and tank capacity. Incremental dynamic analysis has been performed using the suite of twelve actual earthquake ground motions. Based on the regression analysis between damage indexes and drift, limiting drift values for each damage state are proposed. 展开更多
关键词 ELEVATED water tank frame STAGING damage states DRIFT limit 3D modelling INCREMENTAL dynamic ANALYSIS PUSHOVER ANALYSIS
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Seismic and stress qualification of LMFR fuel rod and simple method for the determination of LBE added mass effect 预览
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作者 M.Khizer Jian-Wei Chen +3 位作者 Guo-Wei Yang Qing-Sheng Wu Yong Song Yong Zhang 《核技术:英文版》 SCIE CAS CSCD 2020年第1期42-56,共15页
In this study, two different designs of liquid metal fast reactor(LMFR) fuel rods wire-wrapped and nonwire-wrapped(bare) are compared with respect to different parameters as a means of considering the optimum fuel des... In this study, two different designs of liquid metal fast reactor(LMFR) fuel rods wire-wrapped and nonwire-wrapped(bare) are compared with respect to different parameters as a means of considering the optimum fuel design. Nuclear seismic rules require that systems and components that are important for safety must be capable of bearing earthquake effects, and that their integrity and functionality should be guaranteed. Mode shapes, natural frequencies, stresses on cladding, and seismic aspects are considered for comparison using ANSYS. Modal analysis is compared in a vacuum and in lead–bismuth eutectic(LBE) using potential flow theory by considering the added mass effect. A simple and accurate approach is suggested for the determination of the LBE added mass effect and is verified by a manually calculated added mass, which further proved the usefulness of potential flow theory for the accurate estimation of the added mass effect. The verification of the hydrodynamic function(τ) over the entire frequency range further validated the finite element method(FEM) modal analysis results. Stresses obtained for fuel rods against different loading combinations revealed that they were within the allowable limits with maximum stress ratios of 0.25(bare) and 0.74(wire-wrapped). In order to verify the structural integrity of cladding tubes, stresses along the cladding length were determined during different transients and were also calculated manually for static pressure. The manual calculations could be roughly compared with the ANSYS results, and the two showed a close agreement. Contact analysis methodology was selected,and the most appropriate analysis options were suggested for establishing contact between the wire and cladding for the wire-wrapped design grid independence analysis,which proved the accuracy of the results, confirmed the selection of the appropriate procedure, and validated the use of the ANSYS mechanical APDL code for LMFR fuel rod analysis. The results provided detailed insight into the structural desi 展开更多
关键词 LMFR FUEL ROD Added mass SEISMIC ANALYSIS Contact ANALYSIS
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Single-nucleotide polymorphism screening and RNA sequencing of key messenger RNAs associated with neonatal hypoxic-ischemia brain damage 预览
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作者 Liu-Lin Xiong Lu-Lu Xue +7 位作者 Mohammed Al-Hawwas Jin Huang Rui-Ze Niu Ya-Xin Tan Yang Xu Ying-Ying Su Jia Liu Ting-Hua Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第1期86-95,共10页
A single-nucleotide polymorphism(SNP)is an alteration in one nucleotide in a certain position within a genome.SNPs are associated with disease susceptibility.However,the influences of SNPs on the pathogenesis of neona... A single-nucleotide polymorphism(SNP)is an alteration in one nucleotide in a certain position within a genome.SNPs are associated with disease susceptibility.However,the influences of SNPs on the pathogenesis of neonatal hypoxic-ischemic brain damage remain elusive.Seven-day-old rats were used to establish a hypoxic ischemic encephalopathy model.SNPs and expression profiles of mRNAs were analyzed in hypoxic ischemic encephalopathy model rats using RNA sequencing.Genes exhibiting SNPs associated with hypoxic ischemic encephalopathy were identified and studied by gene ontology and pathway analysis to identify their possible involvement in the disease mechanism.We identified 89 up-regulated genes containing SNPs that were mainly located on chromosome 1 and 2.Gene ontology analysis indicated that the up-regulated genes containing SNPs are mainly involved in angiogenesis,wound healing and glutamatergic synapse and biological processing of calcium-activated chloride channels.Signaling pathway analysis indicated that the differentially expressed genes play a role in glutamatergic synapses,long-term depression and oxytocin signaling.Moreover,intersection analysis of high throughput screening following PubMed retrieval and RNA sequencing for SNPs showed that CSRNP1,DUSP5 and LRRC25 were most relevant to hypoxic ischemic encephalopathy.Significant up-regulation of genes was confirmed by quantitative real-time polymerase chain reaction analysis of oxygen-glucose-deprived human fetal cortical neurons.Our results indicate that CSRNP1,DUSP5 and LRRC25,containing SNPs,may be involved in the pathogenesis of hypoxic ischemic encephalopathy.These findings indicate a novel direction for further hypoxic ischemic encephalopathy research.This animal study was approved on February 5,2017 by the Animal Care and Use Committee of Kunming Medical University,Yunnan Province,China(approval No.kmmu2019038).Cerebral tissue collection from a human fetus was approved on September 30,2015 by the Ethics Committee of Kunming Medical University,Chin 展开更多
关键词 CSRNP1 DUSP5 gene ontology ANALYSIS human FETAL CORTICAL neurons LRRC25 mRNA NEONATAL HYPOXIC ischemic ENCEPHALOPATHY pathogenesis signaling pathway ANALYSIS
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基于超网络的科技论文关键词关联分析 预览
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作者 吴蕾 梁晓贺 宋红燕 《情报学报》 CSSCI CSCD 北大核心 2020年第3期253-258,共6页
科技论文关键词呈现多类型、多关联关系的属性,可以借助具有多层次、多超边的超网络进行表示建模。本研究构建了由研究对象-实验品种-研究用途-技术方法 4层关键词子网和多种关联超边组成的超网络模型,并将该超网络模型用于"农业... 科技论文关键词呈现多类型、多关联关系的属性,可以借助具有多层次、多超边的超网络进行表示建模。本研究构建了由研究对象-实验品种-研究用途-技术方法 4层关键词子网和多种关联超边组成的超网络模型,并将该超网络模型用于"农业动物生殖细胞和干细胞调控"领域的科技论文的实证分析。该超网络模型在揭示单层关键词子网同质关联关系的同时,也能挖掘多层子网之间的隐性异质关联关系,从而发现了该领域常用技术方法、实验品种、研究对象和研究用途,同时还发现了该领域的技术空白点和技术应用空白点,这些空白点很可能成为未来的研究热点。 展开更多
关键词 分析 关联分析 超网络 科技论文
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Parameter study of sinter waste heat recovery in vertical tank based on energy and exergy analysis
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作者 Jun-sheng Feng Sheng Zhang +1 位作者 Hui Dong Gang Pei 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2020年第1期22-32,共11页
The parameter study of sinter waste heat recovery in vertical tank was conducted numerically by using energy and exergy analysis,and the experimental data obtained from a homemade experimental apparatus was applied to... The parameter study of sinter waste heat recovery in vertical tank was conducted numerically by using energy and exergy analysis,and the experimental data obtained from a homemade experimental apparatus was applied to verify the reliability of numerical model.Based on the first and second laws of thermodynamics,the effects of flow rate of cooling air(FRCA)and inlet temperature of cooling air(ITCA),as well as the inner diameter of cooling section(IDCS)and height of cooling section(HCS),on the sinter cooling process were analyzed in detail.The results show that the average deviation between the experimental data and calculation values is 4.93%,and the model reliability is verified.The enthalpy exergy of outlet air tends to increase first and then decrease with increasing the FRCA and ITCA,while increasing the IDCS only leads to the increase in enthalpy exergy of outlet air.For a given operational condition,the enthalpy exergy of outlet air can reach a maximum value with increasing the HCS.The vertical tank could obtain the maximum enthalpy exergy of outlet air through the adjustments of FRCA and ITCA,as well as the HCS. 展开更多
关键词 SINTER Waste heat recovery Porous medium-Energy analysis Exergy analysis Vertical bank
Effects of Tidal Channels and Roads on Landscape Dynamic Distribution in the Yellow River Delta,China 预览
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作者 YU Xiaojuan ZHANG Zhongsheng +2 位作者 XUE Zhenshan WU Haitao ZHANG Hongri 《中国地理科学:英文版》 SCIE CSCD 2020年第1期170-179,共10页
Landscape characters in estuarine regions generally controlled by tidal regimes and human activities like road construction.In this work,tidal channels and road construction in the Yellow River Delta(YRD)were extracte... Landscape characters in estuarine regions generally controlled by tidal regimes and human activities like road construction.In this work,tidal channels and road construction in the Yellow River Delta(YRD)were extracted by visual interpretation methods so as to decipher impacts of tidal channel development and road construction on landscape patch change during 1989–2016.Spatial distribution history of three wetlands,which covered by Phragmites australis(freshwater marsh,FM),Suaeda salsa(salt marsh,SM),and mudflats(MD)were also established.Results indicated that tidal channel,number,frequency,and fractal dimension were all the maximum in 2003,and the minimum in 1998,respectively.Road length,number,and density showed increasing trend during 1989–2016.MD were the predominant landscape type,followed by FM and SM during 1989-2016.Principal component analysis implied two extracted factors,F1 and F2,which could represent 91.93% of the total variations.F1 mainly proxied tidal channel development,while F2 represented road construction.A multiple linear regression analysis showed positive effects of both F1 and F2 on FM patch numbers and negative impacts on SM patch areaes with R^2 values of 0.416 and 0.599,respectively.Tidal channels were negatively related to MD patch numbers,while roads were positively related to that.In any case,road construction showed larger impacts on landscape type shifting than that of tidal channel development in the YRD. 展开更多
关键词 TIDAL channel development road construction principal component ANALYSIS multiple linear regression ANALYSIS the YELLOW River DELTA
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The role of viscoelastic damping on retrofitting seismic performance of asymmetric reinforced concrete structures 预览
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作者 Zeshan Alam Chunwei Zhang Bijan Samali 《地震工程与工程振动:英文版》 SCIE EI CSCD 2020年第1期223-237,共15页
The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance ... The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance because such structures create abrupt changes in the stiffness or strength that may lead to undesirable stress concentrations at weak locations. Structural control devices are one of the effective ways to reduce seismic impacts, particularly in asymmetric structures. For passive vibration control of structures, VE dampers are considered among the most preferred devices for energy dissipation. Therefore, in this research, VE dampers are implemented at strategic locations in a realistic case study structure to increase the level of distributed damping without occupying significant architectural space and reducing earthquake vibrations in terms of story displacements(drifts) and other design forces. It has been concluded that the seismic response of the considered structure retrofitted with supplemental VE dampers corresponded well in controlling the displacement demands. Moreover, it has been demonstrated that seismic response in terms of interstory drifts was effectively mitigated with supplemental damping when added up to a certain level. Exceeding the supplemental damping from this level did not contribute to additional mitigation of the seismic response of the considered structure. In addition, it was found that the supplemental damping increased the total acceleration of the considered structure at all floor levels, which indicates that for irregular tall structures of this type, VE dampers were only a good retrofitting measure for earthquake induced interstory deformations and their use may not be suitable for acceleration sensitive structures. Overall, the research findings demonstrate how seismic hazards to these types of structures can be reduced by introducing additional damping into the structure. 展开更多
关键词 VISCOELASTIC DAMPERS SEISMIC ANALYSIS ASYMMETRIC structure nonlinear MODAL time history ANALYSIS
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Biological characteristics of dynamic expression of nerve regeneration related growth factors in dorsal root ganglia after peripheral nerve injury 预览
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作者 Yin-Ying Shen Xiao-Kun Gu +3 位作者 Rui-Rui Zhang Tian-Mei Qian Shi-Ying Li Sheng Yi 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第8期1502-1509,共8页
The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regen... The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regeneration.Our previous study observed the dynamic changes of genes in L4–6 dorsal root ganglion after rat sciatic nerve crush using transcriptome sequencing.Our current study focused on upstream growth factors and found that a total of 19 upstream growth factors were dysregulated in dorsal root ganglions at 3,9 hours,1,4,or 7 days after nerve crush,compared with the 0 hour control.Thirty-six rat models of sciatic nerve crush injury were prepared as described previously.Then,they were divided into six groups to measure the expression changes of representative genes at 0,3,9 hours,1,4 or 7 days post crush.Our current study measured the expression levels of representative upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin genes,and explored critical signaling pathways and biological process through bioinformatic analysis.Our data revealed that many of these dysregulated upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin,participated in tissue remodeling and axon growth-related biological processes Therefore,the experiment described the expression pattern of upstream growth factors in the dorsal root ganglia after peripheral nerve injury.Bioinformatic analysis revealed growth factors that may promote repair and regeneration of damaged peripheral nerves.All animal surgery procedures were performed in accordance with Institutional Animal Care Guidelines of Nantong University and ethically approved by the Administration Committee of Experimental Animals,China(approval No.20170302-017)on March 2,2017. 展开更多
关键词 axon GROWTH bioinformatic ANALYSIS dorsal root ganglia GROWTH factors INGENUITY Pathway ANALYSIS NERVE regeneration peripheral NERVE INJURY rat SCIATIC NERVE crush INJURY transcriptome sequencing upstream regulators
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Modal analysis of the torque converter in different prestress 预览
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作者 张泽宇 Hui Jizhuang +3 位作者 Shi Ze Suo Xuefeng Zhang Xuhui Fan Hongwei 《高技术通讯:英文版》 CAS 2020年第1期61-67,共7页
In order to study the mechanical properties and the dynamic performance of torque converter,to reduce the vibration and noise during the operation and to improve the stability,a 215 mm hydraulic torque converter is ta... In order to study the mechanical properties and the dynamic performance of torque converter,to reduce the vibration and noise during the operation and to improve the stability,a 215 mm hydraulic torque converter is taken as the research object,and modal analyses are performed based on the finite element method.The weak parts of the impeller structure are obtained after calculating the models of the impeller and turbine without prestress.The variation of the modal frequency of the turbine and impeller are obtained under different prestress conditions by calculating different rotational speeds of the transmission shaft.The fundamental frequencies of the impeller and the turbine increase by 0.43%and 4.82%respectively when the rotational speed ranges from 100 rpm to 4500 rpm.The results of the present research indicate that the modal frequencies at different speeds are similar to the fundamental frequencies of the structure.Therefore,it is possible to estimate the vibration characteristics of the structure and optimize the structural design by numerical modal analysis in the static state instead of the dynamic state. 展开更多
关键词 hydraulic torque converter modal analysis PRESTRESS finite element analysis
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Flue Gas Monitoring System With Empirically-Trained Dictionary 预览
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作者 Hui Cao Yajie Yu +1 位作者 Panpan Zhang Yanxia Wang 《自动化学报:英文版》 CSCD 2020年第2期606-616,共11页
The monitoring of flue gas of the thermal power plants is of great significance in energy conservation and environmental protection.Spectral technique has been widely used in the gas monitoring system for predicting t... The monitoring of flue gas of the thermal power plants is of great significance in energy conservation and environmental protection.Spectral technique has been widely used in the gas monitoring system for predicting the concentrations of specific gas components.This paper proposes flue gas monitoring system with empirically-trained dictionary(ETD)to deal with the complexity and biases brought by the uninformative spectral data.Firstly,ETD is extracted from the raw spectral data by an alternative optimization between the sparse coding stage and the dictionary update stage to minimize the error of sparse representation.D1,D2 and D3 are three types of ETD obtained by different methods.Then,the predictive model of component concentration is constructed on the ETD.In the experiments,two real flue gas spectral datasets are collected and the proposed method combined with the partial least squares,the background propagation neural network and the support vector machines are performed.Moreover,the optimal parameters are chosen according to the 10-fold root-mean-square error of cross validation.The experimental results demonstrate that the proposed method can be used for quantitative analysis effectively and ETD can be applied to the gas monitoring systems. 展开更多
关键词 Dictionary learning empirically-trained dictionaty(ETD) flue gas monitoring system quantitative analysis
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尿毒症维持性血液透析患者发生腹主动脉钙化的危险因素分析
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作者 魏学婷 崔汉民 +3 位作者 丁宁 白久旭 武元赫 曹宁 《中国实用乡村医生杂志》 2020年第1期59-61,64,共4页
目的分析维持性血液透析治疗的尿毒症患者发生腹主动脉钙化的危险因素。方法选取20172018年在北部战区总医院血液净化中心进行维持性血液透析治疗的尿毒症患者112例,收集所有患者临床相关资料进行回顾性分析,同时依据是否有腹主动脉钙... 目的分析维持性血液透析治疗的尿毒症患者发生腹主动脉钙化的危险因素。方法选取20172018年在北部战区总医院血液净化中心进行维持性血液透析治疗的尿毒症患者112例,收集所有患者临床相关资料进行回顾性分析,同时依据是否有腹主动脉钙化分为钙化组(62例)和非钙化组(50例),试分析影响腹主动脉钙化发生的因素。结果钙化组年龄、透析龄、合并糖尿病例数、全段甲状旁腺激素、血磷、钙磷乘积水平与非钙化组差异均有统计学意义(P<0.05)。Logistic回归分析显示,年龄、合并糖尿病、钙磷乘积和全段甲状旁腺激素水平是维持性血液透析治疗尿毒症患者发生腹主动脉钙化的危险因素。结论对于高龄、合并糖尿病、高钙磷乘积和高全段甲状旁腺激素水平的维持性血液透析治疗尿毒症患者,应警惕其发生腹主动脉钙化的可能,应定期行相关实验室及腹主动脉钙化检测,以早发现早治疗腹主动脉钙化,提高维持性血液透析治疗尿毒症患者的生存质量及生存率。 展开更多
关键词 尿毒症 维持性血液透析 腹主动脉钙化 危险因素 分析
粗糙脉孢菌产纤维素酶活力条件分析 预览
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作者 李笑峰 张玲秀 赵二劳 《化工时刊》 CAS 2020年第1期19-21,41,共4页
为了获得廉价而高活力的纤维素酶用于实际生产,本试验以硫酸铵分级盐析、葡聚糖凝胶层析纯化的粗糙脉孢菌所产纤维素酶为试材,分析研究了温度、pH及几种金属离子对其活力的影响。结果表明,温度50℃、pH 4.8时,该纤维素酶活力最强。K+对... 为了获得廉价而高活力的纤维素酶用于实际生产,本试验以硫酸铵分级盐析、葡聚糖凝胶层析纯化的粗糙脉孢菌所产纤维素酶为试材,分析研究了温度、pH及几种金属离子对其活力的影响。结果表明,温度50℃、pH 4.8时,该纤维素酶活力最强。K+对纤维素酶活力具有激活作用,Zn 2+、Mg 2+和Cu 2+抑制纤维素酶活力。本研究为粗糙脉孢菌产纤维素酶的进一步研究和应用奠定了基础。 展开更多
关键词 粗糙脉孢菌 纤维素酶 活力 分析
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两种7-羟基香豆素衍生物的合成和NMR分析 预览
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作者 林会平 孙国绍 梁波 《广州化学》 CAS 2020年第1期31-37,共7页
以7-羟基香豆素为原料,通过吡啶催化乙酸酐反应或碳酸铯促进2-溴乙基甲基醚反应,分别合成两种7-羟基香豆素的衍生物。结合分子结构中不同基团或原子的电子效应影响因素,利用NMR对目标化合物进行分析,通过A环上邻位氢、W型间位氢的耦合常... 以7-羟基香豆素为原料,通过吡啶催化乙酸酐反应或碳酸铯促进2-溴乙基甲基醚反应,分别合成两种7-羟基香豆素的衍生物。结合分子结构中不同基团或原子的电子效应影响因素,利用NMR对目标化合物进行分析,通过A环上邻位氢、W型间位氢的耦合常数3J=8.4 Hz、4J=2.5 Hz(4J=2.4 Hz)以及B环上顺式双键耦合常数3J=9.6 Hz,利用1H-NMR、13C-NMR、135°DEPT、1H-1H COSY、HMQC和HMBC谱对氢原子、碳原子的准确化学位移进行归属和验证。 展开更多
关键词 7-羟基香豆素 衍生物 耦合常数 核磁共振波谱 分析
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Identification of protein targets for the antidepressant effects of Kai-Xin-San in Chinese medicine using isobaric tags for relative and absolute quantitation 预览
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作者 Xian-Zhe Dong Dong-Xiao Wang +3 位作者 Tian-Yi Zhang Xu Liu Ping Liu Yuan Hu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期302-310,共9页
Kai-Xin-San consists of Ginseng Radix, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria at a ratio of 3:3:2:2. Kai-Xin-San has been widely used for the treatment of emotional disorders in China. However, no studi... Kai-Xin-San consists of Ginseng Radix, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria at a ratio of 3:3:2:2. Kai-Xin-San has been widely used for the treatment of emotional disorders in China. However, no studies have identified the key proteins implicated in response to Kai-Xin-San treatment. In this study, rat models of chronic mild stress were established using different stress methods over 28 days. After 14 days of stress stimulation, rats received daily intragastric administrations of 600 mg/kg Kai-Xin-San. The sucrose preference test was used to determine depression-like behavior in rats, while isobaric tags were used for relative and absolute quantitation-based proteomics to identify altered proteins following Kai-Xin-San treatment. Kai-Xin-San treatment for 2 weeks noticeably improved depression-like behaviors in rats with chronic mild stress. We identified 33 differentially expressed proteins: 7 were upregulated and 26 were downregulated. Functional analysis showed that these differentially expressed proteins participate in synaptic plasticity, neurodevelopment, and neurogenesis. Our results indicate that Kai-Xin-San has an important role in regulating the key node proteins in the synaptic signaling network, and are helpful to better understand the mechanism of the antidepressive effects of Kai-Xin-San and to provide objective theoretical support for its clinical application. The study was approved by the Ethics Committee for Animal Research from the Chinese PLA General Hospital(approval No. X5-2016-07) on March 5, 2016. 展开更多
关键词 BRAIN-DERIVED neurotrophic factor signal pathway depression ISOBARIC tags for RELATIVE and absolute quantitation Kai-Xin-San neurogenesis protein network proteomics analysis synaptic plasticity traditional Chinese medicine
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农村集体经济发展中经营内容和组织模式研究分析——以重庆市为例 预览
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作者 李晓波 樊莉 《安徽农业科学》 CAS 2020年第4期224-226,共3页
通过调查对重庆市16个区县195个自然村农村集体经济发展情况,对集体经济发展中的经营内容和组织模式对农村集体经济发展的影响进行总结、分类,对经营内容和组织模式进行方差分析,对组织模式与经营内容进行交互分析,认为经营内容和组织... 通过调查对重庆市16个区县195个自然村农村集体经济发展情况,对集体经济发展中的经营内容和组织模式对农村集体经济发展的影响进行总结、分类,对经营内容和组织模式进行方差分析,对组织模式与经营内容进行交互分析,认为经营内容和组织模式在农村集体经济发展中存在非常密切的相关性,对进一步研究农村集体经济,深化农村集体经济制度改革、激发农村集体经济的发展活力具有重要意义。 展开更多
关键词 农村集体经济 经营内容 组织模式 分析
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宣城市1909号台风“利奇马”灾害过程分析及气象服务概况 预览
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作者 何桂霞 吴迎春 《农业灾害研究》 2020年第1期26-27,36,共3页
第9号(1909号)台风“利奇马”是2019年以来登陆我国的最强台风,具有强度强、历时长、影响范围大等特点。“利奇马”台风给宣城市带来强降水和大风,全市受灾严重,特别是所辖宁国市受灾最为严重。对“利奇马”台风灾害过程进行分析,并对... 第9号(1909号)台风“利奇马”是2019年以来登陆我国的最强台风,具有强度强、历时长、影响范围大等特点。“利奇马”台风给宣城市带来强降水和大风,全市受灾严重,特别是所辖宁国市受灾最为严重。对“利奇马”台风灾害过程进行分析,并对此次台风的气象服务情况进行概述。 展开更多
关键词 台风 利奇马 灾害 分析
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