检索结果-南通市图书馆

Catalytic aquathermolysis of Shengli heavy crude oil with an amphiphilic cobalt catalyst

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2016年第3期13卷 463-475页

作者： Yan-Bin Cao Long-Li Zhang Dao-hong xia State Key Laboratory of Heavy Oil Processing China University of Petroleum Research Institute of Petroleum Engineering and Technology Shengli Oilfield CompanySinopec

An interfacially active cobalt complex,cobalt dodecylbenzenesulfonate,was *** analysis,atomic absorption spectroscopy,Fourier transform infrared spectroscopy（FT-IR）,thermogravimetric analysis,and surface/interfacial tension determination were performed to investigate the properties of the *** showed that the synthesized catalyst showed active interfacial behavior,decreasing the surface tension and interfacial tension between heavy oil and liquid phase to below 30 and 1.5 mN/m,*** catalyst was not thermally degraded at a temperature of 400 ℃,indicating its high thermal *** performance of the catalyst was evaluated by carrying out *** viscosity determination showed that the viscosity of the heavy oil decreased by 38%.The average molecular weight,group compositions,and average molecular structure of various samples were analyzed using elemental analysis,FT-IR,electrospray ionization Fourier transform ion cyclotron resonance（ESI FT-ICR MS）,and ～1H nuclear magnetic *** indicated that the catalyst could attack the sulfur- and O_2-type heteroatomic compounds in asphaltene and resin,especially the compounds with aromatic structure,leading to a decrease in the molecular weight and then the reduction in the viscosity of heavy ***,the synthesized catalyst might find an application in catalytic aquathermolysis of heavy oil,especially for the high-aromaticity heavy oil with high oxygen content.

关键词： Interfacially active CoDBS Catalytic aquathermolysis Oxygen-contained groups Heavy oil

Changes in Activities of Antioxidant-Related Enzymes in Leaves of Resistant and Susceptible Wheat Inoculated with Rhizoctonia cerealis

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2011年第4期10卷 526-533页

作者： LIU hong-xia XIN Zhi-yong ZHANG Zeng-yan National Key Facility for Crop Gene Resources and Genetic Improvement~Institute of Crop Sciences Chinese Academy of AgriculturalSciences Beijing 100081 P.R. China

In this study, the changes in activities of peroxidase （POD）, glutathione S-transferase （GST）, catalase （CAT）, and superoxide distmuase （SOD） in leaves of four wheat cultivars, including resistant cultivars Shannong 0431 and Shanhongmai, a mildsusceptible cultivar Lumai 21, and a susceptible cultivar Wenmai 6, were investigated to explore if these antioxidantrelated enzymes were involved in wheat defense response to Rhizoctonia cerealis attack. Results showed that the activities of these enzymes in different wheat cultivars varied greatly after challenging with R. cerealis. The POD activities in resistant cultivars Shannong 0431 and Shanhongmai increased much quicker after the inoculation and displayed much higher activity than that in susceptible cultivar Wenmai 6. In contrast, POD activity showed a slow accumulation and a delayed peak time. The activities of GST and CAT in Shannong 0431 and Lumai 21 increased obviously within 48 h post inoculation （hpi）, whereas SOD activity decreased dramatically within 24 hpi in Shannong 0431 and 24-48 hpi in Lumai 21. In susceptible cultivar Wenmai 6, the SOD and CAT activities didn’t change obviously, whereas the activity of GST was decreased. The activities of CAT and GST in Shanhongmai did not show significant difference compared with those in Wenmai 6. Results suggested that POD activity may be positively associated with wheat defense to R. cerealis.

关键词： wheat Rhizoctonia cerealis antioxidant-related enzymes peroxidase

Higher-Order Lagrangian Equations of Higher-Order Motive Mechanical System

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第2期49卷 479-481页

作者： ZHAO hong-xia MA Shan-Jun SHI Yong College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China

In this paper, if the condition of variation δt = 0 is satisfied, the higher-order Lagrangian equations and higher-order Hamilton＇s equations, which show the consistency with the results of traditional analytical mechanics, are obtained from the higher-order Lagrangian equations and higher-order Hamilton＇s equations. The results can enrich the theory of analytical mechanics.

关键词： higher-order Lagrange function Hamilton function higher-order Lagrangian equation

Vibrating-Sliding Motion of Caisson Breakwaters Under Various Breaking Wave Impact Forces

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2003年第4期18卷 565-576页

作者： WANG Yuan-zhan(王元战) YU hong-xia(于红霞) Department of Port and Coastal Engineering School of Civil Engineering Tianjin University Tianjin300072 China Department of Port and Coastal Engineering School of Civil Engineering Tianjin University Tianjin300072 China

Sliding is one of the principal failure types of caisson breakwaters and is an essential content of stability examination in caisson breakwater design. Herein, the mass-spring-dashpot model of caisson-base system is used to simulate the vibrating-sliding motion of the caisson under various types of breaking wave impact forces, i.e., single peak impact force, double peak impact force, and shock-damping oscillation impact force. The effects of various breaking wave impacts and the sliding motion on the dynamic response behaviors of caisson breakwaters are investigated and the calculation of relevant system parameters is discussed. It is shown that the dynamic responses of the caisson are significantly different under different types of breaking wave impact forces even when the amplitudes of impact forces are equal. The amplitude of dynamic response of the caisson is lower under single peak impact excitation than that under double peak impact or shock-damping oscillation impact excitation. Though the displacement of the caisson is large due to sliding, the rotation, the sliding force and the overturning moment of the caisson are significantly reduced.

关键词： breakwater various types of breaking wave impact vibrating-sliding motion

Soliton, Positon and Negaton Solutions of Extended KdV Equation

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第3期49卷 529-534页

作者： WU hong-xia ZENG Yun-Bo FAN Tian-You Department of Mathematics Jimei University Xiamen 361021 China Department of Mathematics Beijing Institute of Technology Beijing 100081 China Department of Mathematical Sciences Tsinghua University Beijing 100084 China

Darboux transformation （DT） provides us with a comprehensive approach to construct the exact and explicit solutions to the negative extended KdV （eKdV） equation, by which some new solutions such as singular soliton, negaton, and positon solutions are computed for the eKdV equation. We rediscover the soliton solution with finiteamplitude in [A.V. Slyunyaev and E.N. Pelinovskii, J. Exp. Theor. Phys. 89 （1999） 173] and discuss the difference between this soliton and the singular soliton. We clarify the relationship between the exact solutions of the eKdV equation and the spectral parameter. Moreover, the interactions of singular two solitons, positon and negaton, positon and soliton, and two positons are studied in detail.

关键词： the extended KdV equation singular soliton positon negaton Darboux transformation

Causes for the Unimodal Pattern of Leaf Carbon Isotope Composition in Abies faxoniana Trees Growing in a Natural Forest along an Altitudinal Gradient

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2015年第1期12卷 39-48页

作者： ZHAO hong-xia DUAN Bao-li LEI Yan-bao Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences

Leaf morphological and physiological traits of Abies faxoniana growing in a natural forest along an altitudinal gradient were measured with the aim to identify the central mechanism for the marked variation in foliar δ13C determined by an isotope ratio mass spectrometer. There is a unimodal pattern of plant functional traits in these temperate and semi- humid areas. Stomatal parameters, specific leaf area, and C/N ratio increased, whereas C, N and δ13C values decreased with increasing altitude below 3000 m a.s.1. In contrast, they exhibited opposite trends above 3000 m a.s.l.. Our results demonstrated that high-altitude plants achieve higher water use efficiency （WUE） at the expense of decreasing nitrogen use efficiency （NUE）, whereas plants at 3000 m can maintain a relatively higher NUE but a lower WUE. Such intra-specific differences in the trade-off between NUE and WUE may partially explain the altitudinal distribution of the plants in relation to moisture and nutrient availability. Our results clearly indicate that the functional relations between nutritional status and the structure of leaves are responsible for the altitudinal variations associated with δ13C. The pivotal role of specific leaf area in regulating plant adaptive responses provides a potential physiological mechanism for the observed growth advantage of populations occupying the medium altitude. These adaptive responses altitudinal gradients showed that an altitude to of approximately 3000 m a.s.1, is the optimum distribution zone for A. faxoniana, allowing the most vigorous growth and metabolism. These results improve our understanding of the various roles of environmental and biotic variables upon δ13C dynamics and provide useful information for subalpine coniferous forest management.

关键词： Abiesfaxoniana Age Altitude Carbonisotope ratio Nitrogen content

Comparative proteomes change and possible role in different pathways of micro RNA-21a-5p in a mouse model of spinal cord injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第6期15卷 1102-1110页

作者： Almaghalsa-Ziad Mohammed hong-xia Du hong-Liang Song Wei-Ming Gong Bin Ning Tang-hong Jia Department of Spinal Surgery Jinan Central Hospital Affiliated to Shandong University

Our previous study found that microRNA-21 a-5 p(miR-21 a-5 p)knockdown could improve the recovery of motor function after spinal cord injury in a mouse model,but the precise molecular mechanism remains poorly *** this study,a modified Allen's weight drop was used to establish a mouse model of spinal cord injury.A proteomics approach was used to understand the role of differential protein expression with miR-21 a-5 p knockdown,using a mouse model of spinal cord injury without gene knockout as a negative control *** found that after introducing miR-21 a-5 p knockdown,proteins that played an essential role in the regulation of inflammatory processes,cell protection against oxidative stress,cell redox homeostasis,and cell maintenance were upregulated compared with the negative control *** Encyclopedia of Genes and Genomes pathway enrichment analysis identified enriched pathways in both groups,such as the oxidative phosphorylation pathway,which is relevant to Parkinson's disease,Huntington's disease,Alzheimer's disease,and cardiac muscle *** also found that miR-21 a-5 p could be a potential biomarker for amyotrophic lateral sclerosis,as miR-21 a-5 p becomes deregulated in this *** results indicate successful detection of some important proteins that play potential roles in spinal cord *** the relationship between these proteins and the recovery of spinal cord injury will provide a reference for future research of spinal cord injury *** experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Shandong University of China on March 5,2014.

关键词： bioinformatics biomarker inflammation micro RNA mitochondria mouse pathway analysis proteomics spinal cord injury stathmin

Two New Multi-component BKP Hierarchies

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2009年第2期51卷 193-199页

作者： WU hong-xia LIU xiao-Jun ZENG Yun-Bo Department of Mathematics School of Science Jimei University xiamen China361021 Department of Mathematics China Agricultural University Beijing China100083 Department of Mathematical Sciences Tsinghua University Beijing China100084

We firstly propose two kinds of new multi-component BKP （mcBKP） hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with self-consistent sources whose Lax representations are presented. The two mcBKP hierarchies both admit reductions to the k-constrained BKP hierarchy and to integrable （1＋1）-dimensional hierarchy with self-consistent sources, which include two types of SK equation with self-consistent sources and of hi-directional SK equations with self-consistent

关键词： multi-component BKP hierarchy BKP equation with self-consistent sources κ-constrained BKPhierarchy n-reduction of mcBKP Lax representation

Mechanisms mediating CCK-8S-induced contraction of proximal colon in guinea pigs

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2010年第9期16卷 1076-1085页

作者： Zhu, Jie Chen, Ling xia, hong Luo, He-Sheng Wuhan Univ Renmin Hosp Dept Gastroenterol Wuhan 430060 Hubei Province Peoples R China Wuhan Univ Res Ctr Struct Biol Wuhan 430060 Hubei Province Peoples R China

AIM:To investigate the effects of sulfated cholecystokinin octapeptide (CCK-8S) on the contractile activity of guinea-pig proximal ***:Proximal colonic smooth muscle (PCSM) strips were obtained from adult female guinea pigs and contractile response of PCSM strips was recorded using a *** cells were isolated by enzymatic *** potential (RP),action potential (AP),large conductance potassium channel currents (IBKCa) and L-type calcium currents (ICa-L) were recorded by patch-clamp ***:(1) CCK-8S (10-7 mol/L) enhanced the mean contractile amplitude of colonic circular muscle and longitudinal muscle (LM) strips by 56.53% ± 11.92%(P=0.038) and 65.93% ± 12.98% (P=0.019),respectively,as well as the mean frequency of LM by 31.69% ± 13.58% (P=0.023),which were significantly attenuated by pretreating strips with devazepide,nifedipine,iberiotoxin,thapsigargin (TG) and BAPTA-AM (BA) respectively;(2) CCK-8S (10-7 mol/L) increased the AP amplitude by 38.6% ± 3.2% (P=0.015),decreased AP duration by 36.9% ± 8.7% (P=0.026),and depolarized the RP from-61.3 ± 2.7 mV to-29.8 ± 5.9 mV (P=0.032);and (3) Compared with the normal control group,CCK-8S (10-7 mol/L) enhanced the peak current of IBKCa by 18.7% ± 2.1% (from 916 ± 183 pA to 1088 ± 226 pA;at +60 mV;P=0.029),which was inhibited by respective pretreatment with iberiotoxin and ***,CCK-8S (10-7 mol/L) intensif ied the peak current of ICa-L by 40% (from 60 ± 8 pA to 84 ± 11 pA;at +10 mV;P=0.012),compared to the normal control group,which was apparently suppressed by respective pretreatment with nifedipine,devazepide,TG and *** the respective presence of heparin and staurosporine,CCK-8S did not signif icantly enhance IBKCa and ***:The results suggest that CCK-8S promotes guinea-pig proximal colon contraction by CCK1 receptors,following activation of the inositol triphosphate-protein kinase C signal transduction pathway.

关键词： Muscle contraction Potassium channels Calcium channels Colon Cholecystokinin octapeptide