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中药外敷联合滑膜炎颗粒口服及功能锻炼对膝骨关节炎性滑膜炎临床观察 被引量:21
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作者 张康乐 郭艳幸 《风湿病与关节炎》 2016年第6期18-20,共3页
目的:观察中药外敷联合滑膜炎颗粒口服及功能锻炼治疗膝骨关节炎性滑膜炎的临床疗效。方法:将90例膝骨关节炎性滑膜炎患者随机分为对照组和治疗组,每组45例。对照组给予滑膜炎颗粒口服、功能锻炼治疗,治疗组在对照组治疗基础上加用中药... 目的:观察中药外敷联合滑膜炎颗粒口服及功能锻炼治疗膝骨关节炎性滑膜炎的临床疗效。方法:将90例膝骨关节炎性滑膜炎患者随机分为对照组和治疗组,每组45例。对照组给予滑膜炎颗粒口服、功能锻炼治疗,治疗组在对照组治疗基础上加用中药外敷患膝关节,2组疗程均为30 d。对2组临床疗效、膝关节肿胀评分及HSS评分进行比较。结果:治疗组显效20例,有效22例,无效3例,总有效率为93.33%;对照组显效11例,有效28例,无效6例,总有效率为86.67%。2组比较,差异无统计学意义(P>0.05)。治疗后,2组膝关节肿胀评分、HSS评分较治疗前均有改善(P<0.05),且治疗组优于对照组(P<0.05)。结论:中药外敷联合滑膜炎颗粒口服及功能锻炼治疗膝骨关节炎性滑膜炎疗效确切。 展开更多
关键词 骨关节炎 膜炎 膜炎颗粒 中药外敷 功能锻炼
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Electrical Characteristics of Tangjiawan Landslide in Lixian, Sichuan
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作者 Bin Li Qiang Xu +4 位作者 Qiang Cheng Tian-Xiang Liu Jian-hua Yu Yu-jie Su Feng Wang 《Applied Geophysics》 SCIE CSCD 2024年第3期549-563,619,共16页
A wide range of terrain features and landforms,which are exemplified by intricate geological formations and diverse rock compositions,are found in the western mountainous regions of China.These areas frequently encoun... A wide range of terrain features and landforms,which are exemplified by intricate geological formations and diverse rock compositions,are found in the western mountainous regions of China.These areas frequently encounter geological disasters.As one of the natural disasters,landslides lead to considerable loss of human life and property.Considering mitigation of the losses caused by landslide disasters,a necessary measure for disaster prevention and mitigation involves conducting detailed investigations and monitoring of landslides,which is also the cornerstone of landslide warning.This study compares and analyzes the feasibility of the magnetotelluric detection method for landslides using the results of engineering geological surveys and landslide monitoring.The study aims to address the scientific problem of the validity of using magnetotelluric methods to detect landslide development processes.The Tangjiawan landslide signal on the left side of the K94+000~K94+145 section of the Wenma Expressway is analyzed by employing engineering geological survey,magnetotelluric detection,landslide monitoring,landslide analysis,and other methods.Analysis results provide the static electrical characteristics of lithology,structure,and groundwater,as well as the dynamic electrical characteristics of landslide development.This study focuses on analyzing the relationship between the methods of magnetotelluric detection and engineering geological surveys and the results of landslide monitoring.The workflow and methods for data collection,processing,inversion,interpretation,and analysis using the magnetotelluric method to detect the dynamic development process of landslides are presented in the conclusion.Preliminary conclusions indicate a strong correlation between the dynamic changes in magnetotelluric wave impedance with the surface displacement of landslides and the dynamic changes in groundwater.The use of the magnetotelluric method for landslide detection and monitoring is a feasible example.The research results can offer certain technical references for the detection and monitoring of landslides using magnetotelluric methods and also provide references and guidance for the selection of diversified landslide monitoring methods in the future. 展开更多
关键词 LANDSLIDE Magnetotelluric method GEOPHYSICS Engineering Geology Landslide Monitoring
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Effects of frothers on bubbles size and flotation performance of hydrophobic minerals
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作者 Gülşah GÜVEN Berivan TUNÇ +1 位作者 ŞBeste AYDIN Gülay BULUT 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2280-2299,共20页
Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable froths.The collision probability of the bubbles and particles substantially increases by decreasing bubble si... Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable froths.The collision probability of the bubbles and particles substantially increases by decreasing bubble size.For the same volume system,fewer bubbles result from a distribution of large-sized bubbles,and more bubbles result from a distribution of small-sized bubbles.In this research,fundamental two-phase frother characterization parameters were aimed to link with three-phase coal and talc flotation behavior.For this purpose,the effect of single and dual frother systems on inhibiting bubble coalescence was investigated with methyl isobutyl carbinol(MIBC),isooctanol(2 ethyl hexanol),pine oil,and Dowfroth 250.Based on the results of single frothers,isooctanol at the lowest critical coalescence concentration(CCC)value of 6×10^(−6) achieved the smallest bubbles with Sauter mean diameter of 0.80 mm.By blending Dowfroth 250 and pine oil,the bubbles size decreased significantly,reaching 0.45 mm.While the highest recoveries in coal flotation were obtained in single and frother blends where the bubbles size was measured as the smallest in two-phase system,and such a relationship was not found for talc flotation. 展开更多
关键词 FLOTATION frother blends bubble size coal and talc flotation
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Effect of wire diameter compression ratio on drawing deformation of micro copper wire
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作者 Tao HUANG Han-jiang WU +3 位作者 Ke-xing SONG Yan-min ZHANG Yan-jun ZHOU Shao-lin LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2605-2618,共14页
A crystal plasticity finite element model was developed for the drawing deformation of pure copper micro wire,based on rate-dependent crystal plasticity theory.The impact of wire diameter compression ratio on the micr... A crystal plasticity finite element model was developed for the drawing deformation of pure copper micro wire,based on rate-dependent crystal plasticity theory.The impact of wire diameter compression ratio on the micro-mechanical deformation behavior during the wire drawing process was investigated.Results indicate that the internal deformation and slip of the drawn wire are unevenly distributed,forming distinct slip and non-slip zones.Additionally,horizontal strain concentration bands develop within the drawn wire.As the wire diameter compression ratio increases,the strength of the slip systems and the extent of slip zones inside the deformation zone also increase.However,the fluctuating stress state,induced by contact pressure and frictional stress,results in a rough and uneven wire surface and diminishes the stability of the drawing process. 展开更多
关键词 micro copper wire drawing deformation crystal plasticity finite element slip mode
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Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions
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作者 ZHU Qiang YIN Qian +9 位作者 TAO Zhi-gang HE Man-chao ZHENG Bo-wen JING Hong-wen REN Shu-lin ZHANG Qiang MENG Bo BAI Dong-feng WU Sai-sai WU Jiang-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2393-2410,共18页
A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating... A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological disasters.This study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads,investigating the shear behaviors of joints across varying initial normal loads,normal loading frequencies,and normal loading amplitudes.Experimental results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading amplitudes.Dynamic normal loading can either increase or decrease shear strength,while this study demonstrates that higher frequencies lead to enhanced friction.Increased initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient(JRC)values of joint surfaces after shearing.Positive correlations existed between frictional energy dissipation and peak shear forces,while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression analysis.This study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances. 展开更多
关键词 dynamic normal displacement shear strength variations phase lag phenomenon STICK-SLIP
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Semi-analytical solution for mechanical analysis of tunnels crossing strike-slip fault zone considering nonuniform fault displacement and uncertain fault plane position
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作者 YANG Heng-hong WANG Ming-nian +1 位作者 YU Li ZHANG Xiao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2116-2136,共21页
The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-e... The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-earthquake observations indicate that the displacement near the fault zone is typically nonuniform,and the fault plane position is uncertain.In this study,we first established a series of improved governing equations to analyze the mechanical response of tunnels under strike-slip fault dislocation.The proposed methodology incorporated key factors such as nonuniform fault displacement and uncertain fault plane position into the governing equations,thereby significantly enhancing the applicability range and accuracy of the model.In contrast to previous analytical models,the maximum computational error has decreased from 57.1%to 1.1%.Subsequently,we conducted a rigorous validation of the proposed methodology by undertaking a comparative analysis with a 3D finite element numerical model,and the results from both approaches exhibited a high degree of qualitative and quantitative agreement with a maximum error of 9.9%.Finally,the proposed methodology was utilized to perform a parametric analysis to explore the effects of various parameters,such as fault displacement,fault zone width,fault zone strength,the ratio of maximum fault displacement of the hanging wall to the footwall,and fault plane position,on the response of tunnels subjected to strike-slip fault dislocation.The findings indicate a progressive increase in the peak internal forces of the tunnel with the rise in fault displacement and fault zone strength.Conversely,an augmentation in fault zone width is found to contribute to a decrease in the peak internal forces.For example,for a fault zone width of 10 m,the peak values of bending moment,shear force,and axial force are approximately 46.9%,102.4%,and 28.7% higher,respectively,compared to those observed for a fault zone width of 50 m.Furthermore,the position of the peak internal forces is influenced by variations in the ratio of maximum fault displacement of the hanging wall to footwall and the fault plane location,while the peak values of shear force and axial force always align with the fault plane.The maximum peak internal forces are observed when the footwall exclusively bears the entirety of the fault displacement,corresponding to a ratio of 0:1.The peak values of bending moment,shear force,and axial force for the ratio of 0:1 amount to approximately 123.8%,148.6%,and 111.1% of those for the ratio of 0.5:0.5,respectively. 展开更多
关键词 strike-slip fault tunnel engineering semi-analytical solution fault zone width nonuniform fault displacement uncertain fault plane position
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滑旱冰的启示
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作者 李沁玥 《小学生作文选刊(中高年级)》 2010年第7期45-45,共1页
最近这些天晚上,我写完作业后,都会和爸爸一起出去锻炼身体。
关键词 《滑旱冰的启示》 小学生 作文 语文学习
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滑滑板
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作者 杨可晖 潘蓉 《新作文(小学低年级版)》 2009年第7期30-31,38,共3页
奶奶爱花,所以养了许多花。大大小小几十盆花摆满了阳台、客厅。淘气的我常常趁奶奶不注意掐几朵小花,拽几片叶子,可唯独对那盆足球般大小的仙人球敬而远之。
关键词 《滑板》 小学 作文 杨可晖
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滑滑梯
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作者 孙婉蓁 《百家作文指导(小学低年级版.全国小语会刊)》 2009年第10期35-35,共1页
怎么样,好看吧?你肯定特别想读吧?下面这篇小作文,就是孙婉蓁小朋友在读完这本图画书后看着其中的一幅图写的,我们快来读吧!
关键词 《滑梯》 小学 作文 孙婉蓁
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滑旱冰
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作者 方圆 《小学生作文辅导(语文园地)》 2010年第3期6-7,共2页
要写出人物的特点,最重要的是写出人物做什么,是怎样做的,也就是写好人物的动作。
关键词 《滑旱冰》 小学 作文 语文教学
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Corrosion resistance of in-situ Mg-Al hydrotalcite conversion film on AZ31 magnesium alloy by one-step formation 被引量:14
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作者 曾荣昌 刘振国 +4 位作者 张芬 李硕琦 赫庆坤 崔洪芝 韩恩厚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1917-1925,共9页
In situ growth of nano-sized layered double hydroxides (LDH) conversion film on AZ31 alloy was synthesized by a urea hydrolysis method. The formation mechanism of the film was proposed. Firstly, the dissolved Mg2+ ... In situ growth of nano-sized layered double hydroxides (LDH) conversion film on AZ31 alloy was synthesized by a urea hydrolysis method. The formation mechanism of the film was proposed. Firstly, the dissolved Mg2+ ions deposited into a precursor film consisted of MgCO3 and Mgs(CO3)4(OH)2·4H2O; secondly, the precursor translated into the crystalline Mg(OH)2 in alkaline conditions; finally, the Mg2+ ions in Mg(OH)z were replaced by A13+ ions, Mg(OH)2 translated into the more stable LDH structure, simultaneously, the OH- ions in the interlayer were exchanged by CO32-, thus led to the formation of the LDH (Mg6Alz(OHh6CO3·4H2O) film. The results indicated that the LDH film characterized by interlocking plate-like nanostructures and ion-exchange ability significantly improved the corrosion resistance of the AZ31 Mg alloy. 展开更多
关键词 magnesium alloy HYDROTALCITE conversion film corrosion resistance ion-exchange
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Molecular Cloning and Expression Analysis of FTZ-F1 in the Half-smooth Tongue-sole, Cynoglossus semilaevis 被引量:9
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作者 邓思平 陈松林 刘本伟 《Zoological Research》 CAS CSCD 北大核心 2008年第6期592-598,共7页
To investigate the expression characteristics of sex related gene of FTZ-F 1 in the half-smooth tongue-sole (Cynoglossus semilaevis), the homologue FTZ-F1 (hsFTZ-F1) full-length cDNA was isolated from the testis b... To investigate the expression characteristics of sex related gene of FTZ-F 1 in the half-smooth tongue-sole (Cynoglossus semilaevis), the homologue FTZ-F1 (hsFTZ-F1) full-length cDNA was isolated from the testis by homologous cloning, and the cDNA included the open reading frame and a 66bp 5'-UTR, along with a 1619bp 3'-UTR, encoding a predicted 485 amino acid protein. Sequence, tissue distribution and phylogenic analyses of the FTZ-F1 showed that the hsFTZ-F1 belonged to SF-1/Ad4BP group. The hsFTZ-F1 transcripts were highly abundant in the gonads, kidneys, brain and head-kidneys, but weakly in other tissues. However, the expression level in the brain and head-kidney of female was highly abundant than in the male. The hsFTZ-F1 expression was highly abundant in the embryo than in the larvae, which suggested that the hsFTZ-F1 may be involved in the organogenesis in the tongue sole. 展开更多
关键词 Cynoglossus semilaevis FTZ-F1 cDNA cloning Expression
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Superlubricity behaviors of Nitinol 60 alloy under oil lubrication 被引量:6
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作者 曾群锋 董光能 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期354-359,共6页
The tribological tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disc in the tribometer system. Four kinds of oils were experimentally investigated as lubrication oils for lubricating Nitinol ... The tribological tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disc in the tribometer system. Four kinds of oils were experimentally investigated as lubrication oils for lubricating Nitinol 60 alloy in the boundary lubrication regime. The experimental results were compared with a reference dry friction. It was found that Nitinol 60 alloy can be lubricated significantly and has shown remarkable lubrication performance. A superlubricity behavior of Nitinol 60 alloy was observed under castor oil lubrication. An ultra-low coefficient of friction of Nitinol 60 alloy about 0.008 between Nitinol 60 alloy and GCr15 steel was obtained under castor oil lubrication condition after a running-in period. Accordingly, the present study is focused on the lubrication behaviors of castor oil as potential lubrication oil for Nitinol 60 alloy. In the presence of castor oil, coefficient of friction is kept at 0.008 at steady state, corresponding to so-called superlubricity regime (when sliding is then approaching pure rolling). The mechanism of superlubricity is attributed to the triboformed OH-terminated surfaces from friction-induced dissociation of castor oil and the boundary lubrication films formed on the contact surface due to high polarity and long chain of castor oil allowing strong interactions with the lubricated surfaces. 展开更多
关键词 Nitinol 60 alloy oil lubrication SUPERLUBRICITY lubrication films
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Low temperature quasi-superplasticity of ZK60 alloy prepared by reciprocating extrusion 被引量:5
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作者 杨文朋 郭学锋 杨凯军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期255-261,共7页
Fine-grained ZK60 alloy was prepared by 2-pass reciprocating extrusion, and the low temperature superplasticity was conducted in a temperature range from 443 to 523 K and an initial strain rate ranging from 3.3×1... Fine-grained ZK60 alloy was prepared by 2-pass reciprocating extrusion, and the low temperature superplasticity was conducted in a temperature range from 443 to 523 K and an initial strain rate ranging from 3.3×10^-4 to 3.3×10-2^s^-1. The results show that the alloy has an equiaxed grain structure with an average grain size of about 5.0μm, and the sizes of broken secondary particles and precipitates are no more than 175 and 50 nm, respectively. The alloy exhibits quasi-superplasticity with a maximum elongation of 270% at 523 K and an initial strain rate of 3.3×10^-4 s^-1. The strain rate sensitivity m is less than 0.2 at 443 and 473 K, and it is 0.42 at 523 K. The apparent activation energies at temperature below 473 K and at 523 K are less than 63.2 and 110.6 kJ/mol, respectively At temperature below 473 K, mainly intragranular sliding contributes to superplastic flow. At 523 K, grain boundary sliding is the dominant deformation mechanism, and dislocation creep controlled by grain boundary diffusion is considered to be the main accommodation mechanism. 展开更多
关键词 ZK60 Mg alloy reciprocating extrusion QUASI-SUPERPLASTICITY intragranular sliding grain boundary sliding
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EFFECT OF COOLING/LUBRICATION MEDIUM ON MACHINABILITY OF Ti6Al4V 被引量:5
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作者 戚宝运 何宁 李亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第3期225-230,共6页
To better understand and know the roles of cooling/lubrication medium in the cutting process and expand their applicability,uncoated cemented carbide tools are used in high-speed turning Ti6Al4V.Dry,cold air,minimal q... To better understand and know the roles of cooling/lubrication medium in the cutting process and expand their applicability,uncoated cemented carbide tools are used in high-speed turning Ti6Al4V.Dry,cold air,minimal quantity lubrication(MQL),cryogenic MQL,and ionized air as the cooling/lubrication conditions are studied.Experimental results show that at speed 120 m/min turning Ti6Al4V,the cutting force under ionized air is smallest under all lubricant conditions,and tool life is best,next is cryogenic MQL.MQL and cold air almost have the same effect,a little better than dry.Meanwhile the smallest surface roughness is also obtained under ionized air condition.Flank wear and crater wear are the dominant failure modes when high-speed turning Ti6Al4V by SEM analysis.Finally the conclusion is drawn that ionized air and cryogenic MQL have better cooling/lubrication effects and can effectively improve the tool life. 展开更多
关键词 cooling/lubrication high-speed turning TI6AL4V minimal quantity lubrication(MQL) ionized air
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Landslide disaster in the loess area of China 被引量:16
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作者 周金星 朱春云 +2 位作者 郑景明 王晓慧 刘洲鸿 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期157-161,165,共5页
China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and bec... China is the country with most widely distributed loess area in the world, and its loess area accounts of 6.63% of total nation land area. The landslide disaster occurs frequently for complex natural condition and becomes major factors hindering the social and economic development of loess regions. Through different indexes, the authors divided the landslides into 9 principal types and analyzed the distribution characteristics of loess landslide in time and space, the affecting factors and mechanism of landslides. It is pointed out that time and spatial distributions of landslides are closely correlative to topographic and geomorphic conditions, earthquake and rainfall, and the key influencing factors include topography, geomorphology, new tectonic movements, earthquake activity, surface water, ground water and human activities. The authors emphasized that the natural condition of loess areas was favorable to landslides, human activities impelled its occurrence and that controlling the loess landslide was an urgent task for sustainable development in the loess zone. 展开更多
关键词 Loess landslide Landslide mechanism Natural disasters
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Cloning of hemoglobin-α1 from half-smooth tongue sole (Cynoglossus semilaevis) and its expression under short-term hypoxia 被引量:5
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作者 王资生 齐志涛 +5 位作者 田敬云 仇明 赵卫红 王爱民 黄金田 郭锡杰 《Zoological Research》 CAS CSCD 北大核心 2011年第6期641-646,共6页
This study cloned the hemoglobin a1 from the marine teleost, the half-smooth tongue sole (Cynoglossus semilaevis), and then examined its expression under hypoxia exposure. The full-length of CsHb-a1 (594 bp) cDNA ... This study cloned the hemoglobin a1 from the marine teleost, the half-smooth tongue sole (Cynoglossus semilaevis), and then examined its expression under hypoxia exposure. The full-length of CsHb-a1 (594 bp) cDNA contains an open reading frame encoding 144 amino acids. Sequence analysis shows that the predicted CsHb-a1 amino acids shares high identities with that of other species. Real-time PCR showed that CsHb-a1 was highly expressed in the heart, liver, spleen, kidney and blood. Five to 120 min esposure and long-term (36 h) exposure to hypoxia (1.0 mg/L) significantly increased CsHb-a1 mRNA expression in most tissues compared to those fish held in normoxic conditions (dissolved oxygen (DO): 6.2 mg/L). These results suggested that the up-regulation of Hb-a1 is an important component for adaptation of half-smooth tongue sole to short-term hypoxia. 展开更多
关键词 Cynoglossus semilaevis HEMOGLOBIN Gene clone Hypoxia stress
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Advance and trend of friction study in plastic forming 被引量:8
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作者 王丹 杨合 李恒 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1263-1272,共10页
Friction is a critical issue in plastic forming which influences forming force, metal flow, forming quality and service life of die. Since friction is a highly nonlinear physical phenomenon which is interactively affe... Friction is a critical issue in plastic forming which influences forming force, metal flow, forming quality and service life of die. Since friction is a highly nonlinear physical phenomenon which is interactively affected by so many factors, great efforts have been made to study the friction mechanism and controlling. The research progress of friction issues in plastic forming was summarized and discussed from four aspects: testing, characterizing, modeling and optimization/controlling. Considering urgent demands for green, efficient and precise forming of high-performance, lightweight and complex components in high-tech industries such as aerospace and automotive, the trends and challenges of friction study in plastic forming were proposed. 展开更多
关键词 plastic forming friction model LUBRICANT friction coefficient
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Lubrication properties of Nitinol 60 alloy used as high-speed rolling bearing and numerical simulation of flow pattern of oil-air lubrication 被引量:2
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作者 曾群锋 赵西朦 +1 位作者 董光能 吴红星 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2431-2438,共8页
The friction and wear tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disk in a pin-on-disk tribometer system under PAO oil lubrication conditions. It was found that Nitinol 60 alloy can be lu... The friction and wear tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disk in a pin-on-disk tribometer system under PAO oil lubrication conditions. It was found that Nitinol 60 alloy can be lubricated well and has shown remarkable tribological performance. Average coefficient of friction (COF) of Nitinol 60 is 0.6 under dry friction; however, average COF decreases to 0.1 under PAO oil lubrication. SEM image of the worn surface shows that Nitinol 60 exhibits excellent wear resistance and the wear mechanism is mainly adhesive wear. Flow pattern of oil-air flow in oil pipe was simulated by FLUENT software with VOF model for acquiring working performance of oil-air lubrication. The optimum velocity of oil and air at the inlet was achieved, which provides the great proposal for the design of experiment of oil-air lubrication of Nitinol 60 alloy. The simulation results showed that the optimum annular flow of flow pattern was obtained when air velocity is 10 m/s and oil velocity is 0.05 m/s. The formation mechanism of annular flow was also discussed in the present study. 展开更多
关键词 Nitinol 60 alloy lubrication properties oil-air lubrication numerical simulation two-phase flow
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Synthesis and highly efficient photocatalytic activity of mixed oxides derived from ZnNiAl layered double hydroxides 被引量:6
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作者 张丽 戴超华 +2 位作者 张秀秀 刘又年 阎建辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2380-2389,共10页
ZnO/NiO/ZnAl2O4 mixed-metal oxides were successfully synthesized through a hydrotalcite-like precursor route, in which appropriate amounts of metal salts solutions were mixed to obtain a new series of ZnNiAl layered d... ZnO/NiO/ZnAl2O4 mixed-metal oxides were successfully synthesized through a hydrotalcite-like precursor route, in which appropriate amounts of metal salts solutions were mixed to obtain a new series of ZnNiAl layered double hydroxides(LDHs) as precursors, followed by calcination under different temperatures. The as-obtained samples were characterized by SEM, HRTEM, TEM, XRD, BET, TG-DTA, and UV-Vis spectra techniques. The photocatalytic activities of the samples were evaluated by degradation of methyl orange(MO) under the simulated sunlight irradiation. The effects of Zn/Ni/Al mole ratio and calcination temperature on the composition, morphology and photocatalytic activity of the samples were investigated in detail. The results indicated that compared with ZnNiAl-LDHs, the mixed-metal oxide showed superior photocatalytic performance for the degradation of MO. A maximum of 97.3% photocatalytic decoloration rate within 60 min was achieved from the LDH with the Zn/Ni/Al mole ratio of 2:1:1 and the calcination temperature of 500 ℃, which much exceeded that of Degussa P25 under the same conditions. The possible mechanism of photocatalytic degradation over ZnO/NiO/ZnAl2O4 was discussed. 展开更多
关键词 ZnNiAl layered double hydroxide mixed oxide photocatalytic degradation phototatalytic activity
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