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SBS母粒法改性沥青的研制及生产 被引量:2
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作者 黄婉利 俞仁明 +1 位作者 关宗祥 罗望群 《石油炼制与化工》 CAS CSCD 北大核心 2004年第1期16-20,共5页
介绍了SBS母粒法改性沥青工业生产及产品性能 ,重点阐述了SBS母粒法改性沥青生产原料、工艺和体系配伍性 ;研究考察了改性沥青的离析性、针入度指数和旋转薄膜烘箱试验后低温延度的影响因素 ;采用优化方案 ,在工业装置生产出符合JTJ0 36... 介绍了SBS母粒法改性沥青工业生产及产品性能 ,重点阐述了SBS母粒法改性沥青生产原料、工艺和体系配伍性 ;研究考察了改性沥青的离析性、针入度指数和旋转薄膜烘箱试验后低温延度的影响因素 ;采用优化方案 ,在工业装置生产出符合JTJ0 36— 98标准的成品改性沥青。 展开更多
关键词 SBS母粒法 沥青 原料 调合性 反应温度 软化点
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Oil-Film Clutch in Soft-Start of Belt Conveyor 被引量:3
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作者 周满山 魏宸官 +1 位作者 于岩 张媛 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期142-145,共4页
The oil film clutch, which is superior in speed adjustment, is capable of being used in the belt conveyor to carry out soft start operation. According to running properties of both belt conveyor and oil film clutch... The oil film clutch, which is superior in speed adjustment, is capable of being used in the belt conveyor to carry out soft start operation. According to running properties of both belt conveyor and oil film clutch, equations that are used to decide the lubricating oil flow and the number of oil films (i.e. the number of rotating and stationary plates) are deduced theoretically. Also key parameters are provided for the design of the hydraulic system. All these together provide the theoretical basis for the soft start design of the belt conveyor and references for the application of the oil film clutch in similar fields. 展开更多
关键词 belt conveyor soft start oil film clutch lubricating theory
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初探钢琴不谐和泛音
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作者 逯嶙 《乐器》 2008年第8期18-21,共4页
英文Inharmonicity的意思是l让我们先从英文本身讲起。它是由harmonicity前加前缀“in”而组成。Harmonicity是一个名词,意思为调合性。前缀“in”表示“否定”、“与…相反”之意。所以“Inharmonicity”一词的意思为,不调和性,非... 英文Inharmonicity的意思是l让我们先从英文本身讲起。它是由harmonicity前加前缀“in”而组成。Harmonicity是一个名词,意思为调合性。前缀“in”表示“否定”、“与…相反”之意。所以“Inharmonicity”一词的意思为,不调和性,非调和性,这是直译。如要翻译成我们调律行业中的词汇,可译为不谐和的泛音,或不谐和的分音、谐音之意。下面,让我来解释, 展开更多
关键词 泛音 钢琴 调和 调合性 前缀 调律
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Mechanism of the Effect of Polyamines on the Activity of Tonoplasts of Barley Roots Under Salt Stress 被引量:9
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作者 孙诚 刘友良 章文华 《Acta Botanica Sinica》 CSCD 2002年第10期1167-1172,共6页
The seeds of barley Hordeum vulgare L. cv. Jian 4) were soaked with 0.1 mmol/L putrescine (Put) and 0.5 mmol/L spermidine (Spd), and then the seedlings were treated with 200 mmol/L NaCl. The growth rate (GR), dry matt... The seeds of barley Hordeum vulgare L. cv. Jian 4) were soaked with 0.1 mmol/L putrescine (Put) and 0.5 mmol/L spermidine (Spd), and then the seedlings were treated with 200 mmol/L NaCl. The growth rate (GR), dry matter accumulation, distribution of ions, the amount of polyamines (PAs) bound to tonoplast proteins as well as lipid composition and the activity of tonoplast vesicles isolated from roots were investigated. The results showed that soaking with Put or Spd could retard salt injury, promote GR and dry matter accumulation, and increase K+/Na+ in the roots. Compared with NaCl_treated plants, phospholipid content in root tonoplast rose by soaking with Put and Spd, while the level of galactose in lipids was decreased. Moreover, the ratio in noncovalently conjugated PA contents of (Spd+PAx (an unknown PA)) to (Put+Dap (diaminopropane)), and the total contents of covalently and noncovalently conjugated PAs were all increased. Statistical analysis indicated that the ratio of (Spd+PAx) to (Put+Dap) was significantly and positively correlated with the activities of membrane associated enzymes H+_ATPase and H+_PPase. 展开更多
关键词 BARLEY salt stress polyamines membrane lipids membrane-associated enzyme
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Research on the imaging of concrete defect based on the pulse compression technique 被引量:3
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作者 李长征 张碧星 +1 位作者 师芳芳 谢馥励 《Applied Geophysics》 SCIE CSCD 2013年第3期337-348,359,共13页
When the synthetic aperture focusing technology (SAFT) is used for the detection of the concrete, the signal-to-noise ratio (SNR) and detection depth are not satisfactory. Therefore, the application of SAFT is usu... When the synthetic aperture focusing technology (SAFT) is used for the detection of the concrete, the signal-to-noise ratio (SNR) and detection depth are not satisfactory. Therefore, the application of SAFT is usually limited. In this paper, we propose an improved SAFT technique for the detection of concrete based on the pulse compression technique used in the Radar domain. The proposed method first transmits a linear frequency modulation (LFM) signal, and then compresses the echo signal using the matched filtering method, after which a compressed signal with a narrower main lobe and higher SNR is obtained. With our improved SAFT, the compressed signals are manipulated in the imaging process and the image contrast is improved. Results show that the SNR is improved and the imaging resolution is guaranteed compared with the conventional short-pulse method. From theoretical and experimental results, we show that the proposed method can suppress noise and improve imaging contrast, and can also be used to detect multiple defects in concrete. 展开更多
关键词 Concrete defect LFM pulse compression SAFT SNR
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Tuning of the textural features and acidic properties of sulfated mesoporous lanthana-zirconia solid acid catalysts for alkenylation of diverse aromatics to their corresponding α-arylstyrenes
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作者 赵忠奎 冉金凤 +2 位作者 郭永乐 苗博元 王桂茹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1303-1313,共11页
The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9O... The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9Oδcomposites, such as the molar ratio of the template to La and Zr metal ions (Nt/m), molar ratio of ammonia to La and Zr metal ions (Na/m), hydrothermal temperature (Thydro), and hy‐drothermal time (thydro). The effect of the textural features and acidic properties on the catalytic performance of solid acid catalysts for alkenylation of p‐xylene with phenylacetylene was investi‐gated. Various characterization techniques such as N2 physisorption, X‐ray diffraction, NH3 temper‐ature‐programmed desorption, and thermogravimetric analysis were employed to reveal the rela‐tionship between the nature of catalyst and its catalytic performance. It was found that the catalytic performance significantly depended on the textural features and acidic properties, which were strongly affected by preparation conditions of the meso‐La0.1Zr0.9Oδcomposite. Appropriate acidic sites and high accessibility were required to obtain satisfactory catalytic reactions for this reaction. It was also found that the average crystallite size of t‐ZrO2 affected by the preparation conditions had significant influence on the ultrastrong acidic sites of the catalysts. The optimized SO42?/meso‐La0.1Zr0.9Oδcatalyst exhibited much superior catalytic activity and coke‐resistant stabil‐ity. Moreover, the developed SO42?/meso‐La0.1Zr0.9Oδcatalyst demonstrated excellent catalytic per‐formance for alkenylation of diverse aromatics with phenylacetylene to their correspondingα‐arylstyrenes. Combining the previously established complete regeneration of used catalysts by a facile calcination process with the improved catalytic properties, the developed SO42?/meso‐La0.1Zr0.9Oδ solid acid could be a potential catalyst for industrial production ofα‐arylstyrenes through clean and atom efficient solid‐acid‐mediated Friedel‐Crafts alkenylation of diverse aromatics with phenylacetylene. 展开更多
关键词 Mesoporous solid acid ALKENYLATION Clean synthesis Alkenyl aromatics Textural and acidic properties Tuning
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Modulation instability of dispersion-shifted fiber couplers 被引量:1
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作者 ZHOU Yan-yong JIA Wei-guo +2 位作者 HAN Ying-ming YING Chun BAO Hong-mei 《Optoelectronics Letters》 EI 2008年第4期264-268,共5页
The nonlinear coupled-mode equations are rewritten by even and odd modes.We study modulation instability(MI) of dispersion-shifted fiber couplers when either even or odd mode is launched alone by using zero-dispersion... The nonlinear coupled-mode equations are rewritten by even and odd modes.We study modulation instability(MI) of dispersion-shifted fiber couplers when either even or odd mode is launched alone by using zero-dispersion wavelength relatively long(quasi-cw) pulses.The result shows that there are new types of MI in both the normal-dispersion and the anomalous-dispersion regimes.MI is concerned with forth-order dispersion and has no relation with third-order dispersion.Quasi-cw can be changed into pulses array under certain conditions.We can extract super short pulse from this.Furthermore,the bandwidth of gain spectra widens and its strength accretes as the input power increases. 展开更多
关键词 光纤耦合器 非线耦合方程 调制不稳定 光学器件
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Differentiation of Crohn’s disease from intestinal tuberculosis in India in 2010 被引量:8
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作者 Anna Benjamin Pulimood Deepak Narayan Amarapurkar +5 位作者 Ujjala Ghoshal Mathew Phillip Cannanore Ganesh Pai Duvvur Nageshwar Reddy Birender Nagi Balakrishna Siddhartha Ramakrishna 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第4期433-443,共11页
Differentiating intestinal tuberculosis from Crohn’s disease (CD) is an important clinical challenge of considerable therapeutic significance. The problem is of greatest magnitude in countries where tuberculosis cont... Differentiating intestinal tuberculosis from Crohn’s disease (CD) is an important clinical challenge of considerable therapeutic significance. The problem is of greatest magnitude in countries where tuberculosis continues to be highly prevalent, and where the incidence of CD is increasing. The final clinical diagnosis is based on a combination of the clinical history with endoscopic studies, culture and polymerase chain reaction for Mycobacterium tuberculosis, biopsy pathology, radiological investigations and response to therapy. In a subset of patients, surgery is required and intraoperative findings with pathological study of the resected bowel provide a definitive diagnosis. Awareness of the parameters useful in distinguishing these two disorders in each of the different diagnostic modalities is crucial to accurate decision making. Newer techniques, such as capsule endoscopy, small bowel enteroscopy and immunological assays for Mycobacterium tuberculosis, have a role to play in the differentiation of intestinal tuberculosis and CD. This review presents currently available evidence regarding the usefulness and limitations of all these different modalities available for the evaluation of these two disorders. 展开更多
关键词 TUBERCULOSIS Crohn’s disease Clinical features ENDOSCOPY SEROLOGY ENTEROSCOPY HISTOLOGY RADIOLOGY Surgery Therapy
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Hybrid scheduling model and analysis of performance for switched industrial Ethernet 被引量:1
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作者 胡春华 吴敏 +1 位作者 刘国平 王四春 《Journal of Central South University of Technology》 EI 2007年第2期271-277,共7页
The fact that outburst traffic in industrial Ethemet was focused on that would bring self-similar phenomenon leading to the delay increase of the cyclical data, and a hybrid priority queue schedule model was proposed ... The fact that outburst traffic in industrial Ethemet was focused on that would bring self-similar phenomenon leading to the delay increase of the cyclical data, and a hybrid priority queue schedule model was proposed in which the outburst data was given the highest priority. Some properties of the self-similar outburst data were proved by network calculus, and its service curve scheduled by the switch was gained. And then the performance of the scheduling algorithm was obtained. The simulation results are close to those calculated by using network calculus model. Some results are of actual significance to the construction of switched industrial Ethernet. 展开更多
关键词 switched industrial Ethemet scheduling model SELF-SIMILAR network calculus
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PRINCIPLE,SOFTWARE AND EXPERIMENT OF GPS-SUPPORTED AEROTRIANGULATION 被引量:8
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作者 YUAN Xiuxiao 《Geo-Spatial Information Science》 2000年第1期24-33,共10页
In conventional aerial photogrammetry, the high accurate photogrammetric point determination is always carried out by aerotriangulation using a great deal of ground control points around the perimeter and in the cente... In conventional aerial photogrammetry, the high accurate photogrammetric point determination is always carried out by aerotriangulation using a great deal of ground control points around the perimeter and in the center of block area because the exterior orien- tation parameters of aerial photographs are unknown. A technological revolution in pho- togrammetry has taken place since Navstar global positioning system (GPS) was applied to determine the 3D coordinates of exposure station positions during the photo flight missions. GPS-supported aerotriangulation is conducted by a combined bundle adjustment for pho- togrammetric observations and the camera orientation data. In this case, the essential ground control points are replaced by GPS-determined camera positions. Recent investigations show this method is coming to the practice. We have been engaged in the theoretical studies, soft- ware development, and related experiments and production in the field since 1990. So far the abundant research achievements are obtained in terms of the theory and application. In this paper,we first derives the mathematical model of GPS-supported aerotriangulation from the geometry between camera and airborne GPS antenna, then describes briefly a software pack- age WuCAPS (Wuhan combined adjustment program system) developed newly by the au- thor,which serves the purpose of the combined bundle adjustment for photogrammetric and non-photogrammetric observations. At the end of the present work, a set of actual aerial pho- tographs,at the image scale of 1: 34 000, with airborne GPS data taken from Tianjing site, China were processed by WuCAPS. The empirical results have verified that the accuracy of the combined bundle adjustment with 4 XYZ ground control points around the corners of block area is very close to that of the conventional bundle adjustment with 3 additional pa- rameters, that leads to reduce 88% field survey and 75% production cost, and can meet the specification of topographic mapping at small or medium scale by GPS-supported aerotriangu- lation without ground control. This shows the ample applicability and the economic benefit of kinematic GPS relative positioning in high accurate photogrammetric point determination. 展开更多
关键词 GPS kinematic GPS relative positioning GPS-supported aerotriangulation combined bundle adjustment ACCURACY reliability
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Modifying the acidity of H-MOR and its catalytic carbonylation of dimethyl ether 被引量:15
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作者 Meixia Wang Shouying Huang +4 位作者 Jing Lü Zaizhe Cheng Ying Li Shengping Wang Xinbin Ma 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1530-1538,共9页
Among the reactions catalyzed by zeolites there are some that exhibit high selectivity due to the spatial confinement effect of the zeolite framework.Tailoring the acidity,particularly the distribution and location of... Among the reactions catalyzed by zeolites there are some that exhibit high selectivity due to the spatial confinement effect of the zeolite framework.Tailoring the acidity,particularly the distribution and location of the Bronsted acid sites in the zeolite is effective for making it a better catalyst for these reactions.We prepared a series of H-mordenite(H-MOR) samples by varying the composition of the sol-gel,using different structure directing agents and post-treatment.NH3-TPD and IR characterization of adsorbed pyridine were employed to determine the amount of Bronsted acid sites in the 8-membered ring and 12-membered ring channels.It was shown that controlled synthesis was a promising approach to improve the concentration of Bronsted acid sites in MOR,even with a low Al content.Using an appropriate composition of Si and Al in the sol-gel favored a higher proportion of Bronsted acid sites in the 8-membered ring channels.HMI as a structure-direct agent gave an obvious enrichment of Bronsted acid sites in the 8-membered ring.Carbonylation of dimethyl ether was used as a probe reaction to examine the modification of the acid properties,especially the Bronsted acid sites in the 8-membered ring channels.There was a linear relationship between methyl acetate formation and the number of Bronsted acid sites in the 8-membered ring channels,demonstrating the successful modification of acid properties.Our results provide information for the rational design and modification of zeolites with spatial constraints. 展开更多
关键词 Zeolite H-MORDENITE Modification of acidity Hydrothermal synthesis Structure-direct agent Post treatment Carbonylation of dimethyl ether
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Arterial traffic signal coordination model considering buses and social vehicles 被引量:5
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作者 Zhang Weihua Li Jun Ding Heng 《Journal of Southeast University(English Edition)》 EI CAS 2020年第2期206-212,共7页
Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum... Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum bandwidth is proposed.By using the pre-set parameters of a common cycle,green/red duration and known parameters of bus dwell time distribution,link length and vehicle speed and solving the mixed-integer-linear programming and optimizing the signal offsets,the model obtains the signal control parameters of the green bands both of social vehicles and buses.Finally,taking Wangjiang Road in Hefei as an example,simulation and evaluation are carried out by VISSIM.The results show that the new model has 15.2%and 13.2%reduction in average person delay and number of stops,respectively,compared with the traditional coordinated control method. 展开更多
关键词 arterial coordination control buses coordination maximum bandwidth mixed-integer-linear programming
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Simultaneous Optimization of Synthesis and Scheduling of Cleaning in Flexible Heat Exchanger Networks 被引量:9
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作者 肖丰 都健 +2 位作者 刘琳琳 栾国颜 姚平经 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第3期402-411,共10页
A novel methodology is presented for simultaneously optimizing synthesis and cleaning schedule of flexible heat exchanger network(HEN)by genetic/simulated annealing algorithms(GA/SA).Through taking into account the ef... A novel methodology is presented for simultaneously optimizing synthesis and cleaning schedule of flexible heat exchanger network(HEN)by genetic/simulated annealing algorithms(GA/SA).Through taking into account the effect of fouling process on optimal network topology,a preliminary network structure possessing two-fold oversynthesis is obtained by means of pseudo-temperature enthalpy(T-H)diagram approach prior to simultaneous optimization.Thus,the computational complexity of this problem classified as NP(Non-deterministic Polynomial)-complete can be significantly reduced.The promising matches resulting from preliminary synthesis stage are further optimized in parallel with their heat exchange areas and cleaning schedule.In addition,a novel continu- ous time representation is introduced to subdivide the given time horizon into several variable-size intervals according to operating periods of heat exchangers,and then flexible HEN synthesis can be implemented in dynamic manner.A numerical example is provided to demonstrate that the presented strategy is feasible to decrease the total annual cost(TAC)and further improve network flexibility,but even more important,it may be applied to solve large-scale flexible HEN synthesis problems. 展开更多
关键词 flexible heat-exchanger network SYNTHESIS cleaning schedule continuous time representation simultaneous optimization
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Some Dynamic and Combinatorial Properties of One Parameter Families of Unimodal Maps with Monotonicity
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作者 John Taylor 《Journal of Mathematics and System Science》 2013年第6期301-308,共8页
It is known that certain one parameter families of unimodal maps of the interval have a topological universality with regard to their dynamic behavior [ 1, 2]. As a parameter is smoothly increased, a fascinating varie... It is known that certain one parameter families of unimodal maps of the interval have a topological universality with regard to their dynamic behavior [ 1, 2]. As a parameter is smoothly increased, a fascinating variety of dynamic behaviors are produced. For some families the behaviors are monotonic in the parameter, while in others they are not [3]. The question is what sort of conditions on a one parameter family will ensure this monotonicity of the behavior with the parameter? The answer is unknown and will not be given here. What we do instead is to investigate certain geometric-dynamic-combinatorial consequences of assuming that the family has this monotonicity. Specifically, using tools of symbolic dynamics, state space is "course grained" with a finite alphabet. We decompose a non-invertible map into nonlinear but invertible pieces. From these invertible pieces, we form inverse maps via composition along words. Equations of motion are developed for both forward and inverse orbits (in both the variables of state space and the parameter), and an equation relating forward and inverse motions at fix-points is exhibited. Finally, we deduce a list of conditions, each of which is equivalent to monotone behavior. One of these conditions states that simple parity characteristics of words correspond to definite dynamics near fixed-points and vice versa. 展开更多
关键词 One parameter family unimodal map kneading theory connection equation.
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Reliability of flip-chip bonded RFID die using anisotropic conductive paste hybrid material 被引量:1
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作者 Jun-Sik LEE Jun-Ki KIM +2 位作者 Mok-Soon KIM Namhyun KANG Jong-Hyun LEE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第A01期175-181,共7页
A reliability of flip-chip bonded die as a function of anisotropic conductive paste (ACP) hybrid materials, bonding conditions, and antenna pattern materials was investigated during the assembly of radio frequency ide... A reliability of flip-chip bonded die as a function of anisotropic conductive paste (ACP) hybrid materials, bonding conditions, and antenna pattern materials was investigated during the assembly of radio frequency identification(RFID) inlay. The optimization condition for flip-chip bonding was determined from the behavior of bonding strength. Under the optimized condition, the shear strength for the antenna printed with paste-type Ag ink was larger than that for Cu antenna. Furthermore, an identification distance was varied from the antenna materials. Comparing with the Ag antenna pattern, the as-bonded die on Cu antenna showed a larger distance of identification. However, the long-term reliability of inlay using the Cu antenna was decreased significantly as a function of aging time at room temperature because of the bended shape of Cu antenna formed during the flip-chip bonding process. 展开更多
关键词 RFID inlay ACP flip-chip bonding process RELIABILITY
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Microstructure and mechanical properties of melt-conditioned high-pressure die-cast Mg-Al-Ca alloy 被引量:1
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作者 梁松茂 张华伟 +3 位作者 夏明许 陈荣石 韩恩厚 FAN Zhong-yun 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第7期1205-1211,共7页
A new shape casting process,melt-conditioned high-pressure die-casting(MC-HPDC) was developed.In this process,liquid metal was conditioned under intensively forced convection provided by melt conditioning with advance... A new shape casting process,melt-conditioned high-pressure die-casting(MC-HPDC) was developed.In this process,liquid metal was conditioned under intensively forced convection provided by melt conditioning with advanced shear technology(MCAST) unit before being transferred to a conventional cold chamber high-pressure die-casting(HPDC) machine for shape casting. The effect of melt conditioning was investigated,which was carried out both above and below the liquidus of the alloy,on the microstructure and properties of a Mg-Al-Ca alloy(AZ91D+2%Ca(mass fraction) ,named as AZX912) .The results show that many coarse externally-solidified crystals(ESCs) can be observed in the centre of conventional HPDC samples,and hot tearing occurs at the inter-dendritic region because of the lack of feeding.With the melting conditioning,the MC-HPDC samples not only have considerably refined size of ESCs but also have significantly reduced cast defects,thus provide superior mechanical properties to conventional HPDC castings.The solidification behaviour of the alloy under different processing routes was also discussed. 展开更多
关键词 Mg alloy Mg-Al-Ca alloy melt conditioning grain refinement SOLIDIFICATION die casting
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Application of hybrid robust three-axis attitude control approach to overactuated spacecraft——A quaternion based model 被引量:2
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作者 A.H.Mazinan 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第7期1740-1753,共14页
A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that th... A novel hybrid robust three-axis attitude control approach, namely HRTAC, is considered along with the well-known developments in the area of space systems, since there is a consensus among the related experts that the new insights may be taken into account as decision points to outperform the available materials. It is to note that the traditional control approaches may generally be upgraded, as long as a number of modifications are made with respect to state-of-the-art, in order to propose high-precision outcomes. Regarding the investigated issues, the robust sliding mode finite-time control approach is first designed to handle three-axis angular rates in the inner control loop, which consists of the pulse width pulse frequency modulations in line with the control allocation scheme and the system dynamics. The main subject to employ these modulations that is realizing in association with the control allocation scheme is to be able to handle a class of overactuated systems, in particular. The proportional derivative based linear quadratic regulator approach is then designed to handle three-axis rotational angles in the outer control loop, which consists of the system kinematics that is correspondingly concentrated to deal with the quaternion based model. The utilization of the linear and its nonlinear terms, simultaneously, are taken into real consideration as the research motivation, while the performance results are of the significance as the improved version in comparison with the recent investigated outcomes. Subsequently, there is a stability analysis to verify and guarantee the closed loop system performance in coping with the whole of nominal referenced commands. At the end, the effectiveness of the approach considered here is highlighted in line with a number of potential recent benchmarks. 展开更多
关键词 three-axis angular rates and rotations sliding mode finite-time control approach proportional derivative based linearquadratic regulator approach dynamics and kinematics of overactuated spacecraft
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Selective Synthesis of Different-Sized Gold Nanoclusters through HCI-Etching and-Growth Effect
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作者 Ting Huang Zhi-hu Sun Guo-qiang Pan 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第2期223-228,246,共7页
Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 ... Controllable syntheses of different-sized gold nanoclusters are of great significance for their fundamental science and practical applications. In this work, we achieve the controllable and selective syntheses of Au7 and Au13 clusters through adding HCl to the traditional Aull synthetic route at different reaction time. Time-dependent mass spectra and UV- Vis spectra were ernployed to monitor these two HCl-directed processes, and revealed the distinct roles of HCl as an etchant or a growth prornotor, respectively. Furthermore, parallel experiments on independent synthetic routes involving only non-chlorine H+ (acetic acid) or Cl (tetraethy larnrnoniurn chloride) instead of HCl were perforrned, which illustrated the main role of H^+-etching and Cl^ -assisted growth in HCl-directed cluster synthetic routes. We propose the HCl-etching is mainly achieved via the H+ action to break the Au(I)-PPh3 part of clusters, while the HCl-prornoted growth is realized via the attachment of Au-Cl species to the pre-forrned clusters. 展开更多
关键词 Selective synthesis Route control HC1 Etching and growth effects
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Acute lung injury and acute respiratory distress syndrome: experimental and clinical investigations 被引量:7
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作者 Hsing I Chen 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2011年第1期44-54,共11页
Acute lung injury (ALl) or acute respiratory distress syndrome (ARDS) can be associated with various disorders. Recent investigation has involved clinical studies in collaboration with clinical investigators and p... Acute lung injury (ALl) or acute respiratory distress syndrome (ARDS) can be associated with various disorders. Recent investigation has involved clinical studies in collaboration with clinical investigators and pathologists on the pathogenetic mechanisms of ALl or ARDS caused by various disorders. This literature review includes a brief historical retrospective of ALI/ARDS, the neurogenic pulmonary edema due to head injury, the long-term experimental studies and clinical investigations from our laboratory, the detrimental role of NO, the risk factors, and the possible pathogenetic mechanisms as well as therapeutic regimen for ALI/ARDS. 展开更多
关键词 acute lung injury acute respiratory distress syndrome neurogenic pulmonary edema nitric oxide free radicals CYTOKINES
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Effects of Pressure Stress Work and Viscous Dissipation in Mixed Convection Flow Along a Vertical Flat Plate
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作者 A.S. Bhuiyan J. M. Alam M. R. Biswas 《Journal of Mathematics and System Science》 2013年第3期115-121,共7页
The Effects of pressure stress work and viscous dissipation in mixed convection flow along a vertical fiat plate have been investigated. The results are obtained by transforming the governing system of boundary layer ... The Effects of pressure stress work and viscous dissipation in mixed convection flow along a vertical fiat plate have been investigated. The results are obtained by transforming the governing system of boundary layer equations into a system of non-dimensional equations and by applying implicit finite difference method together with Newton's linearization approximation. Numerical results for different values of pressure stress work parameter, viscous dissipation parameter and Prandtl number have been obtained. The velocity profiles, temperature distributions, skin friction co-efficient and the rate of heat transfer have been presented graphically for the effects of the aforementioned parameters. 展开更多
关键词 Mixed convection viscous dissipation pressure stress work.
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