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超导环回旋加速器
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作者 方正 《等离子体应用技术快报》 2000年第6期23-26,共4页
关键词 超导环回旋加速器 结构 重离子体
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Dyeing Behavior of Yak Hair Fiber Treated with Microwave Low Temperature Plasma 被引量:2
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作者 马晓光 张晓林 顾振亚 《Journal of Donghua University(English Edition)》 EI CAS 2006年第1期27-31,共5页
The scales on the surface of yak hair fiber act as barriers during the dyeing process. In order to solve the scale problem and to improve the dyeability of yak hair, yak hair fiber was treated by microwave low tempera... The scales on the surface of yak hair fiber act as barriers during the dyeing process. In order to solve the scale problem and to improve the dyeability of yak hair, yak hair fiber was treated by microwave low temperature plasma (MLTP) in this study. The weight loss and the dyeing properties of the yak hair fiber modified by MLTP were investigated. Scanning Electron Microscopy (SEM) photographs were taken to observe the changes in the surface shape of yak hair fiber before and after treatment. Results showed that after MLTP treatment, the scale structure of yak hair was weakened and damaged greatly and the noticeable changes on the surface shape took place. At the same time, a significant improvement in dyeing properties of yak hair fiber was exhibited. 展开更多
关键词 MICROWAVE low temperature PLASMA yak hair weight loss dyeing properties.
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Microbial Remediation of Heavy Metal(loid)Contaminated Soil: A Review 被引量:11
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作者 Zhiqiang YU 《Agricultural Science & Technology》 CAS 2016年第1期85-91,共7页
Because of the rapid development of industrial processes, increased urban pollution and agricultural chemicals applied in recent years, heavy metal(loid) pollution in soil has been very serious, and there is an urgent... Because of the rapid development of industrial processes, increased urban pollution and agricultural chemicals applied in recent years, heavy metal(loid) pollution in soil has been very serious, and there is an urgent need for fast and efficient removal of heavy metal(loid) pollution. Currently, environmental microorganisms are always used to perform biological alteration or improvement of soils and sewage. Using functional microorganisms that are resistant to toxic heavy metal(loid) ions for alteration and transformation of heavy metal(loid)s in ionic form is an effective measure for microbial remediation of heavy metal(loid)contaminated soil. This paper reviewed the microbial remediation mechanism of heavy metal(loid) contaminated soils, and the approaches for breeding bacteria those can be used for highly efficient removal of heavy metal(loid)s, as well as the application examples of microbial remediation and transformation of heavy metal(loid) contaminated soil, and finally described the future trends and further research work of heavy metal(loid) contaminated soils by microbial remediation. 展开更多
关键词 Heavy metal(loid)s Microbial remediation Breeding approaches Microbial metabolic activities
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Experimental assessment of a plasma-catalyst hybrid reformer for hydrogen production via partial oxidation of dimethyl ether
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作者 宋凌珺 李兴虎 《Journal of Central South University》 SCIE EI CAS 2014年第5期1956-1960,共5页
In this work,hydrogen is produced from partial oxidation reforming of dimethyl ether (DME) by a plasma-catalyst hybrid reformer under atmospheric pressure.The plasma-catalyst hybrid reformer which includes both plas... In this work,hydrogen is produced from partial oxidation reforming of dimethyl ether (DME) by a plasma-catalyst hybrid reformer under atmospheric pressure.The plasma-catalyst hybrid reformer which includes both plasma and catalyst reactors is designed.A spark discharge is used as a non-equilibrium plasma source,and it is used to ionize the mixture of DME and air.The performances of the reformer are characterized experimentally in terms of gas concentrations,hydrogen yield,DME conversion ratio,and specific energy consumption.The effects of discharge frequency,reaction temperature,air-to-DME ratio and space velocity are investigated.The experimental results show that the plasma-catalyst hybrid reformer enhances hydrogen yield when reaction temperature drops below 620 ℃.At 450 ℃,hydrogen yield of hybrid reforming is almost three times that of catalyst reforming.When space velocity is 510 h-1,hydrogen yield is 67.7%,and specific energy consumption is 12.2 k J/L-H2. 展开更多
关键词 spark discharge plasma HYBRID REFORMING hydrogen production dimethyl ether
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Steam Reforming of Dimethyl Ether by Gliding Arc Gas Discharge Plasma for Hydrogen Production
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作者 王保伟 孙启梅 +2 位作者 吕一军 杨美琳 闫文娟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第1期104-112,共9页
Gliding arc gas discharge plasma was used for the generation of hydrogen from steam reforming of dimethyl ether(DME).A systemic procedure was employed to determine the suitable experimental conditions.It was found tha... Gliding arc gas discharge plasma was used for the generation of hydrogen from steam reforming of dimethyl ether(DME).A systemic procedure was employed to determine the suitable experimental conditions.It was found that DME conversion first increased up to the maximum and then decreased slightly with the increase of added water and air.The increase of total feed gas flow rate resulted in the decrease of DME conversion and hydrogen yield,but hydrogen energy consumption dropped down to the lowest as total feed gas flow rate increased to76 ml·min 1.Larger electrode gap and higher discharge voltage were advantageous.Electrode shape had an important effect on the conversion of DME and production of H2.Among the five electrodes,electrode 2#with valid length of 55 mm and the radian of 34 degrees of the top electrode section was the best option,which enhanced obviously the conversion of DME. 展开更多
关键词 dimethyl ether steam reforming hydrogen production gliding arc gas discharge
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Orlistat-lnduced Modulation of Plasma Metabolites Independent of Weight Loss in Overweight Females
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作者 Thiago I. B. Lopes Lucas G. Martins +2 位作者 Sabrina Nagassaki Bruno Geloneze Anita Jocelyne Marsaioli 《Journal of Chemistry and Chemical Engineering》 2013年第6期547-555,共9页
Orlistat-induced weight loss results in amelioration in several comorbidities including obesity-related dyslipidemia. The aim of the present study was to characterize the changes in the blood plasma metabolic profile ... Orlistat-induced weight loss results in amelioration in several comorbidities including obesity-related dyslipidemia. The aim of the present study was to characterize the changes in the blood plasma metabolic profile from overweight women treated with Orlistat, a lipase inhibitor. A metabonomic approach employing LHNMR was applied to the access metabolic profile in lean and overweight women after a 120 day treatment with 120 mg of Orlistat three times daily. Twenty overweight women (BMI: 32.8 ± 2.9 kg/m2) were evaluated before and after Orlistat treatment and seven normal weight women (BMh 21.8 ± 1.4 kg/m2) were taken as control. After 120 days of treatment with Orlistat, no significant weight changes were observed. However, Orlistat-induced metabolic changes in overweight subjects decreased the profile differences between lean and obese individuals, independent of weight loss. These were associated to decreasing levels of lactate and calcium. Higher levels of lactate, alanine and lipids from overweight subjects were detected in comparison to lean individuals. These results show that a lipase inhibitor shifts the metabolic profile of overweight subjects towards normality, independent of weight loss. 展开更多
关键词 tH NMR METABONOMICS LACTATE EDTA calcium.
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Analysis of bulked segregants to identify molecular markers linked with cocoon weight and cocoon shell weight in the silkworm Bombyx mori L
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作者 SateeshKumar 徐孟奎 +2 位作者 陈玉银 Ponnuvel,K.M Datta,R.K 《Journal of Zhejiang University Science》 CSCD 2002年第3期348-354,共7页
Two silkworm strains viz, B20 A (high cocoon shell ratio) and C.Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygosis. Both bulked segregant analysis(BSA) and near isogenic line... Two silkworm strains viz, B20 A (high cocoon shell ratio) and C.Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygosis. Both bulked segregant analysis(BSA) and near isogenic lines (NIL) studies were done to identify the RFLP markers closely linked to cocoon shell parameters. Three hundred and fifty two random clones were identified as the low copy number sequence and used for identification of Restriction Fragment Length Polymorphic (RFLP) marker linked to cocoon weight and cocoon shell character. In the bulk segregant analysis, DNA from the parents (B20 A, C.Nichi), F 1 and F 2 progeny of high shell ratio (HSR) and low shell ratio (LSR) were screened for hybridization with the random clones. Polymorphic banding pattern achieved through southern hybridization with different probes indicated the probable correlation of polymorphism with high and low cocoon shell character which are possible landmarks in identifying the putative marker(s) for the cocoon shell character. Out of the 100 probes tried with parents, F 1, F 2 and their bulks, 10 probes were found to be closely linked to cocoon shell characters. 展开更多
关键词 Restriction fragment length polymorphic (RFLP) Molecular marker Bombyx mori L Shell ratio Bulked segregant analysis(BSA) Near isogenic lines
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Bioavailability of heavy metals in soil of the Tieguanyin tea garden, southeastern China 被引量:2
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作者 Jingwei Sun Ruilian Yu +3 位作者 Gongren Hu Songhe Jiang Yunfeng Zhang Xiaoming Wang 《Acta Geochimica》 EI CAS CSCD 2017年第3期519-524,共6页
The bioavailability of 22 heavy metals was investigated at 19 sampling sites in Tieguanyin tea garden in Anxi County,Fujian Province,southeastern China.Heavy metal concentrations were determined by inductively coupled... The bioavailability of 22 heavy metals was investigated at 19 sampling sites in Tieguanyin tea garden in Anxi County,Fujian Province,southeastern China.Heavy metal concentrations were determined by inductively coupled plasma-mass spectrometry(ICP-MS)and evaluated by geo-accumulation index(I_(geo)).Dilute nitric acid extraction was used to evaluate biological activity.Cu,Pb,and Cd were highly bioavailable and most easily absorbed by tea trees.Heavy metal bioavailability in the surface soil was as the ratio of the effective state to the total amount.Cd had the highest I_(geo)values,and the respective samples and sites were classified as moderately/strongly contaminated.Cd element is considered the main factor of heavy metal pollution in the tea garden in Anxi.The other heavy metals studied were present in lower concentrations;thus,the samples were classified as uncontaminated or slightly contaminated. 展开更多
关键词 Geo-accumulation index Tieguanyin tea garden Heavy metals BIOAVAILABILITY Dilute nitric acid extraction Southeastern China
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An Explanation of a Phenomenon in Relativistic Heavy-Ion Collisions
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作者 陈小凡 杨学栋 +2 位作者 陈志来 孙芳魁 苏润洲 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期640-642,共3页
The multi-source pion interferometry in relativistic heavy-ion collisions is presented and two-source models for hadron gas and hadron gas plus quark-gluon plasma are proposed. The models can resolve the HBT puzzle. F... The multi-source pion interferometry in relativistic heavy-ion collisions is presented and two-source models for hadron gas and hadron gas plus quark-gluon plasma are proposed. The models can resolve the HBT puzzle. For the same q and different direction of q, the two-pion correlation functions show characteristic oscillation behaviors, which may be used to distinguish the two-source models. Our research also showes that the multi-source pion correlations can resolve the HBT puzzle. 展开更多
关键词 multi-source pion interferometry HBT puzzle relativistic heavy-ion collisions
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Composition of Pig Manures and Wastewaters under the Gan Qing Fen System in China 被引量:1
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作者 R. Mendoza-Huaitalla E. Gallmann +2 位作者 K. Zheng X. J. Liu E. Hartung 《Journal of Agricultural Science and Technology(A)》 2011年第4X期514-518,共5页
A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2... A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2009. Samples were collected once a week based on the pig production cycle, namely gestation, farrowing, weaning and fattening. Analysis of nutrients and heavy metals were determined by means of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP). Total Nitrogen (TN) was determined by the Kjeldahl method. The main results showed that pig manures were characterized by high nutrients and heavy metals contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manure management system. Further, piggery wastewaters were characterized by very low concentrations of nutrients and heavy metals as result of their dilution with flushing water mainly used for cleaning the pigsties. Manure and wastewaters samples from weaning pigs contained the highest concentrations of nutrients and heavy metals that could be due to high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manures in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manures but the use of flushing water should be reduced as it can lead to further environmental pollution. 展开更多
关键词 China gan qing fen MANURE WASTEWATER pig farm.
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A Novel Method for Producing Hydrogen from a Hydrocarbon Liquid Using Microwave In-liquid Plasma
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作者 Andi Amijoyo Mochtar Shinfuku Nomura +4 位作者 Shinobu Mukasa Hiromichi Toyota Kohji Kawamukai Kojiro Uegaito Fadhli Syahrial 《Journal of Energy and Power Engineering》 2016年第6期335-342,共8页
The in-liquid plasma method is a technology in which plasma of several thousand degrees Kelvin is generated within bubbles in a liquid. The purpose of this study is to enhance the hydrogen production rate from waste o... The in-liquid plasma method is a technology in which plasma of several thousand degrees Kelvin is generated within bubbles in a liquid. The purpose of this study is to enhance the hydrogen production rate from waste oils by using in-liquid plasma. Two types of microwave in-liquid plasma apparatus are adopted for hydrogen production. One is a conventional MW (microwave) oven, the other is a microwave generator with a waveguide to apply the in-liquid plasma steam reforming method in n-dodecane. The produced gas is 58%-90% hydrogen in these methods. The hydrogen production rate is improved by stabilization of the bubble growth. The gas production rate by plasma feeding steam in n-dodecane is 1.4 times higher than that without feeding steam. 展开更多
关键词 In-liquid plasma HYDROGEN MICROWAVE N-DODECANE steam reforming waste oils.
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Modeling of Track Formation in Semiconductors Irradiated with Swift Heavy Ions
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作者 Soraya Kadid Ali Meftah 《Journal of Physical Science and Application》 2012年第8期269-273,共5页
The interaction of the heavy charged particles, of energy higher than a few MeV/amu with semiconductor single crystals can lead to the structural modification of their physical properties and participate at the creati... The interaction of the heavy charged particles, of energy higher than a few MeV/amu with semiconductor single crystals can lead to the structural modification of their physical properties and participate at the creation of the defects which are called latent tracks. Several models were tested for explaining the track formation in semiconductors irradiated with swift heavy ions, one of them is the thermal spike model. This work shows that the experimental data obtained in semiconductors, in our case in InP irradiated with swift heavy ions can be described on the basis of the thermal spike model. The experimental results obtained on InP have allowed the parameters of this model to be understood. The only free parameter is the electron-phonon coupling constant g which is unknown in InP This model allows the evolution of track radii to be found as a function of electronic stopping power (dE/dx)e for different beam energies. For InP a good agreement is observed between calculated track radii and experimental ones on one hand, and on the other hand between calculated and experimental threshold value of electronic stopping power. This allows determining the electron-phonon coupling value for InP to be equal 0.9 × 10%11 Wcm-3K-land the (dE/dx)e threshold for latent track formation in InP equal 27 + 3 keV/nm for ion energies ranging from 0.4-10 MeV/amu. 展开更多
关键词 SEMICONDUCTORS swift heavy ions ion tracks thermal spike model.
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Upgrading of a Heavy Ion 1MeV ISR RFQ Accelerator 被引量:1
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作者 张萌 陆元荣 +14 位作者 彭士香 朱昆 颜学庆 高淑丽 王智 郭之虞 赵捷 方家驯 李纬国 郭菊芳 袁忠喜 宋执中 于金祥 于茂林 陈佳洱 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第z1期262-264,共3页
This paper presents new beam test results for O^+ beam on a high current Integral Split Ring Radio Frequency Quadruple(ISR RFQ)accelerator.After the upgrading,a new designed 2.45GHz O^+ ECR Ion Source can provide a be... This paper presents new beam test results for O^+ beam on a high current Integral Split Ring Radio Frequency Quadruple(ISR RFQ)accelerator.After the upgrading,a new designed 2.45GHz O^+ ECR Ion Source can provide a beam with macro-puise peak current of 4mA at the injection point behind a 15ram diaphragm,whose O^+ factor is 60%—80% varied with gas flow rate and the normalized rms emittance is less than 0.15πmm·mrad.The accelerated O^+ beam current goes up to 2mA with the transmission of about 80% at 45kW RF power with duty factor 1/6(pulse duration of 1ms and repetition frequency of 166Hz).The upgraded RF power system includes low level RF pulse modulation amplifier,AGC,3W and 20W preamplifiers,1kW driver and 30kW final amplifier,which can output nearly 50kW in pulsed mode.The vacuum has been improved,too.The upgraded 1MeV ISR RFQ can be used as the beam injector of a new designed SFRFQ accelerating system,which is under the construction at Peking University. 展开更多
关键词 integral split ring RFQ UPGRADE RF power system
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A new class of ion-ion interaction: Z-bond 被引量:4
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作者 Kun Dong Suojiang Zhang Qian Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第3期495-500,共6页
The hydrogen-bond interactions in ionic liquids have been simply described by the conventional hydrogen-bond model of A–H···B. Coupling with the strong electrostatic force, however, hydrogen bond betwe... The hydrogen-bond interactions in ionic liquids have been simply described by the conventional hydrogen-bond model of A–H···B. Coupling with the strong electrostatic force, however, hydrogen bond between the cation and anion shows particular features in the geometric, energetic, electronic, and dynamic aspects, which is inherently different from that of the conventional hydrogen bond. A general model could be expressed as +[A–H···B]-, in which A and B represent heavy atoms and "+" and "–" represent the charges of the cation containing A atom and anion containing B atom, respectively. Because the structure shows a "zig-zag" motif, this coupling interaction is defined here as the Z-bond. The new model could be generally used to describe the interactions in ionic liquids, as well as bio-systems involved in ions, ionic reaction, and ionic materials. 展开更多
关键词 ionic liquid INTERACTION hydrogen bond Z-bond
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Magnetic reconnection driven by intense lasers 被引量:1
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作者 Jiayong Zhong Xiaoxia Yuan +2 位作者 Bo Han Wei Sun Yongli Ping 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2018年第3期85-101,共17页
Laser-driven magnetic reconnection(LDMR) occurring with self-generated B fields has been experimentally and theoretically studied extensively, where strong B fields of more than megagauss are spontaneously generated i... Laser-driven magnetic reconnection(LDMR) occurring with self-generated B fields has been experimentally and theoretically studied extensively, where strong B fields of more than megagauss are spontaneously generated in highpower laser–plasma interactions, which are located on the target surface and produced by non-parallel temperature and density gradients of expanding plasmas. For properties of the short-lived and strong B fields in laser plasmas, LDMR opened up a new territory in a parameter regime that has never been exploited before. Here we review the recent results of LDMR taking place in both high and low plasma beta environments. We aim to understand the basic physics processes of magnetic reconnection, such as particle accelerations, scale of the diffusion region, and guide field effects. Some applications of experimental results are also given especially for space and solar plasmas. 展开更多
关键词 high energy density physics laser plasmas interaction plasmas astrophysics
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Band structure reconstruction across nematic order in high quality FeSe single crystal as revealed by optical spectroscopy study 被引量:2
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作者 Haipeng Wang Zirong Ye +1 位作者 Yan Zhang Nanlin Wang 《Science Bulletin》 SCIE EI CAS CSCD 2016年第14期1126-1131,共6页
We perform an in-plane optical spectroscopy measurement on high quality FeSe single crystals grown by a vapor transport technique. Below the structural transition at Ts - 90 K, the reflectivity spectrum clearly shows ... We perform an in-plane optical spectroscopy measurement on high quality FeSe single crystals grown by a vapor transport technique. Below the structural transition at Ts - 90 K, the reflectivity spectrum clearly shows a gradual suppression around 400 cm-1 and the conductivity spectrum shows a peak at higher frequency. The energy scale of this gap-like feature is comparable to the width of the band splitting observed by ARPES. The low-frequency conductivity consists of two Drude components and the overall plasma frequency is smaller than that of the FeAs based compounds, suggesting a lower cartier density or stronger correlation effect. The plasma frequency becomes even smaller below Ts which agrees with the very small Fermi energy estimated by other experiments. Similar to iron pnictides, a clear temperature-induced spectral weight transfer is observed for FeSe, being indicative of strong correlation effect. 展开更多
关键词 Iron-based superconductor OPTICALSPECTROSCOPY Nematic phase Band reconstruction
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Temperature of Heavy Fragments in Heavy-Ion Collisions 被引量:1
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作者 马春旺 王闪闪 +4 位作者 普洁 陈丽 杨杰 杨佳斌 郭美婷 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第1期95-98,共4页
The heavy fragments in heavy-ion collisions are finally formed after the hot prefragments undergo sequential decay, of whom the temperature should be much lower than that of prefragments. Using the double ratio (DR)... The heavy fragments in heavy-ion collisions are finally formed after the hot prefragments undergo sequential decay, of whom the temperature should be much lower than that of prefragments. Using the double ratio (DR) method, the isotopic thermometer (Tiso ) for heavy fragment is constructed using the yield of heavy isotopes. Tiso of heavy fragment is obtained by analyzing the measured data in the 1A GeV 124'136Xe and 140A MeV 48Ca/64Ni reactions. Result shows that Tiso varies from 0.5 MeV to 10 MeV. But most Tiso is around 1 4- 0.5 MeV, which is much lower than temperature of light particles. Result also indicates that the difference between Tiso of heavy fragments in different reactions is very small, and ~o is independent on the size of the reaction system, the incident energy and the neutron-richness of the projectile. 展开更多
关键词 TEMPERATURE double ratio method heavy fragment
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Characteristic of rich-mixture ignition kernel driven by nanosecond repetitive pulsed discharge 被引量:1
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作者 LIN BingXuan WU Yun +4 位作者 LI YiWen JIA Min ZONG HaoHua DING Jian LI YingHong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第1期109-116,共8页
Plasma-assisted ignition is a promising technology to improve engine performance. Nanosecond repetitive pulsed discharge is widely used in plasma-assisted ignition owing to its chemical activations and thermal and hyd... Plasma-assisted ignition is a promising technology to improve engine performance. Nanosecond repetitive pulsed discharge is widely used in plasma-assisted ignition owing to its chemical activations and thermal and hydrodynamic expansions. However, the influence of ultrafast heating and hydrodynamic effects on the development of the rich-mixture ignition kernel is largely unknown. The present study aims to illustrate these effects using electrical and schlieren measurement. The number and the frequency of discharge pulses are exactly controlled to establish the relationship among the discharge energy, frequency, and rich-mixture ignition-kernel characteristics. The evolution of the ignition kernel in the early stage is mainly dominated by the discharge energy and frequency, i.e., a greater energy and a higher frequency yield a larger ignition kernel. Moreover, the influence of both the energy and frequency on the ignition kernel gradually disappears as the ignition kernel develops. According to the experimental data and theoretical analysis, the calculated laminar burning velocity is 0.319 m/s with a Markstein length of 13.43±0.11 cm when the voltage is 5.9 k V, the frequency is 3 k Hz, and the equivalence ratio is 1.3. This result indicates that the rich-mixture flame is stable in the early stage of ignition. 展开更多
关键词 plasma-assisted ignition NRP discharge rich-mixture ignition kernel laminar burning velocity markstein length
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A Derivation of the Entropy-Based Relativistic Smoothed Particle Hydrodynamics by Variational Principle
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作者 Philipe Mota Wei-Xian Chen Wei-Liang Qian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第9期382-386,共5页
In this work, a second order smoothed particle hydrodynamics is derived for the study of relativistic heavy ion collisions. The hydrodynamical equation of motion is formulated in terms of the variational principle. In... In this work, a second order smoothed particle hydrodynamics is derived for the study of relativistic heavy ion collisions. The hydrodynamical equation of motion is formulated in terms of the variational principle. In order to describe the fluid of high energy density but of low baryon density, the entropy is taken as the base quantity for the interpolation. The smoothed particle hydrodynamics algorithm employed in this study is of the second order, which guarantees better particle consistency. Furthermore, it is shown that the variational principle preserves the translational invariance of the system, and therefore improves the accuracy of the method. A brief discussion on the potential implications of the model in heavy ion physics as well as in general relativity are also presented. 展开更多
关键词 HYDRODYNAMICS SPH method variational principle
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Crescent aromatic oligothioamides as highly selective receptors for copper(Ⅱ) ion
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作者 HE LuTao JIANG Qian +6 位作者 GAO RongZhao YANG XinShi FENG Wen LUO ShunZhong YANG YanQiu YANG Liang YUAN LiHua 《Science China Chemistry》 SCIE EI CAS 2014年第9期1246-1256,共11页
A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using L... A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using Lawesson's reagent. The X-ray structure of a trimeric analogue(13) revealed the presence of intramolecular three-center hydrogen bonds that are responsible for the rigidification of the molecular backbone. The extraction by these novel receptors toward some representative heavy metal cations(Zn2+, Cd2+, Co2+, Ni2+, Pb2+, and Cu2+) and alkali and alkaline earth metal cations(Li+, Na+, K+, Rb+, Cs+, Ca2+, and Sr2+) demonstrated high efficiency(83.5%–96.4%) and superior selectivity for Cu2+ over other selected metal cations. Particularly, the extractability was correlated to both the number of sulfur atoms and orientation of thiocarbonyl groups as revealed in the order: 6 > 4 > 18 > 15. This is in stark contrast to the oligoamides that only gave much lower extractability(5.9%–16.4%), suggestive of the importance of replacement of carbonyl oxygen atoms with sulfur atoms in the extraction of Cu2+. The complexation behavior of 4, 6, and 8 with Cu2+ was also examined by UV-Vis and NMR techniques. 展开更多
关键词 aromatic oligothioamide hydrogen bonding copper selective extraction cation receptor
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