Gyro-Landau-fluid simulations of impurity effects on ion temperature gradient driven turbulence transport

The effects of impurities on ion temperature gradient(ITG)driven turbulence transport in tokamak core plasmas are investigated numerically via global simulations of microturbulence with carbon impurities and adiabatic electrons.The simulations use an extended fluid code(ExFC)based on a four-field gyro-Landau-fluid(GLF)model.The multispecies form of the normalized GLF equations is presented,which guarantees the self-consistent evolution of both bulk ions and impurities.With parametric profiles of the cyclone base case,well-benchmarked ExFC is employed to perform simulations focusing on different impurity density profiles.For a fixed temperature profile,it is found that the turbulent heat diffusivity of bulk ions in a quasi-steady state is usually lower than that without impurities,which is contrary to the linear and quasilinear predictions.The evolutions of the temperature gradient and heat diffusivity exhibit a fast relaxation process,indicating that the destabilization of the outwardly peaked impurity profile is a transient state response.Furthermore,the impurity effects from different profiles can obviously influence the nonlinear critical temperature gradient,which is likely to be dominated by linear effects.These results suggest that the improvement in plasma confinement could be attributed to the impurities,most likely through adjusting both heat diffusivity and the critical temperature gradient.

Seasonal constraint of dynamic water temperature on riverine dissolved inorganic nitrogen transport in land surface modeling

水体温度变化对河流可溶性无机氮(DIN)输送有着强烈控制作用.然而,在全球尺度上河流DIN输送量对水温度变化的响应尚不清楚.因此,本文基于陆面过程模式,耦合河流水温估算和DIN传输方案,设定有,无动态水温情景,对比研究陆面模拟中水温变化对河流DIN通量变化的影响.结果表明:在考虑水温动态变化后,在30°N和30°S之间, DIN通量年振幅减小5%–25%.在中国东部地区,水温动态变化使河流DIN通量在夏季减少1%–3%,在冬季增加1%–5%,对DIN通量具有明显的季节性约束作用,表明动态水温的表达在河流DIN输送模拟中的重要性.

Modeling viscosity of methane,nitrogen,and hydrocarbon gas mixtures at ultra-high pressures and temperatures using group method of data handling and gene expression programming techniques

Accurate gas viscosity determination is an important issue in the oil and gas industries.Experimental approaches for gas viscosity measurement are timeconsuming,expensive and hardly possible at high pressures and high temperatures(HPHT).In this study,a number of correlations were developed to estimate gas viscosity by the use of group method of data handling(GMDH)type neural network and gene expression programming(GEP)techniques using a large data set containing more than 3000 experimental data points for methane,nitrogen,and hydrocarbon gas mixtures.It is worth mentioning that unlike many of viscosity correlations,the proposed ones in this study could compute gas viscosity at pressures ranging between 34 and 172 MPa and temperatures between 310 and 1300 K.Also,a comparison was performed between the results of these established models and the results of ten wellknown models reported in the literature.Average absolute relative errors of GMDH models were obtained 4.23%,0.64%,and 0.61%for hydrocarbon gas mixtures,methane,and nitrogen,respectively.In addition,graphical analyses indicate that the GMDH can predict gas viscosity with higher accuracy than GEP at HPHT conditions.Also,using leverage technique,valid,suspected and outlier data points were determined.Finally,trends of gas viscosity models at different conditions were evaluated.

Effects of Transport,Storage Temperature and Time on Parthenogenetically Developmental Competence of Sheep Oocyte

This study was to investigate the effects of transport, storage temperature and time on parthenogenetical developmental competence of sheep oocyte. The ovaries were collected and randomly immersed in physiological saline at （ 10 - 15 ） ℃, （20 - 25 ） ℃ and （30 - 35 ） ℃ and transported to the laboratory for culture. They were divided into three groups randomly in an optimized transport temperature, kept in physiological saline at4 ℃, （14 -18） ℃ and （25 -30） ℃ respectively; 15 - 17 h later, the ovaries were cutured for the maturation and parthenogenetic activation of oocytes. The results showed that the optimal transport temperature of ovaries was 20 -25 ℃, when the maturation rate and blastocysts rate reached 67.44% and 35.93% respectively. Incubating sheep ovaries at （ 14 - 18 ） ℃ for （15 -17） h did not reduce the maturation rate （61.81%） and blastocysts rate （29.03%） of oocyte significantly. However, incubating sheep ovaries at 4 ℃ or （25 -30） ℃ significantly reduced the maturation rate （41.90%, 18.40% ） and cleavage rate （9.09%, 13.04% ）, and the ovaries could not develop into blastocysts at these two temperature ranges. It can be concluded that the optimal transport temperature of the sheep ovaries is 20 - 25 ℃, and incubation at 14 - 18 ℃ overnight in vivo does not affect the developmental competence of oocytes.

Study of relationship between wave transport and sea surface temperature anomaly(SSTA) in the tropical Pacific

Large-scale water transport is one of the key factors that affect sea surface temperature anomaly（SSTA） in the eastern equatorial Pacific（EEP）.The relationship between the wave transport in the tropical Pacific and the SSTA in the EEP is examined by different methods,including band-pass filtering,period analysis,correlation analysis,significant analysis,and empirical orthogonal function（EOF） analysis.We have found that the eastward shift of the wave transport anomaly in the tropical Pacific,with a period of 2 a and enhancing the transport of warm waters from the western Pacific warm pool,precedes the increase of sea surface temperature（SST） in the EEP.The wave transport and the SSTA in the EEP have a maximum correlation of 0.65 with a time-lag of 6 months（transport variation precedes the temperature）.The major periods（3.7 a and 2.45 a） of the wave transport variability,as revealed by the EOF analysis,appear to be consistent with the SSTA oscillation cycle in the EEP.Based on the first occurrence of a significant SSTA in the Ni？o 3 region（5°S–5°N,90°–150°W）,two types of warm events are defined.The wave transport anomalies in two types present predominantly the west anomaly in the tropical Pacific,it is that the wave transport continues transport warm water from west to east before the onset of the warm event.The impact of wave-induced water transport on the SSTA in the EEP is confirmed by the heat flux of the wave transport.The wave transport exerts significant effect on the SSTA variability in the EEP and thus is not neglectable in the further studies.

Quantum transport characteristics in single and multiple N-channel junctionless nanowire transistors at low temperatures

Single and multiple n-channel junctionless nanowire transistors （JNTs） are fabricated and experimentally investigated at variable temperatures. Clear current oscillations caused by the quantum-confinement effect are observed in the curve of drain current versus gate voltage acquired at low temperatures （10 K-100 K） and variable drain bias voltages （10 mV- 90 mV）. Transfer characteristics exhibit current oscillation peaks below flat-band voltage （VFB） at temperatures up to 75 K, which is possibly due to Coulomb-blocking from quantum dots, which are randomly formed by ionized dopants in the just opened n-type one-dimensional （1D） channel of silicon nanowires. However, at higher voltages than VFB, regular current steps are observed in single-channel JNTs, which corresponds to the fully populated subbands in the 1D channel. The subband energy spacing extracted from transconductance peaks accords well with theoretical predication. However, in multiple-channel JNT, only tiny oscillation peaks of the drain current are observed due to the combination of the drain current from multiple channels with quantum-confinement effects.

The relation between ambulance transports due to heat stroke and air temperature using daily data in Okayama prefecture, Japan

The aim of this study was to investigate the link between ambulance transports due to heat stroke and air temperature by using daily data of ambulance transports in Okayama prefecture, Japan. Daily observations for ambulance transports due to heat stroke from July to September in 2010 in Okayama prefecture, Japan were obtained from Fire and Disaster Management Agency in Japan. Data of meteorological parameters in Okayama prefecture, Japan were also obtained from Japan Meteorological Agency. Effect of meteorological parameters on ambulance transports due to heat stroke was analyzed. A total of 1133 ambulance transports due to heat stroke were observed in from July to September of 2010 in Okayama prefecture, Japan. Ambulance transports due to heat stroke was significantly correlated with air temperature. In addition, number of subjects with ambulance transports due to heat stroke over 34°C in the highest air temperature was 21.2 ± 9.8 per day. Higher air temperature was closely associated with higher ambulance transports due to heat stroke by using daily data in Okayama, prefecture, Japan.

Influence of Oil and Water Components on Wall-sticking Occurrence Temperature in High Water-cut Crude Oil Pipeline

To study the wall-sticking phenomenon and prevent pipeline blockage accidents,two analytical methods are used to evaluate the influence of different crude oil components on the wall-sticking occurrence temperature(WSOT).The WSOT and the interactions among oil,water,and surface solids are measured and calculated by various devices under different values of the wax content,water pH,and salinity.The results show that there is greater correlation between the wax content and WSOT than between resins/asphaltenes and WSOT.Furthermore,the wax content,water pH,and salinity have different effects on WSOT.There is generally a positive correlation between wax content and WSOT,whereas the maximum WSOT occurs when the water pH is in the range 5.7–6.5,and decreases under more acidic or alkaline conditions.As the salinity increases,WSOT decreases slightly,but quickly becomes saturated.In terms of interactions,variations in the interfacial tension and adhesion work with pH and salinity are consistent with that of WSOT,while the contact angle exhibits the opposite relation.

Evaluation of Energy Band Gap, Thermal Conductivity, Phase Transition Temperature and Elastic Response of PS/CdS Semiconducting Optical Nanocomposite

Thick film of Polystyrene (PS)/CdS semiconducting optical nanocomposite has been synthesized by dispersing nanofiller particles of CdS in PS matrix. The nanostructure of the CdS particles has been ascertained through X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). Small angle x-ray scattering analysis has been performed in order to ascertain nanocomposite character of the PS/CdS sample. Scanning Electron Microscopy (SEM) analyses of these samples have been carried out to establish the surface morphology. Optical Absorption Spectroscopy is used to measure the energy band gap of PS/CdS nanocomposite by using Tauc relation whereas Transient Plane Source Technique is used for the determination of thermal conductivity of the prepared samples. The phase transition temperature and elastic response of the prepared samples have been ascertained through Dynamic Mechanical Analyzer (DMA). This study reveals that the thermal conductivity, Young’s modulus and the toughness of the material are greatly influenced by the existence of interfacial energetic interaction between dispersed CdS nanofiller particles and matrix of PS.

A low temperature processable tin oxide interlayer via aminemodification for efficient and stable organic solar cells

The exploitation of proper electron transport layers(ETLs)and interface optimization can play a pivotal role to promote the performance of organic solar cells(OSCs).In this work,low temperature processable tin oxide(SnO_(2))colloidal nanoparticles with ethanolamine(EA)treatment are successfully employed for efficient and stable OSCs with light soaking free.The EA is chemically bonded with SnO_(2),and the ethanolamine treated tin oxide(E-SnO_(2))layer delivers a suitable work function of 4.10 eV and a unique surface texture with suspended polar moieties.The enhanced performance of E-SnO_(2) based OSCs can be attributed to the improved charge transport and electron extraction,which is correlated with the regulated energy level alignment and contact quality of E-SnO_(2)/active layer.As a result,considerable power conversion efficiencies(PCEs)of 10.30%,13.93%and 15.38%for PTB7-Th/PC_(71) BM,PM7/ITC6-4 F and PM6/Y6 based OSCs have been realized with E-SnO_(2) as ETL,respectively.Compared with ZnO based devices,the E-SnO_(2) based OSCs exhibit an improved light aging stability,which can retain 94.3%of their initial PCE of 15.38%after 100 h light aging for E-SnO_(2)/PM6/Y6 based OSCs.This work demonstrates that the enormous potential of E-SnO_(2) to serve as ETL for high-efficiency and stable OSCs.

Effects of water on the structure and transport properties of room temperature ionic liquids and concentrated electrolyte solutions

Transport properties and the associated structural heterogeneity of room temperature aqueous ionic liquids and especially of super-concentrated electrolyte aqueous solutions have received increasing attention,due to their potential application in ionic battery.This paper briefly reviews the results reported mainly since 2010 about the liquid-liquid separation,aggregation of polar and apolar domains in neat RTILs,and solvent clusters and 3D networks chiefly constructed by anions in super-concentrated electrolyte solutions.At the same time,the dominating effect of desolvation process of metal ions at electrode/electrolyte interface upon the transport of metal ions is stressed.This paper also presents the current understanding of how water affects the anion-cation interaction,structural heterogeneities,the structure of primary coordination sheath of metal ions and consequently their transport properties in free water-poor electrolytes.

Physiological Responses of Clam(Ruditapes philippinarum)to Transport Modes with Different Temperatures

Given the increased circulation time after fishing,a series of changes take place in live clams,leading to a deterioration in quality even after death.Thus,in this study,we aimed to explore the optimal mode of transportation of clams.The container for holding clams was reformed,and a water circulation temperature control system was established.The physiological responses of clams during anhydrous and watery transportation at two temperatures(4 and 15℃)were investigated based on the aforementioned system.When comparing the transportation patterns after 3 d of transport,a higher survival rate was observed at 4℃(97%)than at 15℃(63%)in the anhydrous transportation groups and a lower survival rate was observed at 4℃(93%)than at 15℃(99%)in the watery transportation groups.In addition,the glycogen content,condition index(CI),and adenylate energy charge(A.E.C)value were higher at4℃((40.87±0.99)mg g^(-1),13.71%±0.50%and 57.45%±1.60%)than at 15℃((30.54±0.81)mg g^(-1),9.09%±0.30%and 43.12%±1.65%)in the anhydrous transportation groups.In the watery transportation groups,a lower glycogen content,CI,and A.E.C.value were observed at 4℃((33.78±0.84)mg g^(-1),9.78%±0.50%and 64.65%±1.25%)than at 15℃((41.53±0.93)mg g^(-1),12.72%±0.83%and 71.58%±1.27%).Results from this study show that anhydrous transportation(4℃)is the optimal transport condition for clams to maintain a high quality and good physiological conditions.Thus,this study will be particularly useful for establishing shellfish transportation systems.

Anomalous transport driven by ion temperature gradient instability in an anisotropic deuterium-tritium plasma

In this work,the anomalous transport driven by the ion temperature gradient instability is investigated in an anisotropic deuterium-tritium(D-T)plasma.The anisotropic factorα,defined as the ratio of perpendicular temperature to parallel temperature,is introduced to describe the temperature anisotropy in the equilibrium distribution function.The linear dispersion relation in local kinetic limit is derived,and then numerically evaluated to study the dependence of mode frequency on the anisotropic factorαof D and the fraction of T particleεTby choosing three sets of typical parameters,denoted as the cyclone base case,ITER and CFETR cases.Based on the linear results,the mixing length model approximation is adopted to analyze the quasi-linear particle and energy fluxes for D and T.It is found that choosing smallαand largeεTis beneficial for the confinement of particle and energy for D and T.This work may be helpful for the estimation of turbulent transport level in the ITER and CFETR devices.

Design consideration of a super-high speed high temperature superconductor maglev evacuated tube transport (I)

The super-high speed high temperature superconductor （HTS） maglev evacuated tube transport （ETT） is a promising transport mode for the future. As a key component of the HTS maglev vehicle, the permanent magnet guide- ways （PMGs） with different geometrical configurations and iron yoke widths are analyzed by finite element method （FEM）. The levitation force of a single onboard HTS maglev device over the designed PMG at different field cooling heights （FCH） is measured by magnetic levitation measurement system. Based on the designed PMG and experimental results, a preliminary scheme of subterranean super-high speed HTS maglev ETT is described in this paper. The HTS maglev ETT is mainly composed of an evacuated tube, HTS maglev vehicle, PMG, propulsion system, station, emergency rescue system, etc. In addition, a subterranean tube that consists of foundation tube and vacuum airproof layer is introduced. In order to convert the stress caused by the air pressure difference between inside and outside of the vehicle, a multi-circular vehicle body is designed. The vehicle is driven by a linear motor propulsion system under the control of a ground controlling system. The scheme of long-distance super-high speed passenger transportation is accomplished by the connection of different vehicles.

The higher air temperature was closely associated with higher ambulance transports due to heat stroke in elderly Japanese

To investigate the link between higher air temperature and ambulance transports due to heat stroke, especially in elderly subjects, using daily data in Sai-tama prefecture in August, 2010, Japan. We obtained daily data of air temperature in Saitama prefecture in August, 2010, Japan from Japan Meteorological Agency. Number of ambulance transports due to heat stroke was also used by Saitama prefecture official website. The effect of high air temperature on am-bulance transports due to heat stroke was evaluated. A total of 1688 ambulance transports due to heat stroke was observed in Saitama prefecture in August, 2010, Japan. Seven hundred and twenty one subjects (42.7%) were over the age of 65. Mean air temperature, the highest air temperature and day light hours were significantly associated with ambulance transports due to heat stroke in total subjects (mean air temperature: r = 0.749, p < 0.0001) and the over the age of 7. In addition, by separate analysis as classified by age groups, the correlation coefficient between ambulance transports due to heat stroke and mean air temperature was the highest in subjects with over 65. However, the lowest air temperature was not cor-related with ambulance transports due to heat stroke. Higher air temperature was closely associated with higher ambulance transports due to heat stroke using daily data in Saitama prefecture in August, 2010, Ja-pan, especially in elderly subjects.

Nonlocal Theory of High-Temperature Superconductivity

The Boltzmann local physical kinetics forecasts the destruction of SC regime because of the heat movement of particles. Then, the most fundamental distinction between a strange metal and a conventional metal is the absence of well-defined quasi-particles. Here, we show that the mentioned “quasi-particles” are solitons, which are formed as a result of self-organization of ionized matter. Shortcomings of the Boltzmann physical kinetics consist in the local description of the transport processes on the level of infinitely small physical volumes as elements of diagnostics. The non-local physics leads to the theory superconductivity including the high temperature diapason. The generalized non-local non-stationary London’s formula is derived.

Quantifying the non-conservative production of potential temperature over the past 22000 years

The energy budgets of the ocean play a crucial role in the analysis of climate change. Potential temperature is traditionally used as a conservative quantity to express variations associated with “heat” in oceanography, such as the heat content and heat transport. However, potential temperature is usually not conserved during turbulent mixing, so the use of conservative temperature is more accurate. Based on climatological simulations under the modern and Last Glacial Maximum (LGM;~21 ka;ka=thousand years ago), as well as a transient climate simulation of the past 22 000 years, we quantify the errors induced by the neglect of the non-conservation of potential temperature in paleo-climate research for the first time. The temperature error reaches 0.9℃ near the coasts aff ected by river discharges but is much smaller in the open oceans, typically 0.03°C above the main thermocline and less than 0.01℃ elsewhere. The error of the ocean heat content (OHC) is roughly 3×10^22 J and is relatively steady over the past 22 000 years. However, the OHC increases to six times the original value during the last glacial termination from 20 ka to 7 ka. As a result, the relative OHC error decreases from 1.2% in the LGM climate to 0.14% in the modern climate. The error of the ocean meridional heat transport (OMHT) is generally smaller than 0.005 PW (1 PW=10 15 W), with very small temporal variations (typically 0.000 4 PW), and induces a relative OMHT error of typically 0.3% over the past 22 000 years. Therefore, the neglect of the non-conservation of potential temperature induces a relative error of generally less than 1% in the analyses of basin-scale climate variations.

Influences of Temperature on Proton Conductivity in the Hydrogen-Bond Molecular Systems with Damping

Influences of temperature of medium on proton conductivity in hydrogen-bonded systems exposed in an electricfield are numerically studied by the fourth-order Runge-Kutta method with our model. The results obtained show that the proton soliton is very robust against thermal perturbation and damping of medium, and is thermally stable in the temperature range T ≤ 273 K. From the simulation we find out that the mobility （or velocity） of proton conduction in ice crystal is a nonmonotonic function of temperature in the temperature range 170-273 K： i.e., it increases initially, reaches a maximum at about 191 K, subsequently decreases to a minimum at about 211 K, and then increases again. This changed rule of mobility is qualitatively consistent with its experimental data in ice in the same temperature range. This result provides an evidence for existence of solitons in the hydrogen-bonded systems.

Schottky forward current transport mechanisms in AlGaN/GaN HEMTs over a wide temperature range

The behavior of Schottky contacts in AlGaN/GaN high electron mobility transistors （HEMTs） is investigated by temperature-dependent current-voltage （T-I-V） measurements from 300 K to 473 K. The ideality factor and barrier height determined based on the thermionic emission （TE） theory are found to be strong functions of temperature, while present a great deviation from the theoretical value, which can be expounded by the barrier height inhomogeneities. In order to determine the forward current transport mechanisms, the experimental data are analyzed using numerical fitting method, considering the temperature-dependent series resistance. It is observed that the current flow at room temperature can be attributed to the tunneling mechanism, while thermionic emission current gains a growing proportion with an increase in temperature. Finally, the effective barrier height is derived based on the extracted thermionic emission component, and an evaluation of the density of dislocations is made from the I-V characteristics, giving a value of 1.49 × 10^7 cm^-2.