Effect of gas mixing ratio on gas-phase composition and etch rate in an inductively coupled CF4/Ar plasma

In this work, we carried out investigations aimed at understanding the effect of gas mixing ratio on plasma parameters, gas phase composition and etch rate in CF₄/Ar inductively coupled plasma. For this purpose, a combination of experimental methods and modelling was used. Experiments showed that electron temperature and electron density are not very sensitive to variations of Ar content in CF₄/Ar plasma. From a zero-dimensional plasma model, the densities of both neutral and charged particles change monotonically. The analysis of surface kinetics based on an ion-assisted etching mechanism showed the possibility of non-monotonic etch rate behaviour due to a concurrence of chemical and physical etching pathways.     

调理心肾中药对拟痴呆大鼠脑组织中M和GABA受体功能的影响

以~3H-QNB和~3H-GABA为放射性配基,用受体放射性配基结合分析法,测出拟痴呆模型大鼠大脑皮层和海马组织中的M受体和小脑组织中的GABA受体的R_t值明显降低;M受体的K_D值在大脑皮层中明显减少,在海马中略有升高。小脑中GABA受体的K_D值显著降低。调理心肾中药及喜德镇(Hydergin,为国外常用抗老年痴呆药)能使降低的M受体和GABA受体的R_t值均明显升高,接近正常水平。对K_D值则有不同程度的调整作用。     

Electrochemical injection of organic corrosion inhibitors into carbonated cementitious materials: Part 1. Effects on pore solution chemistry

This series of investigations was intended to clarify phenomena associated with electrochemical injection of the organic base corrosion inhibitors, ethanolamine and guanidine, into carbonated concrete. In Part 1, experiments were conducted with laminated specimens of carbonated cement paste, that were specially designed to facilitate analysis with adequate spatial resolution to assess changes in their pore solution phase chemistry after they had been subjected to constant current electrolysis between embedded cathodes and external anodes. The anolyte solutions provided sources of ethanolamine or guanidine in contact with the exterior specimen surfaces. Effects of variations in the applied current density and duration of electrolysis on the concentration profiles of the two inhibitors and the other main constituents of the pore solution phase were determined. The results have been used to underpin the development of a mathematical model, which is described in Part 2.     

Etching characteristics and mechanism of Pb(Zr,Ti)O3 thin films in CF4/Ar inductively coupled plasma

The effect of the CF₄/Ar mixing ratio on the etching behaviour and mechanisms for Pb(Zr,Ti)O₃ (PZT) thin films in an inductively coupled plasma was carried out. It was found that an increase of Ar mixing ratio causes non-monotonic behaviour of the PZT etch rate, which reaches a maximum of 2.38 nm/s at 80% Ar. Investigating the plasma parameters, we found a weak sensitivity of both electron temperature and electron density to the change of CF₄/Ar mixing ratio. A combination of zero-dimensional plasma model with the model of surface kinetics shows the possibility of a non-monotonic etch rate behaviour due to the concurrence of physical and chemical pathways in the ion-assisted chemical reaction.     

A Review of: “Noise and Society”. Edited by D. M. JONES and A. J. CHAPMAN. (Chichester: John Wiley & Sons.) [Pp.xi + 319.] Cloth £18·75. ISBN 0-471-90357-4.

Abstract

Continuous records of sleep, sleepiness, urine samples and subjective fatigue ratings were obtained from and continuous monitoring of their temperature and electrocardiogram (ECG) was carried out on 12 B747 cockpit crewmembers during a base-line period of 36 h, 3 days of operating regular passenger flights between Frankfurt’ (FRA) and San Francisco (SFO) and 44 h after their return to Germany. This paper deals with the circadian aspects of hormone and electrolyte excretion in addition to those of rectal temperature and ECG. Normal circadian phase relations of these functions were disrupted due to the time zone transitions of 9 h in both directions. Internal dissociation was most pronounced on the second day in SFO, with maximum shifts in acrophases up to 12.5 h for sodium and minimum shifts of about 2 h for 17-hydroxycorticosteroids (17-OHCS) excretion rates. After the return flight, readaptation to local time in Germany also differed among functions, but to a minor degree: the range of internal dissociation was reduced to 3 h, with extreme values observed in the curves of sodium excretion (delay of about 3.75 h) and of heart rate (delay of 0.6 h). The coupling with internal synchronizers varied considerably between the different measured parameters. Some body functions, such as 17-OHCS and temperature, were only slightly influenced by external factors. Others, such as heart rate and sodium excretion rates, were much more affected, e.g. by sleep, activity and food intake. From our findings we conclude that, due to dissociation and desynchronization, irregular work hours for pilots lead to rhythm disturbances, which may impair the well-being and, in some cases, may also affect the performance of aircrew during duty.     

Thermodynamic Properties of Ionic Semiclathrate Hydrate Formed with Tetrabutylammonium Propionate

The phase equilibrium temperature and dissociation heat of tetrabutylammonium propionate (TBAPr) hydrate are reported. TBAPr hydrate is a type of ionic semiclathrate hydrates and also could potentially be used as thermal energy storage material. The temperature‐composition phase diagram of the TBAPr hydrate was determined in a defined range of mass fractions. Considering the dissociation heat of differential scanning calorimetry (DSC) measurements, multiple peaks of heat flow were observed in the TBAPr‐water system at the TBAPr mass fraction lower than 0.35, and there was a single peak at the mass fraction higher than 0.37.     

用于海水中实时测量的氨氮测量仪

本文介绍一种新型的用于海水中实时测量的氨氮传感器。该传感器具有NH3／pH/T三电极复合式探头,能实时地将海水的酸度,温度以及氨的含量快速准确地测量,并由DSP（TMS320F206）为核心的数字信号处理系统对测量结果进行收集,分析处理,通过RS232／RS485将数据传送至陆地上的主系统。传感器处于自动运行模式。可在海水中连续一个月无故障工作,测量精度好于10％。     

Measurement for dissociation ratio of source gases in plasmas using a quartz sensor

The dissociation ratio of source gas molecules is measured using a quartz sensor, for which the output depends on the average molecular weight and viscosity of gases. The change in the pressure and temperature-normalized quartz sensor output (NQO) by discharge correlates with changes of the signal intensity of the source gas of ammonia (NH₃), as measured by gas analysis using a quadrupole mass spectrometer. Thereby, the dissociation ratio is obtainable from the change in NQO by the discharge. The spatial distributions of the change in NQO in the plasma chamber show a larger change in NQO near the plasma electrode, indicating that the change in NQO correlates with the dissociation ratio of NH₃. Finally, the dissociation ratios of NH₃ near and between the plasma electrodes were obtained from the spatial distribution of the dissociation ratio of NH₃. Results show that the Q-sensor measurement is simple and useful to derive the dissociation ratio of the source gases for the plasmas of reactive gases.