碳纳米管膜的制备及其研究进展

碳纳米管众多优良性质，并不仅仅体现在单根碳纳米管中，更多的是在大量的碳纳米管的集中体现，即碳纳米管膜的性质与应用。本文根据碳纳米管膜中碳纳米管的排列方式不同，详细介绍了无序碳纳米管膜、水平有序碳纳米管膜及垂直有序碳纳米管膜的制备方法、应用现状及其面临的挑战。     

Zur Wasserpermeabilität des Protoplasmas

Summary The permeability of cells to dissolved molecules is given by the permeation constant ofCollander (cm·h^–1), whilst the permeability to water is measured by a filter constant (cm·Atm.^–1·h^–1). Therefore these constants are not comparable, and it is impossible to calculate quantitative data on the semipermeability of a cell.In this paper the permeation process is considered as a counterdiffusion of dissolved molecules into the cell and water out of the cell. From the two resulting diffusion equations formulae and a graphic method are derived, which permit to calculate the permeation constant of water, when the permeation constant of a given substance entering the cell is known. These constants are comparable and their ratio is a conclusive measure of the semipermeability.     

A micro-electrode amplifier with an infinite resistance current source for intracellular measurements of membrane potential and resistance changes under current clamp.

A microelectrode amplifier for intracellular electrophysiological research is described. It is equipped with an electronic infinite resistance constant current source for the injection of current into biological cells. With this amplifier the potential changes, the resistance changes and the dependence on extrinsic current of single cells can be measured independently and simultaneously.     

多孔Cu2O／SnO2复合薄膜的制备及其可见光催化降解罗丹明B的性能

采用浸渍-沉积方法在电沉积的多孔Cu薄膜上修饰一层纳米SnO2，经低温热氧化处理制备出多孔Cu2O／SnO2复合多层薄膜。运用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、X-射线粉末衍射仪（XRD）、紫外可见漫反射光谱（UV—vis DRS）和荧光光谱（FS）技术表征了薄膜的结构、形貌和光学性质。测试了薄膜在可见光下降解罗丹明B（RhB）的性能。结果表明，在30℃的0．2mol／LCuSO4＋1．5mol／L H2SO4镀液中，以1.5A／cm^2电流沉积20s得蓟的多孔Cu薄膜，在SnO2溶胶中浸渍10s并重复5次，再经空气气氛下100℃焙烧30min，锻得的多孔复夸薄膜显示良好的可见光催化降解RhB的性铯。     

工作气压对磁控溅射法制备硼碳氮薄膜结晶度的影响

本文用六方氮化硼和石墨靶材采用射频（频率为13．56MHz）磁控溅射法沉积硼碳氮薄膜，得到的硼碳氮薄膜可用红外，拉曼表征。工作气压从0．2Pa升高到6．0Pa。我们可以观察到工作气压可以明显的改变硼碳氮薄膜的晶体结构和结晶度。硼碳氯薄膜的半高宽随工作气压的增加而变化并且在工作气压1．0Pa时得到较好结晶度的薄膜。     

Fifty years of amanitin.

Pharmacokinetic studies have provided new insights into human Amanita poisoning, but it appears to be impossible to treat this intoxication by immunotherapy. New synthetic analogs have revealed structure-activity relationships that were unknown so far. The main toxin, alpha-amanitin, is in constant use as a tool in molecular biology and in biological research. First experiments have been reported in which amanitin bound to polymers could be internalized into tumor cells via a receptor-mediated endocytosis.     

Fifty years of amanitin

Pharmacokinetic studies have provided new insights into humanAmanita poisoning, but it appears to be impossible to treat this intoxication by immunotherapy. New synthetic analogs have revealed structure-activity relationships that were unknown so far. The main toxin, α-amanitin, is in constant use as a tool in molecular biology and in biological research. First experiments have been reported in which amanitin bound to polymers could be internalized into tumor cells via a receptor-mediated endocytosis.     

Exponential smoothing: Behavior of the ex-post sum of squares near 0 and 1

When using simple exponential smoothing on a given time series the nature of the relationship between the optimal smoothing constant and the autocorrelation structure of the series remains an unresolved question. Although numerical search routines can easily be used to find optimal values of the smoothing constant, they offer little insight into the nature of the relationship between the estimated smoothing constant and the structure of the underlying time series. We suggest that renewed investigations of the ex-post sum of squares function may prove helpful in this pursuit. Results are presented that illustrate how the optimal smoothing constant depends upon the value used to initialize the smoothing and upon the sample autocorrelation coefficients of the observed series. These results are based on a new formula for the derivative of the ex-post sum of squares function. In particular, the derivative is examined near 0 and 1, where great simplifications occur in its form, thereby facilitating investigations near these points. A necessary and sufficient condition is stated for when the ex-post sum of squares must have a positive derivative at 0 and the autocorrelation coefficients of the differenced series are shown to affect the sign of the derivative near 1. Based on these results, a general algorithm is presented as an alternative to grid search routines for minimizing the ex-post sum of squares.     

Registration of feeding behaviour in rats by recording food approach behaviour.

A method is described in which food approach behaviour of rats is recorded to study feeding behaviour. Between rats, differences in food approach behaviour were observed. For each rat, food approach behaviour was constant over a long period of time. This allows conversion of approach behaviour data into quantified feeding behaviour. Examples of long-term feeding behaviour and of reproducibility of food intake are given.     

Registration of feeding behaviour in rats by recording food approach behaviour

Summary A method is described in which food approach behaviour of rats is recorded to study feeding behaviour. Between rats, differences in food approach behaviour were observed. For each rat, food approach behaviour was constant over a long period of time. This allows conversion of approach behaviour data into quantified feeding behaviour. Examples of long-term feeding behaviour and of reproducibility of food intake are given.     

Investigations of ZnO thin films deposited by a reactive pulsed laser ablation

Highly transparent ZnO thin films were deposited at different substrate temperatures by pulsed laser deposition in an oxygen atmosphere.The thin films were characterized by various techniques including X-ray diffraction,scanning electron microscopy,optical absorption,and photoluminescence.We demonstrated that oriented wurtzite ZnO thin films could be deposited at room temperature using a high purity zinc target.Variable temperature photoluminescence revealed new characteristics in the band edge emission.The...     

不锈钢表面ZnO-尖晶石复合氧化膜的制备及其可见光光催化性能

通过电沉积锌及空气气氛下两步热氧化，在304不锈钢表面形成具有可见光光催化活性的ZnO复合氧化物薄膜。运用X-射线衍射（XRD）、拉曼光谱（Rarnan）、扫描电子显微镜（SEM）分析薄膜的结构及表面形貌，在可见光照射下测试了氧化膜催化降解罗丹明B的性能。结果显示：在0．05m0I／LZnSO4、2moL／LNH4Cl溶液中，以0．03A／cm^2的恒电流密度阴极极化120s，电沉积锌后于空气气氛中350℃下加热1h，然后升温至450℃下加热2h，在不锈钢表面形成了ZnO和尖晶石结构氧化物（AB2O4，A=Zn^2＋、Ni^2＋、Fe^2＋；B=Fe^3＋，Cr^3＋）的复合氧化膜，显示出良好的可见光光催化性能。     

Cu_2ZnSnS_4 thin films prepared by sulfurizing different multilayer metal precursors

Cu2ZnSnS4(CZTS)thin films were successfully fabricated on glass substrates by sulfurizing Cu-Sn-Zn multilayer precursors,which were deposited by ion beam sputtering and RF magnetron sputtering,respectively.The structural,electrical and optical properties of the prepared films under various processing conditions were investigated in detail. Results showed that the as-deposited CZTS thin films with the precursors by both ion beam sputtering and RF magnetron sputtering have a composition near stoichiometric.Th...     

Über das Hauptproblem bei konvexen Rotationskörpern

Summary It is shown that over the distance 0X8/² in the diagram, there is a region which is free from picture points («Bildpunkten») of the convex rotation bodies. This assertion is based on two different groupings of the convex rotation bodies into troops, namely at constant lengthl and constant radius of the equatorr, and at constantl and constant length of the resulting meridial curveL. From this, new relations like between the measurements of the convex rotation bodies follow.     

Room temperature ferromagnetism of Ni,(Ni,Li),(Ni,N)-doped ZnO thin films

Ni-doped ZnO thin films (Ni concentration up to 10 mol%) were generated on Si (100) substrates by a sol-gel technique. The films showed wurtzite structure and no other phase was found. The chemical state of Ni was found to be bivalent by X-ray photoelectron spectroscopy. The results of magnetic measurements at room temperature indicated that the films were ferromagnetic, and magnetic moment decreased with rise of Ni concentration. The magnetization of Ni (10 mol%)-doped ZnO film annealed in nitrogen was low...     

Non-enzymatic active transport in vitro. Conversion of chemical to osmotic energy]

The active transport of ammonia gas was obtained with an asymmetric composite membrane-model using H+ as carrier and the formation of water as chemical energy source. The experimental molecular pump externally limited by two silicone films permeable to gasses but not to liquids or ions is separated into two liquid layers by a central cation-exchange membrane. The first acid layer produces the aspiration of NH3, due to NH4+ formation, through the inlet silicone film; NH4+ is transferred to the second alkaline layer through the ion exchange membrane, by interdiffusion with K+; there NH4+ reacts with OH-, water is formed and NH3 is expelled throught the oulet silicone film. This new pump enlarges the applicability of in vitro active transport to non-enzymatic systems and energy sources different from ATP.     

Effects of hypothalamic injections of 5,6-dihydroxytryptamine on thermoregulation in rats.

5,6-Dihydroxytryptamine, a serotonin depletor, infused directly into the anterior hypothalamus of rat's brain, produced an increase in both heat production and heat loss (as indicated by changes in peripheral circulation) at temperatures of 8, 15 and 22 degrees C. The rectal temperature of these treated rats remained constant.     

The cosmological constant, the fate of the universe, unimodular gravity, and all that

The cosmological constant is back. Several lines of evidence point to the conclusion that either there is a positive cosmological constant or else the universe is filled with a strange form of matter (“quintessence”) that mimics some of the effects of a positive lambda. This paper investigates the implications of the former possibility. Two senses in which the cosmological constant can be a constant are distinguished: the capital Λ sense in which lambda is a universal constant on a par with the charge of the electron, and the lower case λ sense in which lambda is a humble constant of integration. The latter interpretation has been touted as the means to a solution to various problems in physics. These claims are critically examined with an eye to discerning the implications for philosophy of science and foundations of physics.     

Effects of hypothalamic injections of 5,6-dihydroxytryptamine on thermoregulation in rats

Summary 5,6-Dihydroxytryptamine, a serotonin depletor, infused directly into the anterior hypothalamus of rat's brain, produced an increase in both heat production and heat loss (as indicated by changes in peripheral circulation) at temperatures of 8, 15 and 22°C. The rectal temperature of these treated rats remained constant.This work was supported by grants from National Science Council of Taiwan and J. Aron Charitable Foundation (USA). The author is grateful to Dr C. Y. Chai and Mr C. C. Wei for their support.     

聚合物超薄膜结晶相关的形貌形成及链行为

聚合物超薄膜结晶是高分子物理领域的一个新研究课题,近来已引起人们的关注,其为人们在真实时空下研究聚合物结晶及相关链行为提供了可能。聚合物超薄膜结晶与膜厚(D)有很强的相关性,尤其是D<20nm的薄膜在结晶形貌和结晶动力学方面与本体结晶差别很大。已有的结果主要集中在结晶形貌、晶体尺寸、晶体生长速度和习性、晶体的熔融和结晶度等方面,涉及温度、膜厚、基片性质和膜的组成和结构对结晶的影响;然而,有些实验结果和解释彼此不完全一致,甚至有时相互矛盾。本文综述和讨论了近年来在超薄膜结晶方面的研究,重点在于结晶形貌的形成和相关的聚合物链行为。