Phytotoxicity of a surfactant-containing product towards macrophytes

Extending the studies of surfactant-containing products, we have investigated the effect of the Liquid Crystal Concentrate detergent on aquatic macrophytes Elodea canadensis within laboratory microcosms. It has been shown that the detergent produced some negative influence on the macrophytes at 50–150 μL/mL (5–15 vol %).     

Synthesis of a highly porous carbon material with magnetic properties

Russian Journal of Applied Chemistry - Double modification of birch wood sawdust was performed with the aim to prepare porous carbon materials with magnetic properties.     

Spreading and recoil of a surfactant-containing water drop on glass-supported alcohol films

In this paper we report the experimental observation of spreading and recoil of surfactant-containing water drops on various alcohol films supported on glass slides. The time evolution of spreading and recoil behavior was recorded by placing a web camera above the drop. We observed that the drop spread the fastest on CH3OH, followed by C2H5OH, and the slowest on i-PrOH. On the other hand, the recoil behavior was just the opposite. The drop recoiled the slowest on CH3OH and fastest on i-PrOH, while it recoiled in an intermediate time on C2H5OH. In addition, concentration of surfactant in the drop played a prominent role in the spreading and recoil time of the drop, with higher surfactant concentration making the drop spread and recoil faster. The time evolution of spreading velocity of the drop on different alcohol films at various surfactant concentrations occurred with a Gaussian distribution and the peak velocity was reached earliest on CH3OH followed by C2H5OH, while on i-PrOH it took the longest time. The recoil behavior was similar. The variation of velocity as a function of radius exhibited oscillatory behavior, indicating the existence of an interfacial phenomenon. We also report the observation that spreading of the drop occurred without observable fingering instability. Further, we observed by Fourier transform infrared (FTIR) spectroscopic measurements that the drop had mixed with the alcohol films as it spread. Miscibility of the alcohol in the film with the drop, alcohol evaporation cooling-induced temperature gradient, and Marangoni effect probably play important roles in the spreading and recoil behavior of the drop.     

Silver CD-R based substrate as a SERS active material

A silver Compact Disc Recortable (CD-R) based substrate has been proposed as an alternative to silver colloids as active material successfully used in surface-enhanced Raman spectroscopy (SERS). Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray Spectroscopy (EDXS) measurements revealed that silver nanoparticles are present over the entire surface of the uncovered reflective layer of commonly used CD-R. The process of preparation of the CD-R based surface is simple, fast and repeatable. Recorded Raman spectra of 10 µM Rhodamine 6G applied to the substrate corroborate strong enhancement of Raman signal. The maximum value of EF was calculated to be about 5.76 × 10⁶. Raman maps are consistent with SEM micrographs and confirmed the presence of a numerous SERS hot spots occurring on the trucks of CD-R based substrate.     

Impregnated active carbons to control atmospheric emissions. 2. Influence of the raw material on the porous texture

The preparation of impregnated active carbons was optimized, in order to use them as catalysts for the deep oxidation of volatile organic compounds on atmospheric emissions. When impregnation is performed on the raw material or after activation, the influence of raw material on the texture and on the catalyst dispersion is already well studied. This paper aims to analyze the influence of raw material when the impregnation step is performed after the carbonization of different carbon precursors, as yet knowledge is very scarce. Olive stones, pinewood sawdust, nut shells, and almond shells were used as raw materials. In order to evaluate the influence of impregnation methodology of CoO, Co(3)O(4), and CrO(3) on the catalyst dispersion in the porous carbon texture, the impregnation step was made after activation and between carbonization and activation. On the first sequence, for all the raw materials, the impregnated oxides must be deposited on the internal surface, blocking part of the initial porous texture. When the impregnation step is conducted after carbonization, metal species act as catalysts during the activation step. The textures developed strongly depend either on the raw material or on the chemical state and distribution of the catalyst in the carbonized material. Olive stones and sawdust carbons stay with a microporous texture with very narrow pores where catalysts are not deposited. In nut shell and almond shell carbons, metal species are dispersed in the largest micropores and in a well-developed mesoporous texture.     

A heterometallic porous material for hydrogen adsorption

Two kinds of heterometallic complexes, {[Sm2(L)6Co2][Co(H2O)6].3H2O}n (Sm-Co) and {[Sm2(L)6Zn3(H2O)6].1.5H2O}n (Sm-Zn) (H2L=oxydiacetic acid), were synthesized under hydrothermal conditions. In Sm-Co, each L chelates to one Sm3+ center and bonds to two Co2+ ions in an anti-anti configuration. Sm and Co atoms are arrayed alternatively and connected by O-C-O bridges to form a cubic octahedral cage as the secondary building unit. Consequently, topological NaCl nets with high symmetry in the cubic space group Fdc have been constructed. It is interesting to note that Sm-Co contains interesting 2-fold interpenetrating 3D hydrogen-bonding supramolecular networks while in Sm-Zn each L adopts a syn-syn configuration to link two Zn2+ ions. Carboxylate groups bridge adjacent Sm and Zn atoms to create two kinds of metallocycles, Sm2(COO)4Zn2 and Sm6(COO)12Zn6, to be further assembled into a highly ordered 3D nanotubular structure. Sm-Zn represents the largest porous material among the heterometallic coordination polymers and the first example in the investigation of hydrogen adsorption. Sm-Zn possesses hydrogen storage capacity of up to 1.19 wt % at 77 K and 0.54 wt % at 298 K, respectively.     

Estimation of the porous structure of active carbons

Active carbons from apricot, plum, peach, and grape stones were prepared. The analysis of adsorption isotherms of benzene vapor showed that the active carbons obtained from fruit stones have highly homogeneous microporous structures withW ₀ 0.30 cm³ g^–1,E ₀ 24.5 kJ mol^–1, andx ₀ 0.42 nm, and they contain ultramicropores along with micropores.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1934–1936, October, 1995.This study was financially supported by the Russian Foundation for Basic Research (Project No. 94-03-09550).     

Manipulating the cavity of a porous material changes the photoreactivity of included guests

Changing an ether to a ketone within the framework of a bis-urea macrocycle has little effect on the supramolecular assembly of this building block into porous crystals but introduces a triplet sensitizer into the framework that dramatically alters the photochemical reactions of included guests.     

Electrical conductivity in a non-covalent two-dimensional porous organic material with high crystallinity

Electroactive macrocycle building blocks are a promising route to new types of functional two-dimensional porous organic frameworks. Our strategy uses conjugated macrocycles that organize into two dimensional porous sheets via non-covalent van der Waals interactions, to make ultrathin films that are just one molecule thick. In bulk, these two-dimensional (2D) sheets stack into a three-dimensional van der Waals crystal, where relatively weak alkyl–alkyl interactions constitute the interface between these sheets. With the liquid-phase exfoliation, we are able to obtain films as thin as two molecular layers. Further using a combination of liquid-phase and mechanical exfoliation, we are able to create non-covalent sheets over a large area (>100 μm²). The ultrathin porous films maintain the single crystal packing from the macrocyclic structure and are electrically conductive. We demonstrate that this new type of 2D non-covalent porous organic framework can be used as the active layer in a field effect transistor device with graphene source and drain contacts along with hexagonal boron nitride as the gate dielectric interface.

Ultrathin porous films held together by non-covalent van der Waals interactions was obtained by a top-down approach, which is then utilized as channel material in a two-dimensional planar field-effect transistor device through easy stamp transfer.

We describe a new type of two-dimensional (2D), molecularly-thin porous organic framework that is formed from macrocyclic building blocks that assemble, through non-covalent interactions, into a porous two-dimensional plane. Covalent organic frameworks (COFs) are promising in applications due to their ability to host other functional molecules in the voids.^1–7 Many porous frameworks have been demonstrated to be useful in energy storage,⁸ catalysis,^9–11 separation,^12,13 optoelectronics^4,14 and sensing.^15,16 In order to construct nanodevices with porous channels, ultrathin films of porous frameworks has been prepared with bottom-up^4,17–20 and top-down^1,21 approaches. The top-down approaches to these materials are enabled by strong covalent bonds in the two-dimensional plane and weak van der Waals interactions between them, similar to what is seen in two-dimensional materials such as graphene and TMDs.^22–27 For porous ultrathin films, the electrical conductance has not been extensively investigated.^2,7,20,28,29Here, we explore making molecularly thin layers in which conjugated macrocycles are used as building blocks and non-covalent van der Waals interactions are the adhesive that assembles these molecules into rigid, porous layers. By adjusting the relative strengths of the interactions that direct the assembly within the plane and those holding the two-dimensional layers with respect to each other, we can exfoliate these non-covalent porous frameworks using the same means employed for traditional two-dimensional van der Waals materials.³⁰ Using liquid-phase and mechanical exfoliation, we create porous films that are as thin as two-layers of molecules. These new results are exciting and useful because previously we were not able to obtain such high-ordered thin porous film directly from its bulk crystal and were limited to investigating the electronic properties of this hollow organic capsules in spin-coated films. These ultrathin porous films are ordered over large areas and maintain the single crystal packing from the macrocyclic building blocks. To demonstrate the utility of this new type of ultrathin material, we fabricated 2D field effect transistor (FET) devices in which graphene is the source/drain contacts, hexagonal boron nitride is the gate dielectric interface, and the exfoliated molecular sheet is the active layer. These ultrathin self-assembled materials are efficacious at transporting electrons and will find utility in gas sensing and applications similar to traditional two-dimensional materials. Fig. 1 displays the molecular building block (1). Characterization is contained in the ESI^† and a previous report.³¹1 has several important molecular features in its solid-state assembly. It is a rigid and shape persistent macrocycle that has an interior and an exterior (Fig. 1a), and in bulk, has a pore of ∼11.4 Å in diameter and a surface area of 20 m² g⁻¹ from BET measurements.³¹ When it assembles in the crystalline state, it forms two-dimensional porous sheets with two types of cavities (Fig. 1b), one molecule thick, that are held together by relatively strong π–π contacts and Br–PDI interaction between the bromine atoms on the thiophenes and adjacent PDI molecules (Fig. 1c), which plays a crucial role in the self-assembly of the films. The close proximity of the molecules in the 2D plane together with the conjugation within the macrocycle facilitate charge transport of electrons in the 2D plane. These electrically conductive porous sheets then stack into a three-dimensional crystal in which adjacent sheets are separated from one another by the alkane sidechains of the perylene diimide (Fig. 1d). It is in this alkane gallery that we see an opportunity for exfoliation to yield ultrathin 2D sheets.Open in a separate windowFig. 1Structure and packing of molecule 1. (a) Chemical structure, side view and top view of molecular structure of 1. C, N, O, S, Br are colored in grey, blue, red, yellow and green, respectively. The vertical distance of one macrocycle is about 1.5 nm. (b) Face-on view and edge-on view of one layer of 1. The internal cavity of 1 and the cavity formed by the packing of 1 are labeled as i and i′, respectively. (c) Interactions binding two adjacent macrocycles from neighboring brominated thiophene rings. (d) View of packing of 1 along the c axis through the interaction of alkane sidechains. Exfoliation takes place at the alkyl–alkyl interface. One layer of 1 is about 2 nm in thickness.We isolated crystals of this material that were grown from solution and then tested whether they can be exfoliated. Fig. 2a displays a representative micrograph of one of the crystals. The crystal has a pseudo-hexagonal packing of the molecular building blocks in the two-dimensional plane, and this symmetry is mirrored in the hexagonally-shaped crystals. The simplest method for exfoliation is mechanical exfoliation, which is most commonly performed using scotch-tape.^32,33 We place the single crystals onto clean scotch-tape and repeat the mechanical exfoliation process for a few repetitions, and then we transfer the exfoliated crystals onto a clean silicon wafer. Fig. 2b displays an atomic force microscopy (AFM) micrograph of the typical non-covalent porous 2D sheet of 1 we obtained from this method. The porous sheets are flat and smooth and a few micrometers in diameter with a thickness of ∼8 nm; this thickness corresponds to a stack of five molecular layers of 1. This result demonstrates that non-covalent interactions are strong enough to hold molecules together to form ultrathin porous materials. Just as with traditional two-dimensional materials, the non-covalent porous organic 2D sheets of 1 are flexible as evidenced by the wrinkles and folds in the micrograph in Fig. 2b and S2.^†Open in a separate windowFig. 2Mechanical exfoliation of 1. (a) Optical microscopy and scanning electron microscope (SEM) (inset) images of a single crystal of macrocycle 1. (b) AFM and optical microscope (inset) images of the ultrathin non-covalent porous sheet of 1 on a silicon wafer obtained from mechanical exfoliation.We were unable to obtain porous films as thin as a single layer and also large-area samples using mechanical exfoliation, and thus we next explored if liquid-phase exfoliation^34,35 could produce them. Because the halogen bonds that hold the sheets together should be most robust in solvents with a low-dielectric constant that lack heteroatoms, and because the groups holding the sheets together are the alkane sidechains, we chose saturated hydrocarbons (hexane or heptane) as the solvents for exfoliation. Fig. 3a shows the process we follow for the liquid-phase exfoliation. We suspend single crystals of 1 in heptane and sonicate the mixture for five minutes. We drop cast the supernatant solution on silicon wafer and examine them with AFM. Remarkably, we are able to obtain non-covalent porous organic frameworks as thin as only two molecular layers (Fig. 3b).³⁶ Nevertheless, the lateral size of the porous 2D sheets of 1 we could obtain using this method are quite small, making it difficult to fabricate devices from them.Open in a separate windowFig. 3Liquid-phase exfoliation and combination of liquid-phase and mechanical exfoliation. (a) Schematic showing the liquid-phase exfoliation process. (b) AFM image of the ultrathin sheet of 1 on a silicon wafer obtained from liquid-phase exfoliation method. The sheets in this micrograph are two molecular layers (left) and three molecular layers (right) in thickness. (c) AFM image of the ultrathin sheet of 1 on a silicon wafer obtained from combination of liquid-phase and mechanical exfoliation, inset: optical microscope image of the ultrathin sheet 1. (d) AFM image showing the height change across the ultrathin sheet of 1 on silicon wafer obtained with combination methods, inset: optical microscope image of the ultrathin sheet of 1.To get large-area films characteristic of the mechanical exfoliation and thin films characteristic of the liquid-phase exfoliation, we combined the two methods. We first immerse the crystal of 1 in heptane for a few minutes to let the solvent seep into the gallery between the sheets and weaken the interlayer interactions. Then, we use mechanical exfoliation to isolate the ultrathin films. With this method, we obtained sheets of 1 with a lateral size of over ten micrometers, as shown in Fig. 3c. By carefully examining the exfoliated non-covalent porous 2D sheets of 1, we were also able to observe the height change across the sheet (Fig. 3d) with integer values of the layer thickness after the exfoliation steps. As marked red in Fig. 3d, we could identify a single layer of 1 with a height difference between these two surfaces of about 1.5 nm, corresponding to monolayer of molecule 1.We conducted transmission electron microscopy (TEM) studies to characterize the crystallinity of the as-prepared non-covalent porous 2D sheets of 1. As shown in Fig. 4a (inset), the 2D sheets exhibit a layered structure after liquid-phase exfoliation. The selected area electron diffraction (SAED) in the area (marked by the red circle) reveals a hexagonal diffraction pattern, with the bright reflections corresponding to the (2 1(−) 0) plane, with a spacing of 11.3 Å. This diffraction pattern confirms that the non-covalent, porous 2D sheets of 1 retain the single crystal packing and are stable to the liquid-phase processing.Open in a separate windowFig. 4TEM characterization and device fabrication. (a) SEAD pattern and TEM image (inset) of the non-covalent porous ultrathin sheet 1 obtained by liquid-phase exfoliation. (b) Schematic showing the structure of the hBN/Graphene/1 device based on the non-covalent porous ultrathin sheet 1 with graphene as electrodes and hBN as the dielectric layer. (c) Optical microscope image showing the as-fabricated hBN/Graphene/1 device. (d) Transfer curve of the hBN/Graphene/1 device.We next sought to determine the ability of these non-covalent porous ultrathin layers to transport charge. Because these films are van der Waals materials, we sought to make devices with van der Waals interfaces. [The ESI^† contains the current/voltage curves for 1 in a more traditional organic FET with Au contacts and trichloro(octadecyl)silane coated SiO₂ as the gate dielectric.] The source-drain contacts were fabricated from graphene and the dielectric interface was hexagonal boron nitride (hBN). A schematic of the device is shown in Fig. 4b. To create this device, we first exfoliate graphene and hBN onto a silicon substrate. We then follow a published procedure³⁷ to first pick up hBN and then graphene to make the hBN/graphene stack. We transfer this hBN/graphene stack onto another clean silicon substrate. Then the graphene was cut using electron beam lithography and an oxygen plasma to open a 300 nm gap between graphene electrodes (see Fig. S4^† for the AFM details of graphene electrodes). In order to transfer the non-covalent porous ultrathin sheets of 1 onto the graphene electrodes, we exploit the combined liquid/mechanical exfoliation method above to obtained 2D sheet of 1 with polydimethylsiloxane (PDMS) polymer as the substrate, which was then used for the stamp transferring. In this manner, we were able to transfer the ultrathin sheets (∼20 nm) onto the graphene electrodes. Fig. 4c displays the optical microscope image of the device, and Fig. 4d displays the FET transfer curves revealing that the material is an efficacious, n-type transistor. Several features of the device are noteworthy. The electron mobility in the linear regime was estimated to be 1.6 × 10⁻⁴ cm² V⁻¹ s⁻¹ from the transfer curve. As expected, it is somewhat lower than the electron mobility estimated from the saturation regime of the traditional OFET shown in Fig. S3.^†38 Despite the small size and the nanoscale thickness, the material exhibits over 3 orders of magnitude difference in current between the off and on state of the device. The threshold voltage is about 39 V, implying that the device turns on at relatively high voltage. We surmise that the contact, through the alkane sidechains is an impediment to more efficient charge transport.     

Reversible and selective O2 chemisorption in a porous metal-organic host material

The metal-organic host material [{Co(III)(2)(bpbp)(O(2))}(2)bdc](PF(6))(4) (1·2O(2); bpbp(-) = 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato; bdc(2-) = 1,4-benzenedicarboxylato) displays reversible chemisorptive desorption and resorption of dioxygen through conversion to the deoxygenated Co(II) form [{Co(II)(2)(bpbp)}(2)bdc](PF(6))(4) (1). Single crystal X-ray diffraction analysis indicates that the host lattice 1·2O(2), achieved through desorption of included water guests from the as-synthesized phase 1·2O(2)·3H(2)O, consists of an ionic lattice containing discrete tetranuclear complexes, between which lie void regions that allow the migration of dioxygen and other guests. Powder X-ray diffraction analyses indicate that the host material retains crystallinity through the dioxygen desorption/chemisorption processes. Dioxygen chemisorption measurements on 1 show near-stoichiometric uptake of dioxygen at 5 mbar and 25 °C, and this capacity is largely retained at temperatures above 100 °C. Gas adsorption isotherms of major atmospheric gases on both 1 and 1·2O(2) indicate the potential suitability of this material for air separation, with a O(2)/N(2) selectivity factor of 38 at 1 atm. Comparison of oxygen binding in solution and in the solid state indicates a dramatic increase in binding affinity to the complex when it is incorporated in a porous solid.     

The effect of active component distribution in a porous structure of supported catalyst

The catalytic process in supported catalyst with nonuniform distribution of active component among the pores of different size is considered. Some previous as well as new estimates are presented. The limit value of diffusivity in small pores (D _L < 10^?8 cm²/s) is established, at which the distribution can takes an effect. That is possible in the case of capillary condensation, when micro-pores are filled with liquid while macro-pores are filled with gas. Such diffusivity is also observed at configuration or surface diffusion in zeolite channels. Then the distribution may influence the pellet effectivity when the activity of active component inside zeolite crystals is higher than that on its external surface.     

A capillary gas chromatographic column with a porous layer based on a mesoporous material

A procedure for synthesizing an MSM-41-type mesoporous mesophase material (MMM) layer, that is, a layer of a solid porous material with a regular arrangement of nanoscale calibrated pores and a unified geometry, on the inner wall of a capillary column was developed. Because of the high specific surface area of silica, capillary columns with a porous MMM layer on the basis of silica allow the amount of samples introduced to be increased by an order of magnitude compared with the known capillary porous-layer columns. An example of the separation of light hydrocarbons is described. The properties of columns with MMM porous layers are discussed.     

Solid-state fluorescence study of naphthalene adsorption on porous material

Naphthalene adsorption profile on porous materials was studied using solid-state fluorescence spectroscopy. When naphthalene crystals were simply mixed with porous crystalline cellulose (PCC), excimer emission of naphthalene was observed after 1 min of mixing, suggesting a drastic change in the naphthalene molecular environment during the mixing procedure. For the naphthalene-octadesyl silane (ODS)-80A or naphthalene-ODS-2 systems, the changes in adsorption profiles and fluorescence spectral pattern of naphthalene were similar to those of the naphthalene-PCC system. The final amounts of naphthalene adsorbed to ODS-80A and ODS-2 were 0.05 and 0.024 g/g adsorbent, respectively, even though the two materials had comparable values of specific surface area. The relative emission intensity (I(excimer)/I(monomer)) in the ODS-80A system was higher than that in the ODS-2 system when compared at the same amount of naphthalene adsorbed. It was concluded that the pore size of porous materials affected the naphthalene excimer formation on the surface.     

Rational design of a novel two-dimensional porous metal-organic framework material for efficient benzene sensor

As a common volatile organic compound, benzene (C₆H₆) exists in home decoration pollution gas widely, which causes great harm to the environment and human health. Therefore, it is necessary to rationally design advanced materials with high selectivity to detect and capture C₆H₆. Herein, combined with the d-band center theory and cohesive energy, a new two-dimensional metal-organic framework material, Ni-doped hexaaminobenzene-based coordination polymer (Ni-HAB-CP) is designed, and its application potential as a C₆H₆ sensor are systematically investigated by using first principles calculation. The result shows that Ni-HAB-CP has a strong adsorption for C₆H₆ without any additional method. In addition, Ni-HAB-CP can maintain good conductivity before and after adsorption, and C₆H₆ can be easily desorbed from the surface of Ni-HAB-CP by charge control. Moreover, the I-V curve calculated by Atomistix Toolkit (ATK) reveals that Ni-HAB-CP has high sensitivity and selectivity to C₆H₆. Hence, Ni-HAB-CP is expected to be used as a potential material for a highly efficient and recyclable C₆H₆ sensor in the future. The calculation and analysis methods used in this paper could provide a certain theoretical basis and reference for the future research of gas sensors.     

Mathematical models of the nickel hydroxide active material

A review is presented of the mathematical models that have been developed to describe the phenomena that occur in the active material in the nickel electrode. The review includes models that describe the reaction thermodynamics, proton diffusion, electron conductivity, semiconductor effects, and the reactions in the solid phase. The appropriateness of these models and their usefulness in predicting phenomena observed in nickel-based batteries are discussed. Received: 17 October 1999 / Accepted: 26 December 1999     

Palladium hydrogenation catalyst based on a porous carbon material obtained upon the dehydrochlorination of a chloro polymer

The applicability of a porous carbon material obtained as a result of the “chemical” dehydrochlorination of chlorinated polyvinyl chloride as a support for palladium hydrogenation catalysts was demonstrated. The efficiency of the catalyst was evaluated in the liquid-phase reactions of nitrobenzene hydrogenation and chlorobenzene hydrodechlorination. Although the specific activity of the catalyst was lower by a factor of 3–4 than that of the samples based on Sibunit and carbon nanotubes, the complete conversion of the initial compounds with the selective formation of end products under mild conditions was achieved at a relatively low palladium content (1.5%).     

Liquid-solid phase transformation of potassium iodide aqueous solutions of different concentrations held inside a porous material

Calorimetric analysis shows a succession of transformations inside and outside the pores, whose characteristics depend on the concentration of the solution and the amount of porous body present.For a given porous body, whatever the initial concentration of the solution, the capillary condensate concentration evolves systematically, during cooling, towards the eutectic concentration even if the initial salt concentration is higher than the eutectic one. It should be noted that this phenomenon indicates migration outside the pores of water or potassium iodide according to the initial concentration.For various samples whose pore size is decreasing, successive solidification of divided water and eutectic occurs at decreasing temperatures. The freezing temperature depression of water in divided KI solutions does not seem to be a function of the salt concentration but is dependent mainly on the division effect. A nearly linear relationship between pore radius and the reciprocal of temperature depression may experimentally be established for divided eutectic.

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Zusammenfassung Kalorimetrische Analyse zeigt eine Reihe von Umwandlungen inner- und außerhalb von Poren, wobei die Charakteristik der Umformungen von der Konzentration der Lösung sowie von der Menge des anwesenden porösen Körpers abhängt. Bei einem gegebenen porösen Körper verändert sich die Konzentration des Kapillarkondensates unabhängig von der Ausgangskonzentration systematisch immer in Richtung der eutektischen Konzentration, auch wenn die Salzkonzentration zu Beginn über der eutektischen Konzentration liegt. Man muß bemerken, daß diese Erscheinung je nach Ausgangskonzentration auf Migration von Wasser oder Kaliumjodid außerhalb der Poren hinweist.Für verschiedene Proben mit abnehmender Porengröße findet bei sinkender Temperatur ein nacheinanderfolgendes Erstarren von getrenntem Wasser und Eutektikum statt. Die Gefrierpunktserniedrigung von Wasser in derartig getrennten KI-Lösungen scheint nicht eine Funktion der Salzkonzentration zu sein sondern hauptsächlich vom Separierungseffekt abzuhängen. Für unterteilte Eutektika konnte ein annähernd linearer Zusammenhang zwischen dem Porenradius und dem Reziproken der Temperaturerniedrigung festgestellt werden.