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Bound Around Download [PORTABLE] Free

Our software library provides a free download of Bound Around 1.4. The software lies within Games, more precisely Puzzle. Our built-in antivirus checked this download and rated it as virus free. The current installer available for download occupies 2 MB on disk. The most popular versions of the software are 1.4 and 1.0. This software is a product of K.Hofer. Commonly, this program's installer has the following filename: BoundAround.exe.

Bound Around download free

Knowledge on moisture transport in wood is important for understanding its utilization, durability and product quality. Moisture transport processes in wood can be studied by Nuclear Magnetic Resonance (NMR) imaging. By combining NMR imaging with relaxometry, the state of water within wood can be identified, i.e. water bound to the cell wall, and free water in the cell lumen/vessel. This paper presents how the transport of water can be monitored and quantified in terms of bound and free water during water uptake and drying. Three types of wood from softwood to hardwood were selected covering a range of low to high density wood; pine sapwood and oak and teak. A calibration is performed to determine the different water states in each different wood type and to convert the NMR signal into moisture content. For all wood types, water transport appeared to be internally limited during both uptake and drying. In case of water uptake, free water was observed only after the cell walls were saturated with bound water. In case of drying, the loss of bound water starts only after vanishing of free water, irrespective of the position. Obviously, there is always a local thermodynamic equilibrium of bound and free water for both uptake and drying. Finally, we determined the effective diffusion coefficient (D eff ). Experimentally determined diffusion constants were compared with those derived by the diffusion models for conceptual understanding of transport mechanism. We found that diffusion in the cell wall fibers plays a critical role in the transport process.

In wood, water can be present in two states. First, the water can reside in cell walls, which is called bound water. Second, water may exist in liquid pockets located in the cell lumen and other void spaces, called free water. Generally, one can observe a transition from a regime where only bound water is present towards a regime where free and bound water are present together. The point where this transition occurs is called the Fiber Saturation Point (FSP) (Stamm 1971). Understanding the transport properties requires understanding the changes in bound and free water (Topgaard and Söderman 2002). Although many studies have been performed to understand water transport properties, it is not easy to identify the state of water within wood, and especially to determine each state during uptake or drying by experimental techniques, such as weighing (Wiberg et al. 2000) or X-ray computer tomography (CT) (Sandberg and Salin 2010) or neutron radiography (Sedighi-Gilani et al. 2012).

In this work, we aim to visualize and quantify bound and free water distribution for pine sapwood, oak and teak during water uptake and drying by using NMR imaging and relaxometry. More specifically, five subsequent steps are taken to answer to this objective. The first step is to discriminate between bound and free water in the measured signal, i.e. to calibrate the signal. The second step is to convert the NMR signal into moisture content. In the third step we monitor and quantify the changes in bound and free water, and the order of filling/emptying of each state during uptake and drying, whereas in the fourth step the effective diffusion coefficient, D eff , is determined. Finally, in the fifth step these experimental D eff values are compared with those derived by two diffusion models.

As in the case I, when the moisture content (MC) is far below the FSP, the cell wall water is tightly bound to the hydroxyl groups of cellulose by hydrogen bonds along the chains of the amorphous or paracrystalline regions via reversible processes (Siau 1984). Note that the water does not penetrate into the crystalline regions of cellulose (Skaar 1988). It results in a relatively short relaxation time, called bound water. When the MC increases towards the FSP, as in case II, more water molecules with an increased mobility are present in the cell wall, resulting in a small increase in the short relaxation time. In fact, one can consider them as clusters of water that are still bound. It is hard to differentiate these two cases (I and II) by looking at T 2 values, since there may not be a significant difference. On the other hand, a signal increase is observed for case II due to an increase in hydrogen nuclei. When the MC increases above the FSP, as in case III, water will be present within the lumen having a longer relaxation time, called free water. Different T 2 values in the range of free water result from the presence of different sized lumen or other void spaces. For example, earlywood cells have wider lumen, so longer T 2, compared to latewood cells (Menon et al. 1987; Kekkonen et al. 2014). The wood cellulose has very short T 2 around tens of microseconds, which is too short to be observed in the used NMR set-up. The bound water in the cell wall has a T 2 typically ranging from hundreds of microseconds to several milliseconds, whereas the free water in the lumen has a T 2 typically ranging from ten to hundreds of milliseconds. Additionally, later studies showed an extra slow relaxing component in hardwood due the presence of vessel elements (Almeida et al. 2007; Passarini et al. 2014). The free water in vessels may have higher T 2 values compared to the water in lumen.

Compared to pine sapwood, the main difference is that the long relaxation time observed for the fully saturated sample has a very broad distribution ranging from 10 to 300 ms. The broad distribution reflects the polydispersity of the pore sizes. The short T 2 corresponding the bound state is around 1 ms for fully saturated sample, which decreases to lower values around 0.5 ms with decreasing RH till 33%. At 12 and 22% RH, T 2 is even shorter, being below 0.2 ms.

Comparing the relaxation times corresponding to bound and free water in pine sapwood and oak, there are additional peaks observed for teak. The relaxation time distribution ranging from 30 to 600 ms corresponds to the water in the free state, which is only available in the fully saturated sample. The relaxation time corresponding to bound water is around 3 ms in fully water saturated condition, around 2 ms for high RH (97%), and a shift towards lower values (around 0.5 ms) at relatively dry conditions. The additional peaks are observed between 4 and 30 ms, which seems similar at all RH. We separate the total signal intensity (SI) into the sections of the bound water (below 4 ms) and the additional peaks (between 4 and 30 ms) based on the relaxation analysis in Fig. 7, by summing up the signal intensities in the relative sections. In Fig. 8, the corresponding signal intensities of these two sections are shown versus RH. The gravimetrically determined sorption isotherm is also included in the graph.

The shape of the measured signal versus RH curve for the section below 4 ms is in agreement with the sorption isotherm. At very low RH (10%), NMR underestimates the amount of bound water as the T 2 is shorter than the echo time resulting in signal loss. For the section between 4 and 30 ms, the measured signal seems to be around 0.02, irrespective of the RH. This suggests the presence of a component in teak which is not influenced by the water content. It can be low-molecular-weight organic compounds known as extractives (Siau 1984; Peemoeller et al. 2013; Labbé et al. 2002).

a The MC profiles of pine sapwood during water uptake for 114 days. The profiles are given every 2 h for the first day and at the indicated times. b Moisture fraction of free water, θf, and bound water, θb, versus total MC at 3 positions: around 2 mm (top), 5 mm (middle) and 8 mm (bottom) below the surface

Besides the MC profiles, relaxation analysis is used to identify and quantify the state of water during water uptake. The relaxation analysis is performed at three different points, around 2 mm (top), 5 mm (middle) and 8 mm (bottom) below the surface, where it relates to a region of 0.5 mm width at each position. The plot of moisture fractions versus total MC at these three positions is given Fig. 10b. It shows that there is only bound water at initial stages. First the cell walls are filled with bound water, irrespectively of the position. Only after the saturation of the cell walls, free water is observed.

The MC profiles during water uptake of a oak, and c teak. The profiles are given every 2 h for the first day and at the indicated times. Moisture fraction of free water, θf, and bound water, θb, versus total MC for b oak, and d teak, at 3 positions: around 2 mm (top), 5 mm (middle) and 8 mm (bottom) below the surface

The plots of moisture fractions versus total MC at three different positions for both oak and teak are shown in Fig. 11b and d. At all positions, the bound water is first filled, and then free water is only observed after all the cell walls are saturated. The absence of free water before the cell wall saturation reveals a closed-pore system in all studied wood types. Since the fractions of bound and free water are dependent on the MC, intrinsically a thermodynamic equilibrium is set. Additionally for teak, the moisture fraction of bound water at full saturation of cell walls is around 15%, which is smaller than previously found FSP, 22%. It may result from the difference in the structure of this individual specimen, which differs from the average.


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