Electrohydrostatics of capillary switches

A capillary switch is a system of two liquid drops, one sessile and the other pendant, obtained by overfilling a hole of radius R in a plate. When surface tension dominates gravity, the equilibrium shapes of the drops are spherical sections of equal radii. If the combined volume of the top V_T and bottom V_B drops exceeds , the system has three equilibrium states of which two are stable. This bistability is exploited in applications by toggling the system between its two stable states. Here, we examine the effectiveness of using an electric field for toggling. Bifurcation diagrams are obtained that depict how the system's response varies with applied field strength E, and show loss of stability at turning points and the possibility of hysteresis. A phase diagram in space is presented to readily infer when an electric field is an effective means for toggling. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1451–1459, 2014     

The structure and photocatalytic performances of mechanically synthesized poly(3′,4′‐ethylenedioxy‐2,2′:5′,2″‐Terthiophene)/Zno composites

Poly(3′,4′‐ethylenedioxy‐2,2′:5′,2″‐terthiophene)/ZnO(poly(TET)/ZnO) composites with the ratio of poly(TET) and nano‐ZnO from 3:1 to 1:3 were synthesized by hand grinding and ball milling methods, respectively. The photocatalytic activities of the composites were examined through the degradation processes of methylene blue (MB) solution under UV light irradiation, and the possible mechanism for the photocatalytic activity enhancement by synergetic effects between nano‐ZnO and poly(TET) was proposed. The results showed that the strong interactions between the poly(TET) and nano‐ZnO occurred in the case of ball milling method. The results also proved that the crystallinity of ZnO was not disturbed in both of methods, and the nano‐ZnO was uniformly distributed in polymer matrix in the case of ball milling method. The comparative studies showed that the addition of the nano‐ZnO could enhance the photocatalytic activities of the composites. The highest degradation efficiency (100%) at 3 h under UV light irradiation occurred in the case of poly(TET)/ZnO(1:1) synthesized by ball milling method. Furthermore, the nanocompsosite displayed higher photocatalytic activity than nano‐ZnO, which was due to the holes (h⁺) transferring from the valence band of ZnO to the polymer backbone and the adsorption of MB molecules in polymer matrix via π–π conjugation between MB and aromatic regions of the poly(TET). POLYM. COMPOS., 36:1597–1605, 2015. © 2014 Society of Plastics Engineers     

Actor networks and the construction of applicable knowledge: the case of the Timbre Brownfield Prioritization Tool

This article deals with experiences acquired during the process of developing the Timbre Brownfield Prioritization Tool (TBPT). Developing a decision support tool that takes into account the expectations and experiences of its potential users is similar to creating applicable knowledge by the joint action of scientists and heterogeneous actors. Actor network theory is used to explore the construction of this form of applicable knowledge as a process of actor network creation. Following the French sociologist Callon, networks are seen to be initiated and carried out by a group of scientists (tool developers) via four moments of translation, called problematization, interessement, enrolment and mobilization. Each step in the construction of the TBPT—from the initial research question to the final model—can be linked in retrospect to changing configurations of actor networks. Based on the experiences of the tool developers in the Czech Republic, Poland, Germany and Romania, we illustrate how these configurations varied across space and time. This contribution emphasizes the ability to correlate gains in knowledge with the more visible changes in the scope of actor networks in order to highlight achievements but also limitations in acquiring applicable knowledge.     

Estimating the uniaxial compressive strength of pyroclastic rocks from the slake durability index

Because the preparation of standard samples may not always be possible for weak or soft rocks, the prediction of uniaxial compressive strength (UCS) from indirect methods is widely used for preliminary investigations. In this study, the possibility of predicting UCS from the slake durability index (SDI) was investigated for pyroclastic rocks. For this purpose, pyroclastic rocks were collected from 31 different locations in the Cappadocian Volcanic Province of Turkey. The UCS and SDI tests were carried out on the samples in the laboratory. The UCS values were correlated with the SDI values and a very strong exponential relation was found between the two parameters. Since some data were scattered over the UCS values of 20 MPa, the correlation plot was redrawn for above and below the UCS values of 20 MPa, respectively. Very strong linear correlations were developed for two cases. Our concluding remark is that the UCS of pyroclastic rocks can be estimated from the SDI.

     

Electrochemical and spectroscopic characterization of a Benzo[c]cinnoline electrografted platinum surface

In this work, a platinum surface was modified with benzo[c]cinnoline (BCC) to get new insight into the metal modification area. By potential scanning from + 0.4 V to - 0.8 V, the diazotized BCC was reduced electrochemically and grafted onto the platinum electrode surface to form benzo[c]cinnoline modified platinum electrode (Pt-BCC). Electrochemical reduction of benzo[c]cinnoline diazonium salt on the electrode surface yielded a relatively stable organic film. The introduction of BCC molecules onto the platinum surface was verified by cyclic voltammetry, electrochemical impedance spectroscopy, Raman spectroscopy and ellipsometry. The stability and the potential range of the Pt-BCC electrode were also studied.     

Influence of the harvesting year and fertilizer on the fatty acid composition and some physicochemical properties of linseed (Linum usitatissimum L.)

Sar? 85 (Linum usitatissimum L.) linseed variety was used in this study. Linseed was cultivated at 2008 (LS-08) and 2009 (LS-09) without fertilizer. In addition, at 2009 diammonium phosphate [(NH₄)₂HPO₄] and ammonium nitrate (NH₄NO₃) were applied (LSF-09). The linseeds were analyzed for protein, ash and oil contents and fatty acid compositions. There were differences among harvesting years for oil, protein and ash contents of the seeds. The greater oil and protein contents were obtained during LS-08 compared with LS-09. There were no significant difference in protein and ash content between LS-09 and LSF-09 while a significant difference was observed in oil content. Seed protein, oil and ash contents were significantly affected by the harvesting year, but only oil content was affected by the fertilizer treatment. There are significant differences in palmitic, stearic, oleic, ??-linolenic and arachidic acid between LS-08 and LS-09. While palmitic, stearic, oleic acid decreased, ??-linolenic and arachidic acid increased during 2009 harvesting year. LSF-09 has the highest amount of ??-linolenic acid. The fertilizing treatment seems to have an increasing effect on the amount of ??-linolenic acid, while it has a decreasing effect on the oleic acid content.     

Biodiversity and technological properties of yeasts from Turkish sourdough

Food Science and Biotechnology - In this study, yeasts were isolated and characterized from twelve traditional sourdough samples which belongs to Black Sea and Aegean regions of Turkey. Twenty six...     

Selective separation of cobalt and nickel by supported liquid membranes

The selective separation of cobalt from acidic media, containing both equimolar and nonequimolar mixtures of cobalt and nickel, was examined by supported liquid membranes using Alamine 336 as mobile carrier dissolved in various diluents. The membrane support was microporous hydrophobic polypropylene Celgard 2500 (25 μm thick, 0.209 × 0.054 μm pore size and 55% porosity). Acetic acid-Na acetate buffer was used for the adjustment of the feed pH which was critical. Various parameters were experimentally studied and the optimum conditions were determined.     

Cooperative communications with multilevel/AES-SD4-CPFSK in wireless sensor networks

In this paper, a new joint multilevel data encryption and channel coding mechanism is proposed, which is called ??multilevel/advanced encryption standard?Csystematic distance 4?Ccontinuous phase frequency shift keying?? (ML/AES-SD4-CPFSK). In the proposed scheme, we have not only taken advantage of spatial diversity gains but also optimally allocated energy and bandwidth resources among sensor nodes as well as providing high level of security and error protection for cooperative communications in wireless sensor networks. Relay protocols of cooperative communications, such as amplify-and-forward and decode-and-forward with/without adversary nodes, have been studied for 4CPFSK, 8CPFSK, and 16CPFSK of ML/AES-SD4-CPFSK. We have evaluated the error performances of multilevel AES for data encryption, multilevel SD-4 for channel coding, and various CPFSK types for modulation utilizing cooperative communications in wireless sensor networks. According to computer simulation results, significant diversity gain and coding gain have been achieved. As an example, bit error rate (BER) performance of 10^?5 value has been obtained at a signal-to-noise ratio (SNR) of ?6?dB for SD-4-CPFSK scheme in a compared related journal paper, whereas in our proposed system, we have reached the same BER value at a SNR of ?23?dB with amplify-and-forward with direct path signal protocol in 16-level AES, two-level SD-4 coded 16CPFSK, and at the same time, we have reached the same BER value at a SNR of ?22?dB with amplify-and-forward without direct path signal protocol in 16-level AES, two-level SD-4 coded 16CPFSK.     

Numerical Study on Heat Transfer Between Turbulent Flow and Porous Rectangular Cylinders with Uniform Injection or Suction

The heat transfer characteristics of the flow around rectangular cylinders having various aspect ratios with uniform injection or suction through the rear, top, bottom, and all surfaces have been studied numerically. The effects of injection or suction on heat transfer have been linked to the analysis via wall functions of the velocity and temperature sublayers. The computational code employed in the present study was verified with a typical benchmark problem of the flow around a square cylinder. The results show that the heat transfer between the main flow and rectangular cylinders is substantially influenced by injection or suction—that is, suction enhances the heat transfer, while injection through the rear surface provides some thermal protection.