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Superelastic shape memory alloys (SMAs) are smart materials that can recover 6–8% elastic strains due to their phase transformation. SMAs also possess unique characteristics such as good energy dissipation, excellent re-centering capabilities and corrosion resistance. Recent studies have incorporated the use of superelastic SMA fibers in cementitious composites to achieve re-centering and crack-closing capabilities. Consequently, it is important to investigate the performance of fiber reinforced concrete (FRC) members under cyclic loading. This study investigates the use of hybrid steel/SMA fibers as reinforcement in concrete members subjected to cyclic flexural loading. Digital image correlation (DIC) was used to monitor the full field displacements and strains of the concrete beam specimens. Fiber density and statistical spatial point pattern functions were used to assess the fiber distribution. Two acoustic emission sensors were attached to each side of the concrete specimens to characterize crack development. A correlation between the crack width propagation and cumulative energy captured by the acoustic emission sensors was established. Results showed that the hybrid specimen with equal fiber volume ratios for steel and SMA fibers exhibit a lower mid-span deflection and smaller crack width. [ABSTRACT FROM AUTHOR]

Adsorption technologies provide high selectivity and low energy consumption making this technique very attractive to be employed in post-combustion carbon capture. In this publication, a material made of activated carbon and zeolite 13X is considered for a hybrid process termed Temperature Electric Swing Adsorption (T/ESA). This hybrid T/ESA can work as a traditional Temperature Swing Adsorption (TSA) heated by hot gas, but can also increase the temperature of the adsorbent very fast by Joule effect as long as the activated carbon provides a continuous conductive matrix for electricity. This paper discusses a detailed modeling of the T/ESA process when applied to three cases. The first case is the simulation of the T/ESA process with exhaust with 12% of CO 2 concentration, which has been chosen to validate the model against literature results. The second and third case studies consider the T/ESA application in a natural gas combined cycle (NGCC) traditional power plant, and in a NGCC plant with exhaust gas recycle (EGR). These cases were selected to investigate the adsorption technology at low CO 2 concentration and quantify the benefit of the EGR for carbon capture applications. Starting from an NGCC overall electric efficiency of 58.3% LHV based, the efficiency of the NGCC with T/ESA technology reduces to 35.3% while with EGR is 38.9% against the 49.9% with the MEA absorption plant. The same results are confirmed by the SPECCA index 13.05 MJ LHV /kg CO2 to 9.64 MJ LHV /kg CO2 against the reference of 3.36 MJ LHV /kg CO2 . The energy penalty of the T/ESA is significant because of electric consumptions required for the heating and fast cooling of the adsorbent. [ABSTRACT FROM AUTHOR]

Gonadotropin-inhibitory hormone (GnIH) has been characterized by its ability to inhibit either basal or gonadotropin-releasing hormone (GnRH)-induced gonadotropin synthesis and release in birds and mammals. However, the physiological role of GnIH on the reproductive axis in fish remains inconclusive, with most studies focusing on the orders Cypriniformes and Perciformes. To gain insight into the role of GnIH in the regulation of reproduction in the order Pleuronectiformes, we first cloned the LPXRFa gene, the piscine ortholog of GnIH, in the half-smooth tongue sole. The full-length cDNA of LPXRFa was 918 bp in size with an open reading frame (ORF) of 585 bp that encoded a 194 amino acids preprohormone with a calculated molecular mass and isoelectric point of 21.73 kDa and 6.52, respectively. The LPXRFa precursor encoded two putative peptide sequences that included –MPMRF or –MPQRF motifs at the C-terminal. Tissue distribution analysis showed that LPXRFa transcripts could be detected at high levels in the brains of both sexes and to a lesser extent in the ovary, heart and stomach of females, while a noteworthy expression was observed in the kidney and muscle of males. Furthermore, the expression patterns of LPXRFa mRNA during ovarian maturation were also investigated. In the brain, the mRNA expression of LPXRFa increased significantly at stage III, declined at stage V and reached a maximum at stage VI. In the pituitary, the levels of LPXRFa mRNA remained stable during ovarian maturation and increased significantly to the top level at stage V and then declined back to basal levels. In contrast, the ovarian LPXRFa mRNA levels declined sharply at stage III and remained depressed over the course of ovarian maturation. Taken together, our results provide further evidence for the existence of LPXRFa in the order Pleuronectiformes and suggest its possible involvement in the regulation of reproduction in the female tongue sole. [ABSTRACT FROM AUTHOR]

It is of great significance to provide theoretical guidance to the application of carbon nanotubes as adhesive materials via the investigation on their adhesion force. In this paper, molecular dynamics was adopted to investigate the adhesion force between the graphene substrate and the carbon nanotubes with varying deformation degrees and diverse types of irradiation induced defects at different temperatures. No obvious adhesion force was found between the carbon nanotube and graphene until the deformation degree of the former reached > 70%. The adhesion force would be maintained at a high level when the temperature was in the range of 280–320 K, which limited its application. Moreover, the adhesion force between carbon nanotube with vacancies and graphene substrate would decrease with increasing size of vacancies. Finally, compared with monovacancies and divacancies, Stone-Wales defects most remarkably reduced the adhesion force of carbon nanotubes. [ABSTRACT FROM AUTHOR]

Patterning strategies based on directed self-assembly (DSA) of block copolymers, as one of the most appealing next-generation lithography techniques, have attracted abiding interest. DSA aims at fabricating defect-free geometrically simple patterns on large scales or irregular device-oriented structures. Successful application of DSA requires to control and optimize multiple process parameters related to the bulk morphology of the block copolymer, its interaction with the chemical or topographical guiding pattern, and the kinetics of structure formation. Most studies have focused on validating DSA patterning techniques using PS- b -PMMA block copolymers as a prototypical material. As the development of DSA techniques advances, recent efforts have been devoted to extending the materials selection in order to fabricate more complex geometric patterns or patterns with smaller characteristic dimensions. How to select appropriate polymer materials in a vast parameter space is a critical but also challenging step. In this review, we discuss recent progress in the research of DSA of block copolymers focusing on three aspects: (i) screening the block copolymer materials, (ii) controlling the film properties, and (iii) tailoring the phase separation kinetics. [ABSTRACT FROM AUTHOR]

The molecular changes that allow plant roots to response to low phosphate levels are poorly understood. A series of three papers investigate this phenomenon and reveal which components of the auxin response are key for transmitting the phosphate signal into changes in root hair phenotypes. [ABSTRACT FROM AUTHOR]

The molecular mechanisms underlying age-related hearing loss are not fully understood, and currently, there is no treatment for this disorder. MicroRNAs have recently been reported to be increasingly associated with age-related diseases and are emerging as promising therapeutic targets. In this study, miR-34a/Sirtuin 1 (SIRT1)/p53 signaling was examined in cochlear hair cells during aging. MiR-34a, p53 acetylation, and apoptosis increased in the cochlea of C57BL/6 mice with aging, whereas an age-related decrease in SIRT1 was observed. In the inner ear HEI-OC1 cell line, miR-34a overexpression inhibited SIRT1, leading to an increase in p53 acetylation and apoptosis. Moreover, miR-34a knockdown increased SIRT1 expression and diminished p53 acetylation, and apoptosis. Additionally, resveratrol, an activator of SIRT1, significantly rescued miR-34a overexpression-induced HEI-OC1 cell death and significantly reduced hearing threshold shifts and hair cell loss in C57BL/6 mice after a 2-month administration. Our results support a link between age-related cochlear hair cell apoptosis and miR-34a/SIRT1/p53 signaling, which may serve as a potential target for age-related hearing loss treatment. [ABSTRACT FROM AUTHOR]

Abstract: A new approach to the monitoring of granulation processes using passive acoustics together with precise control over the granulation process has highlighted the importance of particle–particle and particle–bowl collisions in acoustic emission. The results have shown that repeatable acoustic results could be obtained but only when a spray nozzle water addition system was used. Acoustic emissions were recorded from a transducer attached to the bowl and an airborne transducer. It was found that the airborne transducer detected very little from the granulation and only experienced small changes throughout the process. The results from the bowl transducer showed that during granulation the frequency content of the acoustic emission shifted towards the lower frequencies. Results from the discrete element model indicate that when larger particles are used the number of collisions the particles experience reduces. This is a result of the volume conservation methodology used in this study, therefore larger particles results in less particles. These simulation results coupled with previous theoretical work on the frequency content of an impacting sphere explain why the frequency content of the acoustic emissions reduces during granule growth. The acoustic system used was also clearly able to identify when large over-wetted granules were present in the system, highlighting its benefit for detecting undesirable operational conditions. High-speed photography was used to study if visual changes in the granule properties could be linked with the changing acoustic emissions. The high speed photography was only possible towards the latter stages of the granulation process and it was found that larger granules produced a higher magnitude of acoustic emission across a broader frequency range. [Copyright &y& Elsevier]

Highlights: [•] A new time resolved PA spectroscopy of Br2 molecules using a nanosecond pulses. [•] To understand the coupling mechanism of optical energy into the acoustic energy. [•] Clustering of acoustic frequencies in Br2 molecules for the first time. [•] Decay behavior of Br2 molecules with respect to time. [Copyright &y& Elsevier]

Abstract: A consortium composed of Thelma Biotel and Center of Oceanography developed and tested an acoustic 3-axis accelerometer transmitter. The first testing phase took place in experimental tanks and consisted of externally attaching prototype data logging tags in Lusitanian toadfish (Halobatrachus didactylus Bloch & Schneider, 1801) and comparing raw logged data with observed behaviours to obtain characteristic accelerometer data patterns that could be assigned to those typical movements. Four behavioural “signatures” were considered, two different burrowing movements, attack towards a prey and general activity. The second phase was the development of a prototype with integrated software capable of identifying those accelerometer typical patterns, process the information and transmit relevant data acoustically. Burrowing movements and activity were detected and transmitted with 100% accuracy while attacks were detected with a 61% successful rate. The third phase took place in the Mira estuary (SW Portugal) with 2 groups (five and six individuals each) of free living toadfish to test the codified acoustic signal transfer from the AccelTag to the acoustic receiver array. The novelty of the AccelTag is that is has the measuring capabilities of an accelerometer archival tag but without the necessity of recapture the tagged fish, since it has the ability of analysing the logged data, extract very detailed species dependent information and transmit the relevant processed data. [Copyright &y& Elsevier]

Highlights: [•] We analyzed the correlation between the biomass indices of sardine and anchovy derived from hydro/acoustic surveys and the MEDITS survey carried out in the Strait of Sicily. [•] The two surveys data on sardine and anchovy were highly correlated. [•] We estimated the catchability coefficients for sardine and anchovy of the MEDITS survey. [•] MEDITS survey sampled only a very reduced part of the available biomass of small pelagics (1.1–1.6%) along the trawling line. [•] MEDITS data can be used to investigate the population dynamics of the stocks of sardine and anchovy in the Mediterranean. [ABSTRACT FROM AUTHOR]

Abstract: Numerical simulation of chemical reactions inside an isolated spherical bubble of oxygen has been performed for various ambient bubble radii at different frequencies and acoustic amplitudes to study the effects of these two parameters on the range of ambient radius for an active bubble in sonochemical reactions. The employed model combines the dynamic of bubble collapse with the chemical kinetics of single cavitation bubble. Results from this model were compared with some experimental results presented in the literature and good apparent trends between them were observed. The numerical calculations of this study showed that there always exists an optimal ambient bubble radius at which the production of oxidizing species at the end of the bubble collapse attained their upper limit. It was shown that the range of ambient radius for an active bubble increased with increasing acoustic amplitude and decreased with increasing ultrasound frequency. The optimal ambient radius decreased with increasing frequency. Analysis of curves showing optimal ambient radius versus acoustic amplitude for different ultrasonic frequencies indicated that for 200 and 300kHz, the optimal ambient radius increased linearly with increasing acoustic amplitude up to 3atm. However, slight minima of optimal radius were observed for the curves obtained at 500 and 1000kHz. [Copyright &y& Elsevier]

Abstract: This study presents the data elements to develop a new processing route to transform elastomeric waste residue (particulates) into acoustic and thermal insulation materials that can compete with commercial products. The approach is to bind these grain and fibre particulates with a foaming polyurethane or a similar polymer, the chemistry of which can be manipulated to control the structure stiffness and the evolution of the foaming gas into open or closed cells. Here the study uses two examples of such residues, tyre and carpet shreds both composed of fibres trapping grains of either rubber or PVC. Compounds were made from these systems with different PU binders and the structural properties (density, porosity, air flow resistivity, tortuosity and stiffness) and performance properties (sound absorption, sound transmission, impact sound insulation and thermal conductivity) were measured as a function of binder loading and chemistry. The data obtained show clearly that performance can be tailored by tailoring structural properties resulting with materials that match or even outperform commercial products. The data set obtained here can be usefully exploited with available acoustic and thermal insulation materials model to take the approach further and extended to other waste systems. [Copyright &y& Elsevier]

Abstract: Temperature conditions in a coal charge during coking depend on the location towards heating walls of a coke oven. Heating rate as well as residence time in a final temperature distinctly increases from a central axis to heating walls of coking chamber. Differentiated temperature conditions affect physical structure of a coal heated. This influence has been studied using molecular acoustics and densitometric methods, EPR spectroscopy and optical microscopy. Distinct correlations between the position of the coal charge in coking chamber and physical properties of resultant coke have been found. Three zones with the coke of various physical structures have been distinguished in relation to their position toward heating walls of coking chamber: zone I — close to the heating wall, zone II — the middle area and zone III — close to the central axis. Coke produced close to the heating walls of the coke oven has better ordered texture of carbon matrix but more free radicals and worse elasticity than the coke from the middle area. Coke obtained in the central part of coking chamber has the lowest degree of textural order, the lowest porosity but, in a consequence, the best elasticity. The best quality seems to have the coke from the middle area. [Copyright &y& Elsevier]

Abstract: Scanning Brillouin microscopy visualizes the temporal evolution of a heterogeneous hypersonic profile during chemical reactions and transport processes around a planar phase boundary between an epoxy resin and hardener. The hypersonic investigations are interpreted in terms of structural formation and annihilation in the layered sample and are compared to results obtained for a well mixed bulk sample of the same composition of reactants. Chaotic transport channels are made responsible for the creation of local glassy heterogeneities not observable in the bulk material on a macroscopic level. [Copyright &y& Elsevier]

Abstract: The rate of loss of the energy of non-equilibrium electrons due to inelastic interaction with intravalley acoustic phonons in a degenerate surface layer is calculated for low temperatures when the approximations of the well-known traditional theory are not valid. The loss characteristics for GaAs and Si seem to be significantly different compared to what follows from the traditional approximations. [Copyright &y& Elsevier]

Abstract: The acoustic method of Pasynski was applied to investigate solvation of short-chained normal alcohols in n-heptane and n-propanol as solvents. For both solvents, the dependence of solvation numbers on length of the solute molecules is surprisingly similar, except that for the shortest alcohols. Applicability of the acoustic method for investigation of intermolecular interactions in non-aqueous liquid systems was proved. Hypothesis on some structural similarity of associated alcohol and hydrocarbon in liquid state is formulated. [Copyright &y& Elsevier]

Abstract: The paper reports the methods of preparing molecular magnets and patterning of the molecules on a semiconductor surface. A highly magnetically aligned metallothionein containing Mn and Cd (Mn,Cd-MT-2) is first synthesized, and the molecules are then placed into nanopores prepared on silicon (001) surfaces using electron beam lithography and reactive ion-etching techniques. We have observed the self-assemble growth of the MT molecules on the patterned Si surface such that the MT molecules have grown into rod or ring type three-dimensional nanostructures, depending on the patterned nanostructures on the surface. We also provide scanning electron microscopy, atomic force microscopy, and magnetic force microscope studies of the molecular nanostructures. This engineered molecule shows molecular magnetization and is biocompatible with conventional semiconductors. These features make Mn,Cd-MT-2 a good candidate for biological applications and sensing sources of new nanodevices. Using molecular self-assembly and topographical patterning of the semiconductor substrate, we can close the gap between bio-molecules and nanoelectronics built into the semiconductor chip. [Copyright &y& Elsevier]

Abstract: This study presents acoustic and electro-magnetic articulography (EMA) data for the back rounded vowel /u/ in preboundary position in French. Five boundary types are examined: the Utterance, the Intonational phrase, the Accentual phrase, the Word and the Syllable. The three speakers studied produce similar acoustic output, with both F1 and F2 becoming lower before stronger prosodic boundaries. However, the Utterance boundary has a particularly strong effect on F1, which is particularly low before this boundary. To achieve the acoustic output observed, the speakers adopt different articulatory strategies at different prosodic boundaries. The strategies observed before the strongest boundaries are tongue dorsum backing (coupled with either raising or lowering, depending on the speaker); tongue tip retraction; and lip protrusion. Somewhat unexpectedly in light of acoustic considerations, lip constriction is observed to be greater before the weaker prosodic boundaries. This result, considered in conjunction with the tongue data and with the lip protrusion data, leads us to suggest that the French speakers in our study are actively aiming to prevent F2 from becoming too high before the weaker prosodic boundaries. We suggest that a high F2 for /u/ may lead to perceptual confusion with the front rounded vowel /y/, which is also present in the French phoneme inventory. This result echoes our previous results for the front unrounded vowel /i/ (Tabain & Perrier, 2005. Articulation and acoustics of /i/ in preboundary position in French. Journal of Phonetics, 33, 77–100), and suggests that the structure of a language''s phoneme inventory has important effects on the articulatory strategies adopted by its speakers. [Copyright &y& Elsevier]

Abstract: Deposition of Sb2Te3 thin films on polycrystalline Au substrates by electrochemical atomic layer epitaxy (ECALE) is described in this paper. Electrochemical aspects were characterized by means of cyclic voltammetry, anodic potentiodynamic scanning and coulometry. A steady ECALE deposition for Sb2Te3 compound could be attained after negatively adjusting the underpotential deposition (UPD) potentials of Sb and Te on Au in steps over the initial 40 cycles, and the potentials could be kept constant for the following deposition. A 400 cycle deposit, which was grown with the steady deposition potentials, was proved to be a single phase Sb2Te3 compound by X-ray diffraction analysis and SEM observation shows the deposit consisted of nanoscale particles with average size about 100nm. The 2:3 stoichiometric ratio of the deposit was further verified by energy dispersive X-ray (EDX) quantitative analysis. [Copyright &y& Elsevier]

Abstract: Study of molecular actions of thyroid hormone receptor β (TRβ) mutants in vivo has been facilitated by creation of a mouse model (TRβPV mouse) that harbors a knockin mutant of TRβ (denoted PV). PV, which was identified in a patient with resistance to thyroid hormone, has lost T3 binding activity and transcription capacity. The striking phenotype of thyroid cancer exhibited by TRβPV/PV mice has allowed the elucidation of novel oncogenic activity of a TRβ mutant (PV) [PAS1] beyond nucleus-initiated transcription. PV was found to physically interact with the regulatory p85α subunit of phosphatidylinositol 3-kinase (PI3K) in both the nuclear and cytoplasmic compartments. This protein–protein interaction activates the PI3K signaling by increasing phosphorylation of AKT, mammalian target of rapamycin (mTOR), and p70S6K. PV, via interaction with p85α, also activates the PI3K-integrin-linked kinase-matrix metalloproteinase-2 signaling pathway in the extra-nuclear compartment. The PV-mediated PI3K activation results in increased cell proliferation, motility, migration, and metastasis. In addition to affecting these membrane-initiated signaling events, PV affects the stability of the pituitary tumor-transforming gene (PTTG) product. PTTG (also known as securin), a critical mitotic checkpoint protein, is physically associated with TRβ or PV in vivo. Concomitant with T3-induced degradation of TRβ, PTTG is degraded by the proteasome machinery, but no such degradation occurs when PTTG is associated with PV. The degradation of PTTG/TRβ is activated by the direct interaction of the T3-bound TRβ with the steroid receptor coactivator-3 (SRC-3) that recruits a proteasome activator (PA28γ). PV that does not bind T3 cannot interact directly with SRC-3/PA28γ to activate proteasome degradation, and the absence of degradation results in an aberrant accumulation of PTTG. The PV-induced failure of timely degradation of PTTG results in mitotic abnormalities. PV, via novel protein–protein interaction and transcription regulation, acts to antagonize the functions of wild-type TRs and contributes to the oncogenic functions of this mutation. [Copyright &y& Elsevier]

Bisphosphoglycerate mutase is an erythrocyte-specific enzyme catalyzing a series of intermolecular phosphoryl group transfer reactions. Its main function is to synthesize 2,3- bisphosphoglycerate, the allosteric effector of hemoglobin. In this paper, we directly observed real-time motion of the enzyme active site and the substrate during phosphoryl transfer. A series of high resolution crystal structures of human bisphosphoglycerate mutase co-crystallized with 2,3-bisphosphoglycerate, representing different time points in the phosphoryl transfer reaction, were solved. These structures not only clarify the argument concerning the substrate binding mode for this enzyme family but also depict the entire process of the key histidine phosphorylation as a "slow movie". It was observed that the enzyme conformation continuously changed during the different states of the reaction. These results provide direct evidence for an "in line" phosphoryl transfer mechanism, and the roles of some key residues in the phosphoryl transfer process are identified. [ABSTRACT FROM AUTHOR]

Abstract: We have measured the noise at ∼1.6MHz in the current produced by a surface acoustic wave (SAW) single-electron pump. The current can be varied by altering the voltage applied to surface gates. Over the range of gate voltage where the current is close to the quantized value corresponding to one electron being transported per cycle of the SAW, the noise in the current is dominated by shot noise, whereas away from this range the noise mostly arises from switching of the charge states of electron traps in the material. By combining measurements of the shot noise and the current we determined how the error rates—the probabilities of transporting zero or two electrons in a cycle—vary with gate voltage when the current is close to the quantized value. [Copyright &y& Elsevier]

Abstract: We have studied the atomic geometries and electronic properties of the tris-(8-hydroxyquinoline) aluminum (Alq3)/Al interface using density functional calculations. The calculated interface dipoles agree reasonably well with the experiments and the origin of the interface dipole formation mainly comes from the alignment of the permanent dipoles of Alq3 molecules. The HOMO levels of the Alq3 molecules significantly depend on the orientation of the molecular permanent dipoles and the interfacial gap state observed by experiments is ascribed to the co-existence of the two orientations of the molecular dipoles. [Copyright &y& Elsevier]

Abstract: Ultrasonic velocities and densities were measured in the mixtures of water with ethylene glycol (EG) and polyethylene glycol (PEG) 200, 400 in the temperature range from 291.15 to 303.15K. Adiabatic compressibilities were calculated from Laplace''s equation based on the experimental results obtained. Variations of these values with concentration and temperature were studied. Structural interactions and the formation of a compact pseudostable structure at very low concentrations of ethylene glycol and polyethylene glycols were observed. The plots of the adiabatic compressibility versus the mole fraction of PEG and EG display two characteristic points at low concentrations: the intersection of the isotherms and their minimum. Such relations between adiabatic compressibility, concentration and temperature are usually attributed to the formation of pseudo-stable molecular structures. To formulate a model of local structures present in the investigated molecular systems, it is indispensable to get an insight into hydration of molecules and the formation of hydrogen bonds. Therefore, the attention was focused particularly on these problems. [Copyright &y& Elsevier]

In this paper we discuss the use of high-frequency acoustic waves (approximately 0.8–1 MHz, megasonic) as a means of enhancing cleaning efficiency for postetch polymer removal in the Cu/low-k dual damascene process. Attempts were made to integrate 0.13-μm technology Cu/low-k dual damascene structures without hard mask, by using acoustic agitation as a means of improving process margin over fencing issues associated with this integration scheme. We have demonstrated that it is possible to use this method on 0.13-μm technology Cu/low-k dual damascene structures without damage. Contact resistance yields of more than 90% were still achievable, although the processing time was reduced significantly with the use of megasonic enhancement. [Copyright &y& Elsevier]

The velocity of ultrasound (c) and the density (ρ) have been measured in mixtures of water and polyethylene glycols in the temperature range from 288 to 328 K. Based on the data obtained, the adiabatic compressibility coefficients (βad) have been calculated from Laplace''s equation. The variations of c, ρ and βad with concentration (μ, mole fraction) and temperature have been studied. Structural interactions and the formation of a compact pseudo-stable structure in the region of very low polyethylene glycol concentrations have been reported. The structure built from these mixtures can be neither of the liquid clathrate-like hydrate type I nor type II. [Copyright &y& Elsevier]

New cyclopentadienyl derivatives of rhodium COD complexes [Cp*=C5H4COOCH2CH&z.dbnd6;CH2 (1); C5H4CH2CH2CH&z.dbnd6;CH2 (2); C5H(i-C3H7)4 (3)] and carbonyl complex [Cp*=C5H(i-C3H7)4 (4)] were synthesized from [RhCl(COD)]2 and [RhCl(CO)2]2. 1, 2 and 3 oxidized by iodine gave iodine bridged dimers 5, 6 and 7, respectively. Triphenyl phosphine, carbon monoxide and carbon disulfide molecules broke down the iodine bridged structure easily and produced monomer products Cp*RhI2L [Cp*=C5H4COOCH2CH&z.dbnd6;CH2, L=CS2 (8); L=PPh3 (9). Cp*=C5H(i-C3H7)4, L=CO (10)]. All of these new compounds were characterized by elemental analysis, 1H NMR, IR, UV–Vis and mass spectroscopy. The crystal structure of 1 was solved in the triclinic space group P1¯ with one molecule in the unit cell, the dimensions of which are a=7.082(9) A˚, b=8.392(3) A˚, c=13.889(5) A˚, α=101.19(3)°, β=99.06(6)°, γ=105.11(5)°, and V=763(1) A˚3. The crystal structure of 3 was solved in the orthorhombic space group Pn21a with four molecules in the unit cell, the dimensions of which are a=9.748(3) A˚, b=16.054(5) A˚, c=14.816(4)A˚ and V=2319(1) A˚3. Least squares refinement leads to values for the conventional R1 of 0.0251 for 1 and 0.0558 for 3, respectively. Compared to that in 1, a shorter metal–ligand bond length in 3 was observed and this is attributed to the rich electron density on Rh(I) metal center piled up by the C5H(i-C3H7)4 ligand. [Copyright &y& Elsevier]

In this work, we describe a novel pulse mode shear horizontal-surface acoustic wave (SH-SAW) polymer coated biosensor that monitors rapid changes in both amplitude and phase. The SH-SAW sensors were fabricated on 36° rotated Y-cut X propagating lithium tantalate (36 YX.LT). The sensitivity of the device to both mass loading and visco-elastic effects may be increased by using a thin guiding layer of cross-linked polymer. Two acoustic modes are excited by the electrodes in this crystalline direction. Metallisation of the propagation path of the 36 YX.LT devices allows the two modes to be discriminated. Successive polymer coatings resulted in the observation of resonant conditions in both modes as the layer thickness was increased. Using the 36 YX.LT devices, we have investigated the application of a novel pulse mode system by sensing a sequence of deposition and removal of a biological layer consisting of vesicles of the phospholipid POPC. A continuous wave system was used to verify the accuracy of the pulse mode system by sensing a series of poly(ethylene glycol) (PEG) solutions. The data clearly demonstrates the ability of the 36 YX.LT pulse mode system to provide rapid measurements of both amplitude and phase for biosensing applications. [Copyright &y& Elsevier]

In this paper, a brief overview of our works on macromolecular network and molecular structure of coal via the elastic properties studies has been made. The recent investigations of raw, demineralized and solvent-treated coals, as well as coal extracts by means of molecular acoustics methods, have been described. [Copyright &y& Elsevier]

We report rates of oxygen exchange with bulk solution for an aqueous complex, IVGeO4Al12(OH)24(OH2)128+(aq) (GeAl12), that is similar in structure to both the IVAlO4Al12(OH)24(OH2)127+(aq) (Al13) and IVGaO4Al12(OH)24(OH2)127+(aq) (GaAl12) molecules studied previously. All of these molecules have &epsiv;-Keggin-like structures, but in the GeAl12 molecule, occupancy of the central tetrahedral metal site by Ge(IV) results in a molecular charge of +8, rather than +7, as in the Al13 and GaAl12. Rates of exchange between oxygen sites in this molecule and bulk solution were measured over a temperature range of 274.5 to 289.5 K and 2.95 < pH < 4.58 using 17O-NMR.Apparent rate parameters for exchange of the bound water molecules (η-OH2) are kex298 = 200 (±100) s−1, ΔH‡ = 46 (±8) kJ · mol−1, and ΔS‡ = −46 (±24) J · mol−1 K−1 and are similar to those we measured previously for the GaAl12 and Al13 complexes. In contrast to the Al13 and GaAl12 molecules, we observe a small but significant pH dependence on rates of solvolysis that is not yet fully constrained and that indicates a contribution from the partly deprotonated GeAl12 species.The two topologically distinct μ2-OH sites in the GeAl12 molecule exchange at greatly differing rates. The more labile set of μ2-OH sites in the GeAl12 molecule exchange at a rate that is faster than can be measured by the 17O-NMR isotopic-equilibration technique. The second set of μ2-OH sites have rate parameters of kex298 = 6.6 (±0.2) · 10−4 s−1, ΔH‡ = 82 (±2) kJ · mol−1, and ΔS‡ = −29 (±7) J · mol−1 · K−1, corresponding to exchanges &ap;40 and &ap;1550 times, respectively, more rapid than the less labile μ2-OH sites in the Al13 and GaAl12 molecules. We find evidence of nearly first-order pH dependence on the rate of exchange of this μ2-OH site with bulk solution for the GeAl12 molecule, which contrasts with Al13 and GaAl12 molecules. [Copyright &y& Elsevier]

Abstract: We use Brillouin spectra collected in the visible, ultraviolet and X-ray frequency regions to derive the imaginary part of acoustic compliance, J″(ω), over an extended frequency range from fractions of GHz to tens of THz. We find that J″(ω) accurately reproduces the shape of the self-particle susceptibility as determined by incoherent neutron scattering. This analysis is here applied to the case of liquid water in comparison with glycerol, another representative associated liquid, for which the observed correspondence has been proven to imply a close connection between dissipation through acoustic channels and generalized density of states. [Copyright &y& Elsevier]

Abstract: In this letter, we study the electron–ion quantum plasma oscillations in molecule using the linearized quantum hydrodynamic model in conjunction with the Poisson''s equation. We obtain a new low-frequency electrostatic excitation in the molecule, i.e., quantum ion-acoustic wave oscillations in addition to the high-frequency dispersion. [Copyright &y& Elsevier]

Abstract: Ultrasonic studies of the group of halogens of benzene and particularly dependence of acoustic parameters on the structure of organic liquids, demonstrate some interesting regularities in the group of these compounds in gas and liquid states. In this paper results for five cyclic liquids: bromo-, chloro-, fluoro- and jodobenzene are discussed and compared to benzene. Vibrational relaxation was observed in all the compounds. The studies reported here as well as other experimental for great number of compounds support the conclusion that almost all vibrational relaxation processes in liquids can be described using a single relaxation time. It also seems that all vibrational degrees of freedom of the molecule take part in this vibrational process. It seems that differences in transition probabilities between molecules studied could be caused by additional attraction between of molecules having a significant dipole moments. [Copyright &y& Elsevier]