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Understanding the nature of the active species of the TiCl4/MgCl2 Ziegler–Natta catalyst is special important and challenge. In this work, the pre-treated TiCl4/MgCl2 pre-catalyst by heptane washing (H-Cat) and AlR3 activation (Al-Cat) were prepared and analyzed and then used to conduct butadiene (Bd)-isoprene (Ip) copolymerizations. It was proved that the adsorbed Al compounds on the Al-Cat surfaces after suffering heptane washing increased with the increase in the concentration of alkylaluminium in the pre-catalyst activation process, indicating the stable absorption of Al compounds on the active species and then influencing the catalytic behavior of the active species. Correlated the titanium oxidation state and the catalytic activity, Ti3+ species were more likely the active species for Bd-Ip copolymerization. Ti3+with adsorption of AlR2Cl on Mg adjacent to the Ti species showed reduced activity and produced polymers with high trans-1,4-configuration and relatively high molecular weight (Mw). This study is anxious to provide further understanding on the mechanism of conjugated diene polymerization catalyzed by heterogeneous Ziegler–Natta catalysts. The increase in alkylaluminium concentration during the pre-catalyst activation process changed the chemical surroundings and oxidant state of Ti and then resulted in an obvious increase in adsorbed Al and Ti2+ amount on the catalyst surface, which influenced the activity and stereoregularity for diene polymerization.

Phenalenyls (PLYs) are important synthons in many functional and electronic materials, which often display favorable molecule-to-molecule overlap for electron or hole transport. They also serve as a prototype for π-stacking pancake bonding based on two-electron multicenter bonding (2e/mc). Unexpected near-doubling of the binding energy is obtained for the positively charged PLY2+ dimer with an effect similar to that seen for the positively charged olympicenyl (OPY) radical dimer. This charge effect is reversed for the perfluorinated (PF) dimers, and the negatively charged perfluorinated (PF) dimers PF-PLY2- and PF-OPY2- become strongly bound. Long-range interactions reflect these differences. Also surprising is that in this case the pancake bonding corresponds to single-electron (1e/mc) or a three-electron (3e/mc) multicenter bonding in contrast to the 2e/mc bonding that occurs for the neutral radical dimers. The strong preference for a large intermolecular overlap is maintained in these charged dimers. Importantly, the preference for π-bonding in the charged dimers compared to σ-bonding is strongly enhanced relative to the neutral PLY dimers.

Herein, we disclose an efficient cobalt-catalyzed three-component coupling of benzamides, diazo compounds, and tert-butyl hydroperoxide, which provides an efficient approach to construct C(sp2)-C(sp3) and C-O bonds in one-pot accompanied with C-H activation. This protocol features low catalyst loading (4 mol %), the avoidance of additives, and excellent functional group compatibility, providing three-component coupling adducts with high yields under mild conditions (up to 88%). Mechanism studies show that the reaction may involve a radical process.

We report herein evidence of EE triple bonds (E = Group 13) promoted by the perpendicularly surrounding M4 (M = Li and Na) motifs. The global minimum of E2M4 (E = B, Al, and Ga) is a D4h-symmetry structure where E–E is surrounded perpendicularly by square M4 motifs, whereas the Cs-symmetry structure formed by E–E–M surrounded partially by M3 motifs is the lowest-energy structure for E = In and Tl. Chemical bonding reveals that strong charge transfer from M4 to E2 dimer not only provides efficient electrons to form EE triple bonds, but also the resulting electrostatic interactions between M4 and E2 play a driving force to stabilize these intriguing triply bonded species.

The electronic and structural prerequisites for a multi-layered molecular rotor have been demonstrated herein in terms of nine 18-valence-electron metallocene sandwich complexes. First, the lack of strong covalent bonds between layers is a key issue to obtain a barrier-free rotation of one layer relative to other layers, where the considerable energetic but unidirectional (such as electrostatic interactions) interactions are needed between layers to keep the structural integrity against fragment separation and structural distortion in a rotation process. Second, one or more layers should possess continuous and delocalized π electron clouds to provide a driving force for the barrier-free rotation. More importantly, besides a negligible rotation barrier, the reasonable rotational period associated with the ultra-soft rotation mode is a critical point for the observability of dynamical behavior in multi-layered molecular rotors.

Management of glioblastoma multiforme (GBM), a cerebral glioma with highest-grade malignancy, is a crucial challenge to current anticancer treatment because the lack of GBM-targeting capability of antitumor drug, such as carmustine (BCNU) with a short half-life, along with low blood-brain barrier (BBB) permeability to achieve the clinical efficacy. Hence, polyethyleneimine-poly(lactic-co-glycolic acid) nanoparticles comprising stable core-shell structure with tamoxifen were crosslinked with sialic acid (SA-TAM-PEI-PLGA NPs) as nanocarriers to improve bioavailability of BCNU for pharmacotherapy. The brain-targeted experiments revealed that an increasing SA level improved BBB permeability for BCNU, and was associated with a reduction in transendothelial electrical resistance and an increase in propidium iodide penetration of endothelial monolayer. Immunocytochemical staining images evidenced that surface SA was critical in triggering transcytosis through N-acetylglucosamine on human cerebral microvessel endothelia, and surface crosslinking restrained macrophage phagocytosis. A high TAM level on the carrier surface reduced the survival rate of human U87, and western blots showed that conjugated TAM induced apoptosis of the cancer cells. The use of SA-TAM-PEI-PLGA NPs carrying BCNU as a pharmaceutical preparation is an effective strategy to overcome the BBB restriction and activate apoptosis of tumor cells to prevent the proliferation of GBM.

The earth-abundant cobalt-catalyzed anti-Markovnikov hydroalkylation of unactivated alkenes with oxime esters was achieved by introducing an 8-aminoquinoline directing group on the alkenes. The catalytic system, consisting of commercially available Co(acac)3 and PhMeSiH2, enables the construction of unfunctionalized C(sp3)-C(sp3) bonds and features exclusive anti-Markovnikov selectivity, good functional group tolerance, and the avoidance of an extra ligand, oxidant, or base. Mechanistic insight into this new catalytic system indicates the involvement of both alkyl radical and cobalt hydride intermediates.

In this work, we systematically explored clusters with formula B7M2− and B8M2 (M = Zn, Cd, Hg). The putative global minima are formed by an M2 dimer and a disk-shaped boron wheel. Moreover, the chemical bonding analysis revealed that charge transfer from the metal atoms to the boron motifs resulted in (B7)3−(M2)2+ and (B8)2−(M2)2+ complexes with double (σ + π) aromatic boron wheels and a single bond for the metallic dimer. Above all, the computed rotational barriers of the M–M fragment with respect to the boron disk and molecular dynamics simulations indicate a virtually barrierless spin, resembling a magnetic stirrer on a baseplate.

Chemical fractionation of the n-BuOH partition, which was generated from the EtOH extract of the flower buds of Tussilago farfara, afforded a series of polar constituents including four new sesquiterpenoids ( 1 – 4 ), one new sesquiterpenoid glucoside ( 5 ) and one known analogue ( 6 ) of the eudesmane type, as well as five known quinic acid derivatives ( 7 – 11 ). Structures of the new compounds were unambiguously characterized by detailed spectroscopic analyses, with their absolute configurations being established by X-ray crystallography, electronic circular dichroism (ECD) calculation and induced ECD experiments. The inhibitory effect of all the isolates against LPS-induced NO production in murine RAW264.7 macrophages was evaluated, with isochlorogenic acid A ( 7 ) showing significant inhibitory activity.

The present work developed a virtual reality (VR) counterconditioning procedure (VRCP), and investigated its efficacy in treatment of cue-induced craving in individuals with methamphetamine (METH) dependence. In study 1, thirty-one patients diagnosed with METH dependence received VRCP, while twenty-nine METH-dependent patients in waiting-list group did not. In study 2, the VRCP was computerized as a VR treatment system. Six-hundred and twelve abstinent individuals with a history of METH dependence received the computerized VRCP, while two-hundred seventy-six abstinent individuals with a history of METH dependence in waiting-list group did not. Patients with METH dependence who received VRCP showed a significantly larger decrease on the score of METH-craving and METH-liking from baseline to follow-up assessments, compared to those who did not received VRCP. Participants received VRCP showed a significantly larger decrease in HRV indexes on time domain and non-linear domain from baseline to follow-up assessments during exposure to VR cues, compared to those in waiting-list group. These findings indicate that the counterconditioning procedure under VR environment may be a useful strategy in suppressing cue-induced reactivity for patients with METH dependence.

A novel amphiphilic supramolecular polymer (ASP) with rigid linear main chain has been constructed by the co-assembly of a rigid amphiphilic monomer and cucurbit[8]uril (CB[8]) in water, driven by CB[8]-based host-guest interactions. The ASP could further self-assemble into well-defined architectures including nanotubes and 2D films, depending on its concentration. Moreover, pH-responsive behavior of the ASP was also observed.

The exhaustive exploration of the potential energy surfaces of CE2M2 (E = Si-Pb, M = Li, and Na) revealed seven global minima containing a planar tetracoordinate carbon (ptC). The design was based on a π-localization strategy, resulting in a ptC embedded in a linear or a bent allene-type E=C=E motif. The magnetic response showed a σ-aromaticity in the bent E=C=E fragments. The bonding analysis indicated that the ptCs form C-E covalent bonds and C-M electrostatic interactions.

A Carbon-nanotube (CNT)/Polyvinyl alcohol (PVA) composite film-coated thin core fiber (TCF) optics sensor is proposed for monitoring relative humidity (RH). The unique Michelson type fiber interferometer sensor consists a short segment of TCF, the tip of which is melted into a convex shape and coated with a hydroscopic CNT/PVA film. The proposed sensor is linearly responsive to relative humidity (RH) beyond the humidity range 70%RH, with maximum sensitivity of −0.4573 dB/%RH. The advantages of this sensor are its compact size, excellent stability and facile fabrication process.

The multistep thermal decomposition behavior and kinetic feature of magnesium nitrate hydrate (MNH) were studied systematically in this study. Firstly, the multistep reaction processes in MNH pyrolysis were identified by Thermogravimetry-Fourier Transform Infrared analysis. Then, a common method of data processing, mathematical peak deconvolution, was used to separate such complex multistep reaction processes. Additionally, kinetic triplets of each separated process were determined by Friedman isoconversional method and Ozawa kinetic equation. Finally, kinetic features of each separated process were interpreted in terms of the physico-geometrical reaction mechanism. The results showed that MNH pyrolysis was a complex multistep reaction, including three reaction processes. The first two reaction processes were characterized by evolution of H2O, whereas the third reaction process was characterized by evolution of NO2. Three processes obeyed diffusion, order-based and nucleation and growth mechanisms, with E(apparent activation energy) = 80 ± 1, 137 ± 2, 227 ± 4 kJ/mol and A(pre-exponential factor)=(2.5 ± 0.2)×109, (1.5 ± 0.1)×1011 and (8.8 ± 0.2)×1015 s−1, respectively.

The triblock energetic copolymer PLA-b-GAP-b-PS was synthesized successfully through atom-transfer radical polymerization (ATRP) of styrene and ring-opening polymerization of d,l-lactide. The energetic macroinitiator GAP-Br, which was made from reacting equimolar glycidyl azide polymer (GAP) with α-bromoisobutyryl bromide, firstly triggered the ATRP of styrene with its bromide group, and then the hydroxyl group on the GAP end of the resulting diblock copolymer participated in the polymerization of lactide in the presence of stannous octoate. The triblock copolymer PLA-b-GAP-b-PS had a narrow distribution of molecular weight. In the copolymer, the PS block was solvophilic in toluene and improved the stability of the structure, the PLA block was solvophobic in toluene and served as the sacrificial component to prepare porous materials, and GAP was the basic and energetic material. The three blocks of the copolymer were fundamentally thermodynamically immiscible, which lead to the self-assembly of the block copolymer in solution. Further studies showed that the concentration and solubility of the copolymer and the polarity of the solvent affected the morphology and size of the micelles generated from the self-assembly of the PLA-b-GAP-b-PS block copolymer. The micelles generated in organic solvents at 10 mg/mL copolymer concentration were spherical but became irregular when water was used as a co-solvent. The spherical micelles self-assembled in toluene had three distinct layers, and the diameter of the micelles increased from 60 to 250 nm as the concentration of the triblock energetic copolymer increased from 5 to 15 mg/L.

A new set of values for the molar heat capacities of N-(2-aminoethyl)piperazine (AEP) and N,N,N′-trimethylethylenediamine (tMEDA) and their aqueous mixtures over the whole range of compositions are reported in the present work. Molar heat capacities of ternary mixtures of each polyamine with piperazine (PZ): (AEP + PZ + H2O) and (tMEDA + PZ + H2O) were also measured. Measurements were done over the temperature range T = (303.2–353.2) K and p = 101.3 kPa by the differential scanning calorimetry technique. Excess molar heat capacities of aqueous binary mixtures were correlated with composition and temperature using a Redlich–Kister relation, which was then used to correlate molar heat capacities of the mixtures at different temperatures and compositions. The equation fit the results with the average absolute deviation (AAD) of 2.1% and 0.2% for the excess molar heat capacity and molar heat capacity, respectively. A modified Sohnel and Novotný equation was applied to represent the composition and temperature dependence of the molar heat capacity of aqueous ternary mixtures at AAD between the correlated and the experimental data of about 0.1%. The correlations proposed here are of acceptable accuracy for application in process design and engineering.

In recent years, a new class of solvent called ionic liquids had successfully demonstrated potential applications in industrial chemistry and chemical technology due to its desirable properties. To this end, understanding their physico-chemical properties is of high importance. The current study presents a model for predicting the refractive index of binary ionic liquid system containing alcohol (methanol or ethanol or 1-propanol) using the artificial neural network (ANN) algorithm. The refractive index data were correlated as function of temperature, mole fraction, number of carbon atoms in the cation, number of atoms in the anion, number of hydrogen atoms in the anion and number of carbon atoms in the alcohol. Refractive index data from ThermoIL Database were used. Using ANN, a total of 752 data points were used in the calculation and to obtain the optimum neural network parameters. The 6-6-9-1 neural network architecture was found to be the best network using two hidden layers as shown by mean absolute error of 0.00783 and an overall average percentage error of 0.55%. The obtained correlation satisfactorily represents the experimental refractive index data and can be reliably used to predict the refractive index of other binary systems containing the considered cation and anions and the studied alcohols.

In this present work, density of ternary system containing n-tris(hydroxymethyl)methyl-3-aminopropanesulfonic acid (TAPS), glycol, and water was presented. The considered glycols are diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (T4EG). The measurements were done over a temperature range of 298.15 to 343.15 K at normal atmospheric pressure. Different concentrations (4 to 16 % by weight TAPS or 56 to 44 % water, in a fixed amount of glycol – 40 %) were used. The effects of temperature and compositions on the measured properties were discussed and then correlated based on the equation proposed for aqueous salt-glycol systems. Calculation results show that the applied model was satisfactory in representing the measured property of the considered ternary aqueous solutions containing TAPS and glycol.

A novel aluminum/boron/iron-oxide nanothermite with a porous structure was synthesized by sol–gel chemistry combined with an ultrasonic method, in which the aluminum and boron were encapsulated in the nanoferric oxide’s skeleton with an average particle size of 50 nm. The catalytic activity of aluminum/boron/iron-oxide nanothermites for ammonium perchlorate decomposition was studied by thermogravimetry/differential scanning calorimetry. Compared with the thermal decomposition of pure ammonium perchlorate, 7 wt % aluminum/boron/iron-oxide nanothermites decreased the decomposition temperature of ammonium perchlorate by 69°C and increased its apparent decomposition heat by 382.3 J/g. The higher catalyst addition favors further decomposition of ammonium perchlorate. Through the investigation of nano-iron oxide, nanoaluminum, and micrometer-boron for thermal decomposition of ammonium perchlorate, the nano-iron-oxide particles play the leading role in aluminum/boron/iron-oxide nanothermites for thermal decompo...

The molar heat capacity, Cp, of aqueous 1,3-diaminopropane (DAP), 1,4-diaminobutane (DAB) and their corresponding blends with piperazine (PZ) were measured at temperatures from 303.2 K to 353.2 K by differential scanning calorimetry. The correlation of Cp of the aqueous binary mixtures with temperature and concentration was successfully described by a Redlich–Kister type equation using excess molar heat capacity data. A modified Sohnel and Novotny equation was used to represent the temperature and concentration dependence of Cp of the ternary mixtures. The average absolute deviations between the experimental and the predicted Cp data were 0.2% and 0.1% for the binary and ternary mixtures, respectively. The results suggest that the experimental data presented in this work were represented well by the proposed correlations.

Aqueous amino acid salt solutions are promising alternatives to aqueous alkanolamine absorbents for CO2 capture. In this study, the absorption of CO2 in two amino acid salt systems: aqueous potassium l -asparaginate (KAsn) and aqueous potassium l -glutaminate (KGln) were investigated. Using a vapor–liquid equilibrium apparatus, the solubility of CO2 in aqueous KAsn and KGln solutions were determined at temperatures 313.2, 333.2, and 353.2 K and pressures up to 950 kPa. The amino acid salt concentration in the solutions was varied from 8.5 to 34.0 wt% for KAsn and 9.2 to 36.8 wt% for KGln. The studied amino acid salt systems were found to have appreciable CO2 absorption capacities, which were comparable with those of commonly used alkanolamines. A modified Kent–Eisenberg model was applied to correlate CO2 solubility (expressed as mole CO2 per mole amine) in the solution with CO2 partial pressure, temperature, and amino acid salt concentration. The model satisfactorily predicted the equilibrium data. The obtained average absolute deviations between the experimental and the calculated values of equilibrium CO2 partial pressures were 12.8% and 10.3%, for aqueous KAsn and KGln systems, respectively.

In this present work, new experimental data for density and vapour pressure of the mixed-solvent desiccant systems containing {40 wt% glycol (propylene or dipropylene or tripropylene) + (4 or 9 or 16 wt%) magnesium chloride salt + water} were reported for temperatures up to 343.15 K at normal atmospheric condition. The density and vapour pressure data obtained are presented as a function of temperature and composition. An empirical equation was used to correlate the temperature and compositional dependence of the density values. A model based on the mean spherical approximation for aqueous electrolyte solutions incorporating the pseudo-solvent approach was used to represent the vapour pressure as a function of temperature and composition. Satisfactory results were obtained for both density and vapour pressure calculations.

Thermophysical property characterization of aqueous potassium and sodium salt solutions containing serine was conducted in this study; specifically the system’s density, refractive index, electrical conductivity, and viscosity. Measurements were obtained over a temperature range of (298.15 to 343.15) K and at normal atmospheric pressure. Composition range from x1 = 0.009 to 0.07 for aqueous potassium and sodium salt solutions containing serine was used. The sensitivity of the system’s thermophysical properties on temperature and composition variation were discussed and correlated based on the equations proposed for room temperature ionic liquids. The density, viscosity, and refractive index measurements of the aqueous systems were found to decrease as the temperature increases at fixed concentration and the values increase as the salt concentration increases (water composition decreases) at fixed temperature. Whereas, a different trend was observed for the electrical conductivity data; at fixed concentration, the conductivity values increase as the temperature increases and at fixed temperature, its value generally increases as the salt concentration increases but only to a certain level (specific concentration) wherein the conductivity of the solution starts to decrease when the concentration of the salt is further increased. Calculation results show that the applied models were satisfactory in representing the measured properties in the aqueous amino acid salt solution containing serine.

In this work, we report new experimental data on the molar heat capacities of two chemically stable diamines, which are potential absorbents for CO 2 capture. They are N , N , N ′, N ′-tetramethylethylenediamine (TMEDA) and N , N , N ′, N ′-tetramethyl-1,3-propanediamine (TMPDA). The molar heat capacities of their corresponding aqueous binary and ternary (with piperazine) mixtures were also measured. Measurements were performed at temperatures from 303.15 to 353.15 K by heat flow differential scanning calorimetry. The excess molar heat capacities of the binary mixtures were determined and a Redlich–Kister-type equation was applied to correlate the data with temperature and composition. The molar heat capacities of the ternary mixtures were represented as a function of temperature and amine concentration using a modified form of the Sohnel and Novotny equation. The applied correlations satisfactorily represented the heat capacity data as suggested by the low values of the average absolute deviation of 0.2%, 0.4%, and 0.1% for the pure, binary, and ternary systems, respectively.

In this work, new experimental data on the solubility of carbon dioxide in aqueous binary solutions of reline and its ternary solutions with monoethanolamine (MEA) are reported. Measurements were performed at temperatures (313.2, 333.2, 353.2) K and pressures up to around 900 kPa using a (vapour + liquid) (vapour-recirculation) equilibrium apparatus. It was found that blending reline with MEA greatly improved the CO2 absorption capacity of aqueous reline solutions. The obtained solubility data (in terms of CO2 loading) were correlated with CO2 partial pressure, temperature, and solute (reline + MEA) concentration using a modified Kent–Eisenberg model. The model gave satisfactory representation of the experimental data at reasonable average absolute deviations between the experimental and the predicted CO2 partial pressures of 11.9% and 7.9%, for the binary and ternary systems, respectively.

In this work, we reported the molar heat capacities, CP, of aqueous solutions of the sterically hindered amines 2-amino-2-methyl-1, 3-propanediol (AMPD), and its aqueous ternaries containing piperazine (PZ) or lithium bromide (LiBr). Measurements were performed in the temperature range 303.15 K to 353.15 K and atmospheric pressure by heat flow differential scanning calorimetry. The excess molar heat capacities, CP E , of the binary solutions were determined, and the data were represented as function of temperature and composition using a RedlichKister-type equation. The CP of the ternary mixtures was correlated with temperature and amine concentration using the Sohnel and Novotny equation. Results showed that the calculated data agree very well with experimental CP values at average absolute deviation values of less than 0.2%.

The mutual diffusion coefficients of aqueous solutions of new polyamine CO 2 absorbents, namely 3-(methylamino)propylamine, diethylenetriamine, N,N,N′,N′-tetramethylethylenediamine, and tetramethyl-1,3-diaminopropane at different concentrations were measured at temperatures from 303.15 to 323.15 K using the Taylor dispersion technique. Empirical and semi-theoretical models such as a modified Snijder et al. equation, UNIDIF equation, and a free-volume relation based on the rough hard-sphere theory were used to represent the experimental diffusion coefficient data as function of temperature and amine concentration. Densities and viscosities of the aqueous solutions, which were used in the calculation of diffusion coefficients, were also measured. The obtained density and viscosity data were correlated with temperature and amine concentration using a Redlich–Kister-type and Vogel–Tamman–Fulcher equation, respectively. The predicted density, viscosity, and diffusion coefficient data were in reasonable agreement with the experimental data, suggesting that the measured properties were satisfactorily represented by the applied models.

In this study, we present a new set of Henry’s constant data for the system carbon dioxide-aqueous deep eutectic solvent (DES) (20 to 80 wt% DES) at T = (303.15, 308.15, and 313.15) K. The DESs used were choline chloride-based: ethaline (choline chloride/ethylene glycol), glyceline (choline chloride/glycerol), and maline (choline chloride/malonic acid). A differential Henry’s coefficient model was used to describe the behaviour of Henry’s constant, and correlate it with temperature and concentration of DES in the aqueous DES solution. The correlation was found satisfactory such that the proposed model can be used in engineering calculations with reasonable accuracy.

The molar heat capacities, CP, of two new potential polyamine CO2 absorbents: diethylenetriamine (DETA) and 3-(methylamino)propylamine (MAPA), their aqueous binaries, and aqueous ternaries containing piperazine (PZ) were measured at temperatures from 303.15 K to 353.15 K. Measurements were performed at atmospheric pressure by heat flow differential scanning calorimetry. A linear relation suitably represented the temperature dependence of the CP of pure amines. The excess molar heat capacities, C P E , of the binary solutions were investigated, and the data were represented as function of temperature and composition using a Redlich–Kister-type equation. The CP of the ternary mixtures was correlated with temperature and amine concentration using the Sohnel and Novotny equation. Results showed that the calculated data agree very well with the experimental CP values at average absolute deviation values of 0.13%, 0.20, and 0.06 for the pure, binary, and ternary systems, respectively.

[Cd2(C13H15N5)2I4], triclinic, P1̄ (no. 2), a = 8.1348(16) Å, b = 10.1716(17) Å, c = 11.645(3) Å, α = 76.485(18)°, β = 77.750(19)°, γ = 74.030(16)°, V = 889.4(3) Å3, Z = 1, R gt(F) = 0.0597, wR ref(F 2) = 0.1251, T = 293(2) K.

A widely utilized spinal implant material, polyetheretherketone (PEEK), with its bio-inert and hydrophobic surface was persistently paid attention for bioactive surface modification. Hydroxyapatite (HAp), exhibiting excellent osteoconductive property, has also been regarded as a promising candidate for biomedical applications. The present study employed an arc ion plating (AIP) technique to respectively deposit rutile-rich titanium dioxide (R-TiO2) and anatase-rich titanium dioxide (A-TiO2) as an interlayer onto PEEK substrates for inducing HAp layer growth in simulated body fluid (SBF) at low temperature. Consequently, this materials are expected to promote osteoblast compatibility for PEEK to be used as spinal implants. For comparison, microstructure characterization of the as-grown HAp are examined and growth mechanism is proposed. Finally, osteocompatibility test are carried out to evaluate the effect of HAp grown on the TiO2-coated PEEK specimens. Experimental results showed that HAp growth can effectively be enhanced by adopting TiO2 interlayer in SBF environment, with the crystallinity and film thickness of the grown HAp layer proportional to immersion time. It was also worth to note that the R-TiO2/PEEK specimen exhibit superior ability to induce HAp formation, due most likely to the pre-absorbed negatively charged –OH− groups on R-TiO2 coating surface at early growth stage. This also accounts for the ultimate osteocompatibility provided by the R-TiO2 as the interlayer for growing the fastest and the highest crystallinic HAp.

Experimental measurements on the solubility of carbon dioxide in choline chloride–urea (1:2 mole ratio) deep eutectic solvent at temperatures from 303.15 to 343.15 K and pressures up to approximately 6.0 MPa were presented. Measurements were done in a thermogravimetric microbalance and buoyancy effects were accounted for. The solubility of CO2 in the DES decreased with increasing temperature. It was also found to increase as the pressure increased at constant temperature. The solubility data were accurately represented as a function of temperature and pressure using an extended Henry's law equation at average absolute deviation of 1.0%.

In this work, we report new experimental data on density, ρ, refractive index, nD, and viscosity, η, of two deep eutectic solvents, N,N-diethylethanol ammonium chloride–glycerol (DEACG) and N,N-diethylethanol ammonium chloride–ethylene glycol (DEACEG), and their aqueous solutions, over the complete composition range, at temperatures from (298.15 to 343.15) K. Densities and viscosities were measured using the vibrating tube and the falling ball techniques, respectively, while the refractive index at the sodium D line was measured using an automatic refractometer. We aimed to represent the measured properties as a function of temperature and composition, and correlated them using the Redlich–Kister-type equation, for density, a polynomial function, for refractive index, and the Vogel–Fulcher–Tammann (VFT) equation, for viscosity.

In this study, we report new experimental measurements on the solubility of carbon dioxide in aqueous blended amine solutions containing diethylenetriamine (DETA) and piperazine (PZ) (at 30 wt% total amine concentration). Solubility data for CO2 in aqueous DETA solutions at several concentrations (20, 30, 40) wt% are also presented. Measurements were performed in a vapor-liquid equilibrium apparatus at temperatures (313.2, 333.2, 353.2) K and pressures up to around 900 kPa. It was found that the solubility of CO2 in the systems studied were appreciably higher than in typical amine solvents. A modified Kent–Eisenberg model was used to correlate the obtained solubility of CO2 (expressed as mole CO2 per mole amine) in the solvent with CO2 partial pressure, temperature, and amine concentration. The model gave satisfactory representations of the solubility data at reasonable average absolute deviations between the experimental and the calculated values (of CO2 partial pressures) of 16% and 17%, for the binary and ternary systems, respectively.

In this study, a new set of data on the vapor pressure of aqueous blends of the most industrially important amines monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), methyldiethanolamine (MDEA), 2-amino-2-methyl-1-propanol (AMP), and piperazine (PZ) were presented. The blended-amines systems are mixtures of (TEA/AMP/MDEA) + (MEA/DEA/PZ), at total amine concentration = 30 wt% (10 wt% amine 1 + 20 wt% amine 2). Experimental data were obtained at atmospheric pressure and temperatures (303.15–343.15) K using a vapor pressure measurement apparatus. The apparatus consisted mainly of a degassing system and a vapor pressure measurement setup where the equilibrium experiment was performed. The vapor pressures of aqueous solutions of each of the six single-amine systems were also presented. Results showed that the addition of amine in water lead to the lowering of the vapor pressure. The vapor pressure increased with increasing temperature, and decreased with increasing mole fraction of amine in the solution. The vapor pressure data were correlated with temperature using the reliable Antoine equation, which yield an average absolute deviation of 0.09% for the aqueous single-amine systems, and 0.13% for the aqueous blended amine systems. The results presented in this work can be applied in engineering design calculations to have reliable vapor pressure estimates for the investigated amine systems in the temperature range (303.15–343.15) K.

As part of our systematic study on physicochemical characterization of (glycol + amine) systems, thermophysical properties, including refractive index, density, and electrolytic conductivity measurements were carried out on aqueous systems containing glycol and 2-amino-2-hydroxymethyl-1,3-propanediol (TRIS). The glycols studied are diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (T4EG). The measurements were done over a temperature range of (298.15 to 343.15) K at normal atmospheric pressure. Different concentrations (4 to 16)% by weight TRIS or (56 to 44)% water, in a fixed amount 40% glycol were used. The influences of temperature and compositions on the measured properties are discussed and then correlated based on the equation proposed for aqueous (glycol + salt) systems. Calculated results show that the applied model is satisfactory in representing the measured properties in the aqueous systems containing the glycols and TRIS.

In this present work, a thermophysical property characterization of aqueous ternary system containing n-tris-[hydroxymethyl]methyl-3-aminopropanesulfonic acid (TAPS) and glycol was done. Thermophysical properties, including refractive index, density, and electrolytic conductivity, measurements were considered. The glycols considered are propylene glycol (PG), dipropylene glycol (DPG), and tripropylene glycol (TPG). The measurements were done over a temperature range of 298.15 K to 343.15 K and at normal atmospheric pressure. Different concentrations (4% to 16% by weight TAPS or 56% to 44% water, in a fixed amount of glycol – 40%) were used. The effects of temperature and compositions on the measured properties were discussed and then correlated based on the equation proposed for aqueous salt–glycol systems. Calculation results show that the applied model was satisfactory in representing the measured properties in the aqueous ternary systems containing TAPS and considered glycols.

Rhodococcus sp. strain p52, a previously isolated dibenzofuran degrader, could effectively inhibit the growth of cyanobacteria, including species of Microcystis, Anabaena, and Nodularia. When strain p52 was inoculated at the concentration of 7.7×10(7) CFU/ml, 93.5% of exponentially growing Microcystis aeruginosa (7.3×10(6) cells/ml initially) was inhibited after 4 day. The threshold concentration for its algicidal activity against M. aeruginosa was 7.7×10(6) CFU/ml. Strain p52 exerted algicidal effect by synthesizing extracellular substances, which were identified as trans-3-indoleacrylic acid, DL-pipecolic acid, and L-pyroglutamic acid. The effective concentrations of trans-3-indoleacrylic acid and DL-pipecolic acid against M. aeruginosa were tested to be 0.5 mg/l and 5 mg/l, respectively.

In this work, we present new measurements on the solubility of carbon dioxide in a deep eutectic solvent (DES) containing choline chloride and glycerol (1:2 mole ratio) over the temperature range (303.15 to 343.15) K and pressures up to 6.3 MPa. Experimental measurements were carried out in a thermogravimetric microbalance, and the effects of buoyancy on the measurements were accounted for. Results indicated that the solubility of the gas in the solvent increased almost linearly with pressure and decreased with increasing temperature. The dependence of the carbon dioxide solubility in the DES (in molality) on temperature and pressure were accurately represented by an extended Henry’s law model at an average absolute deviation of 1.4%.

A type of bi-functional hybrid catalyst of Pd-decorated CNT-promoted Cu-ZrO 2 admixed with HZSM-5 zeolite was developed, and displayed excellent performance for the direct synthesis of dimethyl ether (DME) from CO 2 /H 2 via CH 3 OH in a single fixed-bed continuous flow reactor. Over a CuZr–PdCNTs/HZSM-5 hybrid catalyst under reaction conditions of 5.0 MPa, 523 K, V (H 2 )/ V (CO 2 )/ V (N 2 ) = 69/23/8, GHSV = 25,000 mL STP /(h g-hydr. catal.), the observed specific rate of CO 2 hydrogenation-conversion reached 0.39 μmol/(s m 2 -Cu 0 -SA), which was 1.22 times that of the corresponding Pd/CNTs-free counterpart CuZr/HZSM-5. The addition of a minor amount of the Pd-decorated CNTs into the CuZr/HZSM-5 host catalyst caused little change in the apparent activation energy for CO 2 hydrogenation, but led to an increase of metal Cu exposed area (catalytically active Cu surface-sites closely associated with the CO 2 hydrogenation to methanol) and marked improvement of adsorption performance of the catalyst for H 2 and CO 2 . The latter would help generate a micro-environment with higher concentration of active H and CO 2 adspecies at the surface of the functioning catalyst, thus increasing the rate of the surface hydrogenation reactions. The present study also demonstrated that combining the methanol-synthesis and methanol-dehydration-to-DME processes in heterogeneous “one-pot” reactions by using the bi-functional hybrid catalyst could indeed enhance the driving force for CO 2 hydrogenation conversion.

The solubility of carbon dioxide in a eutectic mixture containing choline chloride and ethylene glycol was determined for temperatures 303.15–343.15 K and pressures up to 6 MPa using a thermogravimetric microbalance. The effects of buoyancy on the experimental measurements were accounted for. Buoyancy corrections were estimated by using a highly accurate equation of state in the calculation of the density of carbon dioxide, and a Tait-type equation in estimating the density of the deep eutectic solvent. An extended Henry's law equation was applied to accurately represent the solubility of carbon dioxide in the DES (in molality) as a function of temperature and pressure.

New measurements are reported for the densities of choline chloride: urea (REL) deep eutectic solvent and its aqueous mixtures over the temperature range (298.15 to 323.15) K and pressures up to 50 MPa. The experimental data were used to derive other properties such as isothermal compressibility, isobaric expansivity and excess molar volume. A Tait-type equation was used to correlate accurately the high-pressure density data to temperature, T, pressure, P, and composition, x. The excess molar volumes of {REL (1) + H2O (2)} mixtures were also investigated and represented as a function of all three variables, T, P, x, using an empirical equation. Results indicate that the correlations used in this work can be satisfactorily used to predict the densities of the studied systems at different conditions of temperature, pressure and composition.

The densities of the deep eutectic solvent (DES) based on choline chloride and ethylene glycol (Ethaline) and its mixtures with water were measured from 298.15 K to 323.15 K over an extended pressure range (0.1–50) MPa. Other important properties such as isothermal compressibility and isobaric expansivity were derived for the pure system using the experimental data. The high-pressure densities were accurately correlated to the temperature, pressure and composition using a Tait-type equation. For the binary mixtures of Ethaline (1) + H2O (2), the excess molar volumes were investigated and represented as a function of temperature and composition by a Redlich–Kister-type equation. Results indicated that the correlations proposed in this work can be used to accurately predict the densities of the studied systems as functions of temperature, pressure and composition.

A new set of vapor pressure data for the aqueous solutions of ethaline, glyceline, maline, and reline at different temperatures (30, 40, 50, 60, and 70 °C) and concentrations (20, 40, 60, and 80 wt%) are presented. The data successfully fit the classic Antoine equation, for the temperature-dependence of the vapor pressure, and a Volger–Tamman–Fulcher-type equation, for the concentration-dependence of the vapor pressure. The % AADs for the experimental and calculated data were all less than 0.5%.

A new set of molar heat capacity data for aqueous {2-amino-2-hydroxymethyl-1,3-propanediol (TRIS) + glycol} at (30 to 80) °C and different concentrations (4% to 16% by weight TRIS or 56% to 44% by weight water, in a fixed amount of glycol – 40% by weight) were gathered via reliable measurement method and are presented in this report. The glycols considered were diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (T 4 EG), propylene glycol (PG), dipropylene glycol (DPG), and tripropylene glycol (TPG). The 198 data points gathered fit the equation, C p = C p,a + B 1 m + B 2 m 2 + B 3 m 3 , where C p and C p,a are the molar heat capacities of the (TRIS + glycol + water) and (water + glycol) systems, respectively, B i the temperature-dependent parameters, and m the mole TRIS per kilogram (glycol + water). The overall average absolute deviation (AAD) of the experimental data from the corresponding values calculated from the correlation equation was 0.07%.

Deep eutectic solvents (DES) are new emerging alternatives to conventional ionic liquids that may find a number of interesting applications in industrial and chemical processes. In this study, the densities, ρ, and refractive indices, nD, of the DESs (choline chloride + ethylene glycol) and (choline chloride + glycerol) and their aqueous mixtures were investigated at atmospheric pressure over the temperature range 298.15–333.15 K and across a complete composition range. The excess molar volumes, VE, and refractive index deviations, ΔnD, were also calculated from experimental results. The calculated excess molar volumes were negative at all temperatures over the entire range of composition considered, suggesting the presence of strong interactions between water and the DES in the mixtures. The refractive index deviations, on the other hand, were found positive in the entire concentration range. The calculated properties were fitted to a Redlich–Kister type equation to correlate them to the temperature and composition. The correlations used satisfactorily represent the densities and refractive indices of the pure DESs and their aqueous binary mixtures as functions of temperature and composition as indicated by the low overall average absolute deviations obtained in the calculations.

The molar heat capacity ( C p ) of a potential solvent system for CO 2 absorption, containing water, glycol and n -[tris(hydroxymethyl)methyl-3-amino]propanesulfonic acid (TAPS), was measured at 30–80 °C and different concentrations via differential scanning calorimetry. Each of the glycols – diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (T 4 EG), propylene glycol (PG), dipropylene glycol (DPG) and tripropylene glycol (TPG) – was mixed with TAPS + H 2 O to form ternary systems consisting of a fixed amount of the glycol (40 mass%) and variable TAPS/H 2 O proportions (4–16 mass% TAPS or 56–44% H 2 O). An extended Redlich–Kister -type equation was used to correlate heat capacity with concentration and temperature; the average absolute deviation (AAD) of the 198 data points from the corresponding values predicted by the correlation was 0.04%. The new set heat capacity data or the correlation, reported for the ternary system considered, can be used with high degree of accuracy in process design calculations for systems that will utilize these solvent systems.