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This paper reviews recent Monte Carlo simulations within the empirical potential approach, which give insights into fundamental aspects of the bulk and surface structure of group-IV semiconductor alloys containing carbon. We focus on the binary Si_1-xC_x and ternary Si_1-x-yGe_xC_y alloys strained on silicon substrates. The statistical treatment of these highly strained alloys is made possible by using the semigrand canonical ensemble. We describe here improvements in the algorithm which considerably speed up the method. We show that the identity switches, which are the basic ingredients in this statistical ensemble, must be accompanied by appropriate relaxations of nearest neighbors in order to reach "quasiequilibrium" in metastable systems with large size mismatch between the constituent atoms. This effectively lowers the high formation energies and large barriers for diffusion which make molecular dynamics methods impractical for this problem. The most important findings of our studies are: (a) The prediction of a repulsive Ge–C interaction and of a preferential C–C interaction in the lattice. (b) The prediction for significant deviations of the structural parameters and of the elastic constants from linearly interpolated values (Vegard's law). As a result, for a given amount of carbon, strain compensation is shown to be more drastic than previously thought. (c) Investigation of the surface problem shows that the competition between the reconstruction strain field and the preferential arrangement of carbon atoms leads to new complicated structural patterns.

Solubility of tetragonal lysozyme crystal was measured by using two different methods. The solubility measured by using growth rates of the crystal corresponded well to that measured by using change in the concentration of the supernatant of the solution. Our data also corresponded well to the data obtained by Sazaki et al. and Gray et al., while not to those obtained by Howard et al. and Rosenberger et al. The discrepancies are due to the difference in the principles of the methods. We also checked effects of different initial concentrations on the solubility. Contrary to previous reports, the solutions of the different initial concentrations did not reach equilibrium when their concentrations attained to a same value.

The activity and solubility of Si in Mo solid solution were studied by the first-principles calculations and quasi-harmonic approximation. The lattice constants, bulk modulus, and formation enthalpies of Mo-Si intermetallics were investigated, and the thermodynamic properties of Mo were also calculated. The Si activity coefficient ${\gamma }_{\mathrm{\text{Si}}}$ is approximately 10${}^{-16}$ at 100 K, while it increases by about 15 orders of magnitude over the investigated temperature range (100–2000 K). It is clear that Si activity coefficient in Mo solid solution increased rapidly with the increasing temperature, which should be ascribed to the Si–Mo interaction being evidently stronger than Mo–Mo interaction. According to the calculated thermodynamic properties, the solubility curve of Si in Mo solid solution was also predicted. The solubility limit of Si in Mo solid solution is $\sim$5.5 at.%, which agrees well with the other experiment and assessed results.

The elemental sulfur solubility in sour gas plays an important role in H₂S-rich gas reservoir development and transportation. While the solubility of elemental sulfur in sour gas can be measured in macroscopical respect, the interaction of solid deposition is not clear at microscale. In this work, molecular dynamic simulation (MD) was adopted to predict the solubility of elemental sulfur in hydrogen sulfide at nanoscale. It is found that the results of new nanoscale solubility model are close to the reported experimental data. The average relative error of the solubility of elemental sulfur in hydrogen sulfide by using the new model is 11.05% compared with the experimental data. Therefore, the new model can be used to predict the solubility of elemental sulfur in hydrogen sulfide.

During the past 20 years, supercritical fluid (SCF) based technologies have been gaining an increasing attention through the academic and industrial communities due to its advantages. One of the most important parameter for any supercritical-based technologies is the knowledge of the solute solubility at different pressures and temperatures. But, due to several concerns e.g. time and expense, measuring the solubility of all compounds in wide ranges of temperature and pressure is not possible. Respect to this, a new empirical correlation with four fitting parameters has been proposed to correlate the solubility of pharmaceuticals in different temperatures and pressures. The obtained results compared with four widely used density based correlations including Mendez-Santiago and Teja (MST), Bartle et al., Chrastil, Kumar and Johnston (KJ) revealed rather good capability of the proposed simple correlation for predicting the solubility of solutes in supercritical carbon dioxide (SC-CO₂). At last, the obtained results compared with the results of three Equations of State (EoS's) with three different mixing rules.

Organo-soluble fluorinated polyimides were synthesized by the polycondensation of a new aromatic diamine α,α-bis(4-amino-3,5-dimethylphenyl)-4′-fluorophenyl methane with several aromatic dianhydrides. The one-step polymerization procedure was conducted at 180°C in m-cresol, producing the polyimides with inherent viscosities of 0.68–0.76 dL· g^-1. The polyimides could be soluble not only in polar aprotic solvents, such as N-methyl-2-pyrrolidinone, and N,N-dimethylacetamide, but also in common organic solvents, such as chloroform, cyclopentanone, m-cresol and so on. The polyimide films show excellent transparency with the UV-Vis cut-off lengths of 310–360 nm and light transmittances of higher than 80% in the visible region. In addition, the polyimides exhibit good thermal stability with an initial decomposition temperature (T_d) higher than 530°C and have more than 60% of residual weight retentions at 700°C.

An aromatic diamine monomer, 4,4′-bis(3-amino-5-trifluoromethyl phenoxy)-biphenyl (TFBPDA), was synthesized via the nucleophilic displacement reaction of 3,5-dinitrobenzotrifluoride and 4,4′-biphenol. The monomer was reacted with various aromatic dianhydrides via the high temperature polycondensation procedure to provide a series of polyimides. The polyimides, PI-1 to PI-4, show good solubility not only in aprotic solvents, such as N-methyl-2-pyrrolidinone and N,N-dimethylacetamide, but also in many common solvents, such as m-cresol, chloroform and cyclopentanone. PI-4, derived from 4,4′-(hexafluoroisopropylidene)diphthalic anhydride and TFBPDA, was even soluble in toluene. Moreover, PI films exhibit good thermal stability, outstanding transparency in the visible light region and acceptable mechanical and electrical properties. The excellent combined properties of the polyimides make them as a good candidate for fabricating microelectronics.

A novel unsymmetrical fluorinated diamine monomer with kink non-coplanar heterocyclic structures, 1,2-dihydro-2-(4-amino-2-trifluoromethylphenyl)-4-[4-(4-amino-2-trifluoromethylphenoxy)phenyl](2H)phthalazin-1-one, was prepared through the nucleophilic substitution reaction of 1-trifluromethyl-2-chloro-5-nitrobenzene with 1,2-dihydro-4-(4- hydroxyphenyl)(2H)phthalazin-1-one in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd-C. A series of new fluorinated polyamides were synthesized by the phosphorylation polyamidation of the fluorinated diamine with various dicarboxylic acids. The prepared polymers were obtained in quantitative yields with moderately and high inherent viscosities (0.47–0.87 dL/g). They were all amorphous and readily soluble in various polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacctamide (DMAc), pyridine (Py) and m-cresol at room temperature. These fluorinated polyamides have excellent thermal properties. The glass transition temperatures were all above 300°C. The 5% and 10% weight loss temperatures were in the range of 437–466°C and 482–525°C in nitrogen atmosphere, respectively.

A novel cross-linking process using two high molecular weight aromatic poly(thioether)s, which were synthesized by the reactions of 4,4′-thiobisbenzenethiol with 4,4′-difluorobenzophenone and 4,4′-difluorodiphenylsulfone, respectively, and commercially available lower molecular weight poly(p-phenylene sulfide) was investigated. These reactions were carried out in bulk by the addition of silver tetrafluroborate and α,α′-dibromo-p-xylene at 190°C over a period of 45 min. Furthermore, the same procedure could be modified to cross-link compression-molded films of these three polymers. The thermal and solubility behaviors of these polymers before and after cross-linking reactions, are presented.

Chloro ethane dimethyl sulfoxide, C₂H₅Cl·DMSO (ECl·DMSO) was prepared by interaction of acrylic acid with conc. Hydrochloric acid in dimethyl sulfoxide (DMSO) and subsequent decarboxylation with H₂O₂ solution. The formation of the compound was confirmed by spectral and analytical methods; the molecular weight was determined by cryoscopic method. The solubility of poly(vinyl alcohol) (PVA) in different solvents or mixed solvents at 40°C, 50°C and 60°C temperature in the presence of 0.01% of ECl·DMSO was determined. It turned out that ECl·DMSO helps dissolution of PVA, and is very effective catalyst in the preparation of esters and acetals of PVA.

Aromatic copolyamides were synthesized by the Yamazaki phosphorylation method starting from bis(4-carboxyphenyl) phenyl phosphine oxide, terephthalic acid and 4,4′-diaminodiphenyl methane. The copolymers with inherent viscosities of 0.52–0.99 dL/g were obtained. The structures of the copolyamides were characterized by elemental analysis, FTIR and NMR. The glass transition temperatures were measured by DSC and DMA, respectively, and the results showed that the T_gs of the polymers were higher than 287°C. Thermal decomposition temperatures of the copolyamides at 5% weight loss were found in the range of 423–469°C by TGA. Most of the copolymers were readily soluble in a variety of organic solvents such as NMP, DMAc, m-cresol and so on. The tensile experiments of the thin films showed that the polymers had good mechanical properties.

The synthesis and behavior in homogeneous solutions of 2,3,9,10,16,17,23,24-octakis(3-phthalimidopropyloxy)phthalocyaninatozinc(II) (5) and 2,3,9,10,16,17,23,24-octakis(3-aminopropyloxy)phthalocyaninatozinc(II) (6) are reported.

Gold(III) compounds continue to be explored for their potential utility as anticancer agents. A recognized limitation is the reactivity of gold(III), which is typically reduced to the more labile gold(I) state under physiological conditions. The use of porphyrins can overcome this problem. However, to date the stabilization provided by the use a strongly chelating porphyrin is offset by the poor solubility of the resulting complex in aqueous media. In this work, we describe the synthesis and in vitro anti-cancer activity of a gold(III)porphyrin complex with relatively good aqueous solubility. As judged from standard antiproliferation assays, this complex displays an IC₅₀ of 9 μM for the A2780 human ovarian cancer cell line. This is a higher level of potency than displayed by two related control systems.

Four novel $\beta$-dialkylated porphycenes, $i.e$. 2,12-(DEPoT and DPPoT) and 2,17-(DEPoC and DPPoC) were realized for the first time in porphycene chemistry. Unsymmetrically substituted monoalkylbipyrrole dialdehydes were subjected to McMurry coupling reactions to produce the isomeric $\beta$-dialkylated porphycenes. All these porphycenes exhibit unexpectedly good solubility in common organic solvents. The positional effects of alkyl groups could be controlled through diversification in structure of porphycene cores and, as a result, their photophysical properties. DPPoT presents significant fluorescence accompanied by reasonable singlet oxygen generation ability.

To investigate the solubility of porphyrin derivatives, their intermolecular interaction energies were calculated by the counterpoise method at the B97D3/6-31G(d) level. It was found that the calculated intermolecular interaction energies corresponded to the solubility measured by UV-vis spectroscopy. This correlation was consistent with differences in substituents and in the metals in the porphyrin core.

Tetrabenzocorrolazine dyes with high color strength and broad absorbance derived from a phthalocyanine moiety were designed and synthesized for a color filter on an array-mode black matrix of low dielectric constant. The prepared tetrabenzocorrolazine dyes focused the absorbance of phthalocyanine further into the visible light range so that the color was considerably closer to black, while making it easier to introduce an axial substituent in the vertical direction to the dye main body, thereby markedly improving its solubility in industrial solvents. Upon mixing with a perylene dye of 450-550 nm absorbance and a thermosetting resin composition, dye-based black matrix films with high optical density values, associated with superior light shielding capability, were fabricated. The prepared black matrix films not only ensured thermal resistance by allowing easy intermolecular cohesion but also served as an insulating membrane that did not interfere with the thin film transistor electric signals, exhibiting a value of 3-5 when dielectricity was measured as the most critical factor for the color filter on array mode display panels.

A Suzuki–Miyaura coupling reaction was performed to synthesize 5,15-meso-bis(2-chlorothiophen-3-yl)porphyrins in order to obtain a building block for further functional porphyrins. Photophysical and electrochemical properties were investigated to understand the effect of 2-chloro substituted thiophenes which are connected at their 3-position to the meso-position of the porphyrin. A computational calculation with counterpoise method was demonstrated to estimate the relative intermolecular interaction in order to compare solubility. Installed chloro atoms at the 2-position of thiophen-3-yl decreased in intermolecular interaction which caused an increase in solubility.

In enhancing the durability and photovoltaic performance of Perovskite solar cells, Hole transport Materials (HTMs) play the key role. In search of new HTMs, in this work, we have designed, synthesized and characterized 3,4,5 trimethoxy phenoxy substituent free-base soluble phthalocyanine (H₂-TmPc) along with their metallo derivates with Cu(II) (Cu-TmPc) and Zn(II) (Zn-TmPc) derivatives and applied them as HTMs for PSC. All three HTMs were characterized by optical, electrochemical, thermal and impedance studies. Absorption spectra in chlorobenzene revealed two Q bands and a soret band whereas metallo derivatives showed a single Q and soret band. Electrochemical studies revealed that these HTMs are capable of extracting holes from the Perovskite layer. Impedance studies showed that Cu-TmPc showed high specific conductance of 1.78× 10${}^{-5}$ when compared to other derivatives. Based on these data PSCs were fabricated with these Pc series as HTMs and SnO₂ as ETL layer and noticed that Cu-TmPc gave a power conversion efficiency of 5.7%.

Metal-free photocatalysts trithiocyanuric acid (C₃N₃S${}_3)$ and its polymers were one-step synthesized and used for selective aerobic oxidation of benzyl alcohol under visible light. The S–S bridged C₃N₃S₃ polymers showed higher oxidation activity with increasing polymerization time and reached a maximum at 40h. As a major factor, catalysts’ solubility in water at different temperatures (from 298.15K to 368.15K) was measured at atmospheric pressure. The obtained data were correlated by polynomial empirical equation and modified Apelblat equation, respectively. Experimental results proved that the solubility of C₃N₃S₃ and its polymers increased with increasing temperature. The solubility of C₃N₃S₃ polymers with lower polymerization degree (DP) were better than that of parent C₃N₃S₃ owing to the hydrophilicity caused by a low symmetry and disorder structure, whereas the higher DP could lead to the decrease of polymer solubility and further affect the photocatalytic activity. Thermodynamic properties of the solution system including the enthalpy ($\mathrm{\Delta }{H}_S^0)$ and heat capacity ($c_p^0$) were calculated by the modified Apelblat equation.

The present study outlines a straightforward approach for designing a novel drug delivery system based on bacterial nanocellulose composites containing curcumin-loaded graphene quantum dots (BNC/CUR/GQDs) for antibacterial and wound healing applications. The nanocomposite was made of interconnected plates with uniform thicknesses around 2mm. The scanning electron microscope (SEM) image of the prepared BNC nanocomposite showed a uniform and porous morphology composed of the microfibrils having an average diameter of 120nm, which contributes to both drug inclusion and drug release in a controllable fashion. The designed system biosynthesized by Acetobacter xylinum demonstrated an optimum drug loading capacity and controlled release profile. The drug loading content and drug release efficiency were calculated around 31% and 61%. Agar diffusion test indicated that the introduction of GQDs into the BNC matrix conspicuously improved the growth inhibition of bacteria, and gram-negative and gram-positive bacterial strains were measured 21.6mm and 21.5mm, respectively. The cell viability of 92.3% was obtained for the BNC, while the cell viability of the designed system was measured at around 88.07%. Consequently, the incorporation of curcumin-loaded graphene quantum dots into bacterial nanocellulose matrices can open up a new insight into the production of high-performance wound dressing supplies.