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The existence of propane (C[sub.3]H[sub.8]) in a CO[sub.2]-oil mixture has great potential for increasing CO[sub.2] solubility and decreasing minimum miscibility pressure (MMP). In this study, the enhanced solubility, reduced viscosity, and lowered MMP of CO[sub.2]-saturated crude oil in the presence of various amounts of C[sub.3]H[sub.8] have been systematically examined at the reservoir conditions. Experimentally, a piston-equipped pressure/volume/temperature (PVT) cell is first validated by accurately reproducing the bubble-point pressures of the pure component of C[sub.3]H[sub.8] at temperatures of 30, 40, and 50 °C with both continuous and stepwise depressurization methods. The validated cell is well utilized to measure the saturation pressures of the CO[sub.2]-C[sub.3]H[sub.8]-oil systems by identifying the turning point on a P-V diagram at a given temperature. Accordingly, the gas solubilities of a CO[sub.2], C[sub.3]H[sub.8], and CO[sub.2]-C[sub.3]H[sub.8] mixture in crude oil at pressures up to 1600 psi and a temperature range of 25–50 °C are measured. In addition, the viscosity of gas-saturated crude oil in a single liquid phase is measured using an in-line viscometer, where the pressure is maintained to be higher than its saturation pressure. Theoretically, a modified Peng–Robinson equation of state (PR EOS) is utilized as the primary thermodynamic model in this work. The crude oil is characterized as both a single and multiple pseudo-component(s). An exponential distribution function, together with a logarithm-type lumping method, is applied to characterize the crude oil. Two linear binary interaction parameters (BIP) correlations have been developed for CO[sub.2]-oil binaries and C[sub.3]H[sub.8]-oil binaries to accurately reproduce the measured saturation pressures. Moreover, the MMPs of the CO[sub.2]-oil mixture in the presence and absence of C[sub.3]H[sub.8] have been determined with the assistance of the tie-line method. It has been found that the developed mathematical model can accurately calculate the saturation pressures of C[sub.3]H[sub.8] and/or CO[sub.2]-oil systems with an absolute average relative deviation (AARD) of 2.39% for 12 feed experiments. Compared to CO[sub.2], it is demonstrated that C[sub.3]H[sub.8] is more soluble in the crude oil at the given pressure and temperature. The viscosity of gas-saturated crude oil can decrease from 9.50 cP to 1.89 cP and the averaged MMP from 1490 psi to 1160 psi at 50 °C with the addition of an average 16.02 mol% C[sub.3]H[sub.8] in the CO[sub.2]-oil mixture.

An experimental and theoretical investigation of the reaction between chlorine atoms and propane/deuterated propane (C[sub.3]H[sub.8]/C[sub.3]D[sub.8]) was performed. The experimental work aimed to determine absolute and site-specific rate constants for hydrogen and deuterium abstraction in the Cl + C[sub.3]H[sub.8]/C[sub.3]D[sub.8] system. Measurements were conducted using the relative rate method at three temperatures between 298 and 387 K. Total rate constants for H/D abstraction by chlorine, as well as individual rate constants for abstraction from primary and secondary carbon sites, were obtained. The kinetic data for H abstraction agree well with previously reported literature values, confirming the reliability of the experimental approach. Notably, rate constants for the C[sub.3]D[sub.8] + Cl reaction were determined for the first time, and the consistency of these results supports the reliability of the newly derived kinetic parameters. In the theoretical part of the study, hydrogen/deuterium abstraction from propane by atomic chlorine was analyzed within an atmospheric-chemistry context to clarify temperature dependence and site selectivity. Stationary points (SC, TS, PC, reactants, products) were optimized at MP2/aug-cc-pVDZ and verified by harmonic frequencies and intrinsic reaction-coordinate analyses. Eyring transition-state theory yielded 298–550 K rate constants with activation free energies referenced to SC. Our calculations indicate entrance-channel complex formation and effectively barrierless progress for most pathways; a small barrier appears only for RD1′. L-parameter evaluation classifies TS2 as reactant-like, and branching ratios identify –CH[sub.2]– abstraction (RX2) as dominant. These findings align with the experimental data.

Amyloid A (AA) amyloidosis, a complication of chronic inflammatory conditions, develops when proteolytic fragments of serum amyloid A protein are deposited in tissues as amyloid fibrils. This placebo-controlled trial investigated the effect of eprodisate, a small molecule that inhibits amyloid fibril polymerization and tissue deposition in patients with renal AA amyloidosis. As compared with placebo, the drug slowed a decline in renal function. Eprodisate is a member of a new class of compounds that interfere with interactions between amyloidogenic proteins and glycosaminoglycans. This trial investigated the effect of eprodisate, a small molecule that inhibits amyloid fibril polymerization and tissue deposition in patients with renal AA amyloidosis. As compared with placebo, the drug slowed a decline in renal function. The amyloidoses constitute a group of diseases in which proteins are deposited extracellularly in the tissues as insoluble fibrils, causing progressive organ dysfunction and death. 1 Amyloid A (AA) amyloidosis, also referred to as secondary amyloidosis, is a rare but serious complication of chronic inflammatory diseases and chronic infections. The amyloidogenic protein in AA amyloidosis is a proteolytic fragment of serum amyloid A protein (SAA), an acute-phase reactant produced by the liver. The kidney is the organ most frequently affected in AA amyloidosis. 2 Ongoing deposition of amyloid in the kidney results in proteinuria and progressive loss of renal function. The gastrointestinal . . .

A series of hollow VO.sub.x/SiO.sub.2 nanofiber catalysts (nV/S-f) with vanadium content ranging from 0.25 wt% to 4.0 wt% were prepared by electrospinning-calcination, and characterized by ICP-MS, XRD, N.sub.2 adsorption-desorption, SEM, XPS, UV-Vis-DRS and H.sub.2-TPR. Subsequently, the performance of these catalysts in the oxidative dehydrogenation of propane (ODHP) was evaluated. It was found that vanadium species with high dispersivity were obtained when the V content was less than 1.5 wt%. By comparison, 1.0V/S-f catalyst had the best catalytic performance, especially in terms of the propylene selectivity at high-temperature: 77% at 550 °C and 74% at 575 °C. In contrast to the conventional impregnation technique, the catalyst with one-dimensional nanostructure has more catalytic advantages.

A new method for catalysing the cross-coupling of two different aryl electrophiles is described; the principle of this method, which involves cooperation between two metal catalysts that are selective towards different substrates, should be generally useful in catalysis. Multiple catalysts for carbon–carbon bond formation Transition-metal-catalysed strategies for the formation of new carbon–carbon bonds are used to synthesize a broad range of small molecules, including pharmaceutical agents. In cases where a single metal fails to promote a selective or efficient transformation, the synergistic cooperation of two distinct catalysts — multimetallic catalysis — can be used instead. The application of this strategy has mainly been limited to the use of metals with distinct reactivities. These authors demonstrate that cooperativity between a nickel catalyst and a palladium catalyst can be used to couple aryl bromides with aryl triflates directly, eliminating the need to use arylmetal reagents. Each catalyst forms less than 5% cross product in isolation, but with both catalysts present the yields can reach 94%. These results reveal a new, general method for the synthesis of biaryls, heteroaryls, and dienes, and should simplify the synthesis of pharmaceutical agents, many of which are currently made with pre-formed organometallic reagents. The advent of transition-metal catalysed strategies for forming new carbon-carbon bonds has revolutionized the field of organic chemistry, enabling the efficient synthesis of ligands, materials, and biologically active molecules 1 , 2 , 3 . In cases where a single metal fails to promote a selective or efficient transformation, the synergistic cooperation 4 of two distinct catalysts—multimetallic catalysis—can be used instead. Many important reactions rely on multimetallic catalysis 5 , 6 , 7 , 8 , 9 , 10 , such as the Wacker oxidation of olefins 6 , 7 , 8 and the Sonogashira coupling of alkynes with aryl halides 9 , 10 , but this approach has largely been limited to the use of metals with distinct reactivities, with only one metal catalyst undergoing oxidative addition 11 , 12 . Here, we demonstrate that cooperativity between two group 10 metal catalysts—(bipyridine)nickel and (1,3-bis(diphenylphosphino)propane)palladium—enables a general cross-Ullmann reaction (the cross-coupling of two different aryl electrophiles) 13 , 14 , 15 . Our method couples aryl bromides with aryl triflates directly, eliminating the use of arylmetal reagents and avoiding the challenge of differentiating between multiple carbon–hydrogen bonds that is required for direct arylation methods 16 , 17 . Selectivity can be achieved without an excess of either substrate and originates from the orthogonal reactivity of the two catalysts and the relative stability of the two arylmetal intermediates. While (1,3-bis(diphenylphosphino)propane)palladium reacts preferentially with aryl triflates to afford a persistent intermediate, (bipyridine)nickel reacts preferentially with aryl bromides to form a transient, reactive intermediate. Although each catalyst forms less than 5 per cent cross-coupled product in isolation, together they are able to achieve a yield of up to 94 per cent. Our results reveal a new method for the synthesis of biaryls, heteroaryls, and dienes, as well as a general mechanism for the selective transfer of ligands between two metal catalysts. We anticipate that this reaction will simplify the synthesis of pharmaceuticals, many of which are currently made with pre-formed organometallic reagents 1 , 2 , 3 , and lead to the discovery of new multimetallic reactions.

Non-oxidative propane dehydrogenation is an endothermic reaction requiring thermally stable and regenerable catalysts to produce propylene. In this work, we investigate bimetallic Co.sub.XNi.sub.2-XP as an alternative, non-noble metal propane dehydrogenation catalyst. Co.sub.1Ni.sub.1P displayed higher propylene selectivity than Co.sub.2P and higher site-normalized propylene production rates than Ni.sub.2P. Different compositions of Co.sub.XNi.sub.2-XP catalysts were evaluated for propane dehydrogenation with oxidative regeneration in between each cycle. Ni-rich Co.sub.0.5Ni.sub.1.5P showed increased propylene production upon regeneration due to the formation of the Ni.sub.12P.sub.5 phase during reaction. In contrast, Co.sub.1Ni.sub.1P and Co.sub.1.25Ni.sub.0.75P showed the ability to recover > 50% of the initial activity for at least 3 oxidative regenerations, while maintaining high propylene selectivity without any phase change. This study showcases the enhancement in stability and propane dehydrogenation performance of Ni.sub.2P through Co incorporation and Ni:Co ratio control.

DCM was classified as probably carcinogenic to humans (Group 2A) on the basis of limited evidence that it causes biliary-tract cancer and non-Hodgkin lymphoma in humans and sufficient evidence of carcinogenicity in experimental animals (malignant lung and hepatocellular tumours in male and female mice).2,3,6-9 In making its overall assessment, the working group also took into account the strong evidence that DCM metabolism via glutathione-S-transferase T1 (GSTT1) leads to the formation of reactive metabolites, that GSTT1 activity is strongly associated with genotoxicity of DCM in vitro and in vivo, and that GSTT1-mediated metabolism of DCM does occur in humans. DNA reactivity was evident in various genotoxicity assays, including in animals and in human cells in vitro. Because 1,3-PS does not require metabolic activation and reacts directly with DNA and other macromolecules, the working group concluded that this mechanism probably operates both in animals and humans.

Polymerization reactions conducted inside cells must be compatible with the complex intracellular environment, which contains numerous molecules and functional groups that could potentially prevent or quench polymerization reactions. Here we report a strategy for directly synthesizing unnatural polymers in cells through free radical photopolymerization using a number of biocompatible acrylic and methacrylic monomers. This offers a platform to manipulate, track and control cellular behaviour by the in cellulo generation of macromolecules that have the ability to alter cellular motility, label cells by the generation of fluorescent polymers for long-term tracking studies, as well as generate a variety of nanostructures within cells. It is remarkable that free radical polymerization chemistry can take place within such complex cellular environments. This demonstration opens up a multitude of new possibilities for how chemists can modulate cellular function and behaviour and for understanding cellular behaviour in response to the generation of free radicals. A strategy for directly synthesizing unnatural polymers in cells through radical polymerization has now been developed. This approach provides a platform to manipulate, track and control cellular behaviour by the in cellulo generation of macromolecules and a variety of nanostructures.

A series of eight new octahedral rhenium cluster complexes with the general formula trans-[Re[sub.6]Q[sub.8]L[sub.4]X[sub.2]] (Q = S or Se; L = 1,2-Bis(4-pyridyl)ethylene (bpe) or 1,3-Bis(4-pyridyl)propane (bpp); X = Cl or Br) was synthesized and investigated. While bpe is a ligand with a conjugated aromatic system, bpp represents a molecule of opposite type and has independent aromatic systems of the two pyridine rings. It was shown that this difference in the electronic structure of the ligands has a fundamental effect on the electronic structure, electrochemical and luminescent properties of the corresponding cluster complexes. Specifically, the [Re[sub.6]Q[sub.8](bpe)[sub.4]X[sub.2]] complexes in solutions show multiple quasi-reversible electrochemical transitions associated with reduction of the organic ligands. At the same time, the trans-[Re[sub.6]Q[sub.8](bpp)[sub.4]X[sub.2]] complexes show multielectron quasi-irreversible reduction processes, which correlate with the mixed character of the lowest unoccupied molecular orbitals of these complexes. All the obtained new compounds exhibit red photoluminescence. The photophysical parameters (emission lifetimes and quantum yields) measured for the bpp complexes exceed those revealed for bpe complexes by more than an order of magnitude.