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AbstractExisting studies reveal that the shape corners of hexagonal fiber affect the degree of constraint on the matrix material. However, none of these studies included the effect of orientation of hexagonal fibers. In this study, a computational micromechanics model of oriented hexagonal fibers in periodic unidirectional composite materials is established for the determination of effective orthotropic elastic properties of the composite. In the present numerical modeling, the representative unit composite cell including the matrix material and the single oriented hexagonal fiber or random oriented hexagonal fibers is solved by micro-scale finite element analysis with different stress loads and periodic displacement boundary conditions, which are applied along the cell boundary to meet the requirement of straight-line constraint during deformation of the cell. Subsequently, the effective elastic properties of the composite are evaluated for periodic regular packing and random packing using the homogenization approach for investigating the influence of unified orientation and random orientation of the hexagonal fibers on the overall elastic properties of the fiber-reinforced composites. The numerical results are verified by comparing with other available results.

Renal cell carcinoma (RCC) is one of the most aggressive urologic cancers, however, the mechanism on supporting RCC carcinogenesis is still not clear. By using gene expression profile analysis and functional clustering, PDZ domain-containing 1 (PDZK1) was revealed to be downregulated in human clear cell renal cell carcinoma (ccRCC) samples, which was also verified in several independent public ccRCC data sets. Using PDZK1 overexpression and knockdown models in ccRCC cell lines, we demonstrated that PDZK1 inhibited cell proliferation, cell cycle G1/S phase transition, cell migration and invasion, indicating a tumor-suppressor role in the development and progression of ccRCC. Our study further demonstrated that PDZK1 inhibited cell proliferation and migration of ccRCC via targeting SHP-1. PDZK1 was further identified to suppress cell proliferation by blocking SHP-1 phosphorylation at Tyr536 via inhibition of the association between SHP-1 and PLCβ3, and then retarding Akt phosphorylation and promoting STAT5 phosphorylation in ccRCC cells. Moreover, the inhibitive effects of PDZK1 on SHP-1 phosphorylation and the tumor growth were verified in vivoby xenograft tumor studies. Accordingly, PDZK1 expression was negatively correlated with SHP-1 activation and phosphorylation, advanced pathologic stage, tumor weight and size, and prognosis of ccRCC patients. These findings have provided first lines of evidences that PDZK1 expression is negatively correlated with SHP-1 activation and poor clinical outcomes in ccRCC. PDZK1 was identified as a novel tumor suppressor in ccRCC by negating SHP-1 activity.

The object of this study was to explore the effects of basicity (CaO/SiO2ratio), MgO and Al2O3on viscosity and melting temperature of molten slag in the process of coal gasification with blast furnace (BF) slag as heat carrier to recover the waste heat. The results showed that the viscosity and melting temperature of BF slag decreased first and then increased with CaO/SiO2ratio increasing, and the suitable CaO/SiO2ratio was 1.10–1.20. Both viscosity and melting temperature increased with the increasing of MgO and Al2O3in the slag, which should be lower than 8.22 and 11.00%, respectively. What is more, the viscosity estimation model for molten BF slag was established according to the Urbain model and experimental data of slag viscosity. In the model, the activation energy was calculated using slag compositions based on the redefine of material types in the slag, and the temperature was described by the Weymann–Frenkel equation. The viscosity of BF slag system estimated by proposed viscosity estimation model (modified Urbain model) fitted well with the experimental data and the mean deviation was about 17.98%.

As a significant tumor feature, hypoxia can trigger cancer adaptive processes, induce malignant phenotype development, and promote drug resistance. Previous studies demonstrated that exosomes are critical during these procedures. Exosomes are small vesicles formed in vesicular bodies in the endosomal network. These small vesicles are mainly involved in the transport of bioactive molecules between cells. Exosomes are also involved in the mediation of some cellular communications depending on derived donor cells; thus, recipient cells undergo phenotypic changes. Furthermore, hypoxia can remarkably stimulate exosomal secretion; for instance, nucleic acids and proteins as transmission signals in exosomes in a tumor microenvironment are involved in various functions, such as inducing intratumoral heterogeneity, altering immunological responses, producing cancer-associated fibroblasts, and promoting angiogenesis and metastasis. Moreover, exosome contents resemble those of a donor cell; this finding indicates that exosomes may also be regarded as suitable biomarkers of hypoxia status. Therefore, exosomes can be used to facilitate diagnosis and prognosis with minimal invasive procedures. Further studies on exosomes in cancer may provide new therapeutic strategies.

Diploid natural gynogenetic goldfish (2nGRCG), triploid hybrids (3nRB) and tetraploid hybrids (4nRB) are generated by distant hybridization of red common goldfish (RCG, Carassius auratus red var.) and blunt snout bream (BSB, Megalobrama amblycephala). In the present study, we obtained the complete mitochondrial DNA (mtDNA) sequences of the hybrid offspring and compared them with the homologous sequences of RCG and BSB. All mtDNA sequences of these hybrids were 16,580bp in length, and the genes number, size, and order were quite similar to that of RCG. Genetic analysis revealed that the mtDNA sequences of these hybrids had high similarity (>99%) and low divergence (<2%) to their maternal RCG, yet lower similarities (84%) and higher divergences (16%) to their paternal BSB. The phylogenetic analysis also showed that the sequences of 2nGRCG, 3nRB and 4nRB were clustered with RCG rather than with BSB. These results indicate that the mitochondrial genomes of 2nGRCG, 3nRB and 4nRB remain maternally inherited after hybridization and polyploidization. Moreover, clade separation of hybrid offspring from their paternal BSB in the phylogenetic tree implies that phylogenetic analysis of mtDNA is incomplete for elucidating the true relationships between different species, particularly when they have undergone hybridization or allopolyploidization. Our study provides significant information for both evolution and genetic studies of mtDNA for hybrid species and allopolyploidization species.

This paper treats the crack-microcrack interactions in an anisotropic piezoelectric solid. Based on the Green's function approach and the principle of superposition, a system of singular integral equations for the unknown temperature discontinuity and elastic displacement-electric potential (EDEP) defined on each crack face is developed and solved numerically. In the analysis, the residual heat flux, stress and electric displacement (SED) on microcrack location to be released are evaluated directly from the near-tip fields of main crack. Numerical results for SED intensity factors in a three-crack system are presented to illustrate the application of the proposed formulation.

Due to that the high charge density and small radius render In3+cation a stronger Lewis acidity, multifunctional nanoporous In-MOFs have become one of the most promising catalysts for their high activity. Herein, the solvothermal self-assembly by employing 2,4,6-tri (2,4-dicarboxyphenyl)pyridine (H6TDP) as organic linker leads to a robust honeycomb skeleton of {[(CH3)2NH2][InIIIPbII(TDP) (H2O)]⋅3DMF⋅3H2O}n(NUC-52) with the merits of nanoscopic channels, high porosity (61.3%), large specific surface area, and thermal stability. To the best of our knowledge, this is the first 4p-5p heterometallic {InIIIPbII} cluster-based nano-porous host framework, whose activated state possesses the coexistence of Lewis acid-base sites including 7-coordinated Pb2+ions, 4-coordinated In3+ions, uncoordinated carboxyl oxygen atoms, and Npyridineatoms. Performed catalytic experiments exhibited that activated NUC-52owned the high catalytic activity on the cycloaddition reactions of styrene oxide with CO2under mild conditions with excellent turnover number (2475) and turnover frequency (619 h−1). Moreover, activated NUC-52could greatly accelerate the deacetalization-Knoevenagel condensation reactions of benzaldehyde dimethyl acetal and malononitrile. Hence, this work lays down the groundwork for constructing heterometallic cluster-based nanoporous MOFs with excellent Lewis acidic catalysis and chemical stability, which should be ascribed to the reasonable coordination arrangement between organic ligands and distinct metal ions according to the hard–soft acid–base (HSAB) theory.

ABSTRACTIn this paper, a new algorithm is developed based on the homogenization method integrating with the newly developed Hybrid Treffe FEM (HT-FEM) and Hybrid Fundamental Solution based FEM (HFS-FEM). The algorithm can be used to evaluate effective elastic properties of heterogeneous composites. The representative volume element (RVE) of fiber reinforced composites with periodic boundary conditions is introduced and used in our numerical analysis. The proposed algorithm is assessed through two numerical examples with different mesh density and element geometry and used to investigate the effect of fiber volume fraction, fiber shape and configuration on the effective properties of composites. It is found that the proposed algorithm is insensitive to element geometry and mesh density compared with the traditional FEM (e.g.ABAQUS). The numerical results indicate that the HT-FEM and HFS-FEM are promising in micromechanical modeling of heterogeneous materials containing inclusions of various shapes and distributions. They are potential to be used for future application in multiscale simulation.

Primary analyses of cohort 1a of the REFINE trial showed that addition of navitoclax to ruxolitinib induced a 35% or greater reduction in spleen volume (SVR35) and reduced symptoms in patients with myelofibrosis no longer benefiting from ruxolitinib. Here, we report the exploratory post-hoc biomarker analyses from cohort 1a.

Fungal colonies initially extend exponentially and reach a constant linear extension rate determined solely by their growth in the peripheral zone. However the radial extension rates of Sclerotinia sclerotiorumand S. minoraccelerate over time on PDA. Experiments were conducted to analyze the variable extension rates of the two Sclerotiniaspecies and compare them with those of Verticillium dahliaeand Cladosporiumsp. In addition, the effects of starter disk size, disk position in the parent colony, the age of the parent colony, the concentration of potato dextrose broth and of incubation temperature also were determined. While the growth of Cladosporiumsp. and V. dahliaefollowed established linear trends, the radial extension of S. sclerotiorumand S. minorcolonies continuously accelerated over time until they reached the edge of the (150 mm diam) Petri dish. A polynomial model fitted the radial extension of colonies of Sclerotiniaspp. Furthermore the accelerating colony extension rate was partly due to increasing colony radius. The rates of extension from mycelial disks transferred from the parental colony were positively correlated with the radius of the mycelial disks transferred. The rates of extension also were dependent on where the transferred disks were taken from parent colonies and the age and radius of the parent colony. On potato dextrose agar medium the extension rates of colonies of S. sclerotiorumand S. minoralso were affected by broth concentration and temperature. With increasing nutrient concentration colony extension rates increased and were highest at 25 C. This study revealed a novel pattern of radial growth for Sclerotiniaspp. that diverged from the established growth patterns of fungal colonies. Knowledge of the differences in growth behavior may be exploited in the laboratory studies on fungal competition and hyperparasitism and potentially in disease control strategies.

Synchronized maturation of ascospores of Sclerotinia sclerotiorumis desirable for establishing a transformation system, conducting genetic analyses of the pathogen, defining the precise epidemiological roles of ascospores and screening plant germplasm for resistance. In general, fresh apothecia collected from germinated sclerotia contained primarily immature or discharged asci. This study was undertaken to investigate whether maturation of asci and ascospores could be enhanced by incubation of excised apothecia and to determine the effects of factors such as temperature, excision time, light and ventilation on maturation of asci and ascospores in excised apothecia. Maturation of asci was compared between intact and excised apothecia that were incubated under similar conditions. Results demonstrated that temperature was an important factor affecting ascus maturation of S. sclerotiorumduring incubation of excised apothecia, and the optimum temperature was around 21 C. After incubation at 21 C for 30 h, the percentage of undischarged mature asci in excised apothecia increased up to 70–80%. This increase was accompanied by a significant increase in ascospore production of up to 5 × 105ascospores per apothecium. Detailed time course studies indicated that mature asci peaked at 30–36 h of postexcision incubation. Mature asci and the number of ascospores were higher in open incubation than in closed incubation, suggesting that accumulation of volatile substances was not required for ascus/ascospore maturation during postexcision incubation and ventilation could enhance the maturation process. Light also did not affect the maturation of asci during the incubation of excised apothecia. Germination rates for ascospores from excised apothecia under various treatments were similar to those from untreated apothecia but declined slightly with time postexcision. The incubation of excised apothecia promoted ascus maturation compared with intact apothecia.

Summary A new meshless method is developed to analyze steady-state heat conduction problems with arbitrarily spatially varying thermal conductivity in isotropic and anisotropic materials. The analog equation is used to construct equivalent equations to the original differential equation so that a simpler fundamental solution of the Laplacian operator can be employed to take the place of the fundamental solutions related to the original governing equation. Next, the particular solution is approximated by using radial basis functions, and the corresponding homogeneous solution is solved by means of the virtual boundary collocation method. As a result, a new method fully independent of mesh is developed. Finally, several numerical examples are implemented to demonstrate the efficiency and accuracy of the proposed method. The numerical results show good agreement with the actual results.

Water in Fischer−Tropsch synthesis (FTS) on supported cobalt catalysts is known to deactivate the catalysts. The deactivation involves the reoxidation of highly dispersed cobalt phase by water and water-induced sintering. In both cases, the dispersion state of the cobalt phase in the supported catalyst plays an important role. Therefore, the deactivation kinetics depends on the surface structure of the catalyst. Mathematical models are formulated to describe the deactivation behavior of cobalt catalyst pellets with the dependence on catalyst structure and reaction conditions. On the crystallite scale, a size-dependent deactivation model for individual metal particles is built; on the catalyst scale, the deactivation and growth (shrinking) of each individual metal crystallite in the pellet as well as the radial distribution for temperature and concentrations are accounted for using a population balance equation (PBE) coupled with intraparticle diffusion-reaction equations. The model is used for optimization of catalyst design. Results show that both intrapellet diffusion limitation and the particle size distribution have a significant impact on the catalyst deactivation behavior. The optimal value of particle size in a pellet varies in a wide range (8−15 nm) depending on when the system is shut down and the catalyst is replaced. It is possible to obtain a dramatic performance boost by using the optimal particle size.

Silver−vanadium pentoxide composite films have been fabricated by 355-nm pulsed laser reactive deposition on stainless steel substrates. XRD and SEM analyses showed that the composite films AgxV2O5 (x = 0.1−0.5) deposited at a substrate temperature of 300 °C in the presence of ambient 100 mTorr O2 for 0.5 h were amorphous and became a polycrystalline structure after 2 h of deposition. The valence states of Ag and V for AgxV2O5 composite film were examined by XPS measurement. The amorphous Ag0.5 V2O5 composite film electrode exhibited a specific capacity as high as 396 mA·h/g in the range of 4.0−1.0 V at a 2 C rate and remained at a capacity of 260 mA·h/g at a high rate of 20 C with no obvious fading upon cycling more than 1000 cycles. In addition, the electronic conductivities of AgxV2O5 composite films were 2−3 orders of magnitude higher than that of pure V2O5 film. The dramatically improved rate and cycling performance might be related to the changes in microstructure of the AgxV2O5 composite films.

First- and second-order statistical properties of ultrasonic speckles reflected from a rough interface are studied theoretically and experimentally in this paper. A theoretical model for predicting statistical properties of ultrasonic speckles is constructed, based on the Fresnel-Huygens principle and three basic assumptions. Distributions of the amplitude and phase of ultrasonic speckles in a scattering space are studied; the study shows that they are in the form of Rayleigh and uniform distribution, respectively. Using the proposed model, the average transverse size of the speckles within a scattering domain, which are received by a focus probe, is investigated. The average transverse size is found to be dependent on the characteristics of the measuring system only, and does not vary with the position in the domain. To verify the applicability of the theoretical model, a special experimental set-up was designed. The corresponding experiments were conducted for measuring the sound pressure of the ultrasonic speckles reflected from a rough interface between water and aluminium alloy. The numerical results are compared with the experimental ones. The comparison demonstrates that the theoretical model and the three related assumptions are suitable for analysing statistical properties of ultrasonic speckles reflected from a rough interface.

Chromium dioxide dihydrogen and bis-dihydrogen complexes:  (η²-H2)CrO2 and (η²-H2)2CrO2 have been prepared by co-condensation of the CrO2 molecules generated from laser ablation of CrO3 with H2 in excess argon at 11 K. Broad-band photolysis of the (η²-H2)CrO2 complex induced a photoisomerization to produce the HCrO(OH) molecule. In addition, laser-ablated Cr atoms reacted with H2/O2 mixtures to give primarily the CrO2 and (η²-O2)CrO2 molecules, while the (η²-H2)CrO2, (η²-H2)2CrO2 and HCrO(OH) molecules were also produced on annealing and photolysis. The aforementioned species were unambiguously characterized by FTIR spectroscopy and density functional theoretical calculations.

This paper presents the results of research work on modal identification of Tsing Ma bridge ambient testing data by using an improved eigensystem realization algorithm. The testing was carried out before the bridge was open to traffic and after the completion of surfacing. Without traffic load, ambient excitations were much less intensive, and the bridge responses to such ambient excitation were also less intensive. Consequently, the bridge responses were significantly influenced by the random movement of heavy construction vehicles on the deck. To cut off noises in the testing data and make the ambient signals more stationary, the Chebyshev digital filter was used instead of the digital filter with a Hanning window. Random decrement (RD) functions were built to convert the ambient responses to free vibrations. An improved eigensystem realization algorithm was employed to improve the accuracy and the efficiency of modal identification. It uses cross-correlation functions ofRD functions to form the Hankel matrix instead of RD functions themselves and uses eigenvalue decomposition instead of singular value decomposition. The data for response accelerations were acquired group by group because of limited number of high-quality accelerometers and channels of data loggers available. The modes were identified group by group and then assembled by using response accelerations acquired at reference points to form modes of the complete bridge. Seventy-nine modes of the Tsing Ma bridge were identified, including five complex modes formed in accordance with unevenly distributed damping in the bridge. The identified modes in time domain were then compared with those identified in frequency domain and finite element analytical results.

Matrix isolation infrared spectra and quantum chemical calculations of the (NN)xCrO and (NN)xCrO2 (x = 1, 2) molecules are reported. These species were prepared and isolated in solid argon by three different methods:  co-condensation of the CrO and CrO2 molecules generated from laser ablation of CrO3 with N2/Ar; reactions of laser-ablated Cr atoms with O2/N2/Ar mixtures, and reactions of laser-ablated Cr atoms with N2O/Ar. The product absorptions were identified by isotopic substitutions and density functional theoretical calculations. Evidence is also presented for the (NN)(O2)CrO2 molecule.

The study of the reactions of transition metal atoms with water is continued in this work. Here we report the study of the reactions of Fe with H2O and FeO with H2. In agreement with previous thermal atom experiments, laser-ablated Fe atoms reacted with H2O to form the FeOH2 and HFeOH molecules as characterized by matrix isolation FTIR spectroscopy. On photolysis, the Fe atoms could further insert into the OH bonds in H2O molecules with a stepwise pattern to form multi metal−oxo core species including HFeOFeH, HFeOFeOH, and possibly HFeOFeOFeH, which were identified by isotopic substitutions and density functional calculations. Reactions of FeO with H2 also lead to HFeOH as the primary product. In addition, a potential energy surface for the Fe + H2O  FeO + H2 reaction was constructed to elucidate the reaction mechanisms.

The reactions of Mn atoms with water and MnO with H2 have been studied using matrix-isolation FTIR and DFT theoretical calculations. In solid argon, Mn atom reacted with H2O molecule to form the MnOH2 complex spontaneously. Photolysis destroyed the MnOH2 complex and produced the inserted HMnOH molecule. In addition, HMnOMnH, Mn(OH)2, HMnOMnOH, and posssibly HMnOMnOMnH molecules were also produced on photolysis. Reaction of MnO with H2 gave the (H2)MnO complex without activation energy. Photolysis of the (H2)MnO produced the inserted HMnOH molecule as well. The aforementioned species were identified via isotopic substitutions as well as density functional theoretical frequency calculations. Potential energy surface for the Mn + H2O  MnO + H2 reaction was also given. Our calculation results showed that all these reaction intermediates and products are high spin molecules. The MnOH2, HMnOH and (H2)MnO molecules have ground states with S = ⁵/2, the HMnOMnH, and HMnOMnOH molecules have ground states with S = ¹⁰/2, and the HMnOMnOMnH molecule has ground state with S = ¹⁵/2.

The nickel, copper, and silver metal carbonyl chloride molecules have been prepared and isolated in solid argon by cocondensation of the species generated from 1064 nm laser ablation of metal chlorides with carbon monoxide in excess argon at 11 K. On the basis of isotopic substitution experiments and density functional theory frequency calculations, infrared absorptions at 2118.7, 2156.8, and 2184.0 cm^-1 are assigned to the C−O stretching vibrations of the Ni(CO)Cl, Cu(CO)Cl, and Ag(CO)Cl molecules. Density functional calculations predicted that the M(CO)Cl (M = Ni, Cu, Ag) molecules are linear; the binding energies with respect to MCl + CO were estimated to be 37.7, 34.2, and 17.8 kcal/mol, respectively. In addition, evidence is also presented for the M(CO)Cl2, M(CO)2Cl, and M(CO)2Cl2 (M = Ni, Cu) molecules.

The triplet and singlet potential energy surfaces (PES) for O(³P,¹D) + CF3Br reactions have been studied using the density functional method at the B3LYP level. Geometries, energies, and vibrational frequencies of CF3Br, CF3BrO (¹A‘ and ³A‘ ‘), CF3OBr (¹A‘), CF3, BrO, CF2O, BrF, and CF2O−BrF complexes have been examined. Transition states connecting these species have been characterized and the whole potential surfaces could satisfactorily describe the O + CF3Br reactions. In the gas phase, the OBr radical is the main product on both the singlet and triplet PESs. In a condensed matrix, however, CF3OBr should be the dominant product generating from the recombination of nascent CF3 + OBr.

The ClCuOCO and BrCuOCO molecules have been observed by cocondensation of the species generated from 1064 nm laser ablation of CuCl2 and CuBr2 targets with CO2/Ar mixtures. With the aid of density functional calculations and isotopic substituted experiments, infrared absorptions at 2383.9 and 2381.4 cm^-1 are assigned to the antisymmetric CO2 stretching vibrations of the ClCuOCO and BrCuOCO molecules in solid argon, respectively. Theoretical calculations predicted these molecules to be linear with a ¹Σ⁺ ground state. The interaction between CuX and CO2 is mainly electrostatic and thus induces a blue shift of the CO2 antisymmetric stretching vibration. The binding energies for ClCuOCO and BrCuOCO with respect to those for CuX and CO2 were calculated to be 12.5 and 11.4 kcal/mol, respectively. Similar experiments with AgCl and AgBr gave the analogous ClAgOCO and BrAgOCO. The binding energies were estimated to be 6.5 and 5.9 kcal/mol for ClAgOCO and BrAgOCO, respectively.

The ClCuNN, BrCuNN, and ClNiNN molecules have been prepared and isolated in solid argon by co-condensation of the species generated from 1064 nm laser ablation of copper or nickel halides with N2/Ar gas mixtures. On the basis of isotopic substituted experiments and density functional theory calculations, infrared absorptions at 2296.3, 2297.8, and 2246.3 cm^-1 are assigned to the N−N stretching vibrations of the linear molecules, ClCuNN, BrCuNN, and ClNiNN in solid argon, respectively. The binding energies for ClCuNN, BrCuNN, and ClNiNN with respect to MX (M=Cu, Ni, X=Cl, Br) and N2 were computationally estimated to be 20.4, 18.7, and 18.9 kcal/mol, respectively.

Reactions of laser-ablated Nb atoms with CO2 give insertion products ONbCO and O2Nb(CO)2 and the negative species O2Nb(CO)2^-, which have been identified by matrix isolation FTIR method and DFT calculations. Two ONbCO structural products (I and II) were observed with infrared absorptions at 1902.6/960.1 and 1821.3/915.6 cm^-1, respectively. UV light irradiation destroyed the O2Nb(CO)2^- anion completely, while the intensities of ONbCO(II) and O2NbCO were enhanced markedly. Sample annealing led to the obvious increase of ONbCO(II), while the ONbCO(I) can further combine with CO2 to form O2Nb(CO)2.

Lithium ion diffusion processes in pulsed laser-deposited TiO2 film electrodes are investigated by electrochemical and isothermal transient ionic current (ITIC) methods. Cyclic voltammogram and potential step measurements are used to examine the processes of insertion of Li ions into the TiO2 electrode. Two diffusion processes of Li ion, driven by the concentration gradient and by an applied field, are demonstrated by ITIC analysis. The diffusion constants are dependent on the measuring method and the diffusion mechanism. These results clarify the diffusion behavior of Li ion in anatase TiO2 film and prove that pulsed laser deposition is a promising method for producing TiO2 film electrodes.

An unusual intercalation of lithium zinc oxide (LiZnO) is produced by the electrochemical lithium insertion into a ZnO film electrode. As its isolated unit, LiOZn and LiOZn⁺ molecules exhibit a new type of hypervalent species with two heterometal atoms and one oxygen atom. Time-of-flight mass spectrometry has also been employed to give direct experimental evidence for the existence of LiOZn⁺ generated by laser ablation of a composite Li/ZnO target in a high vacuum. The stability and structure of the hypervalent molecule LiOZn and its ion as well as its isomer are investigated by ab initio molecular orbital calculations. The overlap between the 2s orbital in Li, the 2py orbital in O, and the 4s orbital in Zn should be responsible for a linear structure of these molecules. The extra one electron beyond the usual octet in LiOZn may play an important role in the binding between a lithium atom and a zinc atom around the central oxygen atom.

Using matrix-isolation infrared spectroscopy and DFT calculations, the reactions between 532 nm pulsed laser-ablated Ta and CO2 in argon gas ambient have been investigated. The major reaction products trapped in solid argon were found to be neutral OTaCO and O2Ta(CO)2 the anions OTaCO^- and O2Ta(CO)2^-. The observed absorption bands of the reaction products were identified by isotopic substitution and reproduced well by DFT calculations of vibrational fundamentals. Upon irradiation with a pulsed laser at 355 nm, the neutral OTaCO and O2Ta(CO)2 were enhanced while O2Ta(CO)2^- and C2O4^- anions disappeared in the measured IR spectra. The potential energy surfaces of the interactions of Ta with CO2 and CO2^- were calculated, and the insertion of Ta into CO2 was suggested to proceed via electron transfer from Ta to CO2, in which CO2^- formation plays an important role in the activation of inert CO2 molecules.