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Integrating noble metals with semiconductors is a viable approach to enhancing the photoelectric conversion efficiency of samples. The combination of metals with semiconductors has found widespread application in the field of optoelectronics and devices. Herein, metal (M = Ag/Cu) and MoS2 (MoS2/M) nanocomposites were successfully synthesized using magnetron sputtering and hydrothermal two-step methods. The sizes and morphologies of the metals can be adjusted by controlling the sputtering time. Metals Ag and Cu were anchored onto defective MoS2 nanomaterials, serving as photoanodes and light absorbers, respectively. The vacancy-induced defect structure, along with the synergistic effect of the interface and size, can simultaneously regulate the charge-carrier dynamics and the band structure of MoS2/M nanocomposites. The transient photocurrent responses and the electrochemical impedance spectroscopy results demonstrate the excellent photoelectrochemical (PEC) properties of the MoS2/M nanocomposites. A finite-difference time-domain simulation reveals that the strong plasmonic electromagnetic field generated by metal can significantly enhance the energy-band transition rate of neighboring materials and improve photogenerated carrier separation. Compared with pure MoS2, MoS2/M nanocomposites exhibit enhanced nonlinear-optical (NLO) behavior. This improvement stems from an effective charge separation, which is facilitated by a synergistic interaction between the electric field and the plasmonic magnetic field. Density functional theory calculations indicate a decrease in the energy of the Mo d orbital, which contributes to the acceptance of d electrons from Ag/Cu. The exceptional performance of MoS2/M nanocomposites is primarily attributed to the occupancy of Mo d orbitals, driven by the intense interaction among MoS2 and Ag/Cu optimal combination. This work offers valuable insights into the design of heterojunctions with abundant surface/interface contact and defect features to enhance tunable electron-transfer kinetics. Such advancements pave the way for achieving a high NLO conversion efficiency and the development of efficient PEC anode materials. [ABSTRACT FROM AUTHOR]

Semiconducting 2D layered transition metal dichalcogenides (TMDs) and TMD heterostructures have attracted much attention in porous materials because of their unique electrical and optical properties. However, the role of controlled epitaxial growth and strain in the interfacial electron transfer and nonlinear optical (NLO) conversion efficiency of the TMD/TMD nanoheterostructure remains poorly understood. Herein, we have successfully synthesized a MoS2/MoTe2 nanoheterostructure with excellent photoelectric and NLO properties. The designed MoS2/MoTe2 nanoheterostructure exhibits excellent NLO performance, including a high nonlinear absorption (NLA) coefficient of 10–7 cm/W at the pulse energy of 5 μJ, which is attributed to the enhanced light absorption capacity of MoTe2 and the modulation of interlayer carrier diffusion. Based on the synergistic effects of optimization strain and interface engineering, an in-depth analysis was conducted on the effects of surface modification on the photoelectrochemical (PEC) performance optimization of the MoS2/MoTe2 nanoheterostructure. The synergistic effect of strain and the interface can promote the continuous transfer of electrons between MoTe2 and MoS2. This work studied the visualization control interface and interlayer electron/exciton phonon coupling in van der Waals MoS2/MoTe2, providing some inspiration for achieving good NLO conversion efficiency and efficient PEC anode materials. [ABSTRACT FROM AUTHOR]

Electronic structures of metal and semiconductor composites play a crucial role in photoelectric conversion. To obtain a fast-response photoelectrochemical (PEC) anode, its orbital regulation is a challenge. Herein, the occupancy state of the d orbitals of Mo is adjusted to achieve high-efficiency photoelectric conversion by adjusting the quantity of Cu by magnetron sputtering deposited in Cu/MoS2 composites. Characterization results indicate that the SEM morphology of MoS2 changes distinctly. Meanwhile, the (111) and (200) diffraction peaks and 0 and 2+ valence states of Cu appeared in XRD and XPS, respectively, confirming the successful synthesis of Cu/MoS2. The prior band shift at the heterojunction causes efficient separation of photogenerated charge carriers and the shift of the position of Mo 3d to higher binding energies, which results in weaker intrinsic luminescence at 810 nm in the PL spectrum and smaller charge transfer resistance in the electrochemical impedance spectroscopy spectra, confirming the high PEC performance of the Cu/MoS2 composites. Meanwhile, the density functional theory calculations reveal that the energy of the d orbital of Mo in MoS2 decreases, which is helpful to accept electrons in Cu 3d. The Mo d track-occupancy introduced through the strong interplay between the most desirable combination of MoS2 and Cu will be accountable for such record-high performance. Therefore, this study makes a strong case for fine-tuning the electronic structures of PEC anode materials. [ABSTRACT FROM AUTHOR]

A magnetic beads based immunoaffinity capillary electrophoresis method for total Immunoglobulin E quantification in serum has been developed. The method combines speed, automation ability, and minimal sample consumption. Only 1 [micro]L of serum is required while the whole immunoaffinity capillary electrophoresis method is performed in less than 50 min. The concomitant use of online immunocapture, transient isotachophoresis, and laser-induced fluorescence detection provides a sensitivity in the low picomolar range and a highly linear fluorescence response over 4 orders of magnitude (IgE concentration ranging from 2.4 to 2400 ng/mL). After validation with a reference material, the method has been successfully applied to the quantification of total IgEs in patient sera. The results compared well with classical ImmunoCap data.

Density functional theory is used for studying the structure and stability of a set of [(CF).sub.60] isomers. The relative energy per CF unit of the most stable isomer to graphite fluoride [(CF).sub.n] is 3.7 kcal/mol, which is smaller than that of [C.sub.60] fullerene per carbon to graphite.

The structure and energy of aluminum nitride cages (AIN) (sub n) (n=2 -41) investigated theoretically is described. The qualitative results obtained were validated on the basis of ab initio and density functional calculations and compared with those of the structural related (BN) (sub n) cages from density functional tight-binding results.

The structure and stability of the (B12N12)n (n = 1, 2) cages are calculated at the B3LYP level of density functional theory. The most stable B24N24 structure deduced from the two B12N12 (Th) cages is found to have an unexpected tube form.

Calmodulin reveals high levels of attraction for melittin, which can be bound by the four subunits of phosphorylase kinase. The reaction between melittin and the catalytic gamma-subunit of the enzyme results in the important inactivation of the phosphorylase kinase holoenzyme. Potential autoregulation of the enzyme depends on the varying distinction of calmodulin-binding peptides. Reaction with the delta-subunit can cause negligible inactivation by melittin.

A synthetic strategy was developed to perform synthesis of porphyrins containing between one and four stereogenic centers, such that their molecular weights vary only as a result of methyl groups which give the chiral forms. The self-assembly and chiral structure of the aggregates of porphyrin molecules are observed to be significantly influenced by the number of stereogenic centers.

A detail study was conducted to study the molecular structures of pyrazine in the 3s Rydberg states and the ground and excited states of its cations. The findings offered insights into the dynamics of ionic states and high-n Rydberg states converging to the [D.sub.1] vibronic states which are short-lived due to electronic autoinization to the [D.sub.0] continuum.

Chiral domains are formed at liquid/solid interface by achiral diarylethenes due to surface-induced atropoisomerism. Molecular dynamics have shown that these dimers of diarylethenes are chiral dimers, rather than prochiral dimers.

A new process combining double-miniemulsion/emulsion polymerization with Sol-gel technology to synthesize monodispersed hydrophilic magnetic nanospheres that exhibit a much higher saturation magnetization due to a large fraction of magnetite is developed. The superparamagnetic properties of nanospheres would allow them to serve as ideal candidates for biomedical applications such as nucleic acid extraction, cancer diagnosis and treatment, biosensors, and drug delivery.

The structures and energies of isolobal (CH)n and (BCO)n polyhedral species are computed at the B3LYP density functional theory level. Unlike the (CH)n cages, the most stable (BCO)n polyhedra (n greater than equal to 10) prefer structures with the largest numbers of three-membered rings.

The vertical ionization potentials and the energy as well as the nucleus independent chemical shift (NICS) at the cage center are computed for the first four most stable isomers. The structure and stability of 27C(sub 48) fullerene is computed at B3LYP.

Research describes the aggregation and dissociation of isolated ryanodine receptors in aqueous medium containing different concentrations of sodium and potassium salts. Results show that the receptors aggregate in low salt concentrations and at a total salt concentration of 0.15 molar, the aggregation and dissociation of the receptor depend on the relative concentration of individual salts.

As a highly toxic and widely used chemical, phosgene has become a serious threat to humankind and public security because of its potential use by terrorists and unexpected release during industrial accidents. For this reason, it is an urgent need to develop facile, fast, and selective detection methods of phosgene. In this Article, we have constructed a highly selective fluorescent sensor o-Pab for phosgene with a BODIPY unit as a fluorophore and o-phenylenediamine as a reactive site. The sensor o-Pab exhibits rapid response (15 s) in both colorimetric and turn-on fluorescence modes, high selectivity for phosgene over nerve agent mimics and various acyl chlorides and a low detection limit (2.7 nM) in solutions. In contrast to most undistinguishable sensors reported, o-Pab can react with phosgene but not with its substitutes, triphosgene and biphosgene. The excellent discrimination of o-Pab has been demonstrated to be due to the difference in highly reactive and bifunctional phosgene relative to its substitutes. Furthermore, a facile testing paper has been fabricated with poly(ethylene oxide) immobilizing o-Pab on a filter paper for real-time selective monitoring of phosgene in gaseous phase. [ABSTRACT FROM AUTHOR]