Development and uniqueness test of highly selective atomic topological indices based on the number of attached hydrogen atoms.

On the basis of the atomic graph-theoretical index - aEAID (atomic Extended Adjacency matrix IDentification) and molecular adjacent topological index - ATID (Adjacent Topological IDentification) suggested by one of the authors (Zhang Q), a highly selective atomic topological index - aATID (atomic Adjacent Topological IDentification) index was suggested to identify the equivalent atoms in this study. The aATID index of an atom was derived from the number of the attached hydrogen atoms of the atom but omitting bond types. In this case, the suggested index can be used to identify equivalent atoms in chemistry but perhaps not equivalent in the molecular graph.

Study on Mechanical Properties of Polyurethane Cross-Linked P(E-co-T)/PEG Blended Polyether Elastomer.

To improve the mechanical properties of polyurethane cross-linked poly (ethylene oxide-co-tetrahydrofuran) (P(E-co-T)) elastomers at room temperature, using poly (ethylene oxide-co-tetrahydrofuran) and high-molecular-weight polyethylene glycol (PEG) as raw materials and polyisocyanate N100 as curing agent, a series of polyurethane cross-linked blended polyether elastomers were prepared by changing the elastomer-curing parameter R value (n(-NCO)/n(-OH)) and P(E-co-T)/PEG ratio. Equilibrium swelling measurements showed that the chemical cross-linkage of the elastomers tended to decrease with the decreasing R value, the average molecular weight (Mc) of the network chain increased, and the density of the network chain (N0) decreased. Wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC) tests showed that PEG chain segments within the elastomers crystallized at room temperature, while the crystallinity increased with decreasing R value and increasing PEG content.

Bioinspired Supramolecular Nanotoroids with Aggregation-Induced Emission Characteristics.

Supramolecular toroids have attracted continuous attention because of their fascinating topological structure and important role in biological systems. However, it still remains a great challenge to construct supramolecular functional toroids and clarify the formation mechanism. Herein, we develop a strategy to prepare supramolecular helical fluorescent nanotoroids by cooperative self-assembly of an amino acid and a dendritic amphiphile (AIE-den-1) with aggregation-induced emission characteristics.

Synthesis of two novel neutral polymeric bonding agents to enhance the mechanical properties of composite solid propellants.

Currently, only a few bonding agents can be utilized efficiently in nitramine filler material-based solid rocket energetic binder systems. Herein, we demonstrate the synthesis and specific characterization of two kinds of neutral polymeric bonding agents (NPBA-1 and NPBA-2) and their application in composite propellants consisting of the nitramine octogen (HMX) and glycidyl azide polymer (GAP). The as-obtained NPBAs were well-coated on the surface of HMX and RDX due to their functionalized groups, and they significantly affected the viscosity of the uncured propellant mixtures and possessed obviously enhanced mechanical properties in the cured AP/HMX/GAP propellant mixtures, even at low concentrations (down to 0.

Facile Solution Process of VO Film with Mesh Morphology for Enhanced Thermochromic Performance.

The fabrication and applications of VO film continue to be of considerable interest due to their good thermochromic performance for smart windows. However, low visible transmittance () and solar modulation efficiency (∆) impede the application of VO film, and they are difficult to improve simultaneously. Here, a facile zinc solution process was employed to control the surface structure of dense VO film and the processed VO film showed enhanced visible transmittance and solar modulation efficiency, which were increased by 7.

Acid Solution Processed VO-Based Composite Films with Enhanced Thermochromic Properties for Smart Windows.

As a typical thermochromic material, VO coatings can be applied to smart windows by modulating the transmission of near infrared (NIR) light via phase transition. However, the inherent undesirable luminous transmittance () and solar modulation efficiency (Δ) of pure VO impede its practical application. In order to solve this problem, the porous VO based composite film was prepared by magnetron sputtering and subsequent acid solution process with ZnVO particles used as a sacrificial template to create pores, which showed excellent (72.

Novel saprobic species (Hermatomycetaceae, Pleosporales) from China (Yunnan Province) and Thailand.

During our survey of the diversity of woody litter fungi in China and Thailand, three species were collected from dead woody twigs of sp. (Dipterocarpaceae) and (Boraginaceae). Both morphology and multigene analyses revealed two taxa as new species ( and ) and the remaining collections as new records of .

Synthesis and Stability of Hydrogen Storage Material Aluminum Hydride.

Aluminum hydride (AlH) is a binary metal hydride with a mass hydrogen density of more than 10% and bulk hydrogen density of 148 kg H2/m3. Pure aluminum hydride can easily release hydrogen when heated. Due to the high hydrogen density and low decomposition temperature, aluminum hydride has become one of the most promising hydrogen storage media for wide applications, including fuel cell, reducing agents, and rocket fuel additive.

Green preparation of high-quality and low-cost graphene from discarded polyethylene plastic bags.

A facile method was used to prepare graphene from discarded polyethylene plastic bags in our work. In order to make high-quality graphene, PE plastic bags were ultrasonically cleaned, ball milled and microwave sintered successively. The height of the 2D band was 1.

Deletion of P110δ promotes the development of myocarditis in ApoE‑deficient mice by increasing mononuclear cell peritoneal infiltration.

Phosphoinositide 3-kinase catalytic subunit δ isoform (P110δ) is mainly expressed in white blood cells. It is involved in T and B lymphocyte differentiation, maturation and the neutrophil chemotaxis process. Apolipoprotein E (ApoE) is an arginine‑rich alkaline protein, which is present in plasma chylomicron, low‑density lipoprotein and very low‑density lipoprotein.

Revealing the Charge Storage Mechanism of Nickel Oxide Electrochromic Supercapacitors.

Nickel oxide (NiO) is considered one of the most promising positive anode materials for electrochromic supercapacitors. Nevertheless, a detailed mechanism of the electrochromic and energy storage process has yet to be unraveled. In this research, the charge storage mechanism of a NiO electrochromic electrode was investigated by combining the in-depth experimental and theoretical analyses.

A One-Step Approach to -(Hetero)aryl-3,5-dinitropyrazoles from (Hetero)aryl Amines.

Potassium 1,1,3,3-tetranitropropane-1,3-diide (KTNP) was found to react readily with various (hetero)aryl amines (12 examples) to give corresponding -(hetero)aryl-3,5-dinitropyrazoles in moderate to excellent yields. The reactions were performed at mild temperature, and most of the reactions completed in less than 4 h. Four potential energetic compounds show high enthalpy of formation, excellent thermal stability, and good sensitivity, with 3-(3,5-dinitropyrazol-1-yl)-1-1,2,4-triazole () being a potential 2,2',4,4',6,6'-hexanitrostibene (HNS) replacement.

Theoretical study on the gas-phase reaction mechanism of ammonia with nitrous oxide.

Applications of nitrous oxide (NO) as an oxidant in green propellants and propulsion systems have attracted a lot of attention. In this study, the reaction pathways for the oxidation of ammonia (NH) with NO were studied using the B3LYP/6-31++G** method of density functional theory (DFT). The results reveal that the reaction between NO and NH proceeds through a chain reaction mechanism.

A facile fabrication of porous fluoro-polymer with excellent mechanical properties based on high internal phase emulsion templating using PLA as co-stabilizer.

The stability of fluoro-high internal phase emulsion (fluoro-HIPE) systems and fluoro-polyHIPEs' mechanical strength require further improvement to meet the requirements of future applications. In this study, we used polylactic acid (PLA) as a co-stabilizer to improve the stability of the fluoro-polyHIPE. The effects of concentration and molecular weight of PLA on the pores of the fluoro-polyHIPEs were investigated.

Study on the anisotropic response of condensed-phase RDX under repeated stress wave loading via ReaxFF molecular dynamics simulation.

Anisotropic mechanical response and chemical reaction process of cyclotrimethylene trinitramine (RDX) along crystal orientations were studied with molecular dynamics simulations using ReaxFF potential under repeated stress wave loading. In the simulations, shocks were propagated along the [010], [001], [210], [100], [111], and [102] orientations of crystal RDX at initial particle velocity Up in the range of 1∼4 km/s. For shocks at Up ≤ 2 km/s, local stacking fault and molecular conformational change can only cause marginal temperature and pressure increase without molecular decomposition.

Facile synthesis of diverse graphene nanomeshes based on simultaneous regulation of pore size and surface structure.

Recently, graphene nanomesh (GNM) has attracted great attentions due to its unique porous structure, abundant active sites, finite band gap and possesses potential applications in the fields of electronics, gas sensor/storage, catalysis, etc. Therefore, diverse GNMs with different physical and chemical properties are required urgently to meet different applications. Herein we demonstrate a facile synthetic method based on the famous Fenton reaction to prepare GNM, by using economically fabricated graphene oxide (GO) as a starting material.

Facile synthesis and photoluminescence characteristics of blue-emitting nitrogen-doped graphene quantum dots.

A one-step hydrothermal method for synthesizing nitrogen-doped graphene quantum dots (N-GQDs) from organic carbon sources is presented in this paper. The high-quality N-GQDs can be obtained via tuning the degree of dehydration/carbonization of citric acid and doping of nitrogen atoms into the graphene lattice. The micromorphology, chemical structure, composition and photoluminescence (PL) characteristics of the N-GQDs were characterized systematically.

A Sheet-like Carbon Matrix Hosted Sulfur as Cathode for High-performance Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are a promising candidate of next generation energy storage systems owing to its high theoretical capacity and energy density. However, to date, its commercial application was hindered by the inherent problems of sulfur cathode. Additionally, with the rapid decline of non-renewable resources and active appeal of green chemistry, the intensive research of new electrode materials was conducted worldwide.

A DFT study of the unimolecular decomposition of 1,2,4-butanetriol trinitrate.

To improve understanding of the unimolecular decomposition mechanism of 1,2,4-butanetriol trinitrate (BTTN) in the gas phase, density functional theory calculations were performed to determine various decomposition pathways at the B3LYP/6-311G** level. Two main mechanisms for the unimolecular decomposition of BTTN were found. In the first, homolysis of one of the O-NO2 bonds occurs to form •NO2 and CH2ONO2CHONO2CH2CH2O•, which subsequently decomposes to form CH3CHO + •CHO + 3NO2 + HCHO.

Molecular dynamics of neutral polymer bonding agent (NPBA) as revealed by solid-state NMR spectroscopy.

Neutral polymer bonding agent (NPBA) is one of the most promising polymeric materials, widely used in nitrate ester plasticized polyether (NEPE) propellant as bonding agent. The structure and dynamics of NPBA under different conditions of temperatures and sample processing are comprehensively investigated by solid state NMR (SSNMR). The results indicate that both the main chain and side chain of NPBA are quite rigid below its glass transition temperature (Tg).

Theoretical studies on the unimolecular decomposition of nitroglycerin.

To improve the understanding of the unimolecular decomposition mechanism of nitroglycerin (NG) in the gas phase, density functional theory calculations were performed to determine various decomposition channels at the B3LYP/6-311G** level. For the unimolecular decomposition mechanism of NG, we find two main mechanisms: (I) homolytic cleavage of O-NO2 to form •NO2 and CH2ONO2CHONO2CH2O•, which subsequently decomposes to form •CHO, •NO2, and 2CH2O; (II) successive HONO eliminations to form HONO and CHO-CO-CHO, which subsequently decomposes to form CH2O + 2CO2 and •CHO + CO. We also find that the former channel has slightly smaller activation energy than the latter one.