Analysis of the controlling factors of resistivity fluctuations in tight sandstone reservoirs of the Hangjinqi gas field, Ordos basin.

In the central region of the Lower Shihezi Formation within the Hangjinqi Gas Field, Ordos Basin, China, gas-bearing tight sandstone reservoirs exhibit a coexistence of low-resistivity and medium-to-high-resistivity characteristics. These reservoirs are characterized by significant resistivity fluctuations, posing challenges to the accurate calculation of gas saturation using the classical Archie equation and its derivatives. Consequently, both qualitative and quantitative evaluations of gas-bearing tight sandstone reservoirs are often hindered.

Promoting the Cobalt Phthalocyanine-Catalyzed Electrochemical Reduction of Carbon Dioxide with the Coadsorption of Melamine.

Electrochemical reduction of carbon dioxide (CORR) is a promising strategy for mitigating global warming and producing value-added products simultaneously. Molecular catalysts, such as cobalt phthalocyanine (CoPc), are known to be effective in converting carbon dioxide (CO) to carbon monoxide (CO). However, it is still challenging to improve the reaction rate and selectivity of this conversion.

A Fluorination Strategy and Low-Acidity Anchoring Group in Self-Assembled Molecules for Efficient and Stable Inverted Perovskite Solar Cells.

Herein, we synthesized two donor-acceptor (D-A) type small organic molecules with self-assembly properties, namely MPA-BT-BA and MPA-2FBT-BA, both containing a low acidity anchoring group, benzoic acid. After systematically investigation, it is found that, with the fluorination, the MPA-2FBT-BA demonstrates a lower highest occupied molecular orbital (HOMO) energy level, higher hole mobility, higher hydrophobicity and stronger interaction with the perovskite layer than that of MPA-BT-BA. As a result, the device based-on MPA-2FBT-BA displays a better crystallization and morphology of perovskite layer with larger grain size and less non-radiative recombination.

Abnormal thermally-stimulated dynamic organic phosphorescence.

Dynamic luminescence behavior by external stimuli, such as light, thermal field, electricity, mechanical force, etc., endows the materials with great promise in optoelectronic applications. Upon thermal stimulus, the emission is inevitably quenched due to intensive non-radiative transition, especially for phosphorescence at high temperature.

Boosting the Plasmon-Mediated Electrochemical Oxidation of -Aminothiophenol with -Hydroxythiophenol as Molecular Cocatalyst.

Plasmon-mediated electrochemistry is an emerging area of interest in which the electrochemical reactions are enhanced by employing metal nanostructures possessing localized surface plasmon resonance (LSPR). However, the reaction efficacy is still far below its theoretical limit due to the ultrafast relaxation of LSPR-generated hot carriers. Herein, we introduce -hydroxythiophenol (PHTP) as a molecular cocatalyst to significantly improve the reaction efficacy in plasmon-mediated electrochemical oxidation of -aminothiophenol (PATP) on gold nanoparticles.

Pediatric paragonimiasis: a retrospective analysis of cases from a county in south-west China.

Introduction: The clinical manifestations of paragonimiasis are diverse and non-specific, and can easily lead to misdiagnosis. We aimed to analyze the clinical manifestations, laboratory features, treatment, and clinical outcome of children with paragonimiasis in order to improve recognition of this disease and avoid misdiagnosis.

Methods: Children diagnosed with paragonimiasis from August 2016 to July 2022 were included in the study.

Carbon coated heterojunction CoSe/SbSe nanospheres for high-efficiency sodium storage.

Multicomponent metal selenides with heterostructures are believed to effectively activate the surface pseudocapacitive contribution and improve the electrochemical dynamics, thus achieving high-performance anodes for sodium ion batteries (SIBs). Herein, a carbon coated CoSe/SbSe heterojunction (CoSe/SbSe@C) is designed and constructed an ion-exchange reaction between Co and Sb, and the subsequent selenization step. It is found that the hetero-structure and carbon shell effectively boost the charge transfer in the CoSe/SbSe@C composite electrode.

Strong synergy between gold nanoparticles and cobalt porphyrin induces highly efficient photocatalytic hydrogen evolution.

The reaction efficiency of reactants near plasmonic nanostructures can be enhanced significantly because of plasmonic effects. Herein, we propose that the catalytic activity of molecular catalysts near plasmonic nanostructures may also be enhanced dramatically. Based on this proposal, we develop a highly efficient and stable photocatalytic system for the hydrogen evolution reaction (HER) by compositing a molecular catalyst of cobalt porphyrin together with plasmonic gold nanoparticles, around which plasmonic effects of localized electromagnetic field, local heating, and enhanced hot carrier excitation exist.

Simple, Skin-Attachable, and Multifunctional Colorimetric Sweat Sensor.

In situ analysis of sweat provides a simple, convenient, cost-effective, and noninvasive approach for the early diagnosis of physical illness in humans and is particularly useful in family care. In this study, a flexible and skin-attachable colorimetric sweat sensor for multiplexed analysis is developed using a simple, cost-effective, and convenient method. The obtained sweat sensor can be used to simultaneously detect glucose, lactate, urea, and pH value in sweat, as well as sweat loss and skin temperature.

Dopant-Free Hole Transporting Material Based on Nonconjugated Adamantane for High-Performance Perovskite Solar Cells.

A new dopant-free hole transporting material (HTM) 4',4‴,4‴'',4‴''''-(adamantane-1,3,5,7-tetrayl)tetrakis(N,N-bis(4-methoxyphenyl)-[1,1'-biphenyl]-4-amine) (Ad-Ph-OMeTAD) (named FDY for short), which consists of a nonconjugated 3D bulky caged adamantane (Ad) as the core, triphenyl amines as side arms, and phenyl units as a linking bridge, is synthesized and applied in an inverted planar perovskite solar cell (PSC). As a result, the champion device with FDY as HTM yields an impressive power of conversion efficiency (PCE) of 18.69%, with J = 22.

Unveiling the additive-assisted oriented growth of perovskite crystallite for high performance light-emitting diodes.

Solution-processed metal halide perovskites have been recognized as one of the most promising semiconductors, with applications in light-emitting diodes (LEDs), solar cells and lasers. Various additives have been widely used in perovskite precursor solutions, aiming to improve the formed perovskite film quality through passivating defects and controlling the crystallinity. The additive's role of defect passivation has been intensively investigated, while a deep understanding of how additives influence the crystallization process of perovskites is lacking.

Effects of Oxygen Atoms Introduced at Different Positions of Non-Fullerene Acceptors in the Performance of Organic Solar Cells with Poly(3-hexylthiophene).

With the development of large-area fabrication technologies for organic solar cells (OSCs), poly(3-hexylthiophene) (P3HT) is the best choice as a photovoltaic donor polymer because it can be easily synthesized in the scale of kilograms at low cost. However, non-fullerene acceptors (NFAs) matching with P3HT for high performance OSCs are very rare. Herein, by introducing oxygen atoms into the side chains or the fused-ring core of indaceno[1,2-:5,6-']dithiophene, we synthesized two new A-A-D-A-A type NFAs, where benzotriazole (BTA) and 2-(1,1-dicyanomethylene)rhodanine were used as the bridged A and terminal A, respectively.

Perovskite light-emitting diodes based on spontaneously formed submicrometre-scale structures.

Light-emitting diodes (LEDs), which convert electricity to light, are widely used in modern society-for example, in lighting, flat-panel displays, medical devices and many other situations. Generally, the efficiency of LEDs is limited by nonradiative recombination (whereby charge carriers recombine without releasing photons) and light trapping. In planar LEDs, such as organic LEDs, around 70 to 80 per cent of the light generated from the emitters is trapped in the device, leaving considerable opportunity for improvements in efficiency.

A-A-D-A-A Type Non-Fullerene Acceptors with 2-(1,1-Dicyanomethylene)rhodanine as the Terminal Groups for Poly(3-hexylthiophene)-Based Organic Solar Cells.

2-(1,1-Dicyanomethylene)rhodanine (RCN) is an important electron-deficient terminal unit to build non-fullerene acceptors (NFAs) having been realized high power conversion efficiency (PCE) beyond 12% with complicated p-type polymer as electron donor. However, the photovoltaic properties of RCN-based NFAs are unsatisfied when paired with the classic p-type polymer poly(3-hexylthiophene) (P3HT). In order to make a contribution in this regard, we designed two RCN-based small molecular acceptors with A-A-D-A-A structure, BT3 and BTA3, where benzothiadiazole (BT) and benzotriazole (BTA) are bridged A segments, respectively, to modulate the optoelectronic properties.

Fluorination Triggered New Small Molecule Donor Materials for Efficient As-Cast Organic Solar Cells.

Solution-processable small molecules (SMs) have attracted intense attention due to their definite molecular structures, less batch-to-batch variation, and easier structure control. Herein, two new SM donors based on substituted isatin unit (DI3T, DI3T-2F) are synthesized and applied as electron donors with the mixture of PC BM to construct organic photovoltaics. As a result, 5,6-difluoro isatin derivative (DI3T-2F) obtains a power conversion efficiency of 7.

N-annulated perylene-substituted and fused porphyrin dimers with intense near-infrared one-photon and two-photon absorption.

Fusion of two N-annulated perylene (NP) units with a fused porphyrin dimer along the S0-S1 electronic transition moment axis has resulted in new near-infrared (NIR) dyes 1 a/1 b with very intense absorption (ε>1.3×10(5) M(-1) cm(-1)) beyond 1250 nm. Both compounds displayed moderate NIR fluorescence with fluorescence quantum yields of 4.

Enantiomeric separation of biaryl atropisomers using cyclofructan based chiral stationary phases.

Normal phase chiral HPLC methods are presented for the enantiomeric separation of 30 biaryl atropisomers including 18 new compounds recently produced via a novel synthetic approach. Three new cyclofructan based chiral stationary phases were evaluated. Separations were achieved for all but six analytes and the LARIHC™ CF6-P alone provided 15 baseline separations.

Organocatalytic aryl-aryl bond formation: an atroposelective [3,3]-rearrangement approach to BINAM derivatives.

Herein we disclose an organocatalytic aryl-aryl bond-forming process for the regio- and atroposelective synthesis of 2,2'-diamino-1,1'-binaphthalenes (BINAMs). In the presence of catalytic amounts of axially chiral phosphoric acids, achiral N,N'-binaphthyl hydrazines undergo a facile [3,3]-sigmatropic rearrangement to afford enantiomerically enriched BINAM derivatives in good to excellent yield. This transformation represents the first example of a metal-free, catalytic C(sp(2))-C(sp(2)) bond formation between two aromatic rings with concomitant de novo atroposelective installation of an axis of chirality.

Elusive metal-free primary amination of arylboronic acids: synthetic studies and mechanism by density functional theory.

Herein, we disclose the first metal-free synthesis of primary aromatic amines from arylboronic acids, a reaction that has eluded synthetic chemists for decades. This remarkable transformation affords structurally diverse primary arylamines in good chemical yields, including a variety of halogenated primary anilines that often cannot be prepared via transition-metal-catalyzed amination. The reaction is operationally simple, requires only a slight excess of aminating agent, proceeds under neutral or basic conditions, and, importantly, can be scaled up to provide multigram quantities of primary anilines.

N-heterocyclic carbene-catalyzed tandem aza-benzoin/Michael reactions: on site reversal of the reactivity of N-Boc imines.

A tandem NHC-catalyzed aza-benzoin/Michael reaction has been developed as a method to efficiently produce dihydroindenones and pyrrolidinone-containing tricycles. The novel reaction pattern involves tert-butyl aryl(tosyl)methylcarbamates reacting as both electrophile and nucleophile on the same carbon.

N-heterocyclic carbene catalyzed ring expansion of formylcyclopropanes: synthesis of 3,4-dihydro-alpha-pyrone derivatives.

N-Heterocyclic carbene catalyzed ring expansion of readily accessible 2-acyl-1-formylcyclopropanes was developed. With 5 mol % of triazolium salt 5 and 30 mol % of DBU, ring expansion of various 2-acyl-1-formylcyclopropanes led to 3,4-dihydro-alpha-pyrones in good to excellent yields.

Asymmetric Friedel-Crafts reaction of 4,7-dihydroindoles with nitroolefins by chiral Brønsted acids under low catalyst loading.

Slowly does it! By adding the substrate by a syringe pump, a highly efficient Friedel-Crafts reaction of 4,7-dihydroindoles with nitroolefins was realized with 0.5 mol % of a chiral phosphoric acid. The Friedel-Crafts alkylation, together with a subsequent oxidation of the product, led to 2-substituted indoles in excellent enantiomeric excesses, which can be easily transformed to enantioenriched tetrahydro-gamma-carbolines.