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Enantiomer-specific oriented attachment (abbreviation ESOA), a non-classical crystallization phenomenon, has been used for chiral crystal separation since Viedma for symmetry breaking of chiral substances. The so-called enantiomer-specific oriented attachment is mainly manifested by spontaneous chiral recognition of neighboring crystals during self-assembly through specific crystal faces, which leads to chiral amplification, and thus the possible formation of purely chiral crystal aggregates. However, as of now, this method enables chiral separation of achiral molecules, while it is rarely applied in the chiral separation of conglomerates. In view of this, we verified the stability and practicality of the ESOA method in chiral crystal separation by N-benzoylglycine and N-succinopyridine from the perspective of achiral molecules and conglomerates, respectively. Besides, we tried to explore whether ESOA can be used for the resolution of racemic compounds. To this aim, we boiled ethanol aqueous (VEtOH : VWater = 3 : 2) saturated solutions of DL -isoleucine, DL -leucine or DL -valine, but did not succeed in obtaining a single chiral crystal agglomerate. This is not the result we expected, but it reinforces the fact that most of the conditions for the success of the ESOA method are that the chiral substrate is a conglomerate. And it appears that we have discovered a way to prepare a conglomerate of DL -isoleucine, DL -leucine, and DL -valine on a large scale by this method, with a view to playing a role in other special complex chiral drugs in the future. [ABSTRACT FROM AUTHOR]

An innovative solid-phase microextraction (SPME) fiber coating, melamine–formaldehyde resin (MFR), was synthesized with a green cross-linker (paraformaldehyde), and it exhibited high heat resistance (up to 350 °C). Seven polycyclic aromatic hydrocarbons (PAHs) were chosen as analytes, and the results demonstrated the MFR-based SPME fiber's exceptional enrichment capabilities and efficient extraction, with high enrichment factors and significantly improved efficiency compared to the conventional polydimethylsiloxane (PDMS) fibers. The unique superiority of the MFR was attributed to its strong π–π interactions and amino-associated enhancement, as well as its porous structure and rough surface, which provided abundant adsorption sites and facilitated rapid mass transport of analytes. Furthermore, the preparation conditions of the MFR-coated SPME fiber were compared with those of commercially available and reported fibers, emphasizing the advantages of the MFR-coated fiber, such as its simplicity, cost-effectiveness, reproducibility, and eco-friendliness. The MFR-based SPME fiber exhibited significant advantages, including high enrichment factors (ranging from 1906- to 7153-fold) for PAHs and good fiber-to-fiber reproducibility (8.7–14.6%), outperforming commercially available PDMS fibers by a factor of 4.9–82.8-fold. This study also considered important factors affecting the extraction process, such as ionic strength, temperature, and time, and optimized these parameters for the best extraction efficiency. The greenness of the developed method was assessed using the Analytical Eco-Scale, and the results showed that it was green in terms of reagent dosage, energy consumption, and waste. The developed headspace solid phase microextraction–gas chromatography–tandem mass spectrometry (HS-SPME-GC-MS/MS) method based on the MFR coating exhibited excellent precision, accuracy, and repeatability, making it a reliable method for the determination of trace PAHs in environmental water samples. [ABSTRACT FROM AUTHOR]

Crystallization is an important unit operation in industry, and proteins are widely studied owing to their biological activity and multiple functions. Protein crystals can not only facilitate the elucidation of protein structural information but also have important prospects in biopharmaceuticals. However, owing to their high molecular weight and complex structure, most proteins are difficult to crystallize or the crystallization processes are difficult to control effectively. This paper aims to provide an overview of recent reinforcement techniques for protein crystallization. Several important additive applications and principles in protein crystallization are comprehensively reviewed, including ionic liquids (ILs), deep eutectic solvents (DESs), and molecularly imprinted polymers (MIPs). The mechanism of external fields, including magnetic, electric, ultrasonic, shear, and light fields, enhancing protein crystallization are described and summarized. Finally, the challenges and future research prospects of protein crystallization are proposed. This work is expected to guide the rational design of the protein crystallization process. [ABSTRACT FROM AUTHOR]

Engineering hierarchical heterostructure materials has been recognised as a challenging but prepossessing strategy for developing hybrid supercapacitors. Thus, a Ni–Co PBA derived 3D/1D heterostructure NiO/NiCo2O4 based layered double hydroxide on carbon cloth (CC/NiO/NiCo2O4/NiMn-LDH) as a battery-type electrode was successfully designed via a controllable hydrothermal method. The 3D Ni–Co PBA nanocubes served as scaffolds, providing more space for the nickel-cobalt precursors to grow and then calcine to form a continuous conductive layer of 3D/1D CC/NiO/NiCo2O4. Subsequently, 2D ultrathin NiMn-LDH nanosheets were uniformly anchored on 3D/1D NiO/NiCo2O4, resulting in a unique hierarchical structure that effectively addressed the restacking issue and dead volume of NiMn-LDH, contributing to increased charge and electron transport rates, which promoted the reaction kinetics. Benefiting from abundant interfaces with the open channels of the nanoarchitecture, the CC/NiO/NiCo2O4/NiMn-LDH electrode showed an exceptional specific capacity of 1593.0 C g−1 at 1 A g−1 and a desirable rate performance of 92.9% at a current density of 8 A g−1. Surprisingly, HSC devices can achieve an ideal specific energy of 44.28 W h kg−1 at a specific power of 108.22 W kg−1 with 97.59% cycling durability after 10 000 consecutive charge/discharge cycles. These remarkable properties indicate that the designed novel hierarchical heterostructure electrode has great potential for broad applications in electrochemical energy storage systems. [ABSTRACT FROM AUTHOR]

To explore the effects of lattice vibration and molecular interaction on their formation and structure, as well as their mechanical properties, vanillin cocrystals with nicotinamide and isonicotinamide were synthesized and characterized by time-domain Terahertz spectroscopy. The lattice vibrations of these cocrystals, as well as their individual components, were investigated using the dispersion-corrected density functional theory. The simulated terahertz spectra successfully were highly consistent with their experimental spectra. Typical intensive modes of vanillin and the cocrystals were discussed in terms of the motions of hydrogen bonds. The effect of lattice vibration on cocrystal structures was further studied to gain insights into their thermodynamic stability. Geometrical values of the computationally optimized structure were calculated using density functional theory at B3LYP/6-31(d,p) to obtain the highest occupied molecular orbitals and lowest unoccupied molecular orbitals of the cocrystal. The Hirshfeld surface and the molecular electrostatic potential were explored to study the interactions between the individual component of the cocrystals. The mechanical properties of the cocrystals were also calculated using modern quantum chemical methods. This study further highlights the consistency of computational results with crystallographic values, ensuring that the computational modeling of the cocrystals is equally important for predicting their stable geometries and applications. [ABSTRACT FROM AUTHOR]

COF-LZU1 with nanotube-like morphology has been synthesized with high crystallinity and pore volume in the presence of trimesic acid as a template. The as-synthesized COF nanotubes consist of a stack of plates with a diameter of about 100 nm with a hollow channel inside of about 20 nm. [ABSTRACT FROM AUTHOR]

The pathological mineralization of calcium oxalate monohydrate (COM) crystals in vivo inevitably brings renal injury wherein natural macromolecules play an indispensable role in regulating the process. However, the role of macromolecules in crystal growth is more complicated and less well understood. In this study, we innovatively propose two proteins extracted from earthworms, lumbrokinase (LRK) and earthworm protein (EP), as potent modifiers of calcium oxalate (CaOx) crystals. Our research shows that LRK and EP inhibit COM formation and initiate the calcium oxalate dihydrate (COD) phase, which is more easily excreted out of the body. Through a series of combined macroscopic and microscopic experimental techniques, we reveal the site-specific adsorption of inhibitors on the COM (121¯) and (021) surface, resulting in a reduction in the aspect ratio. In situ atomic force microscopy (AFM) measurements show that LRK and EP specifically inhibit the advancement of COM surface steps through more than one inhibition mode. In general, the discovery of natural macromolecules from earthworms as potent inhibitors of COM crystal formation provides some insights into the appropriate formulation of inhibitors, which could prevent the formation of undesired stones in the kidney. Our findings shed light on nature's remarkable mineralization capabilities and outline fabrication strategies for advanced materials. [ABSTRACT FROM AUTHOR]

Uric acid (UA) is the end product of purine metabolism and is widely found in nature. Excess uric acid will result in the deposition of pathological uric acid crystals in the kidney. However, few studies have focused on the effects of components in the human body on the crystallization of uric acid. Herein, we found multiple effects of alkali metals (Na+, K+) on uric acid dihydrate (UAD) crystal growth, which is one of the main components of urinary stones. Optical microscopy (OM) and scanning electron microscopy (SEM) were employed to detect the crystal morphology, and long rod-like crystals and hierarchical crystals were found in the presence of Na+ and K+, respectively. Powder X-ray diffraction (PXRD) and micro-Raman spectroscopy verified that the crystal structure remained unchanged in the presence of ions. In addition, single-crystal growth experiments revealed that Na+ inhibited growth along [010] and [100], and K+ promoted growth along [100] but suppressed growth along [010]. The step growth of the UAD crystal was measured by atomic force microscopy (AFM), which indicated the inhibition of crystal growth by Na+ due to kink blocking, yet the promotion of crystal growth by K+ resulted from rough growth. Our studies showed that ions in the human body not only can maintain electrolyte balance but also can affect the crystallization of pathological crystals, which provides a suggestion for a rational diet for patients with hyperuricemia and urinary stones. [ABSTRACT FROM AUTHOR]

Hybrid supercapacitors (HSCs) as a novel electronic device for electrical energy storage have attractive prospects due to their high specific power and fast charge/discharge rates. However, the low gravimetric energy density, sluggish frequency reply, and relatively low voltage range of HSCs limit their practical applications. Meanwhile, efficient energy storage faces challenges such as building effective electrode microstructures. Here, interfacial and structural engineering by developing a disordered structure, creating a synergy interface, and introducing an amorphous and crystalline synergistic system is employed to tailor their electrochemical properties. The resulting 1D crystalline NiCo2O4 anchored on carbon cloth (CC/NiCo2O4) can improve the kinetics of chemical reactions, and the amorphous "short-range order" and sheet-like two-dimensional structure of NiCo-(HPO4)2·H2O (NiCo–P) are beneficial to expose more active sites, and easily alleviate the volume change of the kinetic process. Thus, the obtained CC/NiCo2O4@NiCo–P exhibits a high specific capacity of 1254.2 C g−1 at 1 A g−1, a remarkable specific energy of 54.83 W h kg−1 and an outstanding cycling stability of 80.2%. By density functional theory (DFT) calculations, it is found that the superior electrical conductivity and strong adsorption to OH– of the CC/NiCo2O4@NiCo–P hybrid structure provide powerful theoretical help for improving electrochemical performance. This work provides new insights into the design of HSCs with enhanced properties and enables applications of crystalline-amorphous materials for energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

The pressure- and temperature-dependent luminescence properties of M′-phase Nd3+:YTaO4 synthesized by a molten salt method are presented. Ten near-infrared emission lines originating from the transitions between the two Stark levels R1,2 of the 3F3/2 state and the five Stark levels Z1,2,3,4,5 of the 4I9/2 state for the doped Nd3+ ions can be clearly identified. All these emission lines are found to shift linearly with pressure in a range up to ∼11 GPa. The R2,1 → Z5 emission lines have larger pressure sensitivities, which are 16.44 and 14.27 cm−1 GPa−1. The intensities of all the emission lines evolve with pressure non-monotonically, and peak at ∼1 GPa. The R1 → Z4,5 and R2 → Z1 emission lines can be obviously narrowed under the hydrostatic pressure, and broadened under the non-hydrostatic pressure, indicating their potential capability for reflecting the characteristic of a pressure environment. The intensity ratio of the R2,1 → Z5 emission lines exhibits a large temperature dependence, with a relative sensitivity between 0.129% and 0.108% K−1 in the physiological temperature range of 290–320 K. Thermal variations of the spectral positions and widths of the R2,1 → Z5 emission lines are also investigated. A high thermal stability for the position of the R2 → Z5 emission line is revealed. Based on the experimental results, the advantages and potential of Nd3+:YTaO4 as a multi-functional sensor for pressure and temperature are discussed. [ABSTRACT FROM AUTHOR]

Calcium D -pantothenate, also known as VB5, is one of the most important feed additives. It typically assumes a needle-like morphology that easily agglomerates, resulting in poor flowability and low bulk density. Here, we develop a route to prepare calcium D -pantothenate in a block-like morphology with good flowability and high bulk density. Also, the solvent-mediated phase transformation of calcium D -pantothenate methanol solvate (D-PC·MeOH) into D -pantothenate tetramethanol monohydrate (D -PC·4MeOH·H2O) was investigated by in situ ATR-FTIR spectrometry and Raman spectrometry, and the data was subsequently correlated by the Johnson–Mehl–Avrami model. Results demonstrate that the rate-controlling step was the nucleation and growth of D-PC·4MeOH·H2O. Careful control over the thermal transformation process of D-PC·4MeOH·H2O enabled the formation of solvent-free calcium D -pantothenate in a block-like morphology. Molecular dynamics simulations enabled a deeper understanding of the effects of temperature on the phase transformation process. This work provides a framework to scale the production of calcium D -pantothenate to industrial levels. [ABSTRACT FROM AUTHOR]

In this work, the influence of sodium dodecyl benzene sulfonate (SDBS) on the primary nucleation and growth of thiamine nitrate (VB1) has been investigated. At a given supersaturation, SDBS significantly impedes the nucleation rate of VB1. The results were analyzed through the probability distribution function of the induction time. Furthermore, the growth rate of VB1 in pure water and in the presence of SDBS was determined by single seed crystal growth experiments. It was found that the retardation by SDBS of the axial direction growth of VB1 crystals is much stronger than that of the radial direction growth. Molecular dynamics simulations (MD) were employed to delineate the effects of SDBS on the nucleation and growth of VB1. The MD simulation results manifested that the strong steric hindrance of SDBS molecules, the hydrogen-bonding and electrostatic interactions between SDBS molecules and VB1 molecules hinder the nucleation rate of VB1. Moreover, the results revealed the highest bonding energy between SDBS and the (1 0 0) surface, and the bonding energies between SDBS and all corresponding surfaces obey the following trend: (1 0 0) ＞ (1 1 0) ＞ (1 1 1) ＞ (1 0 2) ＞ (1 0 −2) ＞ (0 1 1) ＞ (0 0 2), which can provide a reasonable explanation for the experimental results. [ABSTRACT FROM AUTHOR]

Lithium metal–sulfur (Li–S) batteries have gained wide attention due to extremely high energy density, but their application was hindered by the challenges related to both the sulfur cathode and Li anode. Herein, we designed dual functional, highly ordered, and interconnected mesoporous carbon (MPC) to address the challenges related to the cathode and anode simultaneously. On the anode, a thin layer of MPC annealed at 500 °C (MPC-500) was introduced to mechanically suppress Li dendrite growth, which provided interfacial protection on the Li metal and stabilized the Li plating/stripping. This novel anode showed excellent cycling stability at a high current density of 3 mA cm−2. On the cathode, MPC annealed at 1300 °C (MPC-1300) was utilized to confine sulfur. The interconnected mesoporous carbon sphere with a large surface area significantly alleviated the shuttle effect, which contributes to the cycling stability of the Li–S battery. Meanwhile, the conductive carbon promotes electron transfer. When a Li–S full cell was assembled with MPC-500 and MPC-1300 as an anode interface layer and cathode additive, respectively, an exceptional reversible capacity of 607 mA h g−1 was achieved at a discharge rate of 1 C (1675 mA g−1) and maintained at a high capacity retention of 87.5% after 100 cycles. [ABSTRACT FROM AUTHOR]

Effective intervention against ischemic stroke requires delivery of potent neuroprotective drugs to the brain. Tanshinone IIA (TSIIA), the major bioactive ingredient extracted from the root of Salvia miltiorrhiza Bunge, is a proven neuroprotective compound, but its therapeutic application is hampered by chemical instability, low solubility, and inability to cross the blood brain barrier (BBB). Herein we report that a nanoformulation with a high-loading of TSIIA functionalized with Angiopep-2 effectively increased its brain accumulation by ∼12 fold, reduced infarct volume in an experimental stroke model by 2 fold, and augmented rat motor function scores after stroke by 60%. We confirm that the anti-ischemic stroke is mediated by inhibition of neuronal apoptosis, depletion of proinflammatory cytokines, and reversal of intracellular calcium [Ca2+]i overload in neurons. Moreover, we reveal for the first time that the underlying molecular mechanism for this formulation of TSIIA involves inhibition of the inflammatory signaling pathway HMGB1/TLRs/MyD88/NF-κB. [ABSTRACT FROM AUTHOR]

C-H carboxylation of furoic acid (FA) with CO 2 is an atom-efficient strategy to produce 2,5-furandicarboxylic acid (2,5-FDCA) from lignocellulose. The existing carbonate-promoted CO 2 carboxylation processes rely on the use of large amounts of expensive Cs 2 CO 3 as a deprotonating reagent and molten salt. Substitution of Cs with other cheap and abundant alkali ions (such as K and Na) can reduce the use of Cs, but it faces the problem of a low yield of 2,5-FDCA. This study found that the addition of catalytic amounts of ZnCl 2 as a Lewis acid can increase the yield of 2,5-FDCA in the CO 2 carboxylation reaction of Na/K-FA in a molten salt reaction system. 1 H NMR analysis and DFT calculations confirmed that ZnCl 2 coordinates with the furan ring through electron transfer from the conjugated furan ring to Zn 2+ , thereby activating the H at the C 5 position of Na/K-FA. This coordination lengthened the C 5 -H bond and lowered its heterolytic dissociation energy, making it more susceptible to being deprotonated by CO 3 2- and subsequently carboxylated by CO 2 . The developed Lewis acid coordination strategy provides a new idea for the efficient construction of C-C bonds between CO 2 and aromatics through carbonate-promoted C-H carboxylation.

Nanolithography techniques providing good scalability and feature size controllability are of great importance for the fabrication of integrated circuits (IC), MEMS/NEMS, optical devices, nanophotonics, etc. Herein, a cost-effective, easy access, and high-fidelity patterning strategy that combines the high-resolution capability of maskless plasmonic lithography with the spatial morphology controllability of grayscale lithography is proposed to generate the customized pattern profile from microscale to nanoscale. Notably, the scaling effect of gap size in plasmonic lithography with a contact bowtie-shaped nanoaperture (BNA) is found to be essential to the rapid decay characteristics of an evanescent field, which leads to a wide energy bandwidth of the required optimal dose to record pattern in per unit volume, and hence, achieves the volumetrically scalable control of the photon energy deposition in the space more precisely. Based on the proper calibration and cooperation of pattern width and depth, a grayscale-patterned map is designed to compensate for the dose difference caused by the loss of the high spatial frequency component of the evanescent field. A Lena nanostructure with varying feature sizes by spatially modulating the exposure dose distribution was successfully demonstrated, and besides, we also successfully generated a microlens array (MLA) with high uniformity. The practical patterning method makes plasmonic lithography significant in the fabrication of functional nanostructures with high performance, including metasurfaces, plasmonics, and optical imaging systems., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The pressure- and temperature-dependent luminescence properties of M'-phase Nd 3+ :YTaO 4 synthesized by a molten salt method are presented. Ten near-infrared emission lines originating from the transitions between the two Stark levels R 1,2 of the 3 F 3/2 state and the five Stark levels Z 1,2,3,4,5 of the 4 I 9/2 state for the doped Nd 3+ ions can be clearly identified. All these emission lines are found to shift linearly with pressure in a range up to ∼11 GPa. The R 2,1 → Z 5 emission lines have larger pressure sensitivities, which are 16.44 and 14.27 cm -1 GPa -1 . The intensities of all the emission lines evolve with pressure non-monotonically, and peak at ∼1 GPa. The R 1 → Z 4,5 and R 2 → Z 1 emission lines can be obviously narrowed under the hydrostatic pressure, and broadened under the non-hydrostatic pressure, indicating their potential capability for reflecting the characteristic of a pressure environment. The intensity ratio of the R 2,1 → Z 5 emission lines exhibits a large temperature dependence, with a relative sensitivity between 0.129% and 0.108% K -1 in the physiological temperature range of 290-320 K. Thermal variations of the spectral positions and widths of the R 2,1 → Z 5 emission lines are also investigated. A high thermal stability for the position of the R 2 → Z 5 emission line is revealed. Based on the experimental results, the advantages and potential of Nd 3+ :YTaO 4 as a multi-functional sensor for pressure and temperature are discussed.

(Ba 1- x Sm x )(Ti 1- x Cr x )O 3 (BSTC) and (Ba 1- x Sm x )(Ti 1-( x -0.01) Cr x -0.01 )O 3 (BSTC1) ceramics with a single-phase perovskite structure were prepared using a traditional solid state based method. The structure, microstructure, site occupations, valence states of Cr, photoluminescence, and dielectric properties of these ceramics were investigated using XRD, SEM, EDXS, RS, EPR, XPS, and dielectric measurements. All ceramics exhibit a fine-grained microstructure (0.7 μm). Three valence states of Cr ions were confirmed and Cr predominates as Cr 3+ enter the Ti 4+ sites with a stronger EPR signal (1.974). The RS bands of high-wavenumber were attributed to photoluminescence from Sm 3+ ions. The formation of defect complexes play leading roles in the removal of prevent the grain growth, and photoluminescence quenching. (Ba 1- x Sm x )(Ti 1-( x -0.01) Cr x -0.01 )O 3 (BSTC1) ceramics with amphoteric Sm 3+ ions exhibit a regular diffuse phase transition behavior, rapid T m -shifting rate of -24.3 °C/at% (Sm/Cr), higher lower tan  δ and x = 0.04 and 0.05 met the EIA Y5V specification., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A highly selective molecularly imprinted solid-phase extraction (MISPE) combined with liquid chromatography-ultraviolet detection was developed for the simultaneous isolation and determination of four plant hormones including indole-3-acetic acid (IAA), indole-3-propionic acid (IPA), indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA) in banana samples. The new molecularly imprinted microspheres (MIMs) prepared by aqueous suspension polymerization using 3-hydroxy-2-naphthoic acid and 1-methylpiperazine as mimic templates performed with high selectivity and affinity for the four plant hormones, and applied as selective sorbents of solid-phase extraction could effectively eliminate the interferences of the banana matrix. Good linearity was obtained in a range of 0.04-4.00 μg g(-1) and the recoveries of the four plant hormones at three spiked levels ranged from 78.5 to 107.7% with the relative standard deviations (RSD) of less than 4.6%. The developed MISPE-HPLC protocol obviously improved the selectivity and eliminated the effect of template leakage on quantitative analysis, and could be applied for the determination of plant hormones in complicated biological samples.