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The prevention of drying-induced cracking is crucial in maintaining the mechanical integrity and functionality of colloidal deposits and coatings. Despite exploring various approaches, controlling drying-induced cracking remains a subject of great scientific interest and practical importance. By introducing chain-like particles composed of the same material and with comparable size into commonly used colloidal suspensions of spherical silica nanoparticles, we can significantly reduce the cracks formed in dried particle deposits and achieve a fivefold increase in the critical cracking thickness of colloidal silica coatings. The mechanism underlying the crack suppression is attributed to the increased porosity and pore sizes in dried particle deposits containing chain-like particle, which essentially leads to reduction in internal stresses developed during the drying process. Meanwhile, the nanoindentation measurements reveal that colloidal deposits with chain-like particles exhibit a smaller reduction in hardness compared to those reported using other cracking suppression approaches. This work demonstrates a promising technique for preparing colloidal coatings with enhanced crack resistance while maintaining desirable mechanical properties. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis and characterization of various 1-thiaphenalene derivatives using a radical approach and photoredox catalysis. The reaction involves the intermolecular cyclization of 1-naphthalenesulfonyl chlorides and alkynes under mild conditions, resulting in high product diversity and broad functional-group tolerance. The authors provide a plausible reaction mechanism and experimental details for the synthesis of specific compounds, which were characterized using techniques such as NMR, HRMS, and IR spectroscopy. This information can be valuable for researchers studying these compounds or related topics. [Extracted from the article]

In this article, an experiment has been carried out with heat pipe vacuum or evacuated tube collector to produce water from atmospheric air. In this experiment, the regeneration and adsorption method has been adopted, that is, water has been produced through the adsorption and regeneration of desiccants. The desiccant is heated through a hot surface to facilitate its regeneration. Limited experiments have been conducted to obtain water through the regeneration of desiccant using a hot surface. For the condensation of water vapor, a novel box has been designed, named the "novel‐designed acrylic box." The water is collected in a measuring flask or beaker to determine its quantity. Silica gel desiccant has been used for the adsorption and regeneration of water vapors. In this experiment, the adsorption process for silica gel was carried out in two different ways. In the first method, 1 kg of silica gel was scattered on the copper tray, that is, inside the system, while in the second method, 1 kg of silica gel was scattered on the paper, that is, outside of the system. In the first case silica gel adsorbed 137 g water vapor, and in the second case, it adsorbed 232 g water vapor. In the first case of adsorption, 70 mL water was produced while in the second case of adsorption, 175 mL water was produced from ambient air. The system's maximum efficiency was found to be 4.9%. Effects of various parameters, such as solar intensity, ambient temperature, wind speed, and so forth, have been studied. [ABSTRACT FROM AUTHOR]

The given text provides a detailed account of the synthesis and characterization of several chemical compounds. The compounds synthesized include 1-(2,4-Dichlorophenyl)-3-(2,4-dimethoxyphenyl)-5-(trimethylsilyl)-1,4-pentadiyne, Hexacarbonyl[μ-[(1,2-η:1,2-η)-1-(2,4-dichlorophenyl)-1,4-pentadiyn-3-ol]]dicobalt, Hexacarbonyl[μ-[(1,2-η:1,2-η)-1-(2,4-dichlorophenyl)-3-(2,4-dimethoxyphenyl)-1,4-pentadiyne]], 1-(2,4-Dichlorophenyl)-3-(2,4-dimethoxyphenyl)-1,4-pentadiyne, (Z)-1-(2,4-Dichlorophenyl)-3-(2,4-dimethoxyphenyl)-1,4-pentadiene, and (E)-1-(2,4-Dichlorophenyl)-3-(2,4-dimethoxyphenyl)-1,4-pentadiene. The synthesis procedures and characterization data, including IR, NMR, and HRMS spectra, are provided for each compound. The supporting information for the article is also [Extracted from the article]

The simultaneous assay of duloxetine hydrochloride (DLX) and avanafil (AVN) in their pure forms, synthetic mixtures, and spiked human plasma was achieved using a novel, eco-friendly, sensitive, and specific HPTLC methodology that have been established and validated. Measuring the levels of co-administered antidepressants and sexual stimulants in biological fluids is an important step for individuals with depression and sexual problems. Separation was performed successfully using pre-coated silica gel 60-F254 as a stationary phase and a mobile phase composed of methanol, acetone, and 33% ammonia (8:2:0.05, v/v/v). Compact bands were produced by the optimized mobile phase that was chosen for development (Rf values were 0.23 and 0.75 for DLX and AVN, individually) after dual-wavelength detection for DLX and AVN at 232 and 253 nm, respectively. The results of polynomial regression analysis were exceptional (r = 0.9999 for both medicines) over concentration ranges of 5-800 and 10-800ng/spot for DLX and AVN, respectively. The quantitation limits were 4.69 and 9.53 ng/spot (0.31 and 0.94 µg/mL), whereas the detection limits were 1.55 and 3.15 ng/spot (0.63 and 1.91 µg/mL), for DLX and AVN, respectively. The International Council for Harmonization (ICH) criteria served as the basis for validating the established approach. Moreover, the proposed technique was evaluated in terms of greenness using four contemporary ecological metrics: The Analytical Greenness software (AGREE), the Green Analytical Procedure Index (GAPI), Eco-Scale, and the National Environmental Method Index (NEMI). Additionally, the Blue Applicability Grade Index (BAGI), a newly developed tool for evaluating the practicality (blueness) of procedures, was taken into consideration when evaluating the sustainability levels of the established approach. [ABSTRACT FROM AUTHOR]

Two rapid, precise, and sensitive stability-indicating high performance chromatographic methods for the measurement of Teriflunomide in its degradation products' existence were developed. These were RP-HPLC and HPTLC using UV detector. HPLC separation was accomplished utilizing Thermo BDS hypercil C18 column (250 × 4.6 mm, 5 μm) and acetonitrile: 0.03 M potassium dihydrogen phosphate: triethylamine (50:50:0.1%, by volume) as mobile phase at flow rate of 1mL/min. The separated peaks were detected at 250.0 nm. The densitometric approach was conducted utilizing HPTLC 60 F254 silica gel plates, and a developing system of benzene: ethanol: acetic acid (7.5:1:0.25, by volume) and detection was done at 250.0 nm. The developed approaches were evaluated regarding the International Conference on Harmonization (ICH) instructions. The calibration curves of both techniques were constructed with linearity ranges of (5-100) µg/mL and (2–10) µg /band, for HPLC and densitometric determination, consecutively. Teriflunomide was exposed to base and acid hydrolysis, oxidation using H2O2 and finally, thermal degradation as stated in ICH guidelines. The degradation product structures' elucidation was achieved through LC-MS. [ABSTRACT FROM AUTHOR]

The Applications of silica aerogel are limited due to its brittleness and low strength. As a result, it is essential to strengthen and toughen it. Organic nanofibers are one of the preferred reinforcement materials. In this work, we designed and fabricated flexible and compressible nanostructure-assembled aramid nanofiber/silica composites aerogel (ANF/SiO2 aerogel) to improve the mechanical strength and flexibility of silica aerogel without compromising thermal insulation properties. The aramid nanofiber/silica composite aerogels were prepared by immersing the aramid nanofiber wet gel into the silica sol for a certain period of time followed by freeze drying without solvent replacement. The surface modifier 3-aminopropyltriethoxysilane (APTES) was used as a coupling agent to form chemical linkage between the ANF fiber and silica gel. It was observed that APTES can effectively drive the silica sol to infuse into ANF hydrogel, promoting the assembly of silica gel onto the fiber surface and a uniform distribution in the network of ANF. The compressive resilience, thermal stability, and thermal insulation properties of the composite aerogels were evaluated by inducing the silica aerogel into the ANF network to form a protective layer on the fiber and change the pore structure in the ANF network. [ABSTRACT FROM AUTHOR]

This document provides technical information about the synthesis and characterization of three chemical compounds. The compounds are described in terms of their nuclear magnetic resonance (NMR) spectra, high-resolution mass spectrometry (HRMS) data, and physical properties. The text also acknowledges financial support from the CAS-TWAS fellowship. The information is presented in a scientific manner and may be useful for researchers studying organic chemistry. [Extracted from the article]

This document summarizes a study on the synthesis and characterization of various compounds, including trifluoromethyl arenes. The study focuses on the hydrolysis of the trifluoromethyl group to carboxylic acid, which is challenging but important for pharmaceutical applications. The authors propose a method using a combined base system that efficiently mediates this transformation. The document provides experimental procedures, spectral data, and acknowledges the use of an EPR apparatus from Tohoku University. The data obtained for the compounds synthesized in the study match those reported in the literature. [Extracted from the article]

[Display omitted] Colloidal suspensions of anisotropic particles are ubiquitous in particle-based industries. Consequently, there is a need to quantify the effects of particle shape on equilibrium phases and kinetic state transitions, particularly at lower aspect ratios (L / D ≈ 1–10). We present a new, colloidal system comprised of hollow, octadecyl-coated silica rods with 40 nm diameter with controlled aspect ratio and thermoreversible short-range attractions. Rheology and dynamic light scattering measurements on suspensions of these hollow adhesive hard rods with nominal aspect ratio ≈3 suspended in tetradecane exhibit thermoreversible gelation without complicating effects of gravitational settling. Small angle neutron scattering measurements of the microstructure are analyzed to determine the effective strength of attraction in the form of Baxter sticky parameter. Quantitative agreement is found with simulation predictions of the thermoreversible gel transition as a function of volume fraction, further validating a universal state diagram and providing guidance for the effects of aspect ratio on gelation. [ABSTRACT FROM AUTHOR]

[Display omitted] The controlled cation substitution is an effective strategy for optimizing the density of states and enhancing the electrocatalytic activity of transition metal oxide catalysts for water splitting. However, achieving tailored mesoporosity while maintaining elemental homogeneity and phase purity remains a significant challenge, especially when aiming for complex multi-metal oxides. In this study, we utilized a one-step impregnation nanocasting method for synthesizing mesoporous Mn-, Fe-, and Ni-substituted cobalt spinel oxide (Mn 0.1 Fe 0.1 Ni 0.3 Co 2.5 O 4 , MFNCO) and demonstrate the benefits of low-temperature calcination within a semi-sealed container at 150–200 °C. The comprehensive discussion of calcination temperature effects on porosity, particle size, surface chemistry and catalytic performance for the alkaline oxygen evolution reaction (OER) highlights the importance of humidity, which was modulated by a pre-drying step. The catalyst calcined at 170 °C exhibited the lowest overpotential (335 mV at 10 mA cm−2), highest current density (433 mA cm−2 at 1.7 V vs. RHE, reversible hydrogen electrode) and further displayed excellent stability over 22 h (at 10 mA cm−2). Furthermore, we successfully adapted this method to utilize cheap, commercially available silica gel as a hard template, yielding comparable OER performance. Our results represent a significant progress in the cost-efficient large-scale preparation of complex multi-metal oxides for catalytic applications. [ABSTRACT FROM AUTHOR]

The hydratable magnesium carboxylate (HMC) bonded castables have a high-level gas permeability while the mechanical strength decreased sharply during drying process. Silica-gel with high activity is a porous structure after drying and can potentially increase the intermediate-temperature strength without reducing the gas permeability of the castables. In this study, the mechanism of silica-gel modified the HMC, and the effects on the properties of the castables were investigated. The surface of the hydration products of HMC is covered with a thin protective layer of siloxane network. The proportion of fine permeable pores (0.1 μm ∼1 μm) increased, optimizing the connected network channels in the castables. Compared to the pure HMC bonded castables, with the HMC/silica-gel mass ratio of 2, the cold modulus of rupture of the castables increased by 2 times after heat treatment in the range of 400 °C ∼600 °C. Especially, the permeability constants Darcian k 1 and non-Darcian k 2 increased by 37 times and 38 times after heat treatment at 600 °C, respectively. [ABSTRACT FROM AUTHOR]

Tetraethoxysilane (TEOS) is the most commonly used silicon-based reinforcement agent for conserving art relics due to its cost-effectiveness and commercial maturity. However, the resulting silica gel phase is prone to developing cracks as the gel shrinks during the sol–gel process, potentially causing severe damage to the objects being treated. In this study, dodecyltrimethoxysilane (DTMS) was introduced into TEOS to minimize this shrinkage by adding elastic long chains to weaken the capillary forces. The gel formed from the DTMS/TEOS hybrid material was transparent and crack-free, featuring a dense microstructure without mesopores or micropores. It exhibited excellent thermal stability, with a glass transition temperature of up to 109.64 °C. Evaluation experiments were conducted on artificially aged, handmade bamboo paper. The TEOS-based hybrid material effectively combined with the paper fibers through the sol–gel process, polymerizing into a network structure that enveloped the paper surface or penetrated between the fibers. The surface of the treated paper displayed excellent hydrophobic properties, with no significant changes in appearance, color, or air permeability. The mechanical properties of the treated bamboo paper improved significantly, with longitudinal and transverse tensile strengths increasing by up to 36.63% and 44.25%, respectively. These research findings demonstrate the promising potential for the application of DTMS/TEOS hybrid materials in reinforcing paper relics. [ABSTRACT FROM AUTHOR]

Dexterity and perceptual abilities of the hand are crucial in virtual reality (VR) interactions. This necessitates haptic gloves capable of accurately measuring finger movements and ensuring comfort, a challenging combination that demands both high sensitivity and stretchability. A flexible sensor fabricated from semi‐solid material CNTs‐Inkpad composed of carbon nanotubes (CNTs) mixed with silica gel is proposed and its real‐time response can be achieved by controlling the ratio. Its semi‐solid form harnesses CNTs' high conductivity and sensitivity, avoiding structural cracking in solid CNTs during extensive stretching, thus the semi‐solid form can adapt to various hand gestures. This mechanism enables the CNTs‐Inkpad to function as strain sensors with high gauge factors (GF = 16.99) and high extensibility (350%). By integrating ten CNTs‐Inkpad sensors and five vibrators, a thin and lightweight haptic glove is developed with high sensitivity and stretchability. The glove enables collaborative measurement of all finger joints required for typical gestures in VR interactions, suitable for motion detection and haptic feedback. [ABSTRACT FROM AUTHOR]

Polystyrene and silica gel polymer hybrids derived from polystyrene and phenyltrimethoxysilane via π–π interactions were synthesized by a slight modification of the previous method. Spectroscopic evidence of the π–π interaction is provided. The obtained polymer hybrids were optically transparent, and no phase separation was observed by scanning electron microscopy measurements. In the FT-IR spectrum of the resulting polymer hybrids, the absorption peaks corresponding to C–H wagging vibration shifted to a lower wavenumber range as the content of silica in the hybrids increased. A UV–vis spectrum of the polystyrene and silica gel polymer hybrids showed a shoulder peak at around 260 nm that shifted toward longer wavenumbers side as the content of silica increased. These results clearly indicate that π–π interactions contribute to the formation of these transparent hybrids. [ABSTRACT FROM AUTHOR]

In this study, novel biomaterial that consisted entirely of bacterial products was developed with the approach of designing cost effective material for biomedical applications. With this aim, bacterial cellulose membranes (BCMs) which synthesized by Komagataeibacter intermedius were produced. Moreover, to impart antimicrobial properties to enhance the capacity of BCMs for biomedical usage, prodigiosin (PG) pigment of Serratia marcescens which presents wide range of antimicrobial activities was loaded to BCMs. Firstly, high yield of PG production was achieved, and then crude pigment was purified with silica gel column. The purified PG was characterized with thin layer chromatography and UV–visible spectrometry. The antimicrobial effect of the produced pigment on Gram-positive and negative bacteria and a yeast was investigated. The success of modification in PG-modified BCMs has been demonstrated by FTIR and SEM. Moreover, antimicrobial and antiadhesive ability of novel PG-BCMs were examined with disc diffusion and plate counting methods. As a result, it was established that PG-BCMs were able to inhibit the growth of all tested microorganisms. Furthermore, excellent antiadhesive effect was observed for the tested microorganisms with the inhibition rates of 82.05–96.25 %. Finally, cytotoxicity test with L929 cell line demonstrated that PG-BCM is biocompatible at a level that can be applied in in vivo studies. • Prodigiosin pigment obtained from S. marcescens ATCC 14756 was used to impart antimicrobial properties to bacterial cellulose produced by K. intermedius. • Bacterial cellulose functionalized with prodigiosin showed excellent antimicrobial activity against both Gram-positive and negative bacteria. • Prodigiosin loaded bacterial cellulose membranes inhibited the adhesion capacity of both bacteria and Candida yeast. [ABSTRACT FROM AUTHOR]

Hand warmers are used in cold environmental conditions to warm hands. Disposable air activated hand warmers and reusable hand warmers which generate heat by crystallization are present in the market. In the present study utilizing heat of wetting of silica gel and zeolites in warming hands was tested in a system simulated to warm hands by inserting warmer packages in knitted wool gloves. Sodium acetate solution was also tested as a reusable hand warmer by melting and recrystallization. While the commercial warmers released heat slowly for long period, dry silica gel and dry zeolite 4A released heat fast. Around 25% water and inert dilution materials should be used to limit the temperature rise in silica gel and zeolite 4A within reasonable limits. [ABSTRACT FROM AUTHOR]

Egypt suffers from limited water resources, which threatens food security and reduces the chances of horizontal expansion by reclaiming new desert lands. Therefore, it was necessary to achieve this target for the productivity and quality of crops under harsh conditions. Field experiments proceeded at the Nubaria research station under sandy soil conditions to evaluate the effects of different silicon sources (silica gel, algae rich in silicon, and potassium silicate) on sugar beet yield and quality under different irrigation regimes (100%, 75%, and 50%) of water requirement (WR) during the growing seasons of 2020 and 2021. Results showed that potassium silicate was most effective for increasing chlorophyll content and growth parameters compared with other sources under water stress conditions. Also, improved nutrient contents in the root and shoot of sugar beet gave the highest values on N (0.58%, 2.54%), P (0.132%, 0.318%), K (0.42%, 1.05%), Fe (67.18, 83.28 ppm), and Zn (11.29, 12.73 ppm) content, respectively, when applied with K2SiO3 compared with deficit irrigation conditions. Stimulating rich-Si remains the most effective for enhancing the growth, quality, and yield of sugar beet grown under deficit irrigation regimes, which makes plants more resistant to weather conditions and water stress. [ABSTRACT FROM AUTHOR]

Enzalutamide (ENZ), marketed under the brand name Xtandi® as a soft capsule, is an androgen receptor signaling inhibitor drug actively used in clinical settings for treating prostate cancer. However, ENZ's low solubility and bioavailability significantly hinder the achievement of optimal therapeutic outcomes. In previous studies, a liquid self-nanoemulsifying drug delivery system (L-SNEDDS) containing ENZ was developed among various solubilization technologies. However, powder formulations that included colloidal silica rapidly formed crystal nuclei in aqueous solutions, leading to a significant decrease in dissolution. Consequently, this study evaluated the efficacy of adding a polymer as a recrystallization inhibitor to a solid SNEDDS (S-SNEDDS) to maintain the drug in a stable, amorphous state in aqueous environments. Polymers were selected based on solubility tests, and the S-SNEDDS formulation was successfully produced via spray drying. The optimized S-SNEDDS formulation demonstrated through X-ray diffraction and differential scanning calorimetry data that it significantly reduced drug crystallinity and enhanced its dissolution rate in simulated gastric and intestinal fluid conditions. In an in vivo study, the bioavailability of orally administered formulations was increased compared to the free drug. Our results highlight the effectiveness of solid-SNEDDS formulations in enhancing the bioavailability of ENZ and outline the potential translational directions for oral drug development. [ABSTRACT FROM AUTHOR]

The development of thermal energy storage materials applied in various fields has been attracting considerable attention in recent years. In this paper, a series of 1,6-hexanediol (HDL)/silicon dioxide (SiO2) form-stable composite phase change materials (fs-CPCMs) with various mass percentage of HDL loadings were made through sol–gel technique. For HDL/SiO2 fs-CPCMs, HDL was served as PCM, and silica gel was acted as the supporting matrix to keep a stable state without leakage of the composites even the temperature was over 85 °C. The results from form-stability test and DSC measurements showed that the as-prepared fs-CPCM with the mass fraction of HDL at 70 wt% presented good form-stability, suitable melting point (43.5 °C), and reasonable fusion enthalpy of 130.9 J/g. Fourier transform infrared (FT-IR) spectroscopy indicated that only physical adsorption existed between the HDL and silica gel. Moreover, the thermal performance tests showed that the thermal energy storage and release rates of the as-prepared HDL/SiO2 fs-CPCM was enhanced compared to pure HDL. In summary, the as-prepared fs-CPCMs exhibit reasonable latent heats, good thermal stabilities, and reliability, which are promising candidates for energy-saving construction materials. [ABSTRACT FROM AUTHOR]

Mesoporous silica gel doped with dysprosium, lanthanum and modified with silver (Dy-Ag/MPS, La-Ag/MPS) was obtained by the template method. The physicochemical characteristics of the obtained catalyst were studied by scanning electron microscopy, X-ray fluorescence and X-ray diffraction analysis, inductively coupled plasma mass spectrometry and temperature-programmed reduction. In addition, the possibility of using obtained materials as an efficient and selective catalysts in the hydrogenation of a 1-heptyne/1-heptene mixture (with 30% of alkyne content) in a temperature range of 140–160 °C and a hydrogen pressure of 3 atm was studied. It was found that after 15 min from the start of the hydrogenation reaction at 140 °C on the La-Ag/MPS catalyst, total conversion of 1-heptyne was observed and selectivity for 1-heptene was 84%. Moreover, it was shown that on a Dy-Ag/MPS at 150 °C 1-heptyne conversion was 84%, the selectivity for alkene was 79%. Furthermore, with an increase in temperature to 160 °C, the conversion of 1-heptyne reaches 95%, the selectivity for 1-heptene—84%. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of α-l-threofuranosyl guanosine 3'-triphosphate (tGTP), which is an important building block for the construction of artificial genetic polymers. The traditional method for synthesizing tGTP involves a laborious and time-consuming process. However, the authors propose an alternative synthetic route using commercially available 6-chloropurine-2-amine, which simplifies the synthesis and reduces the use of hazardous solvents. The authors also compare two different methods for preparing tGTP nucleotides and conclude that the pyrene pyrophosphate approach is preferred due to its fewer synthetic steps. This improved approach could be advantageous for the large-scale synthesis of guanosine nucleosides. [Extracted from the article]

This article discusses the synthesis of 2-aminopyridine-modified peptide nucleic acids (PNAs) and their potential applications in research and diagnostics. PNAs are known for their high affinity and sequence specificity in binding to nucleic acids. The article describes the chemical modifications made to improve the properties of PNAs, such as replacing cytosine with pseudoisocytosine and using 2-aminopyridine as an alternative. The authors also outline the optimized synthetic route to produce the modified PNA monomers. The article provides detailed procedures and recommendations for the synthesis of PNAs using different synthesizers. Overall, the article offers valuable insights for researchers interested in the synthesis and applications of modified PNAs. [Extracted from the article]

This article discusses the synthesis of aryl-C-glycosides, specifically focusing on 2-deoxy-aryl-C-glycosides, which have potential biological activities. The authors present a new method using palladium catalysts for the synthesis of these compounds through 1,4-conjugate addition reactions. They conducted an optimization study to determine the best reaction conditions and found that palladium acetate and acetic acid were effective additives. The article also provides detailed information on the preparation and characterization of several compounds, including their chemical structures and physical properties. This information can be valuable for researchers studying these compounds or related chemical reactions. [Extracted from the article]

Shear history plays an important role in determining the linear and nonlinear rheological response of colloidal gels and can be used for tuning their structure and flow properties. Increasing the colloidal particle aspect ratio lowers the critical volume fraction for gelation due to an increase in the particle excluded volume. Using a combination of rheology and confocal microscopy, we investigate the effect of steady and oscillatory preshear history on the structure and rheology of colloidal gels formed by silica spheres and rods of length L and diameter D (L/D = 10) dispersed in 11 M CsCl solution. We use a non-dimensional Mason number, Mn (=Fvisc./Fattr.), to compare the effect of steady and oscillatory preshear on gel viscoelasticity. We show that after preshearing at intermediate Mn, attractive sphere gel exhibits strengthening, whereas attractive rod gel exhibits weakening. Rheo-imaging of gels of attractive rods shows that at intermediate Mn, oscillatory preshear induces large compact rod clusters in the gel microstructure, compared to steady preshear. Our study highlights the impact of particle shape on gel structuring under flow and viscoelasticity after shear cessation. [ABSTRACT FROM AUTHOR]

Thermal energy storage utilizing the adsorption of moisture from air is a promising energy storage technology due to its high energy density and minimum heat losses. Salt hydrates and salt hydrate composites, such as calcium chloride (CaCl2) and CaCl2-based composites, have shown favourable energy storage properties in this area of research. However, these materials have shown issues with stability due to swelling and deliquescence. In this work, CaCl2 was stabilized using three methods: impregnation into silica gel, encapsulation in methyl cellulose, and both impregnation and encapsulation stabilization techniques used simultaneously. Therefore, three CaCl2-based composites were synthesized. For the first composite, silica gel was impregnated with CaCl2. For the second composite, CaCl2 was encapsulated by methyl cellulose. For the third composite, silica gel was impregnated with CaCl2 and the CaCl2 was encapsulated with methyl cellulose. These samples were structurally characterized using scanning electron microscopy as well as Brunauer-Emmett-Teller (BET) to determine surface area, pore size distribution and nitrogen adsorption isotherms at 77 K. Water vapour adsorption isotherms were also determined at 25 °C for different relative humidities by dynamic vapor sorption (DVS). Similarly, LiCl-based composites were also synthesized and examined in this work, but issues of deliquescence, swelling, and agglomeration made the materials impractical to work with. To determine the prepared materials' thermal energy storage performance, 2–6 g of each sample was tested in a lab-scale apparatus. This process uses the exothermic adsorption of moisture from ambient air in an open thermal energy storage system. The CaCl2 impregnated silica gel that was encapsulated in methyl cellulose showed reasonably high stability and energy storage performance after 3 hydration and dehydration cycles with minimum agglomeration. An energy storage density of 241 kWh/m3 (0.87 GJ/m3) and specific energy of 630 Wh/kg (2268 kJ/kg) was achieved with this material for 90% inlet relative humidity after a regeneration at 90 °C. [ABSTRACT FROM AUTHOR]

Gastrointestinal mesenchymal tumors, as the most common mesenchymal tumors in the gastrointestinal tract, are adjuvantly treated with multi-targeted tyrosine kinase inhibitors, such as imatinib and sunitinib, but there are problems of drug resistance and complex methods of monitoring therapeutic agents. The pathogenesis of this disease is related to mutations in tyrosine kinase (KIT) or platelet-derived growth factor receptor α, an important target for drug therapy. In recent years, the screening of relevant tyrosine kinase inhibitors from traditional Chinese medicine has become a hotspot in antitumor drug research. In the current study, the KIT-SNAP-tag cell membrane chromatography (KIT-SNAP-tag/CMC) column was prepared with satisfying specificity, selectivity, and reproducibility by chemically bonding high KIT expression cell membranes to the silica gel surface using the SNAP-tag technology. The KIT-SNAP-tag/CMC-HPLC-MS two-dimensional coupling system was investigated using the positive drug imatinib, and the results showed that the system was a reliable model for screening potential antitumor compounds from complex systems. This system screened and identified three potential active compounds of evodiamine (EVO), rutaecarpin (RUT), and dehydroevodiamine (DEVO), which possibly target the KIT receptor, from the alcoholic extract of the traditional Chinese medicine Evodia rutaecarpa. Then, the KD values of the interaction of EVO, RUT, and DEVO with KIT receptors measured using nonlinear chromatography were 7.75 (±4.93) × 10−6, 1.42 (±0.71) × 10−6, and 2.34 (±1.86) × 10−6 mol/L, respectively. In addition, the methyl thiazolyl tetrazolium assay validated the active effects of EVO and RUT in inhibiting the proliferation of high KIT-expressing cells in the ranges of 0.1–10 µmol/L and 0.1–50 µmol/L, respectively. In conclusion, the KIT-SNAP-tag/CMC could be a reliable model for screening antitumor components from complex systems. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of isoquinolinone derivatives, specifically 3-amino-substituted isoquinolinones and dihydrophenanthridinediones. The authors explore different synthetic approaches and advancements in the synthesis of these derivatives. They also introduce glycosyl triazole-appended pyridinamide ligands and investigate their catalytic efficacy in the synthesis of these derivatives. The document provides detailed information about the synthesis process, purification methods, physical properties, and spectroscopic data of the compounds. It can be a valuable resource for researchers studying the synthesis and characterization of isoquinolinone derivatives. [Extracted from the article]

The addition of salt has a pronounced impact on the stability of nanoparticles. By varying the salt types and concentrations, the structure of spray-dried supraparticles from binary SiO 2 nanoparticle dispersions can be tuned from core-shell to Janus-like and well-mixed. The surface roughness and porosity are modified accordingly. In summary, this study presents a feasible way to synthesize particles with different supraparticular structures by elucidating the role of ionic strength on different sizes of nanoparticles. [Display omitted] The structure and texture of supraparticles determine their properties and performance, thus playing a critical role in research studies as well as industrial applications. The addition of salts is a well-known strategy to manipulate the colloidal stability of nanoparticles. In this study, this approach is used to tune the structure of spray-dried supraparticles. Three different salts (NaCl, CaCl 2 , and AlCl 3) were added to binary silica (SiO 2) nanoparticle dispersions (of 40 and 400 nm in size) to change their colloidal stability by lowering the electrostatic repulsion or enhancing the cation bridging. Dependent on the cation valence of the added salt and the nanoparticle size, the critical salt concentration, which yields nanoparticle agglomeration, is reached at different salt amounts. This phenomenon is exploited to tune the final structure of supraparticles - obtained by spray-drying binary dispersions - from core-shell to Janus-like to well-mixed structures. This consequently also tunes textural properties, like surface roughness and the pore system of the obtained supraparticles. Our results provide insights for controlling the structure of spray-dried supraparticles by manipulating the stability of binary nanoparticle dispersions, and they establish a framework for composite particle design. [ABSTRACT FROM AUTHOR]

The development of innovative methods for real-time surveillance of enzymatic activity determination processes is essential, particularly for insoluble substrate enzymatic assessments. In this work, a novel method for enzymatic activity determination was devised by assembling a 190 nm silica colloidal crystal (SCC) film onto a glass slide, coupled with Ordered Porous Layer Interferometry (OPLI) technology. By fixing the substrate of the enzyme on the surface of the silica sphere, a solid–liquid interface can be formed for monitoring enzymatic activity. The enzymatic activity is gauged by the change in the SCC film's thickness caused by the digestion of the loaded substrate. The procedure of chymotrypsin-mediated casein digestion was documented in real time, facilitating the examination of chymotrypsin's activity and kinetics. The newly-developed enzymatic activity determination method demonstrated exceptional sensitivity towards chymotrypsin activity, with a linear range spanning 0.0505–2.02 units per mg. Additionally, the method was extended to the assessment of fibrinolysis enzyme activity and kinetic analysis, yielding promising results. Therefore, this technique can serve as a real-time, user-friendly, cost-effective novel approach for enzymatic activity determination, providing fresh perspectives for enzymatic activity determination studies. [ABSTRACT FROM AUTHOR]

Gadolinium-silica (Gd-silica) gels were prepared via sol–gel route combined to γ-irradiation (0–30 kGy), starting from Tetra-Ethyl-Orthosilicate (Si(OCH2CH3)4, TEOS) and gadolinium nitrate Gd(NO3).6H2O used as raw materials. The phase transformation and morphology of the gels derived from both precursors were characterized by XRD and TEM analysis. Differential scanning calorimetry (DSC) under non-isothermal conditions was used to determine the crystallization activation energy (Ec) at different γ-doses (0, 8, 15, 25 and 30 kGy), using the methods suggested by Kissinger, Moynihan and Ozawa. XRD analysis of the samples calcined up to 1100°C for 2 h reveals the formation of gadolinium silicate (Gd4.67 (SiO4)3O) apatite crystalline phase with the presence of small traces of gadolinium pyrosilicate (Gd2Si2O7), the average particle sizes about 50 nm. TEM observations show spherical Gd-silicate nanoparticles homogeneously dispersed in silica matrix, the mean diameter size is about 40 nm. From DSC analysis, it was observed that the onset crystallization temperature (Tx) and peak crystallization temperature (Tc) both increase with increasing γ-dose. According to Kissinger, Moynihan and Ozawa models, the crystallization activation energies for Gd-silicate phase formation were found to be 465.2, 474.5 and 465.7 kJ mol−1, respectively for unirradiated samples and 429.1, 447 and 438 kJ mol−1 when the γ-irradiation reaches 30 kGy respectively. Results revealed that the values of Ec decreased when the γ-dose increases and attains the minimum value at the dose of 15 kGy and then increase at higher doses. The crystallization rate factor (K) was also seen to decrease with increasing of γ-dose. Gamma irradiation increases the crystallization peak temperature (Tc). The crystallization activation energy (Ec) estimated from the three models is in good agreement and much well with those reported for silicate systems. Gamma irradiation decreases the Ec and crystallization rate factor (K). These preliminary results can provide useful technical information for a better understanding and control of the crystallization process of this type of nanomaterial. [ABSTRACT FROM AUTHOR]

We investigated the flow acetalization of aldehydes and THP protection of alcohols using sulfonic acid-functionalized silica gel having hydroxy moiety (HO-SAS) as the solid acid catalyst. The reaction both aliphatic and aromatic aldehydes reacted with methanol within 5 min of residence time to give acetalization product in good to excellent yield. THP protection of primary, secondary, and tertiary alcohols proceeded well to the corresponding products. Both reactions did not require a neutralization process. Scalable syntheses were also achieved with continuous operation. The deprotection reactions were also effective using HO-SAS packed flow reactors. [ABSTRACT FROM AUTHOR]

This article discusses the chemical compounds found in Aconitum rockii, a plant native to China. The plant contains diterpenoid alkaloids with pharmacological effects, such as pain relief and anti-inflammatory properties. The researchers isolated 21 compounds from the plant, some of which were previously unknown. They tested these compounds for their ability to inhibit the growth of cervical cancer cells and found that four compounds showed significant inhibition. The article also provides detailed information on the experimental methods used in the study, including cell culture and drug treatment. Additionally, it includes information on the chemical structures and spectroscopic data of several compounds. The research was supported by the National Natural Science Foundation of China. [Extracted from the article]

This article discusses the compounds found in the leaves and stems of the plant Cassia nodosa, which is widely distributed in several countries and used in traditional medicine. Previous studies have identified different types of compounds in the Cassia genus, but there are limited reports on C. nodosa specifically. In this study, 17 compounds were isolated and characterized, including anthraquinones, flavonoids, terpenoids, alkaloids, and steroids. The compounds were identified using spectroscopic methods and compared with existing literature data. The research was supported by the Key Laboratory and Science and Technology Innovation Team of Higher Education in Yunnan, China. [Extracted from the article]

Aqueous complexation has long been considered the only viable means of transporting gold to depositional sites in hydrothermal ore-forming systems. Here, we present direct evidence supporting an alternative hypothesis, namely, the transport of gold as colloidal particles. We observed nano-scale gold particles adsorbed on halloysite and micro-scale gold particles in altered rocks by TEM and SEM in the Shanggong orogenic gold deposit. Based on this evidence, we propose a feasible model for the origin of microscopic gold particles in alteration zones. In the early stage of ore-forming fluid, gold may migrate in the form of collaurum, which is maintained by supercritical CO2 and colloidal silica. Low salinity and high pressure are conducive to the stable migration of colloidal gold. When the physicochemical conditions change, some collaurum is precipitated and adsorbed by the clay minerals produced by hydrothermal alteration, and some collaurum undergoes growth and evolves into micro-submicrometer-sized gold particles. This study highlighted the significance of collaurum in the formation of orogenic gold deposits. [ABSTRACT FROM AUTHOR]

A new TLC–densitometric method has been developed for the identification and quantification of paracetamol (PA), propyphenazone (PP) and caffeine (C) in Saridon tablets using the NP-TLC technique combined with densitometry. This method allows for the simultaneous determination of PA, PP, and C in the same sample. Among all the tested chromatographic conditions, the mixture consisting of chloroform + toluene + ethyl acetate + ethanol + acetic acid (18:18:7.5:5.0:0.3, v/v/v/v/v) and a silica gel 60F254 plate proved to be the most effective for the separation of the three tested active pharmaceutical ingredients (APIs) and substances related to paracetamol. The full validation of the proposed NP-TLC method proved that it is specific, precise, accurate, robust and sensitive. The percentage content in relation to the content declared by the manufacturer was for propyphenazone 99.8%, paracetamol 101.6% and caffeine 100.8%, which was in accordance with pharmacopoeial requirements. The results presented indicate the possibility of using the developed method in the routine control of pharmaceutical preparations containing these APIs. The proposed method is economical and more sensitive compared to the previously proposed planar methods for the simultaneous determination of APIs. What is more, the presented method may be an excellent economical alternative when the HPLC method is unavailable for such a determination. [ABSTRACT FROM AUTHOR]

Elastic pressure sensors play a crucial role in the digital economy, such as in health care systems and human–machine interfacing. However, the low sensitivity of these sensors restricts their further development and wider application prospects. This issue can be resolved by introducing microstructures in flexible pressure-sensitive materials as a common method to improve their sensitivity. However, complex processes limit such strategies. Herein, a cost-effective and simple process was developed for manufacturing surface microstructures of flexible pressure-sensitive films. The strategy involved the combination of MXene–single-walled carbon nanotubes (SWCNT) with mass-produced Polydimethylsiloxane (PDMS) microspheres to form advanced microstructures. Next, the conductive silica gel films with pitted microstructures were obtained through a 3D-printed mold as flexible electrodes, and assembled into flexible resistive pressure sensors. The sensor exhibited a sensitivity reaching 2.6 kPa−1 with a short response time of 56 ms and a detection limit of 5.1 Pa. The sensor also displayed good cyclic stability and time stability, offering promising features for human health monitoring applications. [ABSTRACT FROM AUTHOR]

A naked eye and fluorescence turn-on 1,8-naphtahlimide based chemosensor,1, possessing Schiff base linkage was utilized for the rapid detection of highly toxic triphosgene. The proposed sensor selectively detected triphosgene over various other competitive analytes including phosgene with the detection limit of 6.15 and 1.15 µM measured using UV-vis and fluorescence spectrophotometric techniques, respectively. Colorimetric changes observed in solution phase were processed by image analysis using smartphone leading to on-site and inexpensive determination of triphosgene. Further, solid phase sensing of triphosgene was carried out by 1 loaded PEG membranes and silica gel. [ABSTRACT FROM AUTHOR]

A quantitative high‐performance thin‐layer chromatography method has been developed for the estimation of three markers gallic acid, quercetin, and ursolic acid in the extracts and combined formulation of Emblica officinalis, Punica granatum Linn, and Ocimum sanctum Linn extracts. Chromatographic development was performed using precoated silica gel 60 F254 TLC plate and final optimized mobile phase as toluene:ethyl acetate:formic acid (4.5:3:0.2 v/v/v), resulting in optimum resolution with Rf of 0.29, 0.51, and 0.78 for gallic acid, quercetin, and ursolic acid, respectively. Gallic acid and quercetin were detected at 258 nm and ursolic acid at 529 nm after derivatization. All markers showed a good correlation coefficient of 0.9950 for gallic acid, 0.9953 for quercetin, and 0.9945 for ursolic acid. The accuracy and precision measured were less than 2% relative standard deviation for all markers. The mean percent recovery found for gallic acid, quercetin, and ursolic acid were within acceptable limits in formulation indicating that the excipients present have no interference. The proposed method was found to be specific, accurate, linear, precise, and robust, and can be applicable for the simultaneous estimation of gallic acid, quercetin, and ursolic acid for the analysis of individual plant extracts and herbal formulation. [ABSTRACT FROM AUTHOR]

The current study aims to develop and validate an analytical quality by design approach‐based high‐performance thin‐layer chromatographic (HPTLC) method for the analysis of Axitinib tablet samples. The chromatographic conditions in the TLC method were optimized using a three‐level full factorial design. The mobile phase composition and chamber saturation time served as the independent variables for optimization. The mobile phase used for TLC separation on pre‐coated aluminum plates with silica gel 60 F254 consisted of a mixture of ethyl acetate and isopropyl alcohol in a ratio of 9:1 (v/v). Axitinib was quantified at 330 nm using the densitometric method. Axitinib peak from tablet formulation was verified against the reference standard by comparing its single band at Rf 0.44 ± 0.02. Linearity was found to exist between 100 and 600 ng/band, with a correlation coefficient (r2) of 0.9978. The percentage recovery was obtained as 98.21%–99.05%. The system was validated by determining the parameters according to the guidelines of the International Council for Harmonization of Technical Conditions for Medical Products for Human Use. The proposed TLC method can be effectively applied to routine quality control of a pharmaceutical product. [ABSTRACT FROM AUTHOR]

Summary: Inhibition of α‐glucosidases is recognised as an effective approach towards managing postprandial hyperglycaemia. This study aimed to identify a specific compound in Carya cathayensis Sarg. kernels (CCSKs) exhibiting strong inhibitory activities against α‐glucosidase and elucidate the inhibitory kinetic mechanism. Employing a bioassay‐guided approach, an α‐glucosidase inhibitor was isolated from CCSKs through sequential chromatography protocol involving AB‐8 macroporous adsorptive resin, Sephadex LH‐20 and C18‐reversed phase silica gel. The resulting inhibitor was a novel tannin compound, identified as rugosin C ethyl ester. Rugosin C ethyl ester displayed superior inhibitory activity (IC50 of 2.60 μg/mL) compared to acarbose (IC50 of 105.95 μg/mL). The kinetic analysis indicated that rugosin C ethyl ester had a mixed‐type reversible inhibition against α‐glucosidase. The inhibition constants (Ki and Kis) were determined to be 3.119 and 0.856 μg/mL, respectively. The findings indicated that rugosin C ethyl ester might serve as a promising functional ingredient in low‐glycemic index foods. [ABSTRACT FROM AUTHOR]

With the increasing demand for self-adaptive electronics, stretchable and conformable sensors with high sensitivity, stretchability, and self-adhesive are significant intelligent devices. Here a novel tactile sensor is demonstrated that maintains conformal contact to the object for efficient movement monitoring. The device, which was composed of the "H" well-manicured thermoplastic elastomer (TPE), a rectangular polyvinylidene fluoride (PVDF) film coupled with a silver electrode and clamped into the copper-clad signal line ends, and a "U" shaped super-elastic silica gel layer, provided satisfactory performance. The device was investigated as a dynamic monitoring sensor due to its stretchable and conformal configuration. The mechanical stability and high sensitivity suggested that, when attached to the skin of participants, the sensor detected motion induced strain which was experimentally demonstrated. The results show that the novel biomimetic sensor is effective in monitoring human dynamics, with an accuracy exceeding than 98.3%. The stretchable and conformable sensor is low-cost and nontoxic with potential applications in clinical, conformal detection, and artificial intelligence. [ABSTRACT FROM AUTHOR]

Silica aerogels possess extremely low thermal conductivity, low density and high porosity, which can be regarded as candidates for new thermal insulation materials. However, silica aerogels suffer from low strength, brittleness, modeling difficulties and high moisture absorption. In this work, compatible inorganic silica nanowires are introduced as one-dimensional reinforcing materials, and silica nanowires-reinforced silica aerogels (SiO 2 NWs-MSAs) are synthesized using a two-step acid-base catalytic in-situ sol-gel method combined with atmospheric pressure drying, aiming to improve the comprehensive performances of the composite aerogels. The composite aerogels exhibit good mechanical properties, and the composite aerogel has a compressive strength of 1.379 MPa at a strain of 60 % when the doping amount of silica nanowires is 11 %. The volumetric shrinkage of the composite aerogels varies between 11.58 and 12.81 % and the density ranges from 0.11 to 0.13 g cm−3. SiO 2 NWs-MSA2 has a low thermal conductivity and good high-temperature insulation properties with thermal conductivity of 0.039 W m−1 K−1 at 25 °C and 0.046 W m−1 K−1 at 150 °C. The thermal stability of the composite aerogels is improved, and the thermal decomposition temperature reaches 500 °C. Meanwhile, the water contact angles of the composite aerogels all exceed 140°. In addition, the composite aerogels can maintain the amorphous state at 1200 °C, and the microstructure remains basically unchanged at 1000 °C, showing excellent high-temperature resistance. [Display omitted] • A series of SiO 2 NWs-MSAs were prepared by the sol-gel approach. • SiO 2 NWs-MSAs possess low bulk density of 0.11–0.13 g cm−3. • The thermal decomposition temperatures of SiO 2 NWs-MSAs are above 500 °C. • SiO 2 NWs-MSAs exhibit no brittle fracture at strains up to 60 %. • Morphology and chemical structure of SiO 2 NWs-MSAs keep no change after calcination. [ABSTRACT FROM AUTHOR]

Pollen viability, dispersion ability and longevity during deep-freezer storage were studied in three Juniperus taxa distributed in Slovakia. All these characteristics of pollen are closely related to the pollination and/or fertilization success of the junipers in nature. Pollen viability varied considerably between the three populations of J. communis and one population of each, J. sibirica and J. communis var. intermedia. Pollen germination rate ranged between 40.75% and 75.06%, and pollen tube length between 30.32 and 40.41 µm. A clear tendency indicates a higher germination rate of J. communis pollen from lower altitudes and reduced germination of J. sibirica and J. communis var. intermedia pollen from higher altitudes. The dispersion potential of the J. communis pollen during its shedding seems relatively low. In 2021, pollen cloud density was diluted at 68.1% at the 4 m distance from the test shrub, in 2022 of 52.1% at the 17 m distance from the pollen source. A deep-freezer storage of juniper pollen in a double-walled polyethylene bag with silica gel was not efficient enough, as indicated by the drop of pollen germination rate of 31.2% in J. communis and of 79.4% in J. sibirica during a 1-year storage period at − 81 °C. [ABSTRACT FROM AUTHOR]

Several N‐ethoxycarbonylmethyl enaminones, prepared by Eschenmoser sulfide contraction between N‐(ethoxycarbonylmethyl)pyrrolidine‐2‐thione and various ortho‐oxygenated phenacyl halides, underwent cyclisation to give ethyl 6‐aryl‐2,3‐dihydro‐1H‐pyrrolizine‐5‐carboxylates upon microwave heating with silica gel in xylene. With enaminones made from ortho‐hydroxyphenacyl halides, not only did dihydropyrrolizine formation take place, but spontaneous lactonisation also occurred to give 9,10‐dihydrochromeno[4,3‐b]pyrrolizin‐6(8H)‐ones. Bromination and Suzuki‐Miyaura arylation of these chromenopyrrolizines at the free C−H site on the pyrrole ring afforded four analogues of the lamellarin alkaloids in which a pyrrolidine ring replaces the isoquinoline system in the fused polycyclic core. The product 11‐(3,4‐dimethoxyphenyl)‐2,3‐dimethoxy‐9,10‐dihydrochromeno[4,3‐b]pyrrolizin‐6(8H)‐one, in particular, is a congener of the well‐known lamellarin G trimethyl ether. Preliminary results pertaining to an extension to chromenone‐fused indolizines are also reported. [ABSTRACT FROM AUTHOR]