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Silver-indium-sulfide quantum dots (AIS QDs) have potential applications in many areas, including biomedicine. Their lack of regulated heavy metals, unlike many commercialized QDs, stands out as an advantage, but the necessity for alloyed or core-shell structures and related costly and sophisticated processes for the production of stable and high quantum yield aqueous AIS QDs are the current challenges. The present study demonstrates the one-step aqueous synthesis of simple AgInS2 QD compositions utilizing for the first time either a polyethyleneimine/2-mercaptopropionic acid (AIS-PEI/2MPA) mixture or only 2-mercaptopropionic acid (AIS-2MPA) as the stabilizing molecules, providing a AgInS2 portfolio consisting of cationic and anionic AIS QDs, respectively, and tuneable emission. Small AIS QDs with long-term stability and high quantum yields (19-23%) were achieved at a molar ratio of Ag/In/S 1/10/10 in water without any dopant or a semiconductor shell. The theranostic potential of these cationic and anionic AIS QDs was also evaluated in vitro. Non-toxic doses were determined, and fluorescence imaging potential was demonstrated. More importantly, these QDs were electrostatically loaded with zwitterionic 5-aminolevulinic acid (ALA) as a prodrug to enhance the tumor availability of ALA and to improve ALA-induced porphyrin photodynamic therapy (PDT). This is the first study investigating the influence of nanoparticle charge on ALA binding, release, and therapeutic efficacy. Surface charge was found to be more critical in cellular internalization and dark toxicity rather than drug loading and release. Both QDs provided enhanced ALA release at acidic pH but protected the prodrug at physiological pH, which is critical for tumor delivery of ALA, which suffers from low bioavailability. The PDT efficacy of the ALA-loaded AIS QDs was tested in 2D monolayers and 3D constructs of HT29 and SW480 human colon adenocarcinoma cancer cell lines. The incorporation of ALA delivery by the AIS QDs, which on their own do not cause phototoxicity, elicited significant cell death due to enhanced light-induced ROS generation and apoptotic/necrotic cell death, reducing the IC50 for ALA dramatically to about 0.1 and 0.01 mM in anionic and cationic AIS QDs, respectively. Combined with simple synthetic methods, the strong intracellular photoluminescence of AIS QDs, good biocompatibility of especially the anionic AIS QDs, and the ability to act as drug carriers for effective PDT signify that the AIS QDs, in particular AIS-2MPA, are highly promising theranostic QDs., Newton-Katip Celebi Fund partnership; Research Councils UK; Scientific and Technological Research Council of Turkey (TÜBİTAK)

Nano size ZrC powder was prepared by liquid polymeric precursor method. Zirconium n-butoxide (Zr(OnBu)4) and benzoylacetone (BA) were mixed directly with different molar ratios to synthesize transparent liquid zirconium carbide single-source precursors. The carbon content in the precursor could be changed by adding different amount of BA. X-ray pure ZrC was obtained when the molar ratio of BA/Zr(OnBu)4 was 4.6:1. The viscosity of the precursor was very low (

Silver nanowires (AgNWs) based electrode are the potential candidates to replace expensive ITO electrodes in the next generation of flexible electronics. Herein, AgNWs of ∼1000 aspect ratio were synthesised by using simple and cost-effective salt mediated polyol synthesis method. The AgNWs based transparent conducting electrodes (TCEs) have demonstrated the transparency and sheet resistance of 81% and 20 Ω/sq. The effect of AgNO3 injection rate, PVP/AgNO3 molar ratio, and NaCl/KBr ratio on the AgNWs morphology was extensively studied and optimized to 0.2 mL/min, 4.5:1 and 3.8:1, respectively. The effect of post annealing on TCE has also been studied and optimized to 150 °C.

The design of conducting organic metal chalcogenides (OMCs) has attracted extensive attention for their applications in diverse areas. However, only a handful of OMCs exhibit appealing electrical transport properties due to the limited synthetic approaches. Herein, a facile and controllable synthetic approach for the preparation of highly crystalline benzenehexathiol (BHT)-based OMCs using Cu2O as a precursor is reported. Under heterogeneous conditions, a series of highly conducting organic metal chalcogenides CuxBHT (x = 3, 4, and 5.5) were precisely constructed via variation of the molar ratio between Cu2O and BHT. In particular, a fascinating chemical transformation phenomenon was discovered in this work. This is the first time that a phase transition has been observed in conducting OMCs, with the semiconducting species (Cu4BHT and Cu5.5BHT) being converted to metallic species (Cu3BHT) under delicate oxidation regulation. This work provides a prominent paradigm for constructing highly crystalline OMCs, and opens up the possibility of developing OMCs with different structural topologies through chemical transformation.

Blast furnace slag (BFS), as a byproduct from manufacturing iron, served as a cost-effective raw material for preparation of hydroxyapatite-zeolite composite material (HAP-ZE); this research introduces a way of synthesizing hydroxyapatite-zeolite composite material (HAP-ZE) using BFS with alkaline fusion and hydrothermal treatment. According to analysis with XRD, FT-IR, BET, ICP, FE-SEM, EDX and elemental mapping, the major phases in the HAP-ZE composite material synthesized under the most desirable conditions (at aging time of 6 h and at Ca/P ratio (starting gel) = 1.67) were identified to be zeolite and HAP with molar ratio of Ca/P = 1.61, Si/Al = 1.31, Na/Al = 1.75 and with a mean surface area of 44.22 m2.g−1. Moreover, the research found that the minor metals (Mg, Fe, K, etc.) generated from BFS have little influence on the synthesis of HAP-ZE. The thus obtained HAP-ZE material has a great adsorption performance in removing Mn2+, NH4+ and phosphate ions mixed in water, on grounds of the higher ion-exchange capacities and abundantly existing Ca2+ ions in HAP-ZE structure. This novel process makes synthesizing HAP-ZE composite material from BFS possible and lays a great foundation for effective application of BFS.

Anti-Aβ therapy has dominated clinical trials for the prevention and treatment of Alzheimer's disease (AD). However, suppressing Aβ aggregation and disintegrating mature fibrils simultaneously remains a great challenge. In this work, we developed a new strategy using a charged tubular supramolecule (CTS) with pillar[5]arene as the backbone and modifying amino and carboxyl groups at the tubular terminals (noted as CTS-A, CTS-A/C, and CTS-C, respectively) to suppress Aβ fibrillation for the first time. According to the spectroscopic and microscopic characterizations, Aβ40 fibrillation can be efficiently suppressed by CTS-A in a very low inhibitor:peptide (I:P) molar ratio (1:10). A greatly alleviated cytotoxic effect of Aβ peptides after the inhibition or disaggregation process is further disclosed. The well-organized supramolecular structure drives multivalent interaction and gains enhanced efficiency on amyloid fibrillar modulation. These results open a new path for the design of supramolecules in the application of AD treatment.

Biofortified foods are a new approach to increase minerals in the diet, and evidence suggests that zinc (Zn) biofortification can improve Zn physiological status in humans. This systematic review aimed to answer the question: "What are the effects of the consumption of Zn biofortified foods on Zn status in humans?". This review was conducted according to PRISMA guidelines and registered in PROSPERO (CRD42021250566). PubMed, Cochrane, Scopus and Science Direct databases were searched for studies that evaluated the effects of Zn biofortified foods on Zn absorption. Of 4282 articles identified, nine remained after inclusion/exclusion criteria were applied. Limitations in study quality, external and internal validity (bias/confounding), and study power were evaluated. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was used to assess the certainty of evidence. Of the nine articles included, five observed an increase in total Zn absorption, and one showed that Zn participated in the conversion of linoleic acid to dihomo-γ-linolenic acid. By increasing the amount of Zn in the food, Zn biofortification can reduce the phytate:Zn molar ratio and improve Zn absorption in humans. More studies are needed to clarify what portion of Zn biofortified foods/day is needed to achieve a significant effect on Zn status.

Coagulation and precipitation is a widely applied method to remove F− from wastewater. In this work, the effect of coagulation on the removal of F− and organic matter from coking wastewater was studied using AlCl3 and FeCl3 as compound coagulants. The removal rates of F− and organic matter under different coagulant doses and pH conditions were investigated. The results show that the highest removal rates of F− by AlCl3 and FeCl3 are 94.4% and 25.4%, respectively; when the dosage is 10 mmol/L, the TOC removal rates of FeCl3 and AlCl3 reach 20.4% and 34.7%, respectively. Therefore, the removal rate of F− by AlCl3 is higher than that of FeCl3, but the removal rate of organic matter by FeCl3 is relatively higher. The addition of Ca2+ can promote the removal of F−, but the removal rate of organic matter decreases. In addition, by investigating the effects of different pH and Fe–Al ratio on the removal rate, the removal effect of adding FeCl3 and AlCl3 at the same time was discussed. The results show that the most suitable working condition for the removal of organic matter and F− is that the pH is 6.5 and the molar ratio of Al/Fe is 8:2. Overall, the removal mechanism of F− and organic matter in coking wastewater by FeCl3 and AlCl3 was explored in this study. The experimental results can provide reference for the advanced treatment of coking wastewater.

Effective cocrystallization technology plays a significant role in regulating the properties of existing explosives. A new energetic cocrystal consisting of TNB and TNCB in a 1:1 molar ratio was sy...

We report the synthesis of hyperbranched organic microwire (MW) networks comprising 1,4-bis(pentafluorostyryl)benzene (10Ft) and 9,10-bis(phenylethynyl)anthracene (BA) using a simple solution co-assembly route. Pure 10Ft or BA assemblies cannot produce such complex MW networks; in contrast with a binary cocrystal of 10Ft and BA with a 2:1 molar ratio ((2:1)10Ft:BA), which is formed via intermolecular arene-perfluoroarene (AP) interactions. A new generation of multiple MWs grow epitaxially on the previous generation of MWs to form MW arrays in which BA may also act as an intermediate product to facilitate the regeneration of (2:1)10Ft:BA. Highly aligned and well-connected MW networks enable superior optical waveguiding ability. Moreover, a red-emitting dopant, 5,12-bis(phenylethynyl)naphthacene (BN) was incorporated into (2:1)10Ft:BA host MWs, giving light-harvesting hierarchical MW networks via an energy-transfer (ET) process. The realization of the hyperbranched MWs provides us with deep insight into the rational creation of complex branched arrays from functional organic cocrystals.

Herein we systematically investigated the coordination assembly behavior of Zr4L6 cages with Eu3+ ions at room temperature. Through adjustment of the concentration of Eu salt and changes of the type and molar ratio of the solvent, a series of Zr4L6-Eu structures with different structure dimensionalities have been synthesized and structurally characterized. In addition, we also studied the optical properties of these materials in detail, including the fluorescent and third-order nonlinear-optical properties. Most notably, a 2D layer structure with a strong aromatic π···π-stacking force exhibits a good optical-limiting effect.

Compositional modification engineering was designed to simultaneously reduce the sintering temperature and improve the dielectric properties of BaTa2V2O11 via in-situ adjusting the V5+/Ta5+ molar ratio. A series of BaTa2-xV2+xO11 ceramics, fabricated by a solid-state reaction method, were characterized for structural evolution and dielectric properties variations. In-situ adjusting V5+/Ta5+ molar ratio significantly lowered the sintering temperature of BaTa2V2O11 and prominently improved the temperature stability of resonance frequency which is explained by the dielectric dilution theory. Competitive microwave dielectric properties with er = 11.5–25.9, Q × f = 22,172–42,660 GHz, and τf = 42.4–74.6 ppm/oC were achieved in the BaTa2-xV2+xO11 ceramics sintered at 620–840 oC. All the results indicate that the molar ratio of V5+ is primarily responsible for improving the densification behavior and dielectric characteristics of BaTa2-xV2+xO11, which in turn increases the appropriateness in further practical applications.

A series of silver sulfide composites were prepared via the hydrothermal method with l-cysteine and AgNO3 in water at a range of l-cysteine/AgNO3 molar ratio of 0.5–8. The prepared Ag/AgxS material...

During a recent biodiscovery study to identify new α-synuclein (α-syn) aggregation inhibitors, we screened 29 Australian marine sponge and ascidian extracts in an MS binding assay. This resulted in an extract from the ascidian Sycozoa cerebriformis showing activity toward α-syn. The bioassay and MS guided isolation process led to the identification of one new polyoxygenated sterol sulfate, sycosterol A (1). The structure of this low-yielding steroid was elucidated from HRMS and NMR analysis. Sycosterol A displayed moderate antiaggregation activity with 46.2% (±1.8) inhibition when screened against α-syn at a 5:1 (sycosterol A:α-syn) molar ratio. The α-syn antiaggregation activity displayed by 1 and the recent discovery of similar sterols with α-syn antiaggregation activity and potent antiprion activity suggest this unique class may be useful antineurodegenerative compounds.

Highly efficient enrichment of phosphopeptides is of great significance for phosphoproteomics-related biological and pathological processes research, but it remains challenging due to the lack of affinity materials which hold high enrichment efficiency and capacity. Ti3C2Tx MXene, a novel two-dimensional material with outstanding physicochemical properties, has attracted wide research interests for application in various fields. However, there are few reports on the use of MXene-derived materials for phosphopeptides separation in the biomedical field. In this work, we proposed a facile one-pot method that in situ oxidation and modification of Ti3C2Tx MXene, to prepare two-dimensional (2D) magnetic Fe3O4/TiO2@Ti3C2Tx composites for potential application in phosphopeptides enrichment. Benefiting from the outstanding magnetic responsiveness and multiaffinity sites (Ti-O, Fe-O, and NH2 groups), the Fe3O4/TiO2@Ti3C2Tx composites possessed excellent enrichment performance with high sensitivity (0.1 fmol μL-1), excellent selectivity (β-casein: bovine serum albumin = 1:5000, molar ratio), good repeatability (5 times), and high enrichment capacity (200 mg g-1). Moreover, the results of selective enrichment of phosphopeptides from nonfat milk, human saliva, human serum, and rat brain lysates indicated the great potential of Fe3O4/TiO2@Ti3C2Tx composites in low-abundance phosphopeptides enrichment from complex biological samples. This work has put forward a versatile method to prepare magnetic MXene composites and promoted the use of MXene composites in phosphoproteome in biomedicine.

Although many researchers have made great efforts to pursue promising high-efficiency electrocatalysts, a formidable challenge remains for designing excellent palladium-based electrocatalysts for commercializing direct liquid fuel cells. This study reports the synthesis of bimetallic PdPb nanoparticles (NPs) via a mixed solution containing cetyl trimethyl ammonium bromide as the capping agent. Alloyed PdPb NPs are formed, where the size of the NPs increases as Pb atoms are introduced gradually. However, Pd3Pb NPs are obtained with the same molar ratio of Pd and Pb in the raw systems. Among all of the as-made NPs, Pd9Pb1 NPs exhibit superior catalytic activity (2620 mA mg-1) toward ethanol electrooxidation, 4.3 times higher than commercial Pd/C catalysts (613 mA mg-1). The overall rate of the EOR for PdPb NPs is determined, demonstrating that the electrocatalytic activity of the PdPb NPs increases at high catalytic temperatures, in high pH environments, and/or at high ethanol concentrations.

In this study, photocatalytic degradability of Floxin antibiotic by UV/ZnO/sulfite (UZS) advanced oxidation process was evaluated. The degradation rate of Floxin antibiotic by UV/ZnO (UZ) and UV alone processes were 30% and 15%, respectively, within 5 min. It was observed sulfite has a synergistic effect on the performance of UZ, as the complete destruction of Floxin was achieved when sulfite was introduced into the photocatalytic medium. The complete degradation of Floxin by UZS was obtained at pH of 12.0, sulfite/ZnO molar ratio of 1:3 after 5 min of reaction. According to kinetic studies, the observed rate of Floxin degradation (robs (mg L-1 min)) by UZS was 63 and 25 times that of UV alone and UZS, respectively. The values of energy consumption and the total cost for UV alone, UZ and UZS processes were estimated to be (50 kWh m-3 and 1.4 $ m-3), (20 kWh m-3 and 0.98 $ m-3) and (0.78 kWh m-3 and 0.82 $ m-3), respectively.

A new series of azo chromene dyes were synthesized via a facile cyclocondensation reaction of (E)-1,2-diphenyl-1-diazene and 4-aminocoumarin with 1:2 molar ratio catalyzed by the polyaniline-Fe3O4@ZnO nanocomposite (PANI-Fe3O4@ZnO). The salient features of this protocol lie in simple experimental procedure, moderate reaction conditions, and uses PANI-Fe3O4@ZnO nanocomposite as a magnetically separable heterogeneous catalyst. Two well-known methods were employed for assessing the antioxidant abilities of the target compounds, including free radical trapping of 2,2-diphenyl-1-picrylhydrazyl (DPPH), as well as ferric reducing antioxidant power assay. Also, several synthesized compounds were screened for their in vitro antimicrobial activities by employing the disk diffusion test on Gram-negative as well as Gram-positive bacteria.

Lipid nanoparticles (LNPs) for the efficient delivery of drugs need to be designed for the particular administration route and type of drug. Here we report the design of LNPs for the efficient delivery of therapeutic RNAs to the lung via nebulization. We optimized the composition, molar ratios and structure of LNPs made of lipids, neutral or cationic helper lipids and poly(ethylene glycol) (PEG) by evaluating the performance of LNPs belonging to six clusters occupying extremes in chemical space, and then pooling the lead clusters and expanding their diversity. We found that a low (high) molar ratio of PEG improves the performance of LNPs with neutral (cationic) helper lipids, an identified and optimal LNP for low-dose messenger RNA delivery. Nebulized delivery of an mRNA encoding a broadly neutralizing antibody targeting haemagglutinin via the optimized LNP protected mice from a lethal challenge of the H1N1 subtype of influenza A virus, and delivered mRNA more efficiently than LNPs previously optimized for systemic delivery. A cluster approach to LNP design may facilitate the optimization of LNPs for other administration routes and therapeutics. Lipid nanoparticles can be optimized for the efficient delivery of therapeutic mRNAs to the lung via nebulization, as shown for the delivery of a therapeutic antibody in mice challenged with a lethal dose of the H1N1 influenza A virus.

A colorimetric assay based on the oriented TA-AuNPs-PEG-FITC for rapid and sensitive PABA detection was proposed. Initially, the negatively charged TA modified on the surface of AuNPs enabled rapid binding to PABA due to the electrostatic interaction and hydrogen bond, resulting in a visible color change. However, particles were aggregated in a non-oriented way, leading to an unstable testing system which failed to realize the accurate quantification. Thus, the asymmetrically functionalized TA-AuNPs-PEG-FITC were prepared, in which the stabilizer agent of HS-PEG-FITC was attached to the specific sites on the surface of TA-AuNPs. Such a way of modification resulted in an oriented aggregation manner, the addition of PABA induced the formation of oligomers. Moreover, the introduction of FITC group acted as fluorescent marker, providing a simple, fast and quantitative method for characterization of PEG chain. The molar ratio between TA-AuNPs and modified PEG-FITC was further determined. A linear regression was established in a wide range from 10 μM to 1 mM with the LOD of 6.9 μM. Finally, the sensor was successfully applied in the health food. This was the first example in which TA-AuNPs-PEG-FITC were fabricated for colorimetric detection of PABA, and an indirect method based on fluorescence marker was well used to quantify the content of PEG chain.

A binuclear complex of palladium (Et3NH)2[Pd2(ca)2(μ-Cl)2]·2CH3CN is synthesized by ligand-exchange reaction between [PdCl2(PhCN)2] and (Et3NH)2ca (ca2– = chloranilate) taken in a 1:1 molar ratio. Its crystal structure is determined. Chloranilate ca2– dianion is coordinated to Pd(II) as C-donor bidentate ligand. Using cyclic voltammetry (CV) of the complex in CH3CN, non-reversible oxidation at Ea = 1.58 V and quasi-reversible reduction with Eb = –0.80 V and Ea = –0.54 V (relative to Ag/AgCl) is found. The electron structure of the complex is examined.

Developing an effective and durable antibacterial surface is important for surgical tools and biomedical implants. In this work, a zwitterionic copolymer containing catechol groups as biomimetic anchoring segments was coated onto 316 L stainless steel via drop-casting. Energy-dispersive X-ray spectroscopy (EDS) and water contact angle (WCA) measurements indicated that the coatings made of the copolymers containing zwitterionic and dopamine segments at the molar ratios of 8:2 and 6:4 exhibited stronger stability and mechanical durability than the one at 9:1 after inducing tape-peeling and ultrasonication damage. The mechanically durable nanocoatings exhibited excellent antibacterial performance against Staphylococcus aureus and Escherichia coli in a period of 3 days. The nanocoatings with zwitterionic and dopamine segments at the molar ratio of 8:2 were further evaluated and demonstrated durable antibacterial performance after tape-peeling and ultrasonication treatments.

The molar ratio variations of organic and inorganic reactants of chloridobismuthates(III) with N,N-dimethylethane-1,2-diammonium, [(CH3)2NH(CH2)2NH3]2+, and N,N,N′,N′-tetramethylguanidinium, [NH2C{N(CH3)2}2]+, cations lead to the formation of four different products, namely, tris(N,N-dimethylethane-1,2-diammonium) bis[hexachloridobismuthate(III)], [(CH3)2NH(CH2)2NH3]3[BiCl6]2 (1), catena-poly[N,N-dimethylethane-1,2-diammonium [[tetrachloridobismuthate(III)]-μ-chlorido]], {[(CH3)2NH(CH2)2NH3][BiCl5]} n (2), tris(N,N,N′,N′-tetramethylguanidinium) tri-μ-chlorido-bis[trichloridobismuthate(III)], [NH2C{N(CH3)2}2]3[Bi2Cl9] (3), and catena-poly[N,N,N′,N′-tetramethylguanidinium [[dichloridobismuthate(III)]-di-μ-chlorido]], {[NH2C{N(CH3)2}2][BiCl4]} n (4). The hybrid crystals 1–4, containing relatively large but different organic cations, are composed of four distinct anionic substructures. They are built up from isolated [BiCl6]3− octahedra in 1, from face-sharing bioctahedral [Bi2Cl9]3− units in 3, from polymeric corner-sharing {[BiCl5]2−} n chains in 2 and from edge-sharing {[BiCl4]−} n chains in 4. The distortions shown by the single [BiCl6]3− polyhedra in 1–4 are associated with intrinsic interactions within the anionic substructures and the organic...inorganic substructures interactions, namely, N/C—H...Cl hydrogen bonds. The first factor is the stronger, which is evident in comparison of the experimentally determined geometrical and calculated distortion parameters for the isolated octahedron in 1 to the more complex inorganic substructures in 2–4. The formation of N—H...Cl hydrogen bonds, in terms of their number and strength, is favoured for 1 and 3 containing relatively easily accessed hydrogen-bond acceptors of isolated [BiCl6]3− and [Bi2Cl9]3− units. The studies of the deviations from regularity of the [BiCl6]3− octahedra within inorganic substructures were supported by a survey of the Cambridge Structural Database, which confirmed the role played by different factors in the variations in geometry of the inorganic anions.

The reaction of tris(2-methoxy-5-chlorophenyl)antimony with pentafluoropropionic, heptafluorobutanoic, pentafluorobenzoic, or 2-methoxybenzoic acids in the presence of hydrogen peroxide (1 : 2 : 1 molar ratio) in diethyl ether has afforded tris(2-methoxy-5-chlorophenyl)antimony dicarboxylates (2-MeO-5-ClC6H3)3Sb[OC(O)R]2, R = C2F5, C3F7, C6F5, or C6H4ОMe-2. Structures of the synthesized compounds have been investigated.

Medium density fibreboards (MDF) are currently not recycled after service life, but various publications report on recycling by the disintegration of MDF using various techniques and the properties of obtained recovered fibres (RF). In this study, the main aim was to put back RF into the MDF manufacturing process as closed-loop recycling using repeated thermo-hydrolytic disintegration. Compared to previous studies, the focus was on the recycling of MDF with a relatively low F:U molar ratio (1.11). Urea–formaldehyde-bonded MDF with a target density of 700 kg m−3 was subjected to thermo-hydrolytic disintegration in an autoclave using only water at 95 °C for 20–30 min. Afterwards, the properties of RF and virgin fibres (VF), of MDF produced thereof and the composition of the disintegration water (DW) were determined. The nitrogen content (NC) revealed that RF contained about 30% of the initially applied UF. The pH of the DW hardly changed during recycling and it contained considerable amounts of reducing sugars. Using RF did not result in higher formaldehyde emissions than VF. Compared to earlier studies using a higher formaldehyde content (higher F:U ratio), MDF bonded with modern UF resins can be disintegrated under clearly milder disintegration conditions with respect to temperature and time. The properties of recycled MDF were similar to those of reference MDF; up to 100% RF could be used without severely deteriorating the strength and increasing formaldehyde emissions from these panels.

The reaction between methylammonium iodide ( $${\text{MAI}}$$ $$({\text{MA}} = {\text{CH}}_{3} {\text{NH}}_{3}^{ + } )$$ ) and antimony sulfoiodide ( $${\text{SbSI}}$$ ) in reflux conditions results in the formation of a 2D-layered perovskite phase, methylammonium antimony iodide ( $${\text{MA}}_{3} {\text{Sb}}_{2} I_{9}$$ ). X-ray diffraction $$\left( {{\text{XRD}}} \right)$$ and $${\text{UV}} - {\text{Vis}}$$ spectroscopy confirm that in reflux conditions, the reaction between $${\text{MAI}}$$ and $${\text{SbSI}}$$ in a 2:7 molar ratio (MR(2:7)) obtains the $$2D$$ -layered $${\text{MA}}_{3} {\text{Sb}}_{2} I_{9}$$ lead-free perovskite phase as the main product. The MR(2:7) $${\text{~MAI}}$$ - $${\text{SbSI}}$$ reaction product in a carbon matrix in lateral electrode configuration exhibits a relatively high difference between light and dark current $$\left( {I_{{{\text{light}}}} - I_{{{\text{dark}}}} } \right)$$ of ~ 55 µA at 1 V applied bias voltage. The better photoresponse for the MR(2:7) $${\text{MAI}}$$ - $${\text{SbSI}}$$ reaction product in the presented device configuration indicates that the lead-free 2D-layered perovskite structure ( $${\text{MA}}_{3} {\text{Sb}}_{2} I_{9}$$ ) found assistance from the carbon materials for improved photogenerated charge carrier harvesting.

Compounds with the general formula $${{{\text{K}}}_{x}}{\text{V}}_{x}^{{{\text{4}} + }}{\text{V}}_{{{\text{2}} - x}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}}{\kern 1pt} \cdot {\kern 1pt} n{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ (0.1 ≤ х ≤ 0.33, 0.2 ≤ n ≤ 0.5) have been synthesized via hydrolytic precipitation using VOSO4·3H2O and HCl. In the presence of hydrated vanadyl sulfate at a KVO3/VOSO4·3H2O molar ratio between 0.1 and 1.0, the process yields $${{{\text{K}}}_{{{\text{0}}{\text{.33}}}}}{\text{V}}_{{{\text{0}}{\text{.33}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.67}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}}{\kern 1pt} \cdot {\kern 1pt} {\text{0}}.2{{{\text{H}}}_{{\text{2}}}}{\text{O}}{\text{,}}$$ having the highest tetravalent vanadium content. The synthesized compounds have been proposed as electrode materials of all-solid-state ion-selective electrodes. The best performance is offered by an electrode with a $${{{\text{K}}}_{{{\text{0}}{\text{.33}}}}}{\text{V}}_{{{\text{0}}{\text{.33}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.67}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}}{\kern 1pt} \cdot {\kern 1pt} {\text{0}}.2{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ based membrane sensitive to potassium cations in the range 1 ≤ $${\text{p}}{{C}_{{{{{\text{K}}}^{ + }}}}}$$ ≤ 4 with a calibration curve slope of 56 mV/ $${\text{p}}{{C}_{{{{{\text{K}}}^{ + }}}}}$$ at 3.6 ≤ рН ≤ 7.0. We have determined the selectivity coefficients of the electrodes for singly, doubly, and triply charged cations.

Reaction of 5,5-dimethyl-3-(2-chloroethyl)- and 5,5-diphenyl-3-(2-bromoethyl)- hydantoins with potassium 4-aminobenzoate in dimethylformamide in the presence of triethylbenzylammonium chloride leads to the formation of 2-[5,5-dimethyl(diphenyl)-2,4-dioxo-1,3-diazolidin-2-yl]ethyl-4-aminobenzoates. The latter were used for synthesis of new types of maleimides, namely 2-[5,5-dimethyl(diphenyl)-2,4-dioxo-1,3-diazolidin-2-yl]ethyl-4-(2,5-dioxo-1-azolin-1-yl) benzoates. Reactions of 5,5-dimethyl-1,3-di(2-chloroethyl) hydantoin with potassium 4-aminobenzoate or sodium 4-N-acetylaminophenolate at a molar ratio of 1:2 also lead to 3-monosubstituted products.

SBA-15 was modified via post-treatment with (NH4)2SiF6 and (NH4)3AlF6 solution (NSF-T and NAF-T) and applied as support of Pd catalysts for the hydrogenation of 2-ethyl-anthraquinone (EAQ). The characterization results revealed that F could be incorporated into the framework of SBA-15 by forming Si–F bond and the amount of F increased as the molar ratio of F in treating solution to Si species in SBA-15 (F/Si) increased from 0.1 to 0.4 for NSF-T and 0.3 to 0.6 for NAF-T. At the same F/Si, the incorporated amount of F was larger with NSF-T than with NAF-T, and the latter could simultaneously create acid sites in catalysts. The hydrophobicity of catalysts could be effectively improved by incorporating F into SBA-15 supports, which favored the catalytic performance. The catalyst on SBA-15 treated by NSF with F/Si of 0.3 exhibited the high initial activity (0.24 molH2·gPd−1·min−1) and selectivity (95.5%).

Extracts of copoazu (Theobroma gramdiflorum), canangucha (Maurita Flexuosa), and coffee (coffea arabica) were explored as enhancers of the solar photo-Fenton process to eliminate acetaminophen, sulfamethoxazole, carbamazepine, and diclofenac. The process performance, at pH 6.2 and 5 mg L− 1 of iron without the extracts, has a very limited action (~ 35% of the pollutants degradation at 90 min of treatment) due to the iron precipitation. Interestingly, the extracts addition increased the soluble iron forms but only copoazu extract improved the pollutants degradation (~ 95% of elimination at 90 min of the process action). The copoazu extract acted as a natural complexing agent, maintaining the soluble iron up to 2 mg L− 1 even after 90 min, and consequently enhancing the pollutants degradation. The effect of copoazu extract dose on the process performance was also assessed, finding that an iron: copoazu extract molar ratio equal to 1:0.16 was the most favorable condition. Then, the process improved by copoazu extract was applied to municipal wastewater. Remarkably, the process led to ~ 90% of total pharmaceuticals degradation at 20 min of treatment. This work evidences the feasibility of amazonian fruits extracts to improve the solar photo-Fenton process to degrade pharmaceuticals in aqueous matrices at near-neutral pH.

The silica sol and potassium hydroxide solution are mixed under certain conditions to form a precursor solution, which is poured into a closed cavity and gelled at 75 °C for 24 h to form potassium silicate gel. The structural evolution, stability, and transmittance of potassium silicate gels with different SiO2/K2O molar ratios were investigated. Raman spectroscopy is applied to analyze the SiO4 tetrahedral network of potassium silicate gel and the polymerization index Ip (A500/A1000) increases linearly with the increase of the molar ratio. The relative fractional area of different species Qn as a function of the molar ratio is described in detail through the deconvolution of band 700–1200 cm−1. A(Q2 + Q3)/A(Q2 + Q3 + Q4) is first employed to characterize the polymerization degree of the SiO4 tetrahedral network, which is proven to be reliable. In addition, the stability of potassium silicate gel is measured indirectly by its deformation over time. The higher the molar ratio, the smaller the deformation and the better the stability. When the molar ratio is >6, excessive silica not only acts as a forming agent to increase the polymerization degree of the SiO4 tetrahedral network, but also acts as a filler added into the potassium silicate gel, causing a rapid decrease in transmittance and a sharp increase in haze.

Vimba bream (Vimba vimba) individuals were collected from the Danube River near Belgrade, from May 2016 to May 2017. Samples of muscle and liver tissue were analyzed for concentrations of 25 elements (macro-, micro-, and toxic elements) using inductively coupled plasma optical emission spectrometry (ICP-OES). For both tissues, the highest concentrations of most elements were observed in late spring/early summer (months of May and June). Majority of statistically significant correlations between elements were positive in both tissues. Contributions of Ca, K, and Mg to human diet were in a similar range. The lowest contribution of all macroelements was observed for Na, while the contribution of Se was well above the recommended dietary allowance for this element. Levels of detected elements were well below MAC values prescribed by national and international regulations. The highest value of Hg liver/muscle index (>1) was observed in August, which could indicate a higher contamination of the sampling location in that month. Se:Hg molar ratio never drops below 1, which could indicate that Hg toxicity is prevented. THQ values showed little variation thought the year and were well below the threshold of 1, with the exception of THQ for Al in May (0.92). This element also strongly affects the hazard index.

Herein we report a method for rapid synthesis of Cr2AlB2 from Cr, Al, and B elemental powders. Effects of Cr/Al/B molar ratio in precursors, temperature, duration and mass ratio of the salt to precursors on Cr2AlB2 formation are investigated. Additionally, the synthesis process of Cr2AlB2 is also discussed. Results show that the temperature plays a key role in the formation of Cr2AlB2. Well crystalline Cr2AlB2 powders are successfully synthesized from 2Cr/2Al/2B precursors and NaCl-KCl molten salt with their mass ratio of 1:1 at 1100 °C within 0.5 h. Cr2AlB2 exhibits nanolaminated structure with plate-like grain morphology. The particle size of the obtained Cr2AlB2 powder is dramatically decreased with the addition of NaCl-KCl molten salt in precursors.

Polysaccharides were extracted by hot water and alkali in sequence from Dolichos lablab L. hull, and further purified by ion-exchange and gel columns. Hot water extracted D. lablab hull polysaccharide (DLHP) was rich in glucuronoxylan and pectin, and alkali extracted polysaccharide (DLHAP) mostly embraced glucuronoxylan. The structures of purified glucuronoxylans from DLHP and DLHAP were mainly analyzed by HPAEC-PAD, methylation combined with GC–MS, NMR and SEC-MALLS. DLHP-1 was identified as acetylated glucuronoxylan containing →4)-β-Xylp-(1→ backbone with substitution at O-2 site by α-GlcpA/4-O-methyl-α-GlcpA. The molar ratio of β-Xylp to α-GlcpA was 6.9:1, and acetylation was mainly at O-3 site of β-Xylp with acetylation degree of 21.5%. DLHP-1 and DLHP-2 had similar physicochemical properties, except for molecular weight (Mw). DLHAP-1 was the non-methylated glucuronoxylan almost without acetylation, and it had the molar ratio of β-Xylp to α-GlcpA of 5.6:1. Besides, DLHP-1 (Mw of 20.0 × 103 g mol−1) adopted semi-flexible chain, while DLHAP-1 (Mw of 15.4 × 103 g mol−1) showed flexible chain. These results provided a structural basis for study on polysaccharides from D. lablab hull, which was benefit for understanding biological activities and developing functional food or pharmaceuticals of D. lablab.

Powders of calcium pyrophosphate Ca2P2O7 of γ- and β-modifications have been obtained using the thermal conversion of brushite CaHPO4⋅2H2O synthesized from phosphoric acid H3PO4 and calcium carbonate CaCO3 at a molar ratio P/Ca = 1.1. The resulting powders can be used to create various functional materials, including biocompatible and bioresorbable materials for the treatment of bone defects.

To improve the performance of low-carbon MgO–C refractories, the Cr3C2-coated flake graphite was synthesized by molten salt method, then the Cr3C2-coated flake graphite was added to low-carbon MgO–C refractories. In this work, the effects of reaction temperature, Cr/C mole ratio, and holding time on the synthesis of Cr3C2-coated flake graphite were studied. Furthermore, the effect of Cr3C2-coated flake graphite on the physical properties of low-carbon MgO–C refractories was evaluated. The results indicated that when the reaction temperature was 950 °C, Cr/C molar ratio was 1/2 and holding time was 3 h, the synthesized Cr3C2-coated flake graphite had fewer surface micropores and the crystallinity of Cr3C2 grains was high. In addition, the Cr3C2-coated flake graphite exhibited excellent oxidation resistance. MgO–C refractories containing 2 wt% Cr3C2-coated flake graphite exhibited more excellent physical properties. The results of nano CT detection system showed that the addition of Cr3C2-coated flake graphite promoted the densification of MgO–C refractories.

In order to prepare carbon nanotubes with high specific surface area, small diameter, low resistivity, high purity and high catalytic activity, the Fe-Mo/Al2O3 catalyst was prepared based on the microreactor. The influence of different Fe/Al molar ratios on the catalyst and the carbon nanotubes prepared was studied through BET, SEM, TEM and other detection methods. Studies have shown that the pore structure of the catalyst is dominated by slit pores at a lower Fe/Al molar ratio. The catalytic activity is the highest when the Fe/Al molar ratio is 1:1, reaching 74.1%. When the Fe/Al molar ratio is 1:2, the catalyst has a higher specific surface area, the maximum pore size is 8.63 nm, and the four-probe resistivity and ash content of the corresponding carbon nanotubes are the lowest. The higher the proportion of aluminum, the higher the specific surface area of the catalyst and the carbon nanotubes, and the finer the diameter of the carbon nanotubes, which gradually tends to relax. The results show that when the Fe/Al molar ratio is 1:2, although the catalytic activity of the catalyst is not the highest, the carbon nanotubes prepared have the best performance.

Montmorillonite-based porous adsorbent prepared by gel casting method was used to adsorb Cr(III)-organic complexes in tanning wastewater,together with the initial concentration of 10 mg L−1. The as-porous adsorbent exhibited an excellent performance of separation. Meanwhile, its structural and morphology were characterized by TG, BET, XRD, SEM, EDS and XPS, showing that the porous adsorbent was complete hollow ball structure. And the adsorption results showed that the adsorption amount of porous adsorbent rapidly declined from 9.58 to 5.28 mg L−1, and only Cr(III) was adsorbed, when the molar ratio of Cr(III) and citrate was more than 1:5. Increased of pH was beneficial to adsorb Cr(III)-citrate in range from 2.46 to 7.12. Furthermore, the best removal efficiency of Cr(III)-organic complex was up to 97% and still above 84% after five cycles with porous adsorbent. Finally, the mechanism on adsorbing Cr(III) with porous adsorbent is also provided. Therefore, a kind of porous adsorbent which was easily separated, was prepared to deeply treat tanning wastewater containing Cr(III)-organic complex, and solve the problem of difficult recycle.

Silica aerogels prepared via microwave irradiation using tetraethyl orthosilicate (TEOS) as the precursor are described. The aerogels were obtained after subjecting the entire process under microwave irradiation, significantly reducing the synthesis time to 90 min, which is much shorter than the supercritical CO2 drying (SCD) method and ambient drying (APD) method. The obtained aerogels under microwave irradiation condition with different power and time exhibit surface areas of 831 m2 g−1, average pore sizes of 8.67–12.7 nm, and contact angles of 146.5°. The aerogels are thermally stable and the thermal conductivity is relatively low at 0.028 W m−1 K−1, when the molar ratio of E value (EtOH /TEOS) is 8. The results demonstrate the efficiency of synthesizing silica aerogels via microwave irradiation in the industry.

A unique phenomenon of TiC–TiO2 reaction at 900 °C is established, forming a quasi-pure phase of abnormal titanium oxycarbide, since it is commonly synthesized at temperatures above 1500 °C. Impurity of Magneli phase (TinO2n-1, 4≤n≤9) is also detected in the product. Thermodynamics analysis indicates that the critical C/O concentration of titanium oxycarbide (x in TiCxO1-x) equilibrated with Magneli phase at 900 °C is around 0.66, typically 0.651 for Ti4O7. The obtained titanium oxycarbide phase contains metal-vacancy in Ti site, as Ti1-yCxO1-x which is reported the first time, differing from stoichiometric vacancy of both Ti site and C/O site in conventional TiCxO1-x. The dominating part of TiC–TiO2 reaction at 900 °C is reaction via solid solution as directly introducing the Ti and O atoms of TiO2 into the FCC structure of TiC, which leads to the formation of metal-vacancy without altering the original lattice size, instead maintaining at the same level of TiC regardless of the variation of corresponding C/O concentration. The obtained maximum concentration of metal-vacancy in Ti1-yCxO1-x is 18%, close to the theoretical capacity of 18.9% which exists when the starting molar ratio of TiC and TiO2 is aiming to the formation of TiC0.651O0.349, as the critical composition equilibrated with Ti4O7. The stability of metal-vacancy in titanium oxycarbide is verified by first-principles calculation in the perspective of energy.

To convert carbohydrates into platform compounds, the deep eutectic solvent (DES) based on choline chloride and urea (molar ratio 1:2) was adopted as a green solvent. The physical properties of den...

Epoxidation of the unsaturated fatty acids (UFA) in Tung oil provides a very interesting opportunity in the research and development of advanced materials. Tung oil is one of non-edible vegetable oils and epoxidized Tung oil (ETO) also provides benefits in terms of renewable and eco-friendly. This research evaluated the influences of acetic acid's molar ratio to UFA and stirring velocity in the epoxidation process of Tung oil. Epoxidation was carried out in a batch reactor using peroxyacetic acid produced in-situ with sulfuric acid as a catalyst. This reaction was run at a temperature of 60 °C and the catalyst concentration of 1.5% (w) for 4 hours, with a periodic 30-minutes sampling time interval. The samples' analyses were iodine value (IV), conversion to oxirane, selectivity, and FTIR spectrometry. The results showed that both the molar ratio of acetic acid to UFA and stirring velocity were directly proportional to the conversion to oxirane, and inversely proportional to the IV. In contrast, the two process variables did not show a definite result that can be interpreted to the selectivity (very fluctuated). The highest conversion (about 57.43%) and the lowest IV (8.3898 g I2/100 g) were obtained at a 1:1 ratio for the reaction times of 150 and 240 minutes, respectively.

1,2-bis(triethoxysilyl)ethane (BTESE)-derived membranes have proven thermal and hydrothermal stability and molecular sieving properties. However, BTESE-derived membranes still have low gas permselectivity due to their loose structure. Herein, we propose a novel strategy of co-polymerization using precursors of both BTESE and 1,2-bis(triethoxysilyl)methane (BTESM) to improve the gas permselectivity of BTESE-derived membranes. BTESM is introduced into BTESE network and the microstructure can be adjusted by different molar ratios of BTESE to BTESM. We find that, as the content of BTESM increase, H2 permeations of BTESE-BTESM membranes remain nearly constant, while the permeations of larger gases (CO2 and N2 etc.) exhibit a greatly decreased. The membrane with a molar ratio of BTESE:BTESM = 3:7 exhibits the highest H2/CO2 (11.3) and H2/N2 (26.8) permselectivity while having a relatively high H2 permeance (1.52 × 10−6 mol m2 s−1⋅Pa−1). Our findings may provide novel insights into preparation of co-polymerization organosilica membranes with excellent H2/CO2 and H2/N2 separation performance.

High-performance production of biosurfactant surfactin is very important for real applications of surfactin but still exhibits significant challenges. In this study, an efficient fermentation process with enhanced cell density is developed to improve the surfactin production by Bacillus subtilis ATCC 21332. The addition of 0.2 mM EDTA–Fe2+ complex resulted in the highest surfactin yield of 5.67 g/L within 3 days, which is 7.8 times higher than that obtained by regular fermentation in the absence of this complex. This significantly improved surfactin production is related to the remarkably increased cell density which was stimulated by the addition of EDTA-Fe2+ complex at molar ratio of 1:1, was significantly better than that obtained by the addition of Fe2+, Fe3+ or EDTA alone. Furthermore, a modified repeated fed-batch fermentation process sustained the high-performance fermentation of surfactin at 1.345 g/L d, and the overall surfactin yield reached 9.414 g/L within a fermentation period of 7 days.

Aldol condensation of furfural and acetone is often used as a model reaction to test acid-base properties of solid catalysts. The present study describes the effect of furfural acidity on the catalytic performance of MgAl mixed oxides. Three furfural sources differing in their acidity were used and compared in aldol condensation at T = 55 °C and acetone to furfural molar ratio of 10. The furfural conversion over MgAl mixed oxides depended on the acidity of the furfural source, and the catalysts were partially consumed for neutralization of acid admixtures present in furfural. Only for some furfurals could the furfural conversion be improved by distilling the as-received furfural prior to the aldol condensation experiments. Moreover, the storage of the freshly distilled furfural during a few days, even in a closed flask and at a dark place, resulted in a substantial decrease in furfural conversion in aldol condensation. The results indicate that the distillation of the as-received furfural is an effective method to control the performance of basic catalysts at comparable reaction conditions only for some furfurals. Furthermore, the storage of the freshly distilled furfural has to be performed with care to avoid its re-oxidation.

2,2-Bis[2-(dimethylamino)-5-methylphenyl]acetic acid, Ar2CHCOOH (1) (Ar = 5-Me-2-Me2NC6H3), was synthesized by the carboxylation of s[2-(dimethylamino)-5-methylphenyl]-methyllithium, [Ar2CH]Li(TMEDA), with gaseous CO2. The reaction of 1 with the cationic bis(alkyl) complex [(Me3SiCH2)2Dy(THF)n][BPh4] (2: 1 molar ratio) unexpectedly afforded the tetracarboxylate complex [Dy(O2CCHAr2)4(Et2NH2)2][BPh4] (3), whereas the trinuclear oxo cluster [Dy3O(O2CHAr2)6(THF)4][BPh4] (4) was prepared from [(o-Me2NC6H4CH2)2-Dy(THF)n][BPh4]. In complex 4, three Dy3+ cations are linked by the μ3-oxo oxygen atom and six bridging μ2-κ1-O:κ1-O’-carboxylate ligands. According to the X-ray diffraction data, NMe2 groups of the diphenylmethanide moiety are not coordinated to Dy3+ cations in complexes 3 and 4.

Cr cation doping in the support of the Ru/CeO2 catalyst with a Cr/Ce molar ratio of 1:9 dramatically improved the CO2 methanation activity at low temperatures, with the turnover frequency value on ...

In order to impart good application performance to locust bean gum (LBG) sizes for polyester yarns, methyl acrylate (MA) and acrylic acid (AA) monomers with a variation in feed molar ratio from 1/9...