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• Hollow Ni-Co BTC nanoplates were prepared by a template- and etching-free method. • The hollow Ni-Co BTC nanoplates show good sensitivity and selectivity to NH 3 vapor. • The hollow 2D structure of Ni-Co BTC led to higher NH 3 sensing performance. • The hollow Ni-Co BTC nanoplates maintain good stability after 6 months of testing. This work reports the template- and etching-free fabrication of hollow bimetallic nickel-cobalt benzenetricarboxylic acid (Ni-Co BTC) hexagonal nanoplates by a polyvinylpyrrolidone (PVP)-assisted approach. The incorporation of PVP can reduce the stacking of these nanoplates along the vertical direction and generate depletion forces between them to reduce aggregation. When employed for the quartz crystal microbalance (QCM) sensing of ammonia (NH 3), the hollow Ni-Co BTC hexagonal nanoplates exhibit 1.6, 3.8, and 7.5 times higher sensitivity to 69.5 ppm of NH 3 than non-hollow Ni-Co BTC nanoplates, Ni-BTC nanobelts, and Co-BTC microrods, respectively, and a low limit of detection (LOD) of 1.53 ppm. Additionally, they show good selectivity to NH 3 in the presence of other interfering compounds and excellent stability with only a very small decrease of 2.86 % in sensitivity after 6 months. The NH 3 adsorption on the hollow Ni-Co BTC hexagonal nanoplates follows a pseudo first-order kinetic model with the adsorption rate being 6.1 and 7.1 times faster than Ni-BTC nanobelts and Co-BTC microrods, respectively. The good sensing performance of the hollow Ni-Co BTC hexagonal nanoplates to NH 3 is attributed to the existence of carboxyl and hydroxyl groups which can provide energetic sites for the chemisorption of NH 3 molecules and the increased adsorption sites provided by the hollow two-dimensional structure and the bimetallic composition of this MOF. [ABSTRACT FROM AUTHOR]

Polyaryletherketones (PAEKs) are a class of ultrahigh performance polymers with outstanding temperature and chemical resistance. Poly(ether ketone ketone) copolymer (Kepstan®) and poly(ether ether ketone) (PEEK) display intrinsic insolubility in nearly all organic solvents. The primary issue for the application of these polymers is their processability which requires a high temperature/pressure-based technique, or the use of harsh and corrosive solvents, like methanesulfonic and sulfuric acid, resulting in sulfonation of the polymer backbone that adversely might affect their chemical stability. In this work, we propose a method to prepare porous Kepstan® and PEEK membranes using N -methyl-2-pyrrolidone (NMP) as solvent at room temperature. It consisted of a modification-regeneration strategy to turn commercial semi-crystalline Kepstan® and PEEK into dithiolane soluble derivatives that allow the fabrication of hollow fiber, flat-sheet, and electrospun nanofibers. The resulting membranes are then regenerated to the solvent-resistant materials. The novel Kepstan® and PEEK hollow fibers exhibited a N,N -dimethylformamide (DMF) permeance of 2.21 and 2.05 L m−2 h−2 bar−1, with more than 90% rejection of Crystal Violet (408 g mol−1) and Methyl Orange (327 g mol−1), respectively. [Display omitted] • Porous PEKK and PEEK hollow fiber membranes spun without strong acids at room temperature. • Solvent and temperature-resistant hollow fibers from commercial PEKK and PEEK. • Effective separation of molecules in the range of 327–408 g mol−1 in dimethylformamide. • Chemical modification-regeneration strategy to promote the polyketone processability. [ABSTRACT FROM AUTHOR]

Abstract: The Schiff bases formed by condensation of S-methyl- and S-benzyldithiocarbazate with 2-pyridinecarboxaldehyde react with zinc(II) and cadmium(II) acetates to form stable metal complexes of general formulas, [Zn(NNS)(CH3COO)]2 and [M(NNS)2] (M=Zn2+, Cd2+; NNS− =anionic forms of the 2-pyridinecarboxaldenhdye Schiff bases of S-methyl- and S-benzyldithiocarbazate, respectively) which have been characterized by a variety of physico-chemical techniques and X-ray crystallographic structure analysis. The complexes, [Zn(NNS)(CH3COO)]2 are acetate anion-bridged centrosymmetric dimers in which each of the Schiff bases is coordinated to the zinc(II) ions as a uninegatively charged NNS tridentate chelating agent coordinating via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom. The acetate anion acts as a bridging bidentate ligand coordinating with the two zinc atoms in a syn–syn manner. Each zinc(II) ion in the dimer adopts an approximately square-pyramidal geometry. The bis-ligand complexes, [M(NNS)2] (M=Zn2+, Cd2+) have distorted octahedral structures in which the two anionic Schiff bases are coordinated to the metal ions meridionally as NNS tridentate chelating agents via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom. Both the mono- and bis-ligand zinc(II) complexes exhibit strong cytotoxic activity against the HELA (human cervical cancer) cell lines. Some of these compounds exhibit stronger cytotoxicity against HELA than the commercially important anticancer drug, Tamoxifen. [Copyright &y& Elsevier]

Abstract: The reaction of phthalaldehyde (1,2-benzenedialdehyde) with S-methyldithiocarbazate does not lead to the formation of the expected open-chain linear Schiff base, phthalaldehyde bis(S-methyldithiocarbazonate) but a cyclic diazine dithiocarbazate is obtained which has been characterized by spectroscopic and X-ray diffraction. However, if the reaction of phthalaldehyde with S-methyldithiocarbazate is carried out in the presence of nickel(II) and zinc(II) acetate salts, stable metal complexes of empirical formula, [M(phthalsme)] (M=Ni, Zn; phthalsme=doubly deprotonated form of the Schiff base, phthalaldehyde bis(S-methyldithiocarbazonate) are obtained. Likewise, the reaction of 4N-methyl-3-thiosemicarbazide with phthaladehyde in the presence of nickel(II) acetate also yields a crystalline nickel(II) complex, [Ni(phthaltsc)] (phthaltsc=doubly deprotonated form of the teradentate phthaladehyde bis(4N-methyl-3-thiosemicarbazone) ligand. The complexes, [Ni(phthalsme)], [Ni(phthaltsc)] and [Zn(phthalsme)(DMF)] have been characterized by a variety of physico-chemical techniques and their structures have been determined by X-ray diffraction. In these complexes, the ligands are coordinated to the metal ion as dinegatively charged tetradentate chelating agents via the two thiolate sulfur atoms and the azomethine nitrogen atoms. The nickel complexes, [Ni(phthalsme)] and [Ni(phthaltsc)] exhibit a distorted square–planar geometry whereas the zinc complex, [Zn(phthalsme)(DMF)] is five-coordinate and square-pyramidal with the dianionic Schiff base occupying the basal plane of the square-pyramid and the oxygen atom of dimethylformamide in the apical coordination site. [Copyright &y& Elsevier]

Ruthenium(II) complex containing cis-[Ru(H2dcbiq)(L)(NCS)2], where H2dcbiq = 4,4'-dicarboxy-2,2'-biquinoline and L = 4,4'- di-tert-butyl-2-2'-dipyridyl coded as SPS-02, was synthesized and fully characterized. This complex showed appreciably broad absorption range. The new complex was used as photosensitizer in nanocrystalline TiO2dye-sensitized solar cell application. cis- [Ru(H2dcbiq)(L)(NCS)2] (SPS-02) achieved efficient sensitization of nanocrystalline TiO2over the whole visible range, extending into the near-IR region (ca. 1000 nm) with superior short-circuit photocurrent density (Js = 9.13 mA cm-2) and conversion efficiency (η = 2.09%) compared with complex cis-[Ru(H2dcbiq)2(NCS)2] (1) under an irradiation of full sunlight (100 mW cm-2). [ABSTRACT FROM AUTHOR]

Abstract: Condensation of di-2-pyridyl ketone with S-methyldithiocarbazate or S-benzyldithiocarbazate yields potentially bridging ligands of the form Py2C; Hdpksme (R=Me; the di-2-pyridyl ketone Schiff base of S-methyldithiocarbazate) and Hdpksbz (R=Bz; the di-2-pyridyl ketone Schiff base of S-benzyldithiocarbazate). Complexation of these ligands with Cu(II) in a 1:1M ratio leads to the formation of dinuclear complexes of the general formula [Cu(NNNS)X]2 (X=Cl−, NO3 −, H2O). X-ray crystallographic structure determinations show that each ligand provides three donor atoms (NNS) in a meridional configuration to one metal, viz. one of the pyridine nitrogen atoms, the azomethine nitrogen atom and the thiolate sulfur, while the nitrogen atom of the second pyridyl group forms a bridge to another copper(II) ion within the dimer. The coordination geometry around each copper(II) ion is approximately square pyramidal, the basal plane of which is composed of one of the pyridine nitrogen atoms, the azomethine nitrogen atom and a chlorido, nitrato or aqua ligand. The apical position of the square pyramid is always occupied by the pyridine nitrogen atom of the second ligand. [Copyright &y& Elsevier]

Research on renewable energy is flourishing, as it promises to reduce costs and deliver clean energy for the future. Water oxidation (WO) is one of the most promising and fascinating research fields, offering environmentally friendly renewable fuel sources. However, to make this a reality, efficient WO electrocatalysts (WOEs) have to be prepared from readily available and cost-effective sources. The catalytic activity of WOEs is directly related to their structure and synthesis process. Thus, researchers have focused on preparing Ni and Co (Ni/Co) oxide WOEs through various thermal treatment processes (TTPs) owing to their simplicity, cost effectiveness, and ability to tune the physicochemical properties of the WOEs. In this review, the effect of TTPs on the catalytic activity of Ni/Co oxide-based WOEs were carefully evaluated. To do so the effect of TTPs on the structure-activity relationship (SAR), their advantages and limitations, and how these methods can be properly optimized for preparing Ni/Co oxide WOEs has been discussed based on published reports. Also, the electrochemical techniques and parameters that are most commonly utilized in determining the catalytic activity of WOEs has been discussed along with a general mechanism for WO at the Ni/Co oxide electrocatalysts. • Thermal treatments (TAs) are promising strategies for preparing highly efficient Ni and Co oxides WO electrocatalysts (ECs). • WO reaction pathway involving Ni and Co oxides ECs is highly influenced by the oxidation states of the metal ions. • Different TA processes can significantly influence the surface morphology and chemical composition of Ni and Co oxides ECs. • Doping of metal ions (Fe, Zn, Ga, etc.) in the Ni and Co oxides ECs can be controlled through optimizing the TA conditions. [ABSTRACT FROM AUTHOR]

• Chemical polymerization-ultrasonication assisted synthesis of PANI_AuNPs composite. • Determining the electron transfer kinetics for BPA oxidation through Butler-Volmer theory, Tafel plot, and convoluted potential sweep voltammetry (CPSV) analysis. • Discussing the corresponding BPA oxidation reaction mechanism. • Wide linear range from the nanomolar to micromolar region (0.003 to 0.064 µM and 0.075 to 45.69 µM), with LOD as low as 0.4 nM. • Studying practical applicability of the sensor for detecting bisphenol A from tap water, bottle water, and beverage samples. In this work, a conducting polymer and nanometal composite electrocatalyst was prepared for the sensitive detection of bisphenol A (BPA) over a wide concentration window. Polyaniline (PANI) was first prepared from aniline through a chemical method, and gold nanoparticles (AuNPs) were embedded with the prepared PANI via ultrasonication to obtain the PANI_AuNPs electrocatalyst. The morphological, chemical, and electrochemical properties of the electrocatalyst were then determined, and BPA oxidation was investigated with the help of electroanalytical techniques to understand the electron-transfer process occurring at the PANI_AuNPs interface. The results showed that BPA was oxidized through a multistep electron-transfer process without any intermediate chemical step, and the rate-determining step was the second electron-transfer step. The oxidation proceeded as a 2e–/2H+ process with an electron-transfer coefficient of ≈0.69. These results indicate that the PANI and AuNPs work synergistically to promote the electron transfer from BPA. The quantitative analysis gave a broad linear range and a low limit of detection of 0.4 nM. The sensor was also tested for the detection of BPA in tap water, bottled water, and a canned beverage for real sample analysis. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The increasing amount of waste tires and construction wastes mounting up on the landfills create a huge concern to environmental stability. Researchers and policymakers are searching for ways to reduce and reuse these waste materials to promote a sustainable construction practice. Thus, incorporating crumb rubber (CR) derived from the waste tire and recycled coarse aggregate (RCA) in concrete production pertains to a sustainable future of the construction industry. This paper investigates the combined influence of RCA, CR, and polypropylene (PP) fiber on the physical and mechanical properties of Fiber Reinforced Rubberized Recycled Concrete (FR3C). Furthermore, the flexural response of reinforced concrete (RC) FR3C beams is investigated. A series of fourteen RC beam specimens measuring 150 mm × 200 mm x 1500 mm (w x d x L) are prepared and tested. Several combinations are designed where the variables are CR content (5% and 10%) and steel ratio (0.59% and 1.60%) with contents of RCA and fiber fixed at 30% and 0.5%, respectively. The results of the experimental study suggest an improvement in the concrete short-term and long-term mechanical properties following the introduction of CR and PP fiber. Concrete beams with 30% RCA, 5% CR and 0.5% PP fiber showed improved flexural capacity, ductility, and toughness. Additionally, analysis demonstrates that the existing codes and design guidelines are inadequate for quantifying the flexural capacity of FR3C beams with different reinforcement ratios. Overall, this research demonstrates a new pathway towards the cleaner production of sustainable concrete. • Fourteen beam specimens (1500 mm long) are tested to investigate the flexural response of FR3C beams. • Evaluation of available design guidelines in predicting the flexural capacity of concrete beams containing CR and PP fiber. • Existing codes under-predict the ultimate moment capacities of the LR beams and tend to overestimate that of the HR beams. • Concrete beams with 30% RCA, 5% CR and 0.5% PP fiber shows good flexural capacity, ductility, and toughness. [ABSTRACT FROM AUTHOR]

The use of sustainable natural sources to fabricate porous carbon materials has garnered significant interest in energy storage. This study proposes a method for synthesizing sulfur-doped porous carbon (S‑carbon) materials via the carbonization of bacterial cellulose (BC) impregnated with sodium lignosulfonate (LS), which functions as a renewable source of both carbon and sulfur, eliminating the need for external activation processes. The carbonization process yielded S‑carbon with a notable sulfur content of 1.4 % and a high specific surface area of 650 m 2 /g. Transmission electron microscopy (TEM) images reveal fibrous carbon structures with mesopores and micropores in the S‑carbon material. Electrochemically, S‑carbon exhibited an impressive specific capacitance of 272.6 F g -1 at a current density of 1 A/g and demonstrated outstanding cycling stability, retaining 86 % of its capacitance after 5000 cycles at a current density of 6 A/g in a 3 M KOH electrolyte. The development of sulfur-doped fibrous carbon from BC-LS offers promising potential as a sustainable electrode material for supercapacitors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The application of environmentally friendly and sustainable catalysts requires efficient and safe preparation methods using cheap and renewable materials. Although many metal nanoparticles (NPs) have low colloidal stability, they are still very effective as catalysts. Using a straightforward method, we developed a bacterial cellulose-glycol chitosan-silver (BC-GCS-Ag) nanocomposite, by introducing both AgNPs and self-crosslinked GCS within the BC network. Self-crosslinking of GCS occurred during the formation of AgNPs by employing the glycol moieties for reduction to produce aldehyde functionalities, thereby forming Schiff's base bonds within the GCS structure. Using GCS, well-defined AgNPs within the BC matrix. The formation of AgNPs and the self-crosslinking of GCS were characterized using UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that spherical AgNPs with a mean diameter of 10 nm exhibited a well-organized structure within the BC-GCS matrix. The BC-GCS-Ag nanocomposite was applied as dip catalyst for the reduction of 4-nitrophenol (4NP) to 4-aminophenol (4AP), chosen as a model reaction. The results showed that the catalytic reaction was completed within 4 min, with high reusability (10 times) and without loss of catalyst. The reaction followed pseudo-first-order kinetics with a high rate constant of 0.582 min -1 . Therefore, the BC-GCS-Ag dip catalyst is an attractive alternative for environmentally friendly and sustainable catalysis, owing to its exceptional catalytic performance, high recyclability, and stability, as well as the minimal environmental footprint of the supporting materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This work reports a high-yielding, organic solvent-free, gram-scale synthesis of novel Knoevenagel condensation products by reacting carbohydrate-derived 5-substituted-2-furaldehydes (SFLs) with active methylene compounds (AMCs) using various organic amines and inorganic bases as catalysts. Among the base catalysts examined, piperidine performed best, affording satisfactory selectivity and yield of the targeted Knoevenagel condensation products owing to the subtle balance between its nucleophilicity and basicity. The reaction was optimized on various reaction parameters, such as temperature, duration, solvent, catalyst loading, and molar ratio of the reactants. Even though the SFLs exhibited significantly different reactivity, a general synthetic protocol was developed successfully, affording good to excellent isolated yields (70-96%) of the novel Knoevenagel condensation products at ambient temperature. Moreover, the Knoevenagel products were purified by triturating with eco-friendly solvents (e.g., ethyl acetate and n -heptane) without chromatographic purification., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Membrane technology is crucial in addressing water pollution challenges, particularly in removing dyes from wastewater. This study presents a novel approach to fabricating shear-aligned graphene oxide (GO) nanosheets incorporated polyvinylidene fluoride (PVDF) membranes for achieving exceptional dye rejection efficiency while maintaining high water flux. The membranes were prepared by dispersing graphene oxide within a PVDF matrix and subsequent subjection to shear alignment techniques. Shear and flow-induced alignment were explored to achieve precise and controlled alignment of graphene oxide flakes within the PVDF matrix. The resulting membranes exhibited enhanced structural integrity and optimized molecular packing of PVDF and GO, enabling them to selectively reject dyes while allowing efficient water permeation. The fabricated membranes were extensively characterized using appropriate testing methods. The results demonstrated that the shear-aligned GO sheets infused PVDF composite membranes exhibited outstanding dye rejection (96-99%) performance, surpassing conventional membranes while maintaining high water flux. This innovative membrane fabrication approach holds significant promise for advanced water treatment applications, offering a sustainable solution for selective dye removal and efficient water purification., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Awareness of electronic waste (e-waste) improves safety practices among workers, thereby reducing health risks associated with pollutants. Investigating the awareness and safe practices among these workers could help identify areas for improvement, a task not yet undertaken in Bangladesh. Consequently, this study aimed to examine the awareness, safety measures, and associated factors among e-waste workers in the country. In this cross-sectional study, 236 workers from an e-waste recycling facility located near Dhaka were interviewed using a semi-structured questionnaire from August to September 2022. Eight questions captured information on socio-demographics and work factors, 24 questions on e-waste awareness, and 11 questions on safety practices. Total awareness and safety scores were calculated and categorized as "good" and "poor" based on a cut-off point of 80% of the total score. Bivariate and regression analyses were done to determine associated factors. Only 25% of workers had good e-waste awareness; major knowledge gaps were regarding minimization, health hazards, and environmental impact. Good awareness was significantly associated with female gender, higher education, income, smoking, experience ⩾5 years, and training. About 58% followed good safety practices, but the use of boots and helmets was inadequate. Good safety practices were significantly associated with higher education, income, smoking, experience, training, and overtime work. On multivariable analysis, those with higher education had 12 times (95% CI 4.83-32.81) and 6 times (95% CI 2.94-12.81) higher odds of good awareness and practices, respectively. Trained workers had 3.6 times (95% CI 1.67-7.52) higher odds of good practices. There was a significant correlation between awareness and practices (r = .70, P < .001). The study found poor awareness and inadequate safety practices related to e-waste among the workers. Urgent interventions like training, the use of protective gear, and stringent policies are warranted to increase awareness and safety behaviors., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

This study aims to enhance the post-training evaluation of the annual performance agreement (APA) training organized by the Bangladesh Public Administration Training Centre (BPATC), the apex training institute for civil servants. Utilizing fuzzy-set qualitative comparative analysis (fsQCA) and artificial neural network (ANN) techniques within Kirkpatrick's four-stage model framework, data were collected from a self-administered questionnaire survey of 71 in-service civil servants who participated in the APA training program. This study employs an asymmetric, non-linear model analyzed through a configurational approach and ANN to explore interrelationships among the four Kirkpatrick levels namely, reaction, learning, behavior, and results. Findings indicate that trainees were satisfied across all levels, identifying a non-linear relationship among these levels in post-training evaluation process. The research highlights that "learning skills" are most significant in the APA post-training evaluation, followed by behavior, results, and reaction. Theoretically, this research advances Kirkpatrick's model and adds to the literature on public service post-training evaluation. Practically, it recommends prioritizing strategies that address cognitive barriers to enhance training effectiveness. This study's innovative approach lies in its concurrent use of fsQCA and ANN methods to analyze the success or failure of APA-related trainees, offering alternative pathways to desired outcomes and contrasting traditional quantitative methods that provide a single solution. The findings have practical implications for public service training institutions and bureaucratic policymakers involved in capacity development, guiding the creation of more effective in-service training courses for public officials. The methodology and analysis can be applied in other contexts, allowing bureaucratic policymakers to replicate these findings in their learning institutes to identify unique configurations that lead to successful or unsuccessful training outcomes, adopt effective strategies, and avoid detrimental ones., Competing Interests: The authors have declared that no competing interest exist., (Copyright: © 2024 Islam et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

A perfect protective fabric for handicapped individuals must be lightweight, waterproof, breathable, and able to absorb water. We present a multifunctional protective fabric in which one side is hydrophobic based on the intrinsic hydrophobic biopolymer polylactic acid (PLA) to keep the disabled person from getting wet, while the other side is super-hydrophilic due to embedded silica nanoparticles (NPs) to keep the disabled person safe from a sudden spill of water or other beverage on their skin or clothes. The porosity of the electrospun nanofibrous structure allows the fabric to be breathable, and the silica NPs play an important role as a perfect infrared reflector to keep the person's clothing cool on warm days. Adding white NPs, such as silicon dioxide, onto or into the textile fibers is an effective method for producing thermally insulated materials. Due to their ability to efficiently block UV light, NPs in a network keep the body cool. Such a multifunctional fabric might be ideal for adult bibs and aprons, outdoor clothing, and other amenities for individuals with disabilities.

Fog is a resource with great potential to capture fresh water from the atmosphere, regardless of the geographical and hydrological conditions. Micro-sized fog collection requires materials with hydrophilic/phobic patterns. In this study, we prepared hydrophilic poly(lactic acid) (PLA)/poly(ethylene glycol)-poly(propyl glycol)-poly(ethylene glycol) (PEG-PPG-PEG) blended nanofiber membranes with various PEG-PPG-PEG concentrations by electrospinning. Changes in the morphological and chemical properties, surface wettability, and thermal stability of the PLA/PEG-PPG-PEG composite nanofiber membranes were confirmed using field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, contact angle testing, and thermogravimetric analysis. As the PEG-PPG-PEG content of the nanofiber membranes increased, their hydrophilicity increased. Water stability, membrane porosity, and water transport rate tests were also conducted to observe the behavior of the hydrophilic PLA nanocomposite membranes in aqueous media. Finally, we applied the PLA-based membranes as fog collectors. As the PEG-PPG-PEG content of the nanofiber membranes increased, their ability to collect fog increased by over 40% compared with that collected by a pure PLA membrane. The prepared membranes not only improve the ability of fog collectors to harvest water but also broaden the use of PLA-based membranes in multiple applications, including tissue engineering, drug delivery, scaffolds, and pharmaceuticals.

Novel poly(vinyl alcohol) (PVA)/poly(vinyl butyral-vinyl alcohol) (P(VB-VA)) films with improved hydrophobicity were prepared from poly(vinyl acetate) (PVAc)/poly(vinyl butyral) (PVB) blend films with various mass ratios by saponification in a heterogeneous medium. The successful conversion of PVAc to PVA and PVAc/PVB to PVA/P(VB-VA) films was confirmed by Fourier transform infrared spectrometry, X-ray diffraction, and proton nuclear magnetic resonance analysis. This study also shows that the degree of saponification (DS) depends on the saponification time. The maximum DS of 99.99% was obtained at 96 h of saponification for all films, and the presence of PVB did not affect the DS at saponification times of 48-96 h. The effects of the PVAc/PVB blend ratio before and after saponification were determined by contact angle measurement, and the hydrophobicity was found to increase in both cases with increasing PVB content. Additionally, all the films exhibited improved mechanical properties after saponification, and the treated films possessed an unusual porous and uneven surface, in contrast with the untreated films. The prepared films with improved hydrophobicity can be used for various applications, such as biomaterials, filters, and medical devices.

Background: Phosphate (Pi) deficiency severely affects crop growth and productivity, including wheat, therefore it is necessary to develop cultivars with enhanced Pi-deficiency tolerance. However, the underlying mechanism of Pi-deficiency tolerance in wheat is still elusive. Two contrasting wheat cultivars, low-Pi tolerant Kenong199 (KN199) and low-Pi sensitive Chinese Spring (CS) were used to reveal adaptations in response to Pi deficiency at the morphological, physiological, metabolic, and molecular levels., Results: KN199 was more tolerant to Pi deficiency than CS with significantly increased root biomass and R/S ratio. Root traits, the total root length, total root surface area, and total root volume, were remarkably enhanced by Pi deficiency in KN199. The shoot total P and soluble Pi concentrations of KN199 were significantly higher than those of CS, but not in roots. In KN199, high Pi level in shoots is a higher priority than that in roots under Pi deficiency. It was probably due to differentially regulation in the miR399-mediated signaling network between the shoots of the two cultivars. The Pi deficiency-induced root architecture adaptation in KN199 was attributed to the regulation of the hormone-mediated signaling (ethylene, gibberellin, and jasmonates). The expression of genes associated with root development and Pi uptake was enhanced in KN199. Some primary metabolites (amino acids and organic acids) were significantly accumulated in roots of KN199 under Pi deficiency., Conclusions: The low-Pi tolerant wheat cultivar KN199 possessed greater morphological and primary metabolic adaptations in roots than CS under Pi deficiency. The adaption and the underlying molecular mechanisms in wheat provide a better understanding of the Pi-deficiency tolerance and the strategies for improving Pi efficiency in wheat., (© 2021. The Author(s).)

Quantum dots (QDs) are semiconducting inorganic nanoparticles, tiny molecules of 2-10 nm sizes to strength the quantum confinements of electrons. The QDs are good enough to emit light onto electrons for exciting and returning to the ground state. Here, CdSe/ZnS core/shell QDs have been prepared and applied for electrochemical sensor development in this approach. Flat glassy carbon electrode (GCE) was coated with CdSe/ZnS QDs as very thin uniform layer to result of the selective and efficient sensor of 3-CP (3-chlorophenol). The significant analytical parameters were calculated from the calibration plot such as sensitivity (3.6392 µA µM -1 cm -2 ) and detection limit (26.09 ± 1.30 pM) with CdSe/ZnS/GCE sensor probe by electrochemical approach. The calibration curve was fitted with the regression co-efficient r 2  = 0.9906 in the range of 0.1 nM ∼ 0.1 mM concentration, which denoted as linear dynamic range (LDR). Besides these, it was performed the reproducibility in short response time and successfully validated the fabricated sensor for 3-CP in the real environmental and extracted samples. It is introduced as a noble route to detect the environmental phenolic contaminants using CdSe/ZnS QDs modified sensor by electrochemical method for the safety of healthcare and environmental fields at broad scales.

In the title compound, C(26)H(14)N(4)S(2)·2CH(2)Cl(2), the two pendant benzothia-zole groups are slightly twisted with respect to the phenanthroline core [dihedral angles = 1.03 (7) and 9.05 (5)°]. Weak inter-molecular C-H⋯N and C-H⋯Cl inter-actions occur in the crystal structure.

Musk xylene(MX) is frequently used as fragrances in formulation of personal care products. Quantification of a bound 4-amino-MX(4-AMX) as cysteine adducts in trout hemoglobin(Hb) was made by gas chromatography-ion trap-mass spectrometry(GC/MS). The Hb samples were collected from trout after 24 h exposure to MX at 10 microg/g, and or menhaden oil(control). The formation of cysteine-Hb adduct was observed from nitroso derivative of MX, released by alkaline hydrolysis. The released 4-AMX metabolite was extracted in n-hexane. The extract was then reduced by evaporation, and analyzed by GC/MS. When similar agreement of mass spectral features and retention time of 4-AMX were obtained in both standard and sample solutions, the presence of 4-AMX metabolite in the Hb was confirmed. The concentration of 4-AMX was found to be 3.1 x 10(-6)--6.9 x 10(-6) mg/g in the Hb solution. Quantitation was made based on an internal standard, a calibration plot, and response factor. In the non-hydrolyzed and laboratory blank extracts, the 4-AMX metabolite was not detected. Additionally, coeluting and interfering ions were observed in the biological samples.