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Paper manufacturers have long used silicone as the coating agent for release liners. However, silicone‐based release paper is very difficult to recycle due to covalent bonds between silicone and fibers. The most suitable solution to overcome this problem is to use alternative coating materials with adequate release properties, provided that they can be easily repulped in typical paper recycling facilities. We proposed a coating agent composed of phosphate esters and dimethylacetamide in order to manufacture a recyclable and efficient release paper. Analyses carried out on coated sheets showed that phosphate esters allowed the formation of a surface with adequate release properties (low peeling force and surface free energy). In addition, the residual adhesion values obtained with phosphate esters confirmed that they are well anchored on the backing paper surface, thus limiting the mass transfer to the adhesive tape. [ABSTRACT FROM AUTHOR] more...

Phosphate concentration in natural water has been used as a water quality indicator, as it is one of the major nutrients for aquatic plants. However, the traditional phosphomolybdenum blue (PMB) method has limited sensitivity for visual or camera-based detection, leading to underestimation of the phosphate concentration. We present an ultralow-cost, rapid field preconcentration and digital image colorimetric sensing of low-concentration phosphate method for water analysis. A novel hand-powered paper centrifuge (paperfuge) is used for sample preparation and preconcentration. This paperfuge is made of two circular paper discs and a string. Six centrifuge tubes (CTs) originally used as glue dispensing tips with a sample capacity of ∼230 μL, are loaded on the paperfuge. After sampling, phosphate in the water sample is reacted to form PMB. Then, the reacted sample is drawn into a CT using an autopipette before the CT bottom is sealed by glue. After Oasis® HLB sorbents are added through the top of the CT, the CT top is also sealed with glue. The HLB sorbents adsorb PMB and are accumulated in the CT tip through centrifugation. The CT tips are cut and analyzed with the ImageJ software. It was found that the blue color intensity of sorbents is in a linear relationship to the phosphate concentration, with a linear range of 0–5 μM (r2 = 0.9921) and limit of detection of 0.19 μM. In addition, this method has been applied to in-field water analysis. The results are in agreement with the standard PMB method. [ABSTRACT FROM AUTHOR] more...

Contamination of waterways is of increasing concern, with recent studies demonstrating elevated levels of antibiotics, antidepressants, household, agricultural and industrial chemicals in freshwater systems. Thus, there is a growing demand for methods to rapidly and conveniently monitor contaminants in waterways. Here we demonstrate how a combination of paper microfluidic devices and handheld mobile technology can be used by citizen scientists to carry out a sustained water monitoring campaign. We have developed a paper-based analytical device and a 3 minute sampling workflow that requires no more than a container, a test device and a smartphone app. The contaminant measured in these pilots are phosphates, detectable down to 3 mg L-1. Together these allow volunteers to successfully carry out cost-effective, high frequency, phosphate monitoring over an extended geographies and periods. [ABSTRACT FROM AUTHOR] more...

Aim. To evaluate in vitro the antibacterial effect of a paper made of silver phosphate cellulose fibers (SPCF) on Staphylococcus aureus, the most common diabetic foot ulceration (DFU) pathogen when compared with other common commercial products. Methods. The antibacterial activity of SPCF samples was evaluated through time with cell counting on agar plates. SPCF samples were then compared with commercial wound care products currently in use in DFU treatments (Silvercel™, Acticoat 7, and Aquacel Ag ExtraTM) through time on agar plates (growth inhibition zones). Results. After 6 hours, there was no viable bacterial cell detected on either plate (p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 (p < 0.05) and superior to Aquacel AG ExtraTM and Silvercel™ at lower silver concentrations (p < 0.001). Conclusions. These results have shown the efficiency of SPCF paper to eliminate Staphylococcus aureus in these conditions. SPCF papers are effective when compared with other common commercial products and could have an industrial potential in wound care. Infected DFU could benefit from the antibacterial effectiveness of SPCF, but more relevant experimentations related to foot ulcers are needed. [ABSTRACT FROM AUTHOR] more...

Herein we describe a novel reagentless paper-based electrochemical phosphate sensor, manufactured with a simple and inexpensive approach. By following three easy steps, consisting of wax patterning, paper chemical modification, and electrode screen-printing, the filter paper provides an effective electroanalytical platform to sense phosphate ions in standard solutions and real samples (river water). The electrochemical properties of the paper-based platform were evaluated, firstly, by using ferricyanide as a redox mediator, proving no analyte-entrapment due to the cellulose lattice. Then, the reference colorimetric method for phosphate ions, which is based on the formation of phosphomolybdic complex, was successfully adapted to a reagentless electrochemically paper-based platform. This novel and highly sustainable configuration readily allows for the determination of phosphate ions with high reproducibility and long storage stability, achieving a detection limit of 4 μM over a wide linear range up to 300 μM. This in-house approach would be able to generically develop an affordable in situ and user-friendly sensing device without the addition of any reagent, to be applied for a broad range of analytes. [ABSTRACT FROM AUTHOR] more...

This manuscript describes the development and clinical testing of a paper-based, metabolic assay designed for rapid, semi-quantitative measurement of organophosphate poisoning. Paper-based platforms, including point-of-care devices and 96-well plates, provided semi-quantitative information regarding the concentration of AchE (a biomarker for organophosphate poisoning). The paper-based 96-well-plate developed and implemented in this study was used to measure the level of organophosphate poisoning in three different clinical patients. Results were comparable to those obtained using conventional hospital methods currently considered the “gold standard”. This diagnostic device offers several advantages over conventional methods, including short operating time (twice as fast as conventional methods), procedure simplicity, and reduced fabrication cost. With further commercialization efforts, the methods described in this manuscript could be applied to a wide range of potential diagnostic applications in the field. [ABSTRACT FROM AUTHOR] more...

In this work, we report atomic-scale reconstruction processes in Fe-Ce oxide-based composites (hydrothermally precipitated at Fe-to-Ce dosage ratios of 1:0, 2:1, 1:1, 1:2, and 0:1), upon treatment at 300 °C. The structural changes are correlated with the adsorptive removal of arsenate, phosphate, fluoride, bromide, and bromate. The presence of the carbonate-based Ce-component and surface sulfate in precursor samples creates favorable conditions for phase transformation, resulting in the formation of novel (unknown) layered compounds of Fe and Ce. These compounds are of the layered double hydroxide type, with sulfate in the interlayer space. In spite of general awareness of the importance of surface area in adsorptive removal, the increase in surface area upon thermal treatment did not increase adsorption of the studied anions. However, EXAFS simulations and the adsorption tests provided evidence of regularities between local structures of Fe in composites obtained at 80 and 300 °C and adsorption performance of most studied anions. The best adsorption of tetrahedral anions was demonstrated by samples whose simulated outer Fe shells resulted from oscillations from both O and Fe atoms. In contrast, the loss of extended x-ray absorption fine structure was correlated with the decrease of adsorptive removal. Both Fe K-edge and Ce L 3 -edge EXAFS suggested the formation of solid solutions. For the first time, the utilization of extended x-ray absorption fine structure is suggested as a methodological approach (first expressed in the companion paper) to estimate the surface reactivity of inorganic materials intended for use as anion exchange adsorbents. [ABSTRACT FROM AUTHOR] more...

Aim: The purpose of this work was to study the feasibility of producing economic flame retardant bacterial cellulose (BC) and evaluating its behaviour in paper production. Methods and Results: This type of BC was prepared by Gluconacetobacter subsp . xylinus and substituting the glucose in the cultivation medium by glucose phosphate as a carbon source; as well as using corn steep liquor as a nitrogen source. The investigated processing technique did not dispose any toxic chemicals that pollute the surroundings or cause unacceptable effluents, making the process environmentally safe. The fire retardant behaviour of the investigated BC has been studied by non-isothermal thermogravimetric analysis (TGA & DTGA). The activation energy of each degradation stage and the order of degradation were estimated using the Coats–Redfern equation and the least square method. Strength, optical properties, and thermogravimetric analysis of BC-phosphate added paper sheets were also tested. Conclusions: The study confirmed that the use of glucose phosphate along with glucose was significant in the high yield production of phosphate containing bacterial cellulose (PCBC1); more so than the use of glucose phosphate alone (PCBC2). Incorporating 5% of the PCBC with wood pulp during paper sheet formation was found to significantly improve kaolin retention, strength, and fire resistance properties as compared to paper sheets produced from incorporating bacterial cellulose (BC). Significance and Impact of the Study: This modified BC is a valuable product for the preparation of specialized paper, in addition to its function as a fillers aid. [ABSTRACT FROM AUTHOR] more...

Lithium iron phosphate (LFP) batteries are widely utilized in energy storage systems due to their numerous advantages. However, their further development is impeded by the issue of thermal runaway. This paper offers a comparative analysis of gas generation in thermal runaway incidents resulting from two abuse scenarios: thermal abuse and electrical abuse. The study initially focuses on 13-Ah lithium iron phosphate single-cell batteries. Experiments were conducted to induce thermal runaway through both forms of abuse, analyzing the production and dispersion of H2 and CO gases in each case. It was observed that thermal abuse–induced thermal runaway resulted in higher gas concentrations and more pronounced fluctuations, whereas electrical abuse–induced thermal runaway exhibited lower gas concentrations and lower fluctuations. Subsequently, key materials and temperature variations at the positive and negative electrodes were investigated under both types of thermal runaway, revealing distinct differences that are identified as the primary reasons for the significant disparities in H2 and CO gas generation during the two thermal runaway conditions. The conclusions drawn in this paper advance the understanding of the mechanisms underlying H2 and CO gas concentration generation in thermal runaway scenarios. [ABSTRACT FROM AUTHOR] more...

Ultralong nanowires with ultrahigh aspect ratios exhibit high flexibility, and they are promising for applications in various fields. Herein, a cadmium oleate precursor hydrothermal method is developed for the synthesis of ultralong nanowires of cadmium phosphate hydroxide. In this method, water-soluble cadmium salt is used as the cadmium source, water-soluble phosphate is used as the phosphorus source, and sodium oleate is adopted as a reactant to form cadmium oleate precursor and as a structure-directing agent. By using this method, ultralong nanowires of cadmium phosphate hydroxide are successfully synthesized using CdCl2, sodium oleate, and NaH2PO4 as reactants in an aqueous solution by hydrothermal treatment at 180 °C for 24 h. In addition, a new type of flexible fire-resistant inorganic paper with good electrical insulation performance is fabricated using ultralong nanowires of cadmium phosphate hydroxide. As an example of the extended application of this synthetic method, ultralong nanowires of cadmium phosphate hydroxide can be converted to ultralong CdS nanowires through a convenient sulfidation reaction. In this way, ultralong CdS nanowires are successfully synthesized by simple sulfidation of ultralong nanowires of cadmium phosphate hydroxide under mild conditions. The as-prepared ultralong nanowires of cadmium phosphate hydroxide are promising for applications as the precursors and templates for synthesizing other inorganic ultralong nanowires and have wide applications in various fields. [ABSTRACT FROM AUTHOR] more...

The diverse etiologies of the genetic neurodegenerative disorder known as primary familial brain calcification have dimmed hopes for curative therapies. However, two new papers in Neuron 1,2 provide a reason for optimism by identifying mechanisms involved in brain phosphate transport and a promising target for restoring phosphate balance in the brain. The diverse etiologies of the genetic neurodegenerative disorder known as primary familial brain calcification have dimmed hopes for curative therapies. However, two new papers in Neuron provide a reason for optimism by identifying mechanisms involved in brain phosphate transport and a promising target for restoring phosphate balance in the brain. [ABSTRACT FROM AUTHOR] more...

Paper sludge, which is an industrial waste generated during the manufacture of recycled paper products, was converted into an effective phosphate (PO4 3−) sequestration agent through calcination and its removal behavior toward phosphate ion in aqueous solution was examined. Paper sludge contains mainly cellulose fibers and inorganic fillers together with coating materials such as calcite and kaolinite. The sludge was calcined at temperatures between 200 and 1000°C for 6h. Crystalline phases originally present were altered at increasing temperatures (up to 800°C) in the order kaolinite more...

Abstract: The diffusive gradients in thin films (DGT) technique has shown enormous potential for labile metal monitoring in fresh water due to the preconcentration, time-integrated, matrix interference removal and speciation analytical features. In this work, the coupling of energy dispersive X-ray fluorescence (EDXRF) with paper-based DGT devices was evaluated for the direct determination of Mn, Co, Ni, Cu, Zn and Pb in fresh water. The DGT samplers were assembled with cellulose (Whatman 3 MM chromatography paper) as the diffusion layer and a cellulose phosphate ion exchange membrane (Whatman P 81 paper) as the binding agent. The diffusion coefficients of the analytes on 3 MM chromatography paper were calculated by deploying the DGT samplers in synthetic solutions containing 500μgL-1 of Mn, Co, Ni, Cu, Zn and Pb (4L at pH 5.5 and ionic strength at 0.05molL-1). After retrieval, the DGT units were disassembled and the P 81 papers were dried and analysed by EDXRF directly. The 3 MM chromatographic paper diffusion coefficients of the analytes ranged from 1.67 to 1.87×10-6 cm2 s-1. The metal retention and phosphate group homogeneities on the P 81 membrane was studied by a spot analysis with a diameter of 1mm. The proposed approach (DGT-EDXRF coupling) was applied to determine the analytes at five sampling sites (48h in situ deployment) on the Piracicaba river basin, and the results (labile fraction) were compared with 0.45μm dissolved fractions determined by synchrotron radiation-excited total reflection X-ray fluorescence (SR-TXRF). The limits of detection of DGT-EDXRF coupling for the analytes (from 7.5 to 26μgL-1) were similar to those obtained by the sensitive SR-TXRF technique (3.8 to 9.1μgL-1). [Copyright &y& Elsevier] more...

Abstract: A reversed-phase high performance liquid chromatographic method was developed and validated for the quantitative determination of amodiaquine (AQ) and its metabolite desethylamodiaquine (DAQ) in whole blood collected on filter paper. The structure analogue 4-(4-dimethylamino-1-methylbutylamino)-7-chloroquinoline was used as internal standard. Upon collection, blood was added to 10% phosphoric acid in a 1:1 ratio and then spotted onto filter paper. The samples were alkalinized (pH≈9.2) with potassium hydroxide at the time of assay and the compounds were extracted together with internal standard into di-isopropyl ether and then re-extracted into an aqueous phase with 0.1M phosphate buffer at pH 4. The chromatographic analysis was performed using an Agilent Technologies ChemStation LC System. The absorbance of the compounds was monitored at 333nm. Mean extraction recoveries of AQ and DAQ were 49 and 48%, respectively. Intra-day and inter-day coefficients of variation were <10.5%. The limit of quantification was 50nM for both compounds (sample size 100μl). Both AQ and DAQ that were previously reported to be unstable have been stored on filter paper for at least 19 weeks. The method was applied on samples from healthy volunteers. [Copyright &y& Elsevier] more...

Among surface mining methods, strip mining is a widely used technique for extracting mineral resources. This method is suitable for most near-surface stratiform sedimentary deposits and has historically been linked to surface mining of deposits such as coal, phosphates, and other natural substances. Given the significant economic interest that strip mining represents, it is in the best interest of mining companies to exploit as much of the reserves as possible using this technique, as it offers many advantages compared to open-pit or underground methods, particularly regarding safety and ore recovery rates. Today, the exploited deposits have become deeper, making the strip mining process more complex. Hence, there is a need for certain adaptations and the introduction of new techniques to address these geological conditions that threaten the feasibility of this method. This article explores the challenges that strip mining faces in contexts of thick overburden and subsequently presents the various techniques proposed by researchers worldwide aimed at overcoming these difficulties. The paper is based on an in-depth review of existing literature that deals with case studies of open-cast mines in different contexts. The examination of various approaches and techniques used for optimizing exploitation under thick overburden conditions by strip mining, along with their limitations, is presented. [ABSTRACT FROM AUTHOR] more...

Transition metal phosphates with hollow structure have attracted substantial attentions as high-performance electrocatalyst for oxygen evolution reaction (OER). However, these electrocatalytic materials need conductive carrier to realize efficient charge transfer and further improve the OER activity. In this work, ZIF-67 derived hollow NiCo phosphate nanocages supported by waste paper-based carbon aerogel (NCP@WPCA) was prepared as high-efficiency and stable electrocatalyst. Benefited from the enhanced electrochemical active surface area and fast gas emission, the NCP@WPCA catalyst exhibits superior OER activity with low overpotential of 351 mV at current density of 10 mA cm−2, along with good stability in alkaline solution. Additionally, the waste paper-based carbon aerogel as the carrier for electrocatalysts achieves low-cost waste reuse. [Display omitted] [ABSTRACT FROM AUTHOR] more...

Simple Summary: In spontaneous tumor regression, tumors shrink and disappear without conventional treatments. This phenomenon challenges the view that cancer is an irreversible genetic disease and that the only treatment option is to kill cancer cells or surgically remove them. In tumor reversion, cancer cells have been shown to return to normal cells when they are transplanted into a normal cellular environment. Additionally, people consuming a Western diet ingest excessive amounts of dietary phosphate, and a dysregulated oversupply of phosphate can be transported into cells, stimulating the cellular growth that forms tumors. Based on reviewed evidence, this paper proposes that reducing excessive dietary phosphate potentially activates tumor regression and reversion, as components of cancer cells are self-digested. Furthermore, fevers and fasting-mimicking diets are associated with tumor regression, which also may be initiated by reduced phosphate intake. Studies are needed to test dietary phosphate reduction in tumor regression and reversion to improve cancer patient survival. Tumors that spontaneously shrink from unknown causes in tumor regression, and that return to normal cells in tumor reversion, are phenomena with the potential to contribute new knowledge and novel therapies for cancer patient survival. Tumorigenesis is associated with dysregulated phosphate metabolism and an increased transport of phosphate into tumor cells, potentially mediated by phosphate overload from excessive dietary phosphate intake, a significant problem in Western societies. This paper proposes that reduced dietary phosphate overload and reregulated phosphate metabolism may reverse an imbalance of kinases and phosphatases in cell signaling and cellular proliferation, thereby activating autophagy in tumor regression and reversion. Dietary phosphate can also be reduced by sickness-associated anorexia, fasting-mimicking diets, and other diets low in phosphate, all of which have been associated with tumor regression. Tumor reversion has also been demonstrated by transplanting cancer cells into a healthy microenvironment, plausibly associated with normal cellular phosphate concentrations. Evidence also suggests that the sequestration and containment of excessive phosphate within encapsulated tumors is protective in cancer patients, preventing the release of potentially lethal amounts of phosphate into the general circulation. Reducing dietary phosphate overload has the potential to provide a novel, safe, and effective reversion therapy for cancer patients, and further research is warranted. [ABSTRACT FROM AUTHOR] more...

Abstract: The preparation and evaluation of a simple paper-based device for the determination of reactive phosphate in natural and soil waters based on the formation of phosphomolybdenum blue is reported. Hydrophilic reagent zones were defined by printing filter paper with a hydrophobic paper-sizing agent using an inkjet printer. The molybdate/potassium antimony(III)-tartrate reagent and ascorbic acid reductant merged together from adjacent hydrophilic zones after spotting the liquid sample onto the paper. The colour intensity of the phosphoantimonylmolybdenum blue complex produced was measured using a flat bed scanner. Under optimal conditions, the paper-based device is characterised by a working range of 0.2–10mgL−1 P, limits of detection and quantitation of 0.05 and 0.16mgL−1 P, respectively, and repeatability of less than 2% RSD at 1 and 5mgL−1 P (n=10 and 8). There was no significant difference between the results obtained using the paper-based device and reference methods (t=0.0135, P (T≤t) two-tail=0.9892, df=38). In its optimum form, the paper-based device was stable for up to 15 day under ambient conditions, and up to 122day when stored at ≤−20°C. The small dimensions, minimal reagent consumption, low cost (a few cents), ease of operation and favourable analytical performance make the proposed paper-based device attractive for on-site environmental monitoring and analysis. [Copyright &y& Elsevier] more...

Abstract: Paper surfaces (Whatman filter papers, Kimwipes®, and Japanese Washi papers) were employed as support for gold nanoparticles (AuNPs) deposited by the seed-mediated growth method. The AuNP-modified paper or textile was brought into “weak” (or non-permanent) contact with a glassy carbon electrode and immersed into aqueous electrolyte media. Electrochemical responses for the Fe(CN)6 4−/Fe(CN)6 3− redox system in 0.1M phosphate buffer (pH 7.0) and 1.0M KCl solutions were investigated by voltammetry and impedance methods. Even for weakly contacted AuNP catalysts of relatively low density faster electron transfer was observed. Particle sizes of at least 20nm diameter were required. There was no permanent contact from AuNP catalysts to the electrode and the process was therefore termed “weak contact catalysis”. The method is proposed as a rapid and novel catalyst screening tool with potential applications in fuel cell and sensor technologies. [Copyright &y& Elsevier] more...

Fast, simple, and low-cost on-site visualized detection of inorganic phosphate (Pi) is in great demand since phosphate is the major reason of eutrophication. In this work, a ratiometric fluorescent probe composed by green carbon dots (GCDs) and red carbon dots (RCDs) has been established for high-sensitivity and selective sensing of Pi. A trend of color change from red to green is observed for the detection of Pi under ultraviolet light and the detection limit is 0.09 μM in the range of 0 to 55 μM. Fluorescent test paper prepared from the probe solution was successfully applied to semi-quantitative visual detection of Pi in real-world water and soil samples, which shows great real-world application potentials. [ABSTRACT FROM AUTHOR] more...

There is an increasing interest in new strategies to rapidly detect analytes of clinical and environmental interest without the need for sophisticated instrumentation. As an example, the detection of acetylcholinesterase (AChE) inhibitors such as neurotoxins and organophosphates has implications for neuroscience, drug assessment, pharmaceutical development, and environmental monitoring. Functionalization of suthices with multiple reagents, including enzymes and chromogenic reagents, is a critical component for the effective development of "dipstick" or lateral flow biosensors. Herein, we describe a novel paper-based solid-phase biosensor that utilizes piezoelectric inkjet printing of biocompatible, enzyme-doped, sol-gel-based inks to create colorimetric sensor strips. For this purpose, polyvinylamine (PVAm, which captures anionic agents) was first printed and then AChE was overprinted by sandwiching the enzyme within two layers of biocompatible sol-gel-derived silica on paper. AChE inhibitors, including paraoxon and aflatoxin B1, were detected successfully using this sensor by measuring the residual activity of AChE on paper, using Ellman's colorimetric assay, with capture of the 5-thio-2-nitrobenzoate (FNB) product on the PVAm layer. The assay provided good detection limits (paraoxon, ~100 nM; aflatoxin B1,~30 nM) and rapid response times (<5 min). Detection could be achieved either by eye or using a digital camera and image analysis software, avoiding the need for expensive and sophisticated instrumentation. We demonstrate that the bioactive paper strip can be used either as a dipstick or a lateral flow-based biosensor. The use of sol-gel-based entrapment produced a sensor that retained enzyme activity and gave reproducible results after storage at 4°C for at least 60 days, making the system suitable for storage and use in the field. [ABSTRACT FROM AUTHOR] more...

Abstract: The effects of the addition of ammonium magnesium phosphate (AMP) to the paper of an electrically heated cigarette (EHC) prototype on smoke composition and toxicity were quantified and the underlying mechanisms investigated. Smoke from EHC prototypes with and without AMP and from conventional cigarettes, i.e. the University of Kentucky Standard Reference Cigarette 1R4F and eight American-blend market cigarettes, was compared. Endpoints for comparison were smoke chemistry, where toxic constituents were measured, cytotoxic activity, as measured in murine fibroblasts embryo cells by the Neutral Red Uptake Assay, and genotoxic activity, as measured in bacteria by the Salmonella Reverse Mutation Assay and in murine lymphoma cells by the TK Assay. The addition of AMP to the EHC led to a reduction of toxic substances and toxicological activity of approximately 30% compared to the EHC without AMP. Compared to the conventional cigarettes, the EHC with AMP showed reductions of 75–90%. Smoke from the EHCs generated in nitrogen atmospheres supplemented with different concentrations of ammonia and oxygen was assayed for its in vitro cytotoxicity and genotoxicity. The results indicate that the ammonia released by AMP at the heating site of the EHC is responsible for the reductions in cytotoxicity and mutagenicity for the EHC with AMP compared with the EHC without AMP. Thus, while the EHC approach distinctly reduces toxic smoke constituents compared to conventional cigarettes, the use of AMP in the paper of an EHC leads to further distinct reductions. In the study presented here, in vitro assays were used as quantitative tools to investigate toxicity-related mechanisms. [Copyright &y& Elsevier] more...

Al-containing CaO–SiO2–H2O phases were prepared by hydrothermal treatment of mixtures of paper sludge ash (PSA) with various silica and calcia sources and their properties were determined with particular reference to the simultaneous uptake of ammonium and phosphate ions, which are implicated in the eutrophication of lakes and ponds. After examination of various silica and calcia sources, Ca(OH)2 and SiO2 sol were selected as the most appropriate starting materials. Dry milling was found to be superior to wet milling in avoiding contamination from the milling media during mixing. Nine samples with three different Ca/Si ratios and Al2O3 contents were prepared with various mass ratios of Ca(OH)2, PSA and SiO2. The chemical compositions of the hydrothermal products of these mixtures moved towards the tieline of CaSiO3-PSA, with respect to the starting compositions. The major phase formed in all samples was poorly crystalline C–S–H(I), with hydroxysodalite also formed in the Al-containing mixtures. All the products showed a capacity for the simultaneous uptake of ammonium and phosphate ions. The saturated sorption capacities calculated from the Langmuir equation ranged from 0. 9 to 2. 4mmol/g for the ammonium ion and from 3. 3 to 5. 2mmol/g for the phosphate ion. Since the sorption capacities for both ions increased with increasing Ca contents of the product, substitution of Ca2+ for NH4 + and the formation of calcium phosphate phases such as apatite and brushite by precipitation are thought to be the main sorption mechanisms. [Copyright &y& Elsevier] more...

Phosphate is an essential nutrient for heterotrophic bacteria, affecting bacterioplankton in aquatic ecosystems and bacteria in biofilms. However, the influence of phosphate limitation on bacterial competition and biofilm development in multispecies populations has received limited attention in existing studies. To address this issue, we isolated 13 adhesive bacteria from paper machine aggregates. Intergeneric inhibition of Pseudomonas aeruginosa WW5 by Serratia marcescens WW4 was identified under phosphate-limited conditions, but not in Luria- Bertani medium or M9 minimal medium. The viable numbers of the pure S. marcescens WW4 culture decreased over 3 days in the phosphate-limited medium; however, the mortality of S. marcescens WW4 was significantly reduced when it was co-cultured with P. aeruginosa WW5, which appeared to sustain the S. marcescens WW4 biofilm. In contrast, viable P. aeruginosa WW5 cells immediately declined in the phosphate-limited co-culture. To identify the genetic/inhibitory element(s) involved in this process, we inserted a mini- Tn5 mutant of S. marcescens WW4 that lacked inhibitory effect. The results showed that an endonuclease bacteriocin was involved in this intergeneric inhibition by S. marcescens WW4 under phosphate limitation. In conclusion, this study highlights the importance of nutrient limitation in bacterial interactions and provides a strong candidate gene for future functional characterisation. [ABSTRACT FROM AUTHOR] more...

The key criteria for assessing the success of bone tissue engineering are the quality and quantity of the produced minerals within the cultured constructs. The accumulation of calcium ions and inorganic phosphates in culture medium serves as nucleating agents for the formation of hydroxyapatite, which is the main inorganic component of bone. Bone nodule formation is one of the hallmarks of mineralization in such cell cultures. In this study, we developed a new two-step procedure to accelerate bone formation in which mouse bone cell aggregates were produced first on various chemically treated non-adhesive substrates. After this step, the bone cells' growth and mineralization were followed in conventional culture plates. The number and size of cell aggregates were studied with light microscopy. The minerals' formation in the form of nodules produced by the cell aggregates and the bone crystal quality were studied with Fourier Transform Infrared (FTIR) spectroscopy. The FTIR spectra of the ash specimens (mineral phase only) from thermal gravimetric analysis (TGA) provided valuable information of the quality of the minerals. The 4PO4region (550–650 cm−1), which reveals apatitic and non-apatitic HPO4or PO4environments, and phosphate region (910–1180 cm−1) were examined for the minerals produced in the form of nodules. The peak position and intensity of the spectra demonstrate that the quality of the bone produced by cell aggregates, especially from the bigger ones, which were formed on Plunoric treated substrates, exhibit a composition more similar to that of native bone. This work establishes a new protocol for high quality bone formation and characterization, with the potential to be applied to bone tissue engineering. [ABSTRACT FROM AUTHOR] more...

The effectiveness of a Pi (iron oxide-impregnated paper) method was compared with that of Bray-1 method in extracting phosphorus (P) from an acid Hartsells silt loam (Typic Hapludult, pH 4.8) treated with low-release P fertilizers derived from Dorowa (Zimbabwe) phosphate rock (DPR) with maize (Zea mays L) as indicator crop in a randomized block design greenhouse experiment with three replicates. The fertilizers used were finely ground DPR, partially acidulated DPR (PADPR), a compacted mixture of DPR + triple superphosphate (TSP) + urea + potassium chloride (DTUK) with half of P from DPR and half from TSP, and a commercial grade single superphosphate (SSP) as a standard. The results indicated that the correlation between Bray-1 and Pi-extractable P was high (r = 97***). The regression coefficients for dry matter yield (DMY) and P uptake (PUPT) as a function of Bray-1 P level of SSP (DMY = 1.16 + 0.24Bray-1 P; PUPT = 0.93 + 0.45Bray-1 P) were significantly lower (p < 0.001) than those for DTUK (DMY = 1.16 + 0.43Bray-1 P; PUPT = 0.93 + 0.74Bray-1 P) and PADPR (DMY = 1.16 + 0.47Bray-1 P; PUPT = 0.93 + 0.82Bray-1 P). That is, a given soil-extractable P level with SSP resulted in a lower dry matter yield or P uptake than that from DTUK and PADPR. Thus, Bray-1 underestimated the agronomic effectiveness of DTUK and PADPR with respect to SSP. Based on this greenhouse research, soil testing for fertilizer recommendations using the Bray-1 test may result in two different response functions, one for water-soluble P sources and another for water-insoluble P sources. [ABSTRACT FROM AUTHOR] more...

[Display omitted] • A Turn-On fluorescent sensor for Al3+. • Relay sensing of Pi, PPi, ADP, ATP. • Low detection limit. • Filter paper strips for real time detection. We have developed an unsymmetrical Schiff-base ligand H 3 L which selectively senses Al3+ over all other metal ions in ethanol–water mixture (1:1). There is dramatic increase in the intensity of fluorescence on addition of Al3+ to the solution of ligand in EtOH/H 2 O mixture. NMR studies, HRMS results and fluorescence experiments have been conducted to confirm the binding mode of different metals with H 3 L. The detection limit for aluminum ion is 72.6 × 10−9 M. The L-Al3+ complex has been subsequently used to detect inorganic and organic phosphates. An "On-Off-On" relay recognition of Al3+ ion and different phosphate and pyrophosphate ions, ATP and ADP has been achieved. The probe has shown good reversibility behavior based on which truth table and logic gate was designed. Lifetime and quantum yield values have been measured in an effort to investigate the sensing ability of the ligand. Cost effective real-time detection of Al3+ has been demonstrated by filter paper strips. [ABSTRACT FROM AUTHOR] more...

High concentrations of certain nutrients, including phosphate, are known to lead to undesired algal growth and low dissolved oxygen levels, creating deadly conditions for organisms in marine ecosystems. The rapid and robust detection of these nutrients using a colorimetric, paper-based system that can be applied on-site is of high interest to individuals monitoring marine environments and others affected by marine ecosystem health. Several techniques for detecting phosphate have been reported previously, yet these techniques often suffer from high detection limits, reagent instability, and the need of the user to handle toxic reagents. In order to develop improved phosphate detection methods, the commonly used molybdenum blue reagents were incorporated into a paper-based, colorimetric detection system. This system benefited from improved stabilization of the molybdenum blue reagent as well as minimal user contact with toxic reagents. The colorimetric readout from the paper-based devices was analyzed and quantified using RGB analyses (via ImageJ), and resulted in the detection of phosphate at detection limits between 1.3 and 2.8 ppm in various aqueous media, including real seawater. [ABSTRACT FROM AUTHOR] more...

[Display omitted] • Detection of PO 4 3− using dye adsorption and molybdenum blue reactions. • The probe enabled naked-eye detection of PO 4 3− in the range of 0.27–13.6 mg/L. • The fabricated probe is stable, ready to use, and portable. • Detection of PO 4 3− in real water samples was satisfactory. • The developed probe is cost effective compared to other detection methods. Phosphorus is one of the vital nutrients for sustenance; however, its excess concentration can cause adverse impacts on the ecosystem. Numerous sensors have been developed and deployed to monitor phosphate ions (Pi) in the environment in the past decade. However, their high cost, non-portability, and lengthy and complex fabrication processes are detrimental to their widespread use. Accordingly, the objective of the study was to develop a low-cost, convenient paper-based colorimetric sensor with brilliant green (BG) as the probe. The use of triarylmethane dye as a colouring reagent allows naked eye-visible detection of Pi in the range of 13.6–0.27 mg L−1 with the limit of detection as 0.07 mg L−1. Moreover, the proposed sensor resolves the challenges of traditional methods like the formation of insoluble complexes, the requirement of surfactants, poor reagents storability, dependence on time and temperature. The sensitivity and selectivity of BG toward Pi was verified in the aqueous phase. Later, the paper-based sensor (W-BG) was developed via dip coating as a portable detection tool. The storability, stability, and applicability of the developed strips were tested and validated using FT-IR, UV-DRS, and XRD. Additionally, the performance of the strips was compared with a microfluid paper-based device to ensure the feasibility and versatility of the strips. The sensing mechanism is deduced as the formation of the phosphomolybdate complex, which was responsible for the delocalization of the lone pair of electrons on BG, thus rendering a distinct endpoint. The selectivity and sensitivity of the sensor were maintained in real water and wastewater samples. Overall, with affordable cost (0.08 $) and portability, W-BG can be considered as a smart and environmentally friendly water quality monitoring tool. [ABSTRACT FROM AUTHOR] more...

The growing number of high-resolution crystal structures of large RNA molecules provides much information for understanding the principles of structural organization of these complex molecules. Several in-depth analyses of nucleobase-centered RNA structural motifs and backbone conformations have been published based on this information, including a systematic classification of base pairs by Leontis and Westhof. However, hydrogen bonds involving sugar–phosphate backbone atoms of RNA have not been analyzed systematically until recently, although such hydrogen bonds appear to be common both in local and tertiary interactions. Here we review some backbone structural motifs discussed in the literature and analyze a set of eight high-resolution multi-domain RNA structures. The analyzed RNAs are highly structured: among 5372 nucleotides in this set, 89% are involved in at least one “long-range” RNA–RNA hydrogen bond, i.e., hydrogen bonds between atoms in the same residue or sequential residues are ignored. These long-range hydrogen bonds frequently use backbone atoms as hydrogen bond acceptors, i.e., OP1, OP2, O2′, O3′, O4′, or O5′, or as a donor (2′OH). A surprisingly large number of such hydrogen bonds are found, considering that neither single-stranded nor double-stranded regions will contain such hydrogen bonds unless additional interactions with other residues exist. Among 8327 long-range hydrogen bonds found in this set of structures, 2811, or about one-third, are hydrogen bonds entailing RNA backbone atoms; they involve 39% of all nucleotides in the structures. The majority of them (2111) are hydrogen bonds entailing ribose hydroxyl groups, which can be used either as a donor or an acceptor; they constitute 25% of all hydrogen bonds and involve 31% of all nucleotides. The phosphate oxygens OP1 or OP2 are used as hydrogen bond acceptors in 12% of all nucleotides, and the ribose ring oxygen O4′ and phosphodiester oxygens O3′ and O5′ are used in 4%, 4%, and 1% of all nucleotides, respectively. Distributions of geometric parameters and some examples of such hydrogen bonds are presented in this report. A novel motif involving backbone hydrogen bonds, the ribose–phosphate zipper, is also identified. [ABSTRACT FROM AUTHOR] more...

Proteins that have a histidine triad in their active sites belong to the HIT-protein superfamily. They are ubiquitous, are involved in the metabolism of different nucleotides and catalyze their hydrolysis and/or phosphorolysis liberating either the corresponding 5′-NMP or 5′-NDP, respectively. We studied substrate specificity of nine recombinant HIT-proteins with adenosine 5′-phosphosulfate (1), adenosine 5′-phosphoramidate (2), adenosine 5′-phosphorothioate (3), adenosine 5′-phosphorofluoride (4), diadenosine 5′,5′′′-P1,P3-triphosphate (5), di(7-methylguanosine) 5′,5′′′-P1,P3-triphosphate (6) and adenosine 5′-hypophosphate (7). Preferences for the recognition of these compounds as substrates by individual proteins differed. All the proteins hydrolyzed (1) but the Arabidopsis thalianaHint1 did it very slowly. None of the proteins cleaved (7). Only A. thalianaHint1 and Escherichia coliHinT hydrolyzed (3). Three proteins known as dinucleoside triphosphatases, human and A. thalianaFhit-proteins and Trypanosoma bruceiHIT-45, cleaved (1), (2), (4), (5) and (6). Caenorhabditis elegansdecapping protein DcpS degraded (1), (5), (6) and poorly (4). A. thalianaaprataxin-like protein and Hint4 hydrolyzed only (1), (2) and (4), in that order of efficiency. Velocities of those reactions and some Kmvalues were determined. Applicability of this study to the metabolism of certain nucleotidyl-derivatives is discussed. [ABSTRACT FROM AUTHOR] more...

The aim of our study was to obtain new details on the role of phosphate residues in antigenomic hepatitis delta virus (HDV) ribozyme for the development of metal ion binding sites and their participation in the cleavage mechanism. In these studies, the wild-type ribozyme and four in vitroselected variants, R37, R20, R25 and R51, were used. The application of nucleotide phosphorothioates and the NAIM (nucleotide analog interference mapping) technique for the cis-acting ribozymes, wild-type, R25 and R51, revealed the importance of the J4/2 and P1.1 regions in the catalysis. Interestingly, in the wild-type ribozyme, the largest interference effects were observed close to catalytic C76 in the presence of Ca2+, while in the case of Mg2+were in the structurally important helix P1.1. The results obtained for R25 and R51 suggest different coordination of the divalent ions to the phosphate residues within the ribozyme catalytic core. Additionally, replacing the non-bridging oxygen atoms on sulfur in a phosphate group at the cleavage site in trans-acting ribozyme variants showed that interactions between pro-RPand pro-SPoxygen atoms, and catalytic metal ions, had moderate effects on the cleavage reaction. In the wild-type ribozyme, the ratio of SP/RPisomer cleavage rates decreased from 25 for Mg2+-induced cleavage to ca.4 when thiophilic Mn2+or Cd2+were added; thus a “rescue effect” was observed. Interestingly, the R37, R20, R25 and R51 ribozymes showed a reduced RP/SPratio of cleavage rates and much smaller “rescue effects”. This suggests that the binding of divalent metal ions in the vicinity of the phosphate group at the cleavage site is very sensitive to the overall ribozyme structure. [ABSTRACT FROM AUTHOR] more...

This paper reviews the phosphate phases in meteorites and those measured by landed spacecraft, what they reveal about past igneous and aqueous conditions on Mars, and important implications for potential prebiotic chemistry, past habitability, and potential biosignatures that could be detected in samples returned from Mars. A review of the 378 martian meteorites as of 2023 indicate that of the two most common phosphate minerals in Mars meteorites, merrillite and apatites, the apatite composition is largely F- and Cl-rich, with shergottites containing more OH. The phosphate concentrations examined across multiple missions show a relatively narrow range of phosphate, with higher concentrations observed in the Mount Sharp Group in Gale crater and Wishstone at Gusev crater and lower concentrations observed at Jezero crater floor and Jezero fan. Possible secondary phosphates detected on Mars, including Fe phosphates at Jezero crater and Gusev crater and Ca- and Al-bearing secondary phosphates, temperatures of formation of secondary phases and their dissolution rates and solubilities are reviewed and summarized. Despite this wealth of information about phosphates on Mars, due to their fine scale and relatively low concentrations, Mars Sample Return is needed to better understand phosphate and its implications for the igneous, aqueous, and astrobiological history of Mars. [ABSTRACT FROM AUTHOR] more...

Crystalline cerium(III) phosphate (CePO4), cerium(IV) phosphates, and nanocrystalline ceria are considered to be promising components of sunscreen cosmetics. This paper reports on a study in which, for the first time, a quantitative comparative analysis was performed of the UV-shielding properties of CePO4, Ce(PO4)(HPO4)0.5(H2O)0.5, and CePO4/CeO2 composites. Both the sun protection factor and protection factor against UV-A radiation of the materials were determined. Ce(PO4)(HPO4)0.5(H2O)0.5 was shown to have a sun protection factor of 2.9, which is comparable with that of nanocrystalline ceria and three times higher than the sun protection factor of CePO4. Composites containing both cerium dioxide and CePO4 demonstrated higher sun protection factors (up to 1.8) than individual CePO4. When compared with the TiO2 Aeroxide P25 reference sample, cerium(III) and cerium(IV) phosphates demonstrated negligible photocatalytic activity. A cytotoxicity analysis performed using two mammalian cell lines, hMSc and NCTC L929, showed that CePO4, Ce(PO4)(HPO4)0.5(H2O)0.5, and nanocrystalline ceria were all non-toxic. The results of this comparative study indicate that cerium(IV) phosphate Ce(PO4)(HPO4)0.5(H2O)0.5 is more advantageous for use in sunscreens than either cerium(III) phosphate or CePO4/CeO2 composites, due to its improved UV-shielding properties and low photocatalytic activity. [ABSTRACT FROM AUTHOR] more...

This paper analyses the basic obstacles preventing the fine particles from floating and suggests solutions for the wetting zone between the bubble and the particle during their collision. It has been shown in our recent paper that the basic problem of fine particle flotation is not the low frequency of collisions with the bubbles, but it consists of the efficiency of these collisions. Moreover, there exists a thermodynamic lower size limit for flotation of fine hydrophobized particles in the sub-micron range, and it is weakly dependent on the size of the bubbles. It was shown that fast flotation with high recovery of fine particles can be achieved by means of: (i) electrostatic attraction between particles and bubbles; (ii) a significant increase in the level of their hydrophobicity; (iii) existence of fine bubbles in the flotation cell. It was shown as well that the drainage of the wetting film between bubbles and particles is unimportant, but the deformation of the bubble by the particle during their clash plays a major role in its rupturing. Electrostatic attraction between bubbles and fine silica particles was achieved with hexylamine. It causes a moderate increase of their hydrophobicity from contact angle = 39.5° ± 2.5° to contact angle = 51.7° ± 7.5° and gave almost 90% recovery within 2 min. Unfortunately, the selectivity of this collector is unsatisfactory if the fine silica particles are mixed with fine magnesite particles. It was shown that even being hydrophilic, the recovery of fine particles can jump to almost 50% if strong electrostatic attraction with the bubbles exists. It was demonstrated as well with the collector hexamethyldisilazane causes significant increase of the hydrophobicity of the fine silica particles (contact angle ≈ 90°) results in skin flotation with 100% recovery when alone and 97% recovery when being mixed with fine magnesite particles (51/49). A new collector significantly increasing the hydrophobicity of magnesite fine particles was tested (disodium dodecyl phosphate) resulting in 89% recovery of fine magnesite particles alone and about 98% recovery in a mixture with fine silica particles. [ABSTRACT FROM AUTHOR] more...

Carbon steel is one of the most widely used alloys in many industries, however, its use is limited by its low corrosion resistance. Depositing a layer of phosphate on its surface improves the corrosion resistance as well as other properties, such as wear resistance, adhesion etc. Accordingly, preliminary studies demonstrated that carbon steel coated with phosphate layers can be used in the manufacture of carabiners for various fields: civil engineering, oil industry etc. Whereas, to demonstrate their capacity to operate in severe conditions related to fire rescue and extinguishing operations, it is necessary to evaluate the thermal behaviour of these materials. Thus, the main goal of this paper is to study the behaviour at high temperatures of three different types of phosphate layers deposited on carbon steel surface, by STA analysis. Also, the paper aims to study the formation of different phosphate layers by determining the types of compounds formed after the completion of the phosphating process, by XRD analysis. [ABSTRACT FROM AUTHOR] more...

In the Bohemian Massif, there are many localities with the occurrence of secondary phosphates bound to the fissures of the host rocks. The type of these rocks partly determines the character of individual phosphate associations. As part of this comprehensive work, based on the author’s PhD thesis, the main host rock types have been classified and selected mineral associations have been studied in detail. This paper is a summary not only of the author’s research, but also of the historical knowledge in the field of secondary fissure phosphates in the Bohemian Massif. The paper concludes with a brief outline of the likely conditions for the formation of fissure phosphates. [ABSTRACT FROM AUTHOR] more...

The presence of Pt(ii) allows pre-organisation of 4,4′-dicarboxamidoindole-2,2′-bipyridine, enhancing anion affinity with the resulting complex displaying selectivity for dihydrogen phosphate in DMSO-d6–0.5% water. Moreover the Pt(ii) complex behaves as a colorimetic sensor for fluoride. [ABSTRACT FROM AUTHOR] more...

This paper explores the hydrothermal treatment of α-Al2O3 powders to improve the binding in ceramic parts produced via a chemical bonding of ceramic powders combining a phosphate binder and infrared (IR) curing. Alumina powders are pre-treated in hydrothermal conditions with both water and phosphoric acid solution before slurry preparation and infrared irradiation. The effects of hydrothermal treatments on the powder's chemical reactions and the composite's final microstructure are assessed upon IR irradiation. While the water treatment does not induce any chemical changes, the presence of phosphoric acid leads to the appearance of phosphate phases Al(PO3)3 and AlPO4. Hydrothermal treatments in water and in phosphoric acid solution are found to drive faster and more intense phosphate condensation reactions at lower temperatures, with a stronger effect in the presence of H3PO4 (condensation temperature of 150 °C for the H3PO4-hydrothermal treated powder compared to 165 °C for the untreated powder). This improved reactivity of hydrothermal treatment α-Al2O3 powders, especially in the presence of H3PO4, leads to a general decrease of porosity for 3D printed parts compared to untreated alumina (for both top surfaces and cross-sections). While further optimization is needed to reduce the final porosity, it is possible to rapidly print 3D parts using this method, demonstrating a possible pathway to a single-step additive manufacturing (AM) process for ceramics. [ABSTRACT FROM AUTHOR] more...

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) are expected to be the next-generation NIR light sources, with the advantages of small size, broad bandwidth, and easy tuning of emission peaks. The key for NIR pc-LEDs is to develop highly efficient broadband NIR phosphors that can be effectively excited by blue light. Cr3+ -activated NIR phosphors have been widely studied, and this paper reviews the development of Cr3+ -doped NIR phosphors peaked at 800~900 nm. Based on phosphates, pyroxenes, and other systems, the relationships between the structure and the emission peak and bandwidth are summarized. Furthermore, to enhance the NIR performance, strategies of synthesis technology optimization, components design, and co-doping sensitizers are discussed in detail. [ABSTRACT FROM AUTHOR] more...

[Display omitted] • A low-cost, green, selective electrolysis process for Li recovery from spent LiFePO 4. • High performance LiFePO 4 was synthesised by impurity removal regeneration process. • The electrolysis and regeneration process makes full use of spent LiFePO 4. In this paper, a green, efficient and low-cost process for the selective recovery of lithium from spent LiFePO 4 by anodic electrolysis is proposed. The leaching rates of Li, Fe and P under different conditions were explored and the optimal conditions are obtained. In the optimal conditions, Li, Fe and P leaching rates were 96.31%, 0.06% and 0.62% respectively. The Li/Fe selectivity was over 99.9%. The product obtained is isostructural FePO 4 and retains the original particle morphology. The FePO 4 obtained can be synthesised into LiFePO 4 /C by direct regeneration process or impurity removal regeneration process. The material synthesized by the latter process has a better electrochemical performance, with a discharge specific capacity of 144.5 mAh/g at 1.0C and a capacity retention of 92.0% over 500cycles. The superior performance can be attributed to an impurity removal process that reduced agglomeration and improved particle morphology. [ABSTRACT FROM AUTHOR] more...

Aiming to reduce the energetic consumption and greenhouse emissions, integrating the energy-intensive dryer to a solar loop constitutes the optimum solution. This paper investigates the feasibility to integrate a bench scale flash dryer to a solar heating source. Initially, the choice of the best heating source was made and the design was realized. Then, the best configuration of the gas/liquid heat exchanger was selected to design the exchange surface. Finally, the solar flash dryer was mathematically modeled to simulate the dryer performances at various conditions. The parabolic through collectors were selected, with a nominal power of 29kWth, were coupled to a spiral finned tube exchanger with 24 kW capacity. The integration showed a significant dependency of the drying air temperature on the climatic conditions (DNI and incidence angle). The drying tests, realized at the most favorable and unfavorable conditions, showed an important decrease in the moisture fraction to be eliminated, increasing from 1.8% to 3.5% when the air temperature drops from 155 °C to 110 °C. It was hence necessary to develop a regulation system to ensure a continuous solid flow rate. [ABSTRACT FROM AUTHOR] more...

Enhancing the piezoelectric polarization strength of materials to promote the photogenerated carrier separation is of great significance for piezoelectric polarization-assisted photoelectrochemical (PEC) water splitting. In this paper, P-BiFeO3 composite photoelectrodes were synthesized by modifying BiFeO3 photoelectrodes with phosphate ions. The maximum photocurrent density of the P-BiFeO3 composite photoelectrodes could reach 0.87 mA cm−2 at 1.23 V vs RHE, which is significantly enhanced compared to the BiFeO3 photocurrent. The enhanced photoelectrochemical activity of the phosphate ion-modified BiFeO3 photoelectrodes may be attributed to the increased visible light absorption and larger active area due to the presence of phosphate groups. Furthermore, the photocurrent density of the P-BiFeO3 composite photoelectrodes after the introduction of the piezoelectric polarisation field reached 2.58 mA cm−2 at 1.23 V vs RHE, which was 2.2 times higher than that of BiFeO3 (1.17 mA cm−2). The presence of phosphate groups on the surface of BiFeO3 photoelectrodes can improve their asymmetry and increase their piezoelectric polarisation intensity, further enhancing the PEC water splitting performance of the material. This study provides a strategy for the design of highly active photoanodes with ionic modification to enhance the piezoelectric polarisation of the material to improve PEC water splitting. [ABSTRACT FROM AUTHOR] more...

This paper introduces a fast, low‐temperature, pressureless process to chemically bind ceramic parts with the help of infrared (IR) irradiation and phosphate binder condensation. Ceramic components are synthesized from slurries of ceramic powders and Al(H2PO4)3 binder that are irradiated with short‐waved IR light capable of heating the system to 350°C. This irradiation is found to be sufficient to drive phosphate condensation, binding the ceramic powders together within a matter of seconds. The IR‐irradiated components show an increase in density and Vickers hardness. Layer‐by‐layer spraying and irradiation is demonstrated as a route to additive manufacturing using various ceramic chemistries. While further optimization is needed to control desired microstructure, this process of using chemically bonded ceramic binders with IR heating for additive manufacturing shows the potential to find applications in various ceramic systems, including refractories, bone implants, electronics, and thermal barrier coatings. [ABSTRACT FROM AUTHOR] more...

This document is a correction for an article titled "Vibrio fischeri Possesses Xds and Dns Nucleases That Differentially Influence Phosphate Scavenging, Aggregation, Competence, and Symbiotic Colonization of Squid." The correction addresses specific experiments that were repeated and confirms the previous findings regarding the nuclease activity of the xds mutant strain. The timing of measurable Dns activity was found to vary slightly, but these results do not change the conclusions of the original publication. The corrected and republished paper is available for further reference. [Extracted from the article] more...

Hydroxyapatite(HA) has received more and more attention as a drug carrier due to its excellent biocompatibility and bioactivity. However, the poor biodegradability of HA, low drug loading and uncontrollable release rate limits its application. In this paper, in order to study the effect of different HA and tricalcium phosphate (β‐TCP) phase contents on the drug release performance of the composite, co precipitation template method was used to prepare the composite with different Ca/P ratios (1.5~1.63) using polystyrene colloids as templates, and the Ca/P ratio which had the greatest effect on its morphology was selected. With the ibuprofen (IBU) as the drug model, the results showed that the IBU‐loading performance of the composite was significantly better than that of the ordered‐porous pure phase HA. When the Ca/P ratio was 1.5, the composite had the highest adsorption capacity for IBU, reaching 94.5 mg/g. In vitro release tests revealed that IBU release rates from composites with different Ca/P ratios were slower than those from pure‐phase HA in the initial 10 h, and reached the release equilibrium after the subsequent 30 h. Then, when the Ca/P ratio was 1.5, the composite had a cumulative release rate of 86.35 % for IBU. The loading and slow release properties of this ordered porous HA/β‐TCP composite for IBU make it a potential candidate for controlled release of IBU in the future." [ABSTRACT FROM AUTHOR] more...

The current paper describes the results of adsorptive performance of magnetite-sulphur nanocomposite (MSNP) for the removal of phosphate which causes eutrophication; providing algae nutrients to grow at alarming rate and therefore starve other aquatic organisms of much needed oxygen. The nanocomposite was prepared by ultrasonic-heating method using sulphur and magnetite nanoparticles as starting materials in the presence of citric acid as stabilising agent. Formation of nanocomposite was verified by FTIR, SEM, EDX, TEM, UV-Vis, XRD, TGA and pH of point of zero charge measurements. Adsorptive removal of phosphate by the nanocomposite was investigated in aqueous solution by determining the effects of catalyst dosages, contact time, phosphate initial concentrations and pH of the solution on phosphate adsorption. The results indicated that phosphate uptake reached maximum adsorption capacity at 38.58 mg/g, corresponding to pH 4.5, suggesting that acidic conditions favour removal of phosphate ions in water. Adsorption process was consistent with both Langmuir isotherm model and pseudo-second order. The calculated parameters from Langmuir model and pseudo-second order showed that the phosphate adsorption on MSNP is a feasible process. Adsorption mechanism was attributed to bimolecular interactions involving anionic species of phosphate and cationic sites of MSNP. The spent MSNP was easily regenerated with NaOH and reused for more than four adsorption-desorption cycles. The adsorbent showed good reusability and therefore suitable for phosphate removal and other water contaminants. [ABSTRACT FROM AUTHOR] more...

Evanescent wave optical fibre sensors have attracted a lot of attention for the detection of chemical species due to their sensitivity, selectivity, and repeatability. In addition, plastic optical fibre sensors are inexpensive, simple to fabricate, and not only act as sensors, but the same fibre can also be used to transport sensor signals. The fibre sensor's sensitivity can be increased by removing the fibre cladding partially or fully. Also, different geometries have been reported to enhance the sensitivity of fibre sensors even more. In this paper, we report a U-shaped optical fibre sensor that utilises evanescent wave absorption as its primary mechanism for determining phosphate concentration in water. The U-shaped geometry offers enhanced sensitivity as compared to straight geometry. The developed U-shaped plastic optical fibre probe demonstrates impressive linear performance, which is evident in its remarkable regression coefficient of 98.48% and sensitivity of 0.0991 O.D./ppm. Due to their distinct features, plastic optical fibre sensors pave the way for improved water quality monitoring and analysis, which presents a vital contribution to both the industrial and environmental domains. [ABSTRACT FROM AUTHOR] more...

The oxygen isotope ratio of phosphates is a powerful tool to study phosphorus in the soil‐plant system. In the past two decades, the scientific community has made substantial progress in characterizing biogeochemical processes that lead to an alteration of oxygen isotope ratios in phosphates and in evaluating oxygen isotope ratios of phosphates in plants and soils under various environmental conditions around the globe. However, there are still uncertainties with respect to their interpretation in environmental systems. These uncertainties include the comprehensive analysis of isotope endmembers, artifacts during the chemical extractions and the phosphate purification protocols, overlapping isotope values from various processes and sources, gaps of knowledge about isotope effects of metabolic pathways, and the possibly erroneous assumption that insights from experiments under controlled laboratory conditions can be directly translated into the complex soil‐plant system. This paper provides a critical discussion of these uncertainties addressing recommendations and needs for future research and gives an outlook on recent technological advances, such as triple oxygen isotope analysis or the use of high‐resolution mass spectrometry. We conclude by suggesting that a concerted and systematic effort by scientists from a wide range of disciplines will be necessary to remove the uncertainties in the interpretation of oxygen isotope ratios in phosphates as an environmental tracer. [ABSTRACT FROM AUTHOR] more...