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The objective of this work to review about interaction of different food additives with Haemoglobin (Hb) and Myoglobin (Mb) proteins. Food additives are the important components which are added in food to preserve its flavour, color, appearance along with its taste. Mb and Hb interacts with numerous food dyes at varying conditions. In this study we will use various spectroscopic techniques like fluorescence spectroscopy, UV–Visible spectroscopy, Rayleigh light scattering (RLS), fluorescence resonance energy transfer (FRET), circular dichroism (CD)alongwithtransmissionelectronmicroscopy (TEM)andmoleculardockingtocharacterize the binding consequences of Mb and Hb. Proteinaggregationisthedistinctivepropertyrelatedtohumanbody. Deformationofprotein along with its aggregation leads to vast conformational change in human body and leads to several blood related (anemia, leukemia) andneurodegenerativediseaseslikeParkinson’sandAlzheimer’s. Foodadditivesaretoxictohumansaswellastoenvironment. Sothe aim of this study to find out the methods for detection of such diseases along with its cure as well as methods to release these toxic dyes via interaction of additives with Hb & Mb.

In this study we report a facile, cost effective one step preparation method for the synthesis of Mn doped cerium oxide (CeO2) nanoparticles (NPs) through co-precipitation technique. The synthesis was performed at relatively low temperature using a green reagent oxalic acid as reducing agent. The structural and optical attributes of the samples were characterized by X-Ray Diffraction spectroscopy (XRD), Fourier Transform Infrared Spectroscopy (FTIR), UV–Visible spectroscopy and SEM (Scanning electron microscopy). The XRD and FTIR results show the formation of Mn doped ceria NPs having a cubic fluorite structure. The morphology and chemical composition of the prepared sample was realized using SEM and EDX spectrum. The synthesized Mn doped ceria NPs shows greater absorption in the visible region and reduced particle size compared to pure ceria NPs.

Pulmonary fibrosis (PF) is an irreversible lung disease that is characterized by excessive scar tissue with a poor median survival rate of 2–3 years. The inhibition of TGF-β receptor type-I (TGF-β RI) by an appropriate drug may provide a promising strategy for the treatment of this disease. Polygonum cuspidatum (PC) is a well-known traditional Chinese herbal medicine which has an anti-PF effect. Accordingly, a combination of high resolution mass spectrometry and an in silico strategy was developed as a new method to search for potential chemical ingredients of PC that target the TGF-β RI. Based on this strategy, a total of 24 ingredients were identified. Then, absorption, distribution, metabolism, and excretion (ADME)-related properties were subsequently predicted to exclude compounds with potentially undesirable pharmacokinetics behaviour. Molecular docking studies for TGF-β RI were adopted to discover new PF inhibitors. Eventually, a compound that exists in PC known as resveratrol was proven to have excellent biological activity on TGF-β RI, with an IC50 of 2.211 μM in vitro. Furthermore, the complex formed through molecular docking was tested via molecular dynamics simulations, which revealed that resveratrol had strong interactions with residues of TGF-β RI. This study revealed that resveratrol has significant potential as a treatment for PF due to its ability to target TGF-β RI. In addition, this research demonstrated the exploration of natural products with excellent biological activities toward specific targets via high resolution mass spectrometry in combination with in silico technology is a promising strategy for the discovery of novel drugs.

We investigated the growth and electronic properties of Co-phthalocyanine (CoPc) molecule deposited on iron film with different structures (pseudomorph-fcc and bcc) and on iron nanowires by scanning tunnelling microscopy and X-ray absorption spectroscopy (XAS). CoPc molecules self-assemble in a two-dimensional (2D) arrangement with the molecular plane parallel to the iron surfaces, and the local order is lost after the first layer. The molecule ferromagnet interaction causes the broadening of Co and N unoccupied molecular states as well as different electronic distribution of N states as a function of the atomic structure of iron surface. The ferromagnetic coupling between the molecule and the iron film is dominated by the electronic interaction between Co and the first Fe layer. CoPc 2D arrangement turns into 1D by using as a template the iron nanowire grown on a facet surface of oxidized Cu(332) surface. CoPc molecules interact weakly with the iron nanowires manifesting a substantial Co 3d(z) spectral feature in XAS spectrum and the possibility of a magnetic interaction between Co moment and iron nanowires. Both CoPc 2D and 1D arrangements can open up new interesting scenarios to tune the magnetic properties of hybrid interfaces involving metallorganic molecules.

International audience; The cyanobacterium Arthrospira platensis, spirulina, is a source of pigments such as phycobiliprotein, phycocyanin. Phycocyanin is used in the food, cosmetic, and pharmaceutical industries because of its antioxidant, anti-inflammatory, and anticancer properties. The different steps involved in extraction and purification of this protein can alter the final properties. In this review, the stability of phycocyanin (pH, temperature, and light) is discussed, considering the physicochemical parameters of kinetic modeling. The optimal working pH range for phycocyanin is between 5.5 and 6.0 and it remains stable up to 45 °C; however, exposure to relatively high temperatures or acidic pH decreases its half-life and increases the degradation kinetic constant. Phycobiliproteins are sensitive to light and preservatives such as mono- and di-saccharides, citric acid, or sodium chloride appear to be effective stabilizing agents. Encapsulation within nano- or micro-structured materials such as nanofibers, microparticles, or nanoparticles, can also preserve or enhance its stability.

Amperometric nanobiosensors are crucial time and cost effective analytical tools for the detection of a wide range of bioanalytes, viz. glucose present in complex environments at very low concentrations. Although the excellent analytical performance of nanobiosensors is undoubted, their exact molecular structure often remains unclear. Here, by combining advanced nanoanalytical approaches with theoretical modeling, we conducted a comprehensive study towards the investigation of the molecular structure of a hybrid GOx/Nafion/Pd-NPs layer deposited by electroplating from the multicomponent electrolyte solution on the surface of screen printed electrodes modified with graphene oxide. Specifically, we revealed that Pd2+ cations were adsorbed on GOx amino acid residues, forming the GOx·nPd2+ enzymatic complex. The highest adsorption energy of Pd2+ cations on GOx was found during their interaction with the side chains of basic amino acids and methionine. In addition, we showed and fully validated the end-structure of the one-step designed GOx/Nafion/Pd-NPs nanobiosensor as a structural model mainly composed of GOx and water molecules incorporated into the metal-polymer scaffold. Our approach will thus serve as a guideline for the study of molecular interactions occurring in complex systems and will contribute to the design of the next generation of hybrid nanobiosensors. The proposed mechanism, driving the self-assembly of the hybrid layer, will allow us to construct modular enzymatic nanoanalytical devices with tailored sequences in the future.

Monazite ((Ce, La)PO4) is one of the major types of light rare earth minerals from which the light rare earth elements cerium (Ce) and lanthanum (La) are economically extracted. Flotation is extensively used to recover fine-grained monazite. Sodium oleate (NaOL) is considered as the collector with the strong collecting ability for monazite flotation. However, this study shows that its collecting ability is still limited. In this paper, a phosphonic acid, nonane-1,1-bisphosphonic acid (C9-BPA), was employed as the novel collector in place of NaOL. Flotation experiments show that even when the C9-BPA dosage is less than one-fifth of the NaOL dosage, the monazite recovery using C9-BPA as the collector is approximately 22 wt% higher than that using NaOL. The mechanism by which C9-BPA adsorbs on monazite was investigated using zeta potential, infrared (IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements as well as first-principles calculations. Zeta potential measurements show a more significant decrease in the zeta potentials of monazite after the addition of C9-BPA compared to those after the addition of NaOL. For C9-BPA-treated monazite, the characteristic peaks of C9-BPA were observed in the IR and C 1s XPS spectrum, whereas for monazite treated by NaOL, no characteristic peak of NaOL was observed. Experimental results show that C9-BPA has a stronger affinity towards the monazite surface than NaOL as confirmed by the higher adsorption energy of CP-BPA on the monazite surface (‒204.22 kJ/mol) than NaOL (‒48.48 kJ/mol). This study demonstrates an extensive application value and prospect of C9-BPA in monazite flotation and helps design novel collectors with strong collecting ability for monazite flotation.

Rotundic acid (RA), an ursane-type pentacyclic triterpene acid isolated from the dried barks of Ilex rotunda Thunb. (Aquifoliaceae), possesses diverse bioactivities. To further study its pharmacokinetics, a simple and sensitive liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS/MS) method was developed and validated to quantify RA concentration in rat plasma and tissue using etofesalamide as an internal standard (IS). Plasma and tissue samples were subjected to one-step protein precipitation. Chromatographic separation was achieved on a ZORBAX Eclipse XDB-C18 column (4.6 mm × 50 mm, 5 μm) under gradient conditions with eluents of methanol:acetonitrile (1:1, V/V) and 5 mM ammonium formate:methanol (9:1, V/V) at 0.5 mL/min. Multiple reaction monitoring transitions were performed at m/z 487.30 → 437.30 for RA and m/z 256.10 → 227.10 for IS in the negative mode. The developed LC-QqQ-MS/MS method exhibited good linearity (2–500 ng/mL) and was fully validated in accordance with U.S. Food and Drug Administration bioanalytical guidelines. Dose proportionality and bioavailability in rats were determined by comparing pharmacokinetic data after single oral (10, 20, and 40 mg/kg) and intravenous (10 mg/kg) administration of RA. Tissue distribution was studied following oral administration at 20 mg/kg. The results showed that the absolute bioavailability of RA after administration at different doses ranged from 16.1% to 19.4%. RA was rapidly absorbed in a dose-dependent manner and highly distributed in the liver. In conclusion, this study is the first to systematically elucidate the absorption and distribution characteristics of RA in rats, which could provide additional information for further development and evaluation of RA in drug metabolism and pharmacokinetic studies.

A fast, reliable, and cost-effective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established to determine the effects of the traditional Chinese medicine employed to treat coronavirus disease 2019, namely, Lianhua Qingwen granules, Huoxiang Zhengqi capsules, Jinhua Qinggan granules, Shufeng Jiedu capsules, and Angong Niuhuang pills, on the pharmacokinetic of lopinavir/ritonavir in rats. Blood samples were prepared using the protein precipitation method and atazanavir was selected as the internal standard (IS). Separation was performed on an Agilent ZORBAX eclipse plus C18 (2.1 mm × 50 mm, 1.8 μm) column using acetonitrile and water containing 0.1% formic acid as the mobile phase for gradient elution. The flow rate was 0.4 mL/min and the injection volume was 2 μL. Agilent Jet Stream electrospray ionization was used for mass spectrometry detection under positive ion multiple reaction monitoring mode at a transition of m/z 629.3 → 447.3 for lopinavir, m/z 721.3 → 296.1 for ritonavir, and m/z 705.4 → 168.1 for the IS. The method showed good linearity in the concentration range of 25–2500 ng/mL (r = 0.9981) for lopinavir and 5–500 ng/mL (r = 0.9984) for ritonavir. The intra-day and inter-day precision and accuracy were all within ±15%. Items, such as dilution reliability and residues, were also within the acceptable limits. The method was used to determine the effects of five types of traditional Chinese medicine on the pharmacokinetics of lopinavir/ritonavir in rats. The pharmacokinetic results showed that the half-life (t1/2) of ritonavir in the groups administered Lianhua Qingwen granules and Huoxiang Zhengqi capsules combined with lopinavir/ritonavir was prolonged by approximately 1.5–2-fold relative to that in the control group. Similarly, the pharmacokinetic parameters of lopinavir were altered. Overall, the results of this study offer important theoretical parameters for the effective clinical use of five types of traditional Chinese medicine combined with lopinavir/ritonavir to reduce the occurrence of clinical adverse reactions.

Inducible T-cell costimulator (ICOS) is a homodimeric protein expressed on the surface of activated T-cells that is being investigated as a potential therapeutic target to treat various cancers. Recent studies have reported aberrant increases in the soluble form of ICOS (sICOS) in human serum in disease-state patients, primarily using commercial ELISA kits. However, results from our in-house immunoassay did not show these aberrant increases, leading us to speculate that commercial sICOS ELISAs may be prone to interference. We directly tested that hypothesis and found that one widely used commercial kit yields false-positives and is prone to human anti-mouse antibody (HAMA) interference. We then analyzed a panel of healthy, cancer, chronic hepatitis C virus, systemic lupus erythematosus, and diffuse cutaneous systemic sclerosis human serum using our in-house immunoassay and reported the measured sICOS concentrations in these populations. Since even well characterized immunoassay methods are prone to non-specific interference, we also developed a novel sICOS LC-MS/MS method to confirm the results. Using these orthogonal approaches, we show that sICOS is a low abundance soluble protein that cannot be measured above approximately 20 pg/mL in human serum.

Indole-3-carbinol (I3C), an important anticancer compound found in broccoli, has attracted considerable attention. The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature. In this study, a rapid, accurate, and low-cost ultrasound-assisted dispersive-filter extraction (UADFE) technique based on poly(deep eutectic solvent)-graphene oxide (PDES-GO) adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time. PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption. UADFE was developed by combining dispersive solid-phase extraction (DSPE) and filter solid-phase extraction (FSPE) to realize rapid extraction and separation. Based on the above two strategies, the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography (HPLC) allowed the rapid (15–16 min), accurate (84.3–96.4%), and low-cost (adsorbent: 3.00 mg) analysis of I3C in broccoli and was superior to solid-phase extraction, DSPE, and FSPE methods. The proposed method showed remarkable linearity (r=0.9998; region: 0.0840–48.0 μg/g), low limit of quantification (0.0840 μg/g), and high precision (relative standard deviation ≤ 5.6%). Therefore, the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples.

Structural, optical and magnetic properties are reported for new synthesized perovskite materials. Ba0.3La0.7Ti0.3Fe0.7O3 and Ba0.1La0.9Ti0.1Fe0.9O3 compositions were prepared via solid state reaction. X-ray analysis confirms that both compositions show feature of perovskite structure. Rietveld refinement method was used to confirm the phase formation and investigate the structure and space group. The study demonstrates the formation of orthorhombic structure with Pnma space group for Ba0.3La0.7Ti0.3Fe0.7O3 while the composition Ba0.1La0.9Ti0.1Fe0.9O3 structure adopts Pbnm symmetry. UV-vis spectroscopy measurements show very broad and intense UV-visible light absorption, the estimated band gap ranges between 2.07 and 2.15 eV. Magnetic measurements were carried out for the compositions Ba0.3La0.7Ti0.3Fe0.7O3 and Ba0.1La0.9Ti0.1Fe0.9O3. The hysteresis loop of both samples at 300 and 10 K show a strong ferromagnetic behavior. The temperature dependent magnetization at 0.05 T under field-cooled (FC) and zero field cooled (ZFC) modes shows magnetic frustration or spin glass-like behavior.

Blighia sapida (B. sapida) K.D. Koenig (Family Sapindaceae) is a branchless straight bole approximately 15 m long. The study evaluated the antioxidant and anti-inflammatory activities of ethanol extract and fractions of B. sapida stem-bark using in vitro methods. Ethanol extract and its fractions were investigated for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power (FRAP), total antioxidant capacity (TAC), and quantitative phenolic and flavonoid contents. Anti-inflammatory activity was evaluated using albumin denaturation and membrane stabilization assays. The extract and its fractions exhibited radical scavenging and anti-inflammatory properties. The ethyl acetate fraction possessed maximum phenolic and flavonoid contents (136.67 ± 1.55 gallic acid mg/g and 75.76 ± 4.03 quercetin equivalent mg/g, respectively). Antioxidant studies revealed that the ethyl acetate fraction displayed superior activity with an IC50 = 0.09 ± 0.03 mg/mL DPPH, and values of 146.96 ± 3.81 and 359.20 ± 4.98 for FRAP and TAC respectively. Furthermore, the anti-inflammatory activity was revealed by inhibition of heat-induced albumin denaturation and red blood cell membrane stabilization at concentrations of 200-1000 μg/mL and 50-250 μg/mL, respectively. The ethanol extract and fractions exhibited antioxidant and anti-inflammatory activities, with ethyl acetate fraction showing superior activity, which could be attributed to secondary metabolites, mainly phenolic compounds. Overall, the antioxidant and anti-inflammatory activities of B. sapida can be exploited by ethnomedicinal users.

l -kynurenine (L-kyn) is a marker of prostate cancer. At present, the expensive instruments are usually applied to detect L-kyn in clinically, which limits its wide application for cancer diagnosis. Herein, three lanthanide metal–organic frameworks ([Ln(CHO2)3]n, Ln = Eu, Gd, and Tb) were designed and obtained, and detailly characterized by single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and luminescence spectroscopy. Further study reveals that [Tb(CHO2)3]n is a highly selective, ultra-sensitive, of strong anti-interference, highly stable, and non-expensive sensor for prostate cancer marker L-kyn. The limit of detection (LOD) for L-kyn sensing is a highly sensitive value of 1.0 × 10−9 mol/L. Furthermore, the sensing mechanism is discussed in detail.

The present paper deals with the physiological response of the changes in chemical contents in the root, stem and leaf of Vetiveria zizanioides seedlings stressed by excess cadmium using Fourier transform infrared spectroscopy technique. Cadmium accumulation in plant and distribution in subcellular by atomic absorption spectroscopy were tested under different concentrations cadmium stress. The results show that low cadmium concentrations (

Selective and efficient electrochemical analytical methods for the characterization of the corrosion behavior of beryllium bronze alloys are significant and necessary. These electrochemical methods are based on open-circuit chronopotentiometry curves, potentiodynamic polarization, and electrochemical impedance spectroscopy. From the electrochemical analysis, the results show that the corrosion reaction of the untreated samples became more severe as the NaCl concentration was increased. However, the corrosion reaction was not obvious when the alloy was treated by commercial latex paint and laboratory-produced latex paint. Furthermore, the corrosion potential has same variation tendencies and the value of the corrosion potential was more positive when the alloy surface was treated by the laboratory-produced latex paint. The maximum and minimum of the corrosion potential were found for conditions using the untreated samples and samples treated with the laboratory-produced latex paint. The corrosion c...

Natural long-chain alkanol and alkyl carboxylic acid were used to prepare novel hydrophobic deep eutectic solvents (HDESs). These HDESs are liquid at room temperature and have low viscosity (12.26 mPa‧s), low polarity (lower than that of methanol, ChCl-based deep eutectic solvents and other reported HDESs), and low density (0.928 g/mL). A simple one-pot method based on a novel HDES-water two-phase extraction system was constructed for the extraction of weak-polarity bioactive components, anthraquinones, from Rhei Radix et Rhizoma. This HDES-based new extraction method does not consume hazardous organic solvents and can obtain a total anthraquinone yield of 21.52 mg/g, which is close to that obtained by the Chinese pharmacopoeia method (21.22 mg/g) and considerably higher than those by other reported HDESs-based extraction methods (14.20-20.09 mg/g

Nanosized probes that report their changes in dimensions within networks in response to environmental stimuli are potentially important for applications such as drug delivery, load-supporting hydrogels and soft robotics. Recently, we developed a fluorescent pH-responsive nanogel (NG) that used Forster-resonance energy transfer (FRET) to report changes in the probe separation and NG swelling within hydrogels using photoluminescence (PL) spectroscopy. However, FRET cannot measure nanoparticle dimensions and is subject to artefacts. Here, we report the use of small-angle neutron scattering (SANS) to study both the NGs in dispersion and in polyacrylamide (PAAm) gels as a function of pH. We compare the PL and SANS data for both systems and as a function of pH. The SANS data for the dispersed NGs indicate that they have a core–shell structure with a swollen mesh size of ∼1.0 nm. We hypothesized that the NGs inside the PAAm gel would show the same general changes in scattering as the pH is increased, as observed for the dispersed NGs, and this is confirmed by the data. In summary, the data confirm that PL is a suitable (accessible) method for reporting internal environmental changes within gels using NG probes.

The phase equilibria of the Mg–Ag–Cu ternary system at 350 and 400 °C were experimentally investigated using twenty-eight key samples. The phase equilibria and compositions in key samples were investigated using scanning electron microscopy (SEM) equipped with energy-dispersive spectroscopy (EDS). Powder X-ray diffraction (XRD) technique was used to analyze the crystal structure and solid solubility of compounds. Five three-phase equilibria and several two-phase equilibria have been determined at 350 and 400 °C. The solid solubility range of Cu in the compounds Mg3Ag, MgAg and fcc(Ag) were examined at 350 and 400 °C. The maximum solid solubility of Ag in the compound MgCu2 was found to be 11.46 at.% and 11.25 at.% with a constant value of about 66 at.% Cu at 350 and 400 °C, respectively. Besides, the solid solubility limits of Ag in the compounds Mg2Cu and fcc(Cu) were found to be less than 5 at.% at 350 and 400 °C. No ternary compound was observed in the present work.

A mixed drug self-delivery system (DSDS) with high drug content (>50%) was developed to regulate pH-triggered drug release, based on two doxorubicin (DOX)-DOX dimmers: D-DOXADH and D-DOXcar conjugated with acid-labile dynamic covalent bonds (hydrazone and carbamate, respectively) and stabilized with PEGylated D-DOXADH (D-DOXADH-PEG). Owing to the different stability of the dynamic covalent bonds in the two dimers and the noncovalent interaction between them, pH-triggered drug release could be easily regulated by adjusting the feeding ratios of the two DOX-DOX dimers in the mixed DSDS. Similar in vitro cellular toxicity was achieved with the mixed DSDS nanoparticles prepared with different feeding ratios, that had a similar DOX content and diameter but different drug releasing rates. The MTT assays revealed that a high anti-tumor efficacy could be achieved with the slow-release mixed DSDS nanoparticles.

Chromium is a harmful contaminant showing mutagenicity and carcinogenicity. Therefore, detection of chromium requires the development of low-cost and high-sensitivity sensors. Herein, blue-fluorescent carbon quantum dots were synthesized by one-step hydrothermal method from alkali-soluble Poria cocos polysaccharide, which is green source, cheap and easy to obtain, and has no pharmacological activity due to low water solubility. These carbon quantum dots exhibit good fluorescence stability, water solubility, anti-interference and low cytotoxicity, and can be specifically combined with the detection of Cr(VI) to form a non-fluorescent complex that causes fluorescence quenching, so they can be used as a label-free nanosensor. High-sensitivity detection of Cr(VI) is achieved through internal filtering and static quenching effects. The fluorescence quenching degree of CDs fluorescent probe showed a good linear relationship with Cr(VI) concentration in the range of 1–100 μM. The linear equation was F0/F = 0.9942 + 0.01472[Cr(VI)] (R2 = 0.9922), and the detection limit can be as low as 0.25 μM (S/N = 3), which has been successfully applied to Cr(VI) detection in actual water samples herein.

Hyperpolarized nuclear magnetic resonance and lab-on-a-chip microfluidics are two dynamic, but until recently quite distinct, fields of research. Recent developments in both areas increased their synergistic overlap. By microfluidic integration, many complex experimental steps can be brought together onto a single platform. Microfluidic devices are therefore increasingly finding applications in medical diagnostics, forensic analysis, and biomedical research. In particular, they provide novel and powerful ways to culture cells, cell aggregates, and even functional models of entire organs. Nuclear magnetic resonance is a non-invasive, high-resolution spectroscopic technique which allows real-time process monitoring with chemical specificity. It is ideally suited for observing metabolic and other biological and chemical processes in microfluidic systems. However, its intrinsically low sensitivity has limited its application. Recent advances in nuclear hyperpolarization techniques may change this: under special circumstances, it is possible to enhance NMR signals by up to 5 orders of magnitude, which dramatically extends the utility of NMR in the context of microfluidic systems. At the same time, hyperpolarization requires complex chemical and/or physical manipulations, which in turn may benefit from microfluidic implementation. In fact, many hyperpolarization methodologies rely on processes that are more efficient at the micro-scale, such as molecular diffusion, penetration electromagnetic radiation into the sample, or restricted molecular mobility on a surface. In this review we examine the confluence between the fields of hyperpolarization-enhanced NMR and microfluidics, and assess how these areas of research have mutually benefited one another, and will continue to do so., Comment: 63 pages, 21 Figures

The structure, chemical bonding and photoemission of amorphous hydrogenated silicon carbonitride (a-SiCN:H) films deposited by plasma-enhanced chemical vapor deposition (PECVD) using hexamethyldisilazane as a main precursor at different hydrogen flow rates are studied. Film properties are characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), absorption optical spectra and photoluminescence (PL). The photoluminescence spectra were presented by four photoemission bands centered at 441–451, 489–496, 530–535 and 577–601 (in nm). To explain structural and photoluminescence properties of the deposited films, first-principles molecular dynamics simulations of un-hydrogenated and hydrogenated silicon carbonitride samples were carried out. Based on experimental and theoretical results a possible explanation of the photoemission of the deposited films and its evolution with increasing hydrogen flow rate was done.

In the present work gold nanoparticles were synthesized by green method using Aegle marmelos bark extract and the reaction conditions were optimized. Synthesized nanoparticles were characterized by using different analytical techniques including UV–Visible spectroscopy, FTIR (Fourier Transform Infra Red) spectroscopy, TEM (Transmission electron microscopy), DLS (Dynamic Light Scattering) and Zeta Potential Analyser. The Biosynthesized gold nanoparticles were then used for colorimetric detection of Cr(III) and Al(III) from aqueous medium. It was found that the detection limit with nanoparticles was as low as 0.5 mM for Cr(III) ion and 0.01 mM for Al(III) ions in aqueous medium.

The application of azimuthal plot analysis of tts-μXRD results allows us to discriminate the origin of calcium oxalate nephrolith formation.

A series of 6-oxo verdazyl radicals functionalised at the 1- and 5-positions by methyl, thiomethyl and iodo groups were synthesised using conventional strategies. Facile Sonogashira cross-coupling reactions of terminal alkynes with the diiodo analogue were used for synthetic elaboration of the verdazyl core structure with π-conjugated ethynyl groups. The radicals were characterised by EPR spectroscopy, single-crystal X-ray diffraction, cyclic voltammetry and optical spectroscopy. The chemically and electrochemically reversible oxidation and reduction of these radicals within a convenient redox window permitted further studies on the closed-shell cationic and anionic forms using spectroelectrochemical methods, supported by (TD-)DFT calculations.

Mn-Ni co-doped ZnO thin films (Zn0.98Mn0.01Ni0.01O) were synthesized on glass via sol–gel spin coating approach. The effect of substrate rotation speed was investigated on structural, optical, topographical, and vibrational characteristics of thin films. XRD, SEM, Raman spectroscopy, ultraviolet–visible spectroscopy, and photoluminescence spectroscopy were utilized for the characterization of the films. The size of crystallite has decreased by raising the rotation speed of substrate. The surface of all thin films shows uniformly distributed grains of size ranging 22.41 nm to 19.74 nm. Raman spectra show characteristic hexagonal wurtzite structure peak of ZnO at 429 cm−1 corresponding to E2(High) optical phonon mode. The energy gap changed from 3.275 eV to 3.256 eV with rising substrate rotation speed. The photoluminescence spectra showed UV, violet, green, yellow, and red emission for all thin films. The ultraviolet peak was red-shifted on increasing substrate rotation speed. So, optical properties can be tailored by changing the rotation speed of substrate and utilized in optoelectronic devices.

A new metal-oxo-clusters-based inorganic framework [NaCo2Mo2O7(OH)3]n (NaCoMo), named as 3D platelike ternary-oxo-cluster, has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction structure analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) analyses, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). Structure analysis reveals that there are no classical building units in NaCoMo, and the asymmetric units of NaCoMo are directly extended into a new platelike 3D structure. Density functional theory calculations (DFT) indicates that the crystal formation process is exothermic and the structure is extremely stable. In addition, the compound presents excellent catalytic activity in the condensation and cyclization reaction of sulfonyl hydrazides and 1,3-diketones to synthesize pyrazoles, and the yield of the desired product is up to 99%. The successful synthesis of NaCoMo represents the discovery of a new kind of non-classical polyoxometalates.

Nd3+ doped TiO2 and undoped TiO2 were produced by the complication free hydro thermal synthesis process. The doping has reduced the bandgap of the tailored material compared to its purest form. The UV–vis spectroscopy and Photo Fluorescence spectroscopy are employed to study the characteristics of the synthesized material and the results drawn from the characterization vouch that the gap between the CB and VB has minimized. The absorption peak calculated using the spectro-flourometer asserts that Nd3+ doped TiO2 can be utilized well in the UV-A and UV-B regions along with the visible region of the solar light. This expansion in the area will enhance the efficiency of the solar cells.

The quantitative understanding of how atomic-level catalyst structural changes affect the reactivity of the electrochemical CO2 reduction reaction is challenging. Due to the complexity of catalytic systems, conventional in situ X-ray spectroscopy plays a limited role in tracing the underlying dynamic structural changes in catalysts active sites. Herein, operando high-energy resolution fluorescence-detected X-ray absorption spectroscopy was used to precisely identify the dynamic structural transformation of well-defined active sites of a representative model copper(II) phthalocyanine catalyst which is of guiding significance in studying single-atom catalysis system. Comprehensive X-ray spectroscopy analyses, including surface sensitive Δμ spectra which isolates the surface changes by subtracting the disturb of bulk base and X-ray absorption near-edge structure spectroscopy simulation, were used to discover that Cu species aggregated with increasing applied potential, which is responsible for the observed evolution of C2H4. The approach developed in this work, characterizing the active-site geometry and dynamic structural change, is a novel and powerful technique to elucidate complex catalytic mechanisms and is expected to contribute to the rational design of highly effective catalysts.

Yb doped ZnO nanorods were prepared on glass substrates by the hydrothermal method in order to investigate the insertion of Yb ions in the ZnO matrix and the related morphological, structural and vibrational properties of the samples. X-ray diffraction patterns showed that the undoped and Yb doped ZnO nanorods exhibit the hexagonal wurtzite crystal structure with a preferential orientation along (1 0 1) direction and the size of the particle is found to be decreased with Yb content. SEM images show rods shape with more agglomeration in Yb doped ZnO nanorods. The vibrational study has also been performed using FT-IR spectroscopy which gives the presence of an absorption band corresponding to the stretching mode frequency of ZnO (Zn−O), the bands corresponding to organic precursors were no longer present in the FTIR spectrum after doping, which supports the incorporation of Yb ions into the ZnO lattice. Raman spectra confirmed the hexagonal wurtzite structure of pure and Yb doped ZnO nanoparticles with E2 (high) mode at 438 cm−1 and the presence of other possible defects. The aim of this study was to investigate the effect of Yb doping on the structural and vibrational properties of ZnO nanorods.

Pristine Cadmium Sulphide (CdS) and Polyvinylpyrrolidone (PVP) capped CdS nanoparticles have been synthesized by co-precipitation method. X-ray diffraction (XRD) analysis reveals that the CdS nanoparticles have a hexagonal structure. Field emission scanning electron microscopy (FESEM) with Energy dispersive x-ray spectroscopy (EDX) have been employed to study morphology and elemental composition for the prepared samples. From FESEM images, the average particle size of nanostructures is found to be 23.6 nm for PVP capped CdS and 16.2 nm for pristine CdS. Absorption spectroscopy reveals that the bandgap of 2.48 eV and 2.23 eV for pure CdS and PVP capped CdS nanoparticles respectively. Fourier transforms infrared (FTIR) spectroscopy provides information about the functional groups present in the samples. Out of these two samples, CdS nanoparticles with PVP polymer have been used as a gas sensing application at room temperature for various gases like N2, NH3, O2, and Ar because it shows the better properties than the pure CdS nanoparticles.

The main factor restricting lead isotope analysis of metals from museum collections is the requirement for physical material. Hence, there are major incentives for developing minimally invasive methods for lead isotope analysis that are accurate and precise enough to reveal historical information about artefacts and their origin. Portable laser ablation (pLA), collecting microscopic samples on Teflon filters, has four key benefits. It produces no visual impact to the artefacts, does not require transport of artefacts to laboratory facilities, there are no artefact size restrictions, and samples are processed under clean laboratory conditions allowing Pb purification prior to measurement by solution MC-ICPMS. To validate the efficacy of the pLA technique on silver, nine matrixed-matched commercial, in-house and archaeological reference materials were sampled and analysed multiple times (9-10). The pLA mean analyses (±2SD) were all consistent with inter-laboratory bulk analyses. The digestion of sample filters produces precisions that are consistently more than five-times better than in situ nsLA-MC-ICPMS and are the same order of magnitude expected for bulk samples processed in different laboratories. This journal is

The dynamical complexity of the hydrogen-bonded water network can be investigated with intense Terahertz (THz) spectroscopy, which can drive the liquid into the nonlinear response regime and probe anharmonicity effects. Here we report single-color and polarization-dependent pump–probe experiments at 12.3 THz on liquid water, exciting the librational mode. By comparing results obtained on a static sample and a free-flowing water jet, we are able to disentangle the distinct contributions by thermal, acoustic, and nonlinear optical effects. We show that the transient transmission by the static water layer on a time scale of hundreds of microseconds can be described by thermal (slow) and acoustic (temperature-dependent) effects. In addition, during pump probe overlap we observe an anisotropic nonlinear optical response. This nonlinear signal is more prominent in the liquid jet than in the static cell, where temperature and density perturbations are more pronounced. Our measurements confirm that the THz excitation resonates with the rotationally-damped motion of water molecules, resulting in enhanced transient anisotropy. This model can be used to explain the non-linear response of water in the frequency range between about 1 and 20 THz.

Green synthesis using soluble starch as stabilizing agent in aqueous medium is an approach towards to develop an eco friendly method for synthesis of nanoparticles. It has advantages over conventional method involving toxic reagents. Cadmium sulfide is a suitable material among the II-VI compounds for optoelectronic and solar applications. We report a study on the optical properties of CdS nanocrystals prepared by green synthesis method. Cadmium sulfide nanoparticles were prepared using starch as stabilizing agent. The sample was characterized by X-ray diffraction, Scanning electron microscope, UV–Visible absorption spectroscopy, and photoluminescence spectroscopy. From the study, the blue shift in absorption wavelength with respect to bulk CdS indicate the increased in effective energy band gap and formation of nano sized CdS particles. The estimated size confirms the weak confinement regime as the size comparable to exciton Bohr radius. Photoluminescence spectrum shows band edge emission and deep trap states emission. The CdS nanoparticles exhibit photo catalytic activity against methyl orange under visible light irradiation. The 75% photo degradation was observed for 90 min irradiation time.

International audience; The double isotope dilution is a powerful methodology to measure accurately the ratio between two isotopes of two different elements (e.g. 238Pu/238U, 148Nd/238U or 230Th/238U ratios). To obtain the lowest possible uncertainty, some parameters must be optimized: the elaboration of the spike and the proportion of the spike in the sample - spike mixture. A piece of code is provided to easily calculate the optimal parameters. As an example, the application of the code to 238Pu/238U and 148Nd/238U ratios determination in irradiated sample will be discussed.

Pure and iron-doped TiO2 nanoparticles (NPs) for different moles were synthesized by the sol–gel method. The synthesized products were characterized by sophisticated instrumental techniques such as powder X-ray diffraction (XRD), Scanning Electron Microscope (SEM), ultraviolet–visible spectroscopy (UV–Vis) and vibrational sample magnetometer (VSM). XRD pattern confirmed the Rutile structure of Pure TiO2 and Fe doped TiO2 NPs. The doping of Fe into TiO2 proved a great decrease in the size of nanoparticles as compared to undoped TiO2. The various functional groups were identified using FTIR analysis. The surface morphology of pure and Fe doped TiO2 nanoparticles were revealed by scanning electron microscopic analysis. The SEM micrographs revealed flakes like structure of pure and Fe doped TiO2 NPs. UV–Vis Spectrometer showed a sharp absorption edge for pure TiO2 in the ultraviolet region at a wavelength of about 375 nm and the absorption edge for Fe doped TiO2 NPs at a wavelength of about 339 nm. Vibrating Sample Magnetometer (VSM) revealed the ferromagnetic property. The value of magnetic moment showed an increase due to the suitable moles of Fe in TiO2 NPs.

Herein, first time we report the green synthesized zinc sulfide nanoparticles (ZnS NPs) were synthesized by using plant extracts of Tridax procumbens. The structural, morphological and composition analysis of prepared pure and biosynthesized ZnS nanoparticles were scientifically investigated by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) and Energy dispersive analysis of X-ray (EDAX). Optical properties were confirmed with the help of UV–Visible spectroscopy. The obtained results are found that biosynthesized ZnS nanoparticles are highly suitable as bio-catalysts for the degradation of methylene blue dye under visible light degradation. The photocatalytic behaviour of green synthesized ZnS nanoparticles showed outstanding degradation efficiency with better first order kinetic and stability than pure ZnS. This significant enhancement in the degradation behaviour is due to bioactive compounds present in the plant extracts which influence the growth of structural, optical properties in the biosynthesized ZnS nanoparticles.

The high degree of crystallinity of discharging intermediates of Li-S batteries (Li2S2/Li2S) causes a severe capacity attenuation at low temperatures. Herein, a sulfur-rich polymer is fabricated, which enables all the discharging intermediates to exist in an amorphous state without long-range order, promoting the substantial conversion of discharging intermediates and enhancing Li-S batteries' performance at low temperatures greatly. This cathode material exhibits excellent performance both at room and low temperatures. Even under an extremely low temperature (–40 ℃), the discharge capacity can remain 67% of that at room temperature. Besides, in-situ UV/Vis spectroscopy and density functional theory calculations reveal that this organosulfur cathode undergoes a new mechanism during discharge. Li2S6 and Li2S3 are the primary discharging intermediates that are quite different from conventional Li-S batteries. These results provide a new direction for a broader range of applications of Li-S batteries.

This manuscript describes the effect of reaction temperature and time on the structural, morphology and optical properties of cetyltrimethylammonium bromide (CTAB) -assisted ZnO nanostructure grown through hydrothermal process. The samples are characterized by using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), UV–Vis spectroscopy and Fourier transform infra-red spectroscopy. XRD confirmed the hexagonal phase of ZnO. FESEM images estimated the average particle size of nanoparticles in the range of 20–50 nm. The optical band gap estimated by UV–Vis spectra were depends on reaction temperature and time and are in the range of 3.12 – 3.17 eV. A current–voltage (I–V) characteristic proves that conductivity of ZnO nanoparticles also depends upon hydrothermal reaction conditions.

This paper presents synthesis and study of Structural, Optical, and Photocatalytic properties of bismuth ferrite (BFO) and nickel doped bismuth ferrite (BiFe1-xNixO3) nanoparticles. The synthesis of BiFeO3 and BiFe1-xNixO3 (x = 0.02, 0.04) are done by Sol-Gel method. After synthesis the samples of pure and transition metal ion (Ni) doped bismuth ferrite have been studied by using X-ray diffractometer (XRD), X-ray Photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscope and Raman Spectroscopy. Optical properties are studied by using UV–vis spectroscopy using different wavelengths (range 300–800 nm). Photocatalytic properties are also studied by degradation of MB dye using prepared samples as photocatalyst. XRD patterns shows that all the prepared samples are crystalline and crystallinity increased by Ni-doping and shifts in XRD peaks by Ni-doping shows the distortion in the structure of BFO. Raman spectroscopy also indicates the rhombohedral distorted structure of Ni-doped BFO in R3C space group. FESEM micrographs shows that Ni-doped BFO has polyhedral and spherical shape grains and Ni doping cause reduction in grain size. Optical band gap reduced due to Ni-doping is shown by the UV–Vis spectroscopy results and Tauc’s plots. The increase in reduction of MB dye due to Ni-doping shows the enhanced photocatalytic properties of BFO by Ni doping.

Experiments on a modified Orbitrap Exploris instrument have shown that even in a compact instrument it is possible to achieve a resolving power in excess of 2,000,000 when appropriate tolerance and tuning requirements are met. Such levels are achieved for a 4-s detection time. A new Orbitrap design with improved pumping allowed, for the first time, isotopic resolution of intact monoclonal antibodies even when using standard nitrogen supply in the Ion Routing Multipole. Longer transients further improve signal-to-noise ratios, approaching levels needed for single-charge resolution in charge detection mass spectrometry. Further steps for improvement of instrumentation are discussed.

We have analyzed 14 impact melt glass samples, covering the compositional range from highly felsic to mafic/basaltic, as part of our effort to provide mid-infrared spectra (7–14 µm) for MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer), an instrument onboard of the ESA/JAXA BepiColombo mission. Since Mercury was exposed to many impacts in its history, and impact glasses are also common on other bodies, powders of tektites (Irghizite, Libyan Desert Glass, Moldavite, Muong Nong, Thailandite) and impact glasses (from the Dellen, El'gygytgyn, Lonar, Mien, Mistastin, and Popigai impact structures) were analyzed in four size fractions of (0–25, 25–63, 93–125 and 125–250 µm) from 2.5 to 19 µm in bi-directional reflectance. The characteristic Christiansen Feature (CF) is identified between 7.3 µm (Libyan Desert Glass) and 8.2 µm (Dellen). Most samples show mid-infrared spectra typical of highly amorphous material, dominated by a strong Reststrahlen Band (RB) between 8.9 µm (Libyan Desert Glass) and 10.3 µm (Dellen). Even substantial amounts of mineral fragments hardly affect this general band shape. Comparisons of the SiO2 content representing the felsic/mafic composition of the samples with the CF shows felsic/intermediate glass and tektites forming a big group, and comparatively mafic samples a second one. An additional sign of a highly amorphous state is the lack of features at wavelengths longer than ∼15 µm. The tektites and two impact glasses, Irghizite and El'gygytgyn respectively, have much weaker water features than most of the other impact glasses. For the application in remote sensing, spectral features have to be correlated with compositional characteristics of the materials. The dominating RB in the 7–14 µm range correlates well with the SiO2 content, the Christiansen Feature shows similar dependencies. To distinguish between glass and crystalline phases of the same chemical composition, a comparison between CF the SCFM index (SiO2/(SiO2 + CaO + FeO + MgO)) ( Walter and Salisbury [1989 ] J. Geophys. Res., 94, 9203–9213) is useful, if chemical compositional data are also available.

We present an X-ray-optical cross-correlator for the soft (> 150 eV) up to the hard X-ray regime based on a molybdenum-silicon superlattice. The cross-correlation is done by probing intensity and position changes of superlattice Bragg peaks caused by photoexcitation of coherent phonons. This approach is applicable for a wide range of X-ray photon energies as well as for a broad range of excitation wavelengths and requires no external fields or changes of temperature. Moreover, the cross-correlator can be employed on a 10 ps or 100 fs time scale featuring up to 50% total X-ray reflectivity and transient signal changes of more than 20%. (C) 2016 Author(s)., Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe; 1331

We theoretically study the influence of laser polarization in inelastic scattering of electrons by hydrogen atoms in the presence of a circularly polarized laser field in the domain of field strengths below $10^{7}$ V/cm and high projectile energies. A semi-perturbative approach is used in which the interaction of the projectile electrons with the laser field is described by Gordon-Volkov wave functions, while the interaction of the hydrogen atom with the laser field is described by first-order time-dependent perturbation theory. A \textit{closed analytical solution} is derived in laser-assisted inelastic electron-hydrogen scattering for the $1s \to nl$ excitation cross section which is valid for both circular and linear polarizations. For the excitation of the $n=2$ levels simple analytical expressions of differential cross section are derived for laser-assisted inelastic scattering in the perturbative domain, and the differential cross sections by the circularly and linearly polarized laser fields and their ratios for one- and two-photon absorption are calculated as a function of the scattering angle. Detailed numerical results for the angular dependence and the resonance structure of the differential cross sections is discussed for the $1s \to 4l$ excitations of hydrogen in a circularly polarized laser field., Comment: arXiv admin note: text overlap with arXiv:1509.08695

Lead-based relaxor ferroelectrics are key functional materials indispensable for the production of multilayer ceramic capacitors and piezoelectric transducers. Currently there are strong efforts to develop novel environmentally benign lead-free relaxor materials. The structural origins of the relaxor state and the role of composition modifications in these lead-free materials are still not well understood. In the present contribution, the solid-solution (100-x)(Bi1/2Na1/2)TiO3-xBaTiO3 (BNT-xBT), a prototypic lead-free relaxor is studied by the combination of solid-state nuclear magnetic resonance (NMR) spectroscopy, dielectric measurements and ab-initio density functional theory (DFT). For the first time it is shown that the peculiar composition dependence of the EFG distribution width (ΔQISwidth) correlates strongly to the dispersion in dielectric permittivity, a fingerprint of the relaxor state. Significant disorder is found in the local structure of BNT-xBT, as indicated by the analysis of the electric field gradient (EFG) in 23Na 3QMAS NMR spectra. Aided by DFT calculations, this disorder is attributed to a continuous unimodal distribution of octahedral tilting. These results contrast strongly to the previously proposed coexistence of two octahedral tilt systems in BNT-xBT. Based on these results, we propose that considerable octahedral tilt disorder may be a general feature of these oxides and essential for their relaxor properties.

Polymerization enhances the stability of a planar supported lipid bilayer (PSLB) but it also changes its chemical and mechanical properties, attenuates lipid diffusion, and may affect the activity of integral membrane proteins. Mixed bilayers composed of fluid lipids and poly(lipids) may provide an appropriate combination of polymeric stability coupled with the fluidity and elasticity needed to maintain the bioactivity of reconstituted receptors. Previously (

We report an unusually large spacing observed between microparticles after delivery to the surface of a pendent water droplet using a DC nonuniform electrostatic field, primarily via dielectrophoresis. The influence of particle properties was investigated using core particles, which were either coated or surface-modified to alter their wettability and conductivity. Particles that exhibited this spacing were both hydrophobic and possessed some dielectric material exposed to the external field, such as a coating or exposed dielectric core. The origin of this behavior is proposed to be the induced dipole-dipole repulsion between particles, which increases with particle size and decreases when the magnitude of the electric field is reduced. When the particles were no longer subjected to an external field, this large interparticle repulsion ceased and the particles settled to the bottom of the droplet under the force of gravity. We derive a simple model to predict this spacing, with the dipole-dipole repulsion balanced against particle weight. The external electric field was calculated using the existing electric field models. The spacing was found to be dependent on particle density and the induced dipole moment as well as the number of particles present on the droplet interface. As the number of particles increased, a decrease in interparticle spacing was observed.

International audience; Electronic circular dichroism (ECD) and anisotropy spectra carry information on differential absorption of left- and right-circularly polarized light (LCPL and RCPL) by optically active compounds. This makes them powerful tools for the rapid determination of enantiomeric excesses (ee) in asymmetric synthetic and pharmaceutical chemistry, as well as for predicting the ee inducible by ultraviolet (UV) CPL. The ECD response of a chiral molecule is, however, critically dependent on the properties of the surrounding medium. Here, we report on the first ECD/anisotropy spectra of aqueous solutions of the calcium salt dihydrate of glyceric acid. A systematic study of the effect of the salt concentration and pH on the chiroptical response revealed significant changes and the appearance of a new ECD band of opposite sign. Based on the literature, this can be rationalized by the increase in the relative proportion of free glyceric acid/glycerate to Ca2+ complexes with glycerate with decreasing salt concentration or pH. Glyceric acid can be readily produced under astrophysical conditions. The anisotropy spectra of the solution containing prevalently the free form of this dihydroxy carboxylic acid resemble the ones of previously investigated aliphatic chain hydroxycarboxylic acids and proteinogenic amino acids. This indicates possible common handedness of stellar CPL-induced asymmetry in the potential comonomers of primitive proto-peptides.