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It is significant to treat cotton fabrics with flame retardant, which can effectively protect them from damage in the fire. A novel reactive flame retardant coating, ammonium salt of N,N-dimethylene-piperazine-(methylphosphonic acid) (ASNDP), was prepared and employed to enhance the anti-burning effect of pure cotton fabrics. Fourier transform infrared spectroscopy and nuclear magnetic resonance spectrum were used to analyze the chemical composition of the synthesized ASNDP. The combustion behavior and anti-burning performance of coated cotton fabrics were fully investigated with using cone calorimetry test, limited oxygen index (LOI) test and vertical flammability test. The total heat release value of the sample coated with ASNDP (450 g/L) decreased to 3.7 ± 0.1 MJ/m2 and the LOI value of the sample with a weight gain of 17.4 ± 0.3% raised to 29.5 ± 0.1%. The thermal and thermo-oxidative stability of coated cotton fabrics were researched with thermogravimetric analysis. The integral procedural decomposition temperature (IPDT) value of coated cotton fabrics in nitrogen atmosphere increased from 610.1 to 1402.8 °C, which proved that ASNDP inhibited the thermal degradation of fiber unit by promoting the growth of the char layer. Besides, the morphological structure of uncoated and coated samples before and after combustion was characterized by scanning electron microscopy. It can be observed that the fiber skeleton of the coated cotton fabrics was evenly distributed and remained intact after combustion. The conclusion was that ASNDP endowed cotton fabrics with good flame retardancy, and effectively performed the flame-retardant effect in both gas phase and the condensed phase. A novel phosphorus–nitrogen synergistic flame retardant containing multiple reactive groups was successfully synthesized and applied to improve the flame retardancy and thermal stability of pure cotton fabrics.

A novel flame retardant containing phosphorus and nitrogen elements, ammonium salt of N,N-dimethylene p-benzenesulfonic phosphonic acid (ADBSPA), was prepared by one-step continuous chemical method. The chemical structure of the ADBSPA was determined by nuclear magnetic resonance spectrum (NMR) and Fourier transform infrared (FTIR), and ADBSPA was processed onto cotton materials by immersion method. The flame retardancy of coated cotton materials was analyzed by limiting oxygen index (LOI) and Vertical burning test. The LOI value of cotton coated with 350 g/L ADBSPA increased from the original 18.2 ± 0.2% to 31.7 ± 0.2%, and the damaged length of this sample reduced to 6.6 ± 0.1 cm, which proved that ADBSPA enhanced the anti-burning ability of cotton materials. Cone calorimetry was used to evaluate the combustion behavior of cotton materials before and after coating. Compared with original sample, ADBSPA changed the combustion path of cotton materials, and the intuitive performance was that the ADBSPA-cotton-4 reserved 25.1 ± 0.5% of char residue at 250 s, and its peak heat release rate (PHRR) greatly reduced to 17 ± 1 kW/m2. The surface morphology of uncoated and coated cotton materials was characterized by scanning electron microscopy (SEM). It was observed that the coated sample still maintained a complete fiber skeleton after burning. In addition, thermogravimetric (TG) analysis confirmed that the coated cotton materials had good thermo-oxidative and thermal stability. All results pointed out that the phosphorus and nitrogen elements contained in ADBSPA as well as cotton cellulose constituted the three basic conditions of intumescent flame-retardant system. The polyphosphoric acid compounds formed by phosphorus element at high temperature promoted the dehydration of cotton fibers into char layer. The non-flammable gases produced by the nitrogen element in the combustion process covered the surface of fabrics, thereby playing the role of shielding heat and diluting combustible gases. A novel phosphorus-nitrogen flame retardant was prepared by one-step continuous chemical method and applied to improve the thermal stability and anti-flammability of cotton materials.

Fluororubber-modified aluminum (AlF) was investigated by core–shell heat transfer model and compared with traditional aluminum with oxide shell (AlO) in terms of heat transfer effect on the reaction behavior of aluminum. Reaction delay behaviors of both AlF and AlO were calculated with diameter ranging from 200 nm to 3.2 µm at different environment temperature. Calculation results showed that AlF got the upper hand over AlO in terms of reaction delay. In the same heat transfer condition, AlF could participate in the reaction with significantly shorter delay time than AlO, which benefits the energy release of the aluminum. Ceiling shell thickness of AlF was determined according to the basic timescale and temperature profile of the explosive reaction zone. Detonation velocity test of AlF was performed with two kinds of AlO as comparisons. Test proved the AlF exhibited higher reactivity than nanoaluminum. Besides, formulation with AlF showed higher detonation velocity than that with AlO, which on the other side verified the reliability of the heat transfer model. Finally, reaction model of AlF in detonation environment was proposed containing three main procedures.

The hexamethylenediamine-modified graphite oxide/Co-polyamide (GO-HMD/CO-PA) nanocomposites were successfully produced by solution blending method. X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy analyses revealed that GO with a large number of oxygen-containing functional groups was successfully obtained by a modified Hummer’s method. For GO-HMD, the amino and amide bonds were introduced into the GO sheets, making the sheets more incompact, fluffy, and irregular. GO-HMD with a content of less than 1 wt% could be uniformly dispersed in the CO-PA matrix. A series of analysis indicated that the tensile strength, yield strength, and elongation at break of 0.4 wt% GO-HMD/CO-PA increased by 73.4%, 185.9%, and 42.3%, respectively. Thermogravimetric analysis showed that GO-HMD played the role of the heterogeneous nucleation in the matrix and could change the crystal type of the polyamide. The T 50% and Td , max of nanocomposites were 14.3°C and 11.8°C higher than pure polyamide, respectively. The nanofiller GO-HMD contributes to the increase of the thermal diffusivity at low temperature.

Netropsin is one of the first ligands to be discovered that selectively binds to the minor groove of DNA and is actively used as a scaffold for developing potential anticancer and antibiotic agents. The mechanism by which netropsin binds to hairpin DNA remains controversial with two competing mechanisms having been proposed. In one mechanism, netropsin binding induces a hairpin-to-duplex DNA transition. Alternatively, netropsin binds in two thermodynamically different modes at a single duplexed AATT site. Here, results from native mass spectrometry (MS) with nanoscale ion emitters indicate that netropsin can simultaneously and sequentially bind to both hairpin and duplex DNA. Duplex DNA was not detected using conventional MS with larger emitters because nanoscale emitters significantly reduce the extent of salt adduction to ligand-DNA complex ions, including in the presence of relatively high concentrations of nonvolatile salts. Based on native MS and polyacrylamide gel electrophoresis results, the abundances of hairpin and duplex DNA are unaffected by the addition of netropsin. By native MS, the binding affinities for five ligand-DNA and DNA-DNA interactions can be rapidly obtained simultaneously. This research indicates a "simultaneous binding mechanism" for the interactions of netropsin with DNA.

Understanding interactions at the interfaces of carbon with ionic liquids (ILs) is crucially beneficial for the diagnostics and performance improvement of electrochemical devices containing carbon as active materials or conductive additives in electrodes and ILs as solvents or additives in electrolytes. The interfacial interactions of three typical imidazolium-based ILs, 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (AMImTFSI) ILs having ethyl (C2), butyl (C4) and octyl (C8) chains in their cations, with highly oriented pyrolytic graphite (HOPG) were studied in-situ by electrochemical scanning tunneling microscopy (EC-STM). The etching of HOPG surface and the exfoliation of graphite/graphene flakes as well as cation intercalation were observed at the HOPG/C2MImTFSI interface. The etching also takes place in C4MImTFSI at −1.5 V vs Pt but only at step edges with a much slower rate, whereas C8MIm+ cations adsorbs strongly on the HOPG surface under similar conditions with no observable etching or intercalation. The EC-STM observations can be explained by the increase in van der Waals interaction between the cations and the graphite surface with increasing length of alkyl chains.

Aluminum can enhance heat release of energetic composite in theory. However, the commonly used micron aluminum powder has several short comings like incomplete reaction and low reaction rate. Meanwhile, outer oxide shell of nano Al particle is thicker than micro Al, which leads to low active aluminum content and insufficient heat release. On the basis of previous research, reported fluoropolymers modified Al particles were compared and suitable F2311was chosen. Sub-micron scale Al (median particle size around 200 nm) was regarded as optimum coated object in consideration of activity content of aluminum powder changing with particle size. The super fine Al powder was prepared by electrical explosion method, and encapsulated in situ by selected fluorine rubber F2311. The experiments on thermal stability demonstrated F2311 coating thickness should be no less than 3.6 nm. These results were further confirmed by EXPLO5 thermo dynamic calculation. Calculated results showed that reaction characters of F2311 encapsulated Al exceeded conventional nano Al regardless of combustion and explosion. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), laser particle size analyzer and X-ray photoelectron spectroscopy (XPS) were used to characterize coated products’ morphology, particle size distribution and interfacial bonding information. The results showed that the coated samples were generally spherical shape, with median particle size of 217.7 nm and coating thickness of 3.6 nm. The coating shell contained a small amount of alumina and aluminum fluoride besides fluoropolymer. The non-isothermal dynamic equations of Al/F2311 and Al/Al2O3 were deduced by TG/DSC simultaneous thermal analysis. Compared with conventional nano-Al, the apparent activation energy of Al/F2311 decreased by 45 kJ/mol and the first exothermic peak temperature was about 10 °C earlier. Moreover, heat release was nearly twice as conventional nano-Al. TG-DSC-MS coupled measurements certified that active Al was enveloped by ‘fluorine atmosphere’ while F2311 decomposed in range of 200–400 °C. Alumina was replaced with aluminum fluoride inside coating layer during 400–550 °C, which broadened the diffusion path and then accelerated the permeation of oxidizing gas. In addition, the exothermic of Al-F was obviously larger than Al-O. Consequently, the oxidation reaction was activated rapidly, especially in initial exothermic period. Fluoropolymer encapsulated sub-micron sized Al was a latent highly activity energetic fuel and a potential candidate for aluminum powder.

Organophosphates (OPs) are used worldwide as pesticides. However, acute and chronic exposure to OPs can cause serious adverse health effects. The mechanism of delayed OP toxicity is thought to involve off-target inhibition of serine proteases, although the precise molecular details remain unclear owing to the lack of an analytical method for global detection of protein targets of OPs. Here, we report the development of a mass spectrometry method to identify OP-adducted proteins from complex mixtures in a nontargeted manner. Human plasma was incubated with the OP dichlorvos that was 50% isotopically labeled and 50% unlabeled. Proteins and protein adducts were extracted, digested, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to detect "twin ions" of peptides that were covalently modified by a chemical reaction with dichlorvos. The LC-MS/MS data were processed by a blended data analytics software (Xenophile) to detect the amino acid residue sites of proteins that were covalently modified by exposure to OPs. We discovered that OPs can transmethylate the N, S, and O side chains of His, Cys, Glu, Asp, and Lys residues. For model systems, such transmethylation reactions were confirmed by LC-MS, nuclear magnetic resonance (NMR), and rationalized using electronic structure calculations. Methylation of the ubiquitous antioxidant glutathione by dichlorvos can decrease the reducing/oxidizing equilibrium of glutathione in liver extracts, which has been implicated in diseases and pathological conditions associated with delayed OP toxicity.

Microneedles (MNs) are an attractive strategy for the efficient, painless transdermal delivery of drugs with low systemic toxicity. In this work, a novel near-infrared (NIR) light-triggered separable microneedle system was fabricated to supply controlled chemo-thermal therapy to superficial tumors by co-loading a self-developed NIR-II fluorescence fluorophore Flav7 and the antitumor drug doxorubicin (DOX) in phase-change polycaprolactone (PCL) arrowheads on a soluble base. For the MNs we proposed, Flav7 offers MNs with NIR light-triggered heating generation and drug release properties as well as a NIR-II imaging ability for guiding combined chemo-thermal therapy, and the soluble supporting base ensures that the needle arrows are embedded in the skin after insertion and endows the MNs with a separation ability to reduce the contact time of the MNs with the skin. In vitro studies showed that Flav7 + DOX-loaded MNs exhibited adequate insertion abilities, stable thermal properties, and desirable light-activated melting effects and drug release capabilities. In vivo studies showed that the Flav7 + DOX-loaded MNs presented a remarkable NIR-II imaging ability, a good biosafety to the major organs, and a strong tumor-killing ability. It is worth noting that all of the treated breast cancer mice survived for 50 days without tumor recurrences or major organ damage. This study presented a promising MN system loaded with the multipurpose small molecule Flav7 that can be used for high-efficiency light-activated drug release for chemotherapy and high-performance light-controlled thermotherapy of tumors and also for remarkable NIR-II fluorescence imaging to guide chemo-thermal therapy.

Knowledge of the molecular composition and electronic structure of electrified solid-liquid interfaces is key to understanding elemental processes in heterogeneous reactions. Using X-ray absorption spectroscopy in the interface-sensitive electron yield mode (EY-XAS), first-principles electronic structure calculations, and multiscale simulations, we determined the chemical composition of the interfacial region of a polycrystalline platinum electrode in contact with aqueous sulfuric acid solution at potentials between the hydrogen and oxygen evolution reactions. We found that between 0.7 and 1.3 V vs Ag/AgCl the electrical double layer (EDL) region comprises adsorbed sulfate ions with hydrated hydronium ions in the next layer. No evidence was found for bisulfate or Pt-O/Pt-OH species, which have very distinctive spectral signatures. In addition to resolving the long-standing issue of the EDL structure, our work establishes interface- and element-sensitive EY-XAS as a powerful spectroscopic tool for studying condensed phase, buried solid-liquid interfaces relevant to various electrochemical processes and devices.

Dynamic control of the ternary extractive distillation process is complex, due to the relatively high number of operating parameters and interactions between multiple azeotropes. In this research, the control structures of the ternary extractive distillation using dimethyl sulfoxide and a mixed solvent of dimethyl sulfoxide and ethylene glycol, as the entrainer, were explored for separating tetrahydrofuran/ethanol/water. A composition with a ratio of reboiler duty to mole feed flow rate control structure was proposed to obtain good dynamic responses for the ternary extractive distillation process with dimethyl sulfoxide and mixed entrainer. Moreover, control comparisons of the ternary extractive distillation with dimethyl sulfoxide and mixed entrainer demonstrated that the dynamic performances of the extractive distillation with mixed entrainer were better compared with the process using dimethyl sulfoxide. These studies contribute to the development of controllability for ternary extractive distillation ...

To strengthen the anti-tumour efficacy and weaken the side effects, a nano targeted drug delivery system was constructed. The nanostructured lipid carriers (NLCs) were prepared by the melt-emulsification method. Modified with the octaarginine, thiolytic cleavable polyethylene glycol (PEG) and targeting peptide simultaneously on the surface, this multifunctional NLC could not only actively target to tumour tissues, but also control the cell penetration effect of the octaarginine easily by a safe reducing agent l-cysteine (l-Cys). In the present study, the pharmaceutical characteristics, the cytotoxicity and cellular uptake on NCI-H1299 cells in vitro, the biodistribution and targeting effect and anti-tumour ability in vivo were employed to evaluate the formulations. As the results revealed, various NLCs had a mean particle size of about 40 nm and a positive zeta potential of about 10 mV. The optimum density of cleavable PEG was confirmed as 10% and the best concentration of l-cysteine was determined as 20 mM via the qualitative and quantitative cellular uptake study. Based on these outcomes, the multiply decorated NLC manifested a great cell growth inhibition with the increased concentration of paclitaxel (PTX). Moreover, it preferred to accumulate at tumours, but not normal organs in vivo. Compared with Taxol

Low-abundance samples and salt interference are always of great challenges for the practical protein profiling by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Herein, a series of carboxyl-esterified derivatives of α-cyano-4-hydroxycinnamic acid (CHCA) were synthesized and evaluated as matrices for MALDI-MS analysis of protein. Among them, (E)-propyl α-cyano-4-hydroxyl cinnamylate (CHCA-C3) was found to exhibit excellent assay performance for intact proteins by improving the detection sensitivity 10 folds compared with the traditional matrices [i.e., super2,5-dihydroxybenzoic acid (superDHB), sinapic acid (SA), and CHCA]. In addition, CHCA-C3 was shown to have high tolerance to salts, the ion signal of myoglobin was readily detected even in the presence of urea (8 M), NH4HCO3 (2 M), and KH2PO4 (500 mM), meanwhile sample washability was robust. These achievements were mainly attributed to improved ablation ability and increased hydrophobicity or affinity of CHCA-C3 to proteins in comparison with hydrophilic matrixes, leading to more efficient ionization of analyte. Furthermore, direct analysis of proteins from crude egg white demonstrated that CHCA-C3 was a highly efficient matrix for the analysis of low-abundance proteins in complex biological samples. These outstanding performances indicate the tremendous potential use of CHCA-C3 in protein profiling by MALDI-MS. Graphical Abstract ᅟ.

Li2MnSiO4 with a theoretical capacity of 333 mA h g−1 is considered as a potential high capacity cathode material for lithium-ion batteries. However, it suffers from impure phases, low electronic conductivity, and poor cycle performance, which hinder its application in electric vehicles (EVs) and hybrid electric vehicles (HEVs). In this work, a chelating agent-assisted hydrothermal method was proposed to synthesize pure phase Li2MnSiO4 nanorods. Taking advantage of the strong chelating effect of ethylenediamine tetraacetic acid tetrasodium salt (EDTA-4Na), the reaction kinetics was substantially improved by changing the Mn source from Mn(OH)2 precipitate to soluble Mn-containing chelates, which simultaneously controlled the purity and nanoscale architecture of Li2MnSiO4. After coating with amorphous carbon, Li2MnSiO4@C with a 9% carbon coating exhibited a discharge capacity of 275 mA h g−1 in the initial cycle with a current density of 8 mA g−1 (0.05C, 1C = 166 mA g−1), and a better cycle property with a capacity retention of 115 mA h g−1 after 50 cycles was obtained with a higher carbon coating (19%). The good electrochemical properties may be attributed to synergetic effects of the high phase purity and well-dispersed one-dimensional morphology of Li2MnSiO4.

The development of high-energy ammonium perchlorate (NH4ClO4, AP)-based energetic materials is of great significance for promoting their potential applications. In this study, AP-based molecular perovskite energetic materials (H2dabco)[NH4(ClO4)3] were prepared via molecular assembly strategy with the facile one-pot reaction of AP, HClO4 and triethylenediamine (dabco). The as-obtained sample was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR). The thermal decomposition and combustion performance was investigated by thermo-gravimetric/differential scanning calorimeter (TG-DSC), high speed photography and three-dimensional FT-IR. The results showed that combined with the oxidizer perchlorate and fuel dabco at the molecular level, ternary molecular perovskite (H2dabco)[NH4(ClO4)3] possessed a more stable thermal decomposition temperature (385.0 °C) than the monocomponent AP and the heat release is also as high as 3421 J g−1. The thermal decomposition activation energy (181.070 kJ mol−1) of thermal decomposition of (H2dabco)[NH4(ClO4)3] had been expectably reduced from the activation energy (200.259 kJ mol−1) of high-temperature decomposition stage of AP, despite of low-temperature decomposition stage. The synergistic catalysis thermal decomposition mechanism based on the molecular perovskite structures was proposed. And the combustion performance demonstrated molecular perovskite (H2dabco)[NH4(ClO4)3] had a high energy-releasing efficiency. This work provides a proof-of-principle concept for the design and fabrication of high-performance solid propellants based on molecular perovskite (H2dabco)[NH4(ClO4)3].

Copyright © 2018 American Chemical Society. Melimine and its derivatives are synthetic chimeric antimicrobial agents based on protamine and melittin. The binding of solubilized melimine and its derivative, with a cysteine on N-terminus, (cys-melimine) on tethered bilayer lipid membranes (tBLMs) was examined using ac electrical impedance spectroscopy. The addition of melimine and cys-melimine initially increased membrane conduction, which subsequently falls over time. The results were obtained for tBLMs comprising zwitterionic phosphatidylcholine, anionic phosphatidylglycerol, or tBLMs made using purified lipids from Escherichia coli. The effect on conduction is more marked with the cysteine variant than the noncysteine variant. The variation in membrane conduction most probably arises from individual melimines inducing increased ionic permeability, which is then reduced as the melimines aggregate and phase-separate within the membrane. The actions of these antimicrobials are modeled in terms of altering the critical packing parameter (CPP) of the membranes. The variations in the peptide length of cys-melimine were compared with a truncated version of the peptide, cys-mel4. The results suggest that the smaller molecule impacts the membrane by a mechanism that increases the average CPP, reducing membrane conduction. Alternatively, an uncharged alanine-replacement version of melimine still produced an increase in membrane conduction, further supporting the CPP model of geometry-induced toroidal pore alterations. All the data were then compared to their antimicrobial effectiveness for the Gram-positive and Gram-negative strains of bacteria, and their fusogenic properties were examined using dynamic light scattering in 1-oleoyl-2-hydroxy-sn-glycero-3-phosphocholine lipid spheroids. We conclude that a degree of correlation exists between the antimicrobial effectiveness of the peptides studied here and their modulation of membrane conductivity.

Photocatalysis has emerged as an advance and environmental-friendly process for breakdown of organic contaminants in waste water. This work reports facile synthesis and characterization of stable magnetically separable hollow spherical Fe3O4/N-TiO2/Ag and their effectiveness for photocatalysis. Scanning electron microscopy, X-ray diffraction, Energy dispersive X-ray spectroscopy, SQUID magnetometry, UV–Vis absorption spectrum and photoluminescence were performed to investigate the properties of the prepared magnetic photocatalyst. The photocatalytic efficiency of the prepared nanocatalyst was evaluated with decomposition of methyl orange (MO) under visible light and solar light illumination. Fe3O4/N-TiO2/Ag photocatalyst showed large enhancement in the degradation MO compared to undoped TiO2. Moreover, repeated usage of the photocatalyst proved its liability to be collected and reused.

A good understanding of gas-phase fragmentation chemistry of peptides is important for accurate protein identification. Additional product ions obtained by sodiated peptides can provide useful sequence information supplementary to protonated peptides and improve protein identification. In this work, we first demonstrate that the sodiated a3 ions are abundant in the tandem mass spectra of sodium-cationized peptides although observations of a3 ions have rarely been reported in protonated peptides. Quantum chemical calculations combined with tandem mass spectrometry are used to investigate this phenomenon by using a model tetrapeptide GGAG. Our results reveal that the most stable [a3 + Na − H]+ ion is present as a bidentate linear structure in which the sodium cation coordinates to the two backbone carbonyl oxygen atoms. Due to structural inflexibility, further fragmentation of the [a3 + Na − H]+ ion needs to overcome several relatively high energetic barriers to form [b2 + Na − H]+ ion with a diketopiperazine structure. As a result, low abundance of [b2 + Na − H]+ ion is detected at relatively high collision energy. In addition, our computational data also indicate that the common oxazolone pathway to generate [b2 + Na − H]+ from the [a3 + Na − H]+ ion is unlikely. The present work provides a mechanistic insight into how a sodium ion affects the fragmentation behaviors of peptides. Copyright © 2015 John Wiley & Sons, Ltd.

One-dimensional Fe–N-codoped porous carbon materials have shown great potential as sustainable and efficient oxygen reduction reaction (ORR) catalysts. Herein, a highly active ORR 1D Fe–N–C catalyst has been developed by pyrolyzing a complex of polydopamine nanotubes and Fe(NO3)3 at 800 °C. Porous PDA nanotubes as a resource for nitrogen-doped carbon and a coordination platform for Fe3+ can provide well-distributed catalytic sites (Fe–N) after pyrolysis, and generate graphene-like carbon covers with proper thicknesses on Fe/Fe3C nanoparticles that effectively prevent agglomeration. Thanks to the 1D mesoporous morphology and hybrid composition, the rationally designed catalyst exhibits comparable ORR activity to the commercial Pt/C catalyst, and superior durability and methanol tolerance in alkaline media. Polydopamine nanotubes have demonstrated effects in the fabrication of efficient ORR catalysts which can be described as “killing three birds with one stone”. The excellent electrocatalytic performance makes this novel 1D Fe–N–C catalyst a promising non-precious metal catalyst for practical fuel cell application.

Theta nanoelectrospray ionization of protein ions formed from aqueous buffer solutions that are mixed with denaturing solutions containing cyclic alkylcarbonates (e.g., vinyl ethylene carbonate; VEC) results in a significant increase in the extent of ion charging compared to native mass spectrometry. For six proteins, the extent of ion charging can be significantly higher than that obtained using denaturing solutions and alternative native "supercharging" methods. In theta nanoelectrospray supercharging, the extent of charging scales with protein mass in agreement with an analytical scaling relationship for ions with elongated structures. Theta nanoelectrospray supercharging of non-covalent complexes from native solutions results in essentially the complete loss of protein-ligand and protein-protein interactions. Based on circular dichroism spectroscopy, VEC can effectively denature proteins in buffered solutions. These data provide evidence that enrichment of VEC in theta nanoelectrospray ionization generated droplets can denature proteins on the timescale of droplet desolvation and ion formation. This approach can be used to form highly charged protein ions from native solutions containing biological buffers, including some that are considered incompatible with native MS. Forming some protein ions in the highest reported charge states directly from native solutions is no longer a challenge in obtaining primary structural information using tandem mass spectrometry.

An N-terminal deuterohemin-containing hexapeptide (DhHP-6) was designed as a short peptide cytochrome c (Cyt c) mimetic to study the effect of N-terminal charge on peptide fragmentation pathways. This peptide gave different dissociation patterns than normal tryptic peptides. Upon collision-induced dissociation (CID) with an ion trap mass spectrometer, the singly charged peptide ion containing no added proton generated abundant and characteristic bn-44 ions instead of bn-28 (an) ions. Studies by high resolution mass spectrometry (HRMS) and isotope labeling indicate that elimination of 44 Da fragments from b ions occurs via two different pathways: (1) loss of CH3CHO (44.0262) from a Thr side chain; (2) loss of CO2 (43.9898) from the oxazolone structure in the C-terminus. A series of analogues were designed and analyzed. The experimental results combined with Density Functional Theory (DFT) calculations on the proton affinity of the deuteroporphyrin demonstrate that the production of these novel bn-44 ions is related to the N-terminal charge via a charge-remote rather than radical-directed fragmentation pathway.

A new chemical technique for preparing screen-printing paste from commercially-available P-25 powder was proposed to fabricate TiO2 electrodes for dye-sensitized solar cells (DSSCs). The TiO2 powder and acetic acid were dispersed in ethanol, following that the reactants solutions kept at 80 °C for 12 h, then dried in oven for 6 h. This process made the TiO2 particle positively charged and highly dispersed in water. Additionally flocculating reaction using hydrochloric acid was done to change the dispersed TiO2 colloid into viscous paste, which omitted the process of adding polymers as thickener, and kept the purity and porosity of electrodes. The mesoporous transparent TiO2 films about 14 μm thickness without cracking and peeling-off were fabricated on conducting glass substrates. A high conversion efficiency of 8.07% was obtained under 100 mW cm−2 AM 1.5 illumination.

In this study, we have fabricated by electrodeposition FePt ordered nanowires through the use of ordered nanopore anodized aluminum oxide templates. The scanning electron microscopy studies show that FePt nanowires about 50 nm in diameter are uniformly embedded into anodic alumina-nanoholes. Nevertheless, as-deposited and annealed in vacuum films exhibit a magnetization much lower than expected. Changes of the annealing atmosphere from vacuum to hydrogen bring about the improvement of the L1 0 FePt properties because of the reduction of Fe oxide in the as-deposited films. The coercivity of 1.8 KOe is achieved by post-annealing at less than 300 °C in hydrogen.

The cropping patterns as drip irrigation under mulch were assumed in the experiment with peanut variety "Fu Hua 17" to study the effects of different topdressing on photosynthetic characteristics and yield for peanuts. Five different treatments were carried out to determine the photosynthetic characteristics, and a comprehensive evaluation was made in combination with the yields. The results showed that the diurnal changes for T1 (PK+Ca) and T2 (N+Ca) in the photosynthetic rate were lower than those in T3 (N+PK) and T4 (N+PK+Ca), a fact illustrating that N, P and K elements have a direct impact on peanut photosynthetic rate, chlorophyll SPAD value of the three treatments continued to decline at the beginning of flowering, which means that leaf chlorosis and fertilizer shortage appeared earlier for peanuts in the middle and late period. The sequence of yield was: T4 (N+PK+Ca) > T3 (N+PK) > T2 (N+Ca) > T1 (PK+Ca) > T5 (CK without topdressing). T4 yield was slightly higher than T3, a result showing with sufficient NPK, increasing Ca fertilizer could increase yield and efficiency. The studied results could offer theoretical basis for revealing the yield increasing mechanism of integrated management of water and fertilizer under mulched drip irrigation. Keywords-peanut; drip irrigation; photosynthetic characteristics; yield The peanuts production mainly depends on photosynthesis, and peanuts photosynthesis capacity is not only related to their own intrinsic factors, but also related to such external factors as illumination intensity, CO2 concentration, temperature, humidity, fertilizer and water[1-3]. According to some researches, nitrogen, as the necessary mineral element of chlorophyll biosynthesis, will have a direct impact on the enzyme content; phosphorus and potassium will stimulate the transfer and transport of photosynthates, thus affecting photosynthesis in an indirect way. Planting mode could improve population structure and soil micro-environment, and shall directly or indirectly affect photosynthesis, and therefore exert impacts on the production. Drip irrigation origins from Israel in the 1960s. In the 1990s, Xinjiang succeeded in the drip irrigation experiment for field cotton[7-9]. In 2011, drip irrigation technology was adopted for peanuts planting in sandy semiarid region in northwest Liaoning province, China. At present, many researchers have already completed a series of studies on drip irrigation planting technology and translocation of water and fertilizer, but they are mostly on cottons and fruit trees. There are few researches on translocation rule and yield-increasing mechanism for peanuts with fertilization under mulched drip irrigation in the local area, especially without intensive studies on photosynthetic physiological characteristics. This article, whose focus is on peanut cultivation in sandy semiarid region under mulched drip irrigation, will prove to be thorough studies about impacts on peanut photosynthesis characteristics and chlorophyll content with the different topdressing under fertilization, while in combination of harvest fluctuation features for further analytic demonstration, all of which shall serve as theoretical reference for more detailed research on drip irrigation for peanut growth and physiological changes impact, most important to the further discovery of peanut yield increase under drip irrigation with fertilization[10-12]. International Conference on Mechatronics, Electronic, Industrial and Control Engineering (MEIC 2015) © 2015. The authors Published by Atlantis Press 977 I. MATERIALS AND METHODS A. General situation of test area The experiment was conducted at Zhanggutai test station of Liaoning Academy of Agricultural Sciences, with the conditions as north latitude 42°42′, east longitude 122°32′, altitude 213.1 m, loam soil for farming, organic matter content of 27.4g/kg, available nitrogen 143 mg/kg, phosphorus 66.0 mg/kg, potassium 108 mg/kg, pH value of 5.6. In this area, frost-free period is 150~155 days, with accumulated temperature (≥ 10°C) as 3468°C, annual average temperature as 6.82°C. The annual average rainfall is 500~520mm, mostly focused in July and August, and the annual average evaporation is 1600~1800mm. Dryness is about 4.0, as that in a semi arid region, where spring drought, summer drought and autumn hanging occurs, or spring drought, summer drought and autumn hanging occurs alternately. B. Research design and methods Cropping patterns as drip irrigation under mulch was adopted for such an experiment, with the detailed description as furrow top width of 65cm, ridge furrow bottom width of 95-100cm, 10cm~12cm high, two rows for furrow planting with row spacing of 35cm, where in the dripping belts were paved, row spacing of 8~10cm for precise sowing of a single seed[13-14] , and the planting density was 14,000 plants per 667m2. The drip fertilization period is the flowering stage (early July) and pod swelling stage (early August) respectively, with irrigation amount as 10m3/667m2 times, drip irrigation fertilizer: urea (N), phosphorus and potassium (PK), Calcium nitrate (Ga) for 5 treatments as specified, of which T5 is as the control without topdressing (see Table 1). Each cell is 25 m long and 4 m wide, three times repeated.. Coated mechanical seeding was conducted in mid May, 2014, with fertilization as organic fertilizer 3000kg/667m2, peanut release fertilizer 50kg/667m2, peanut-specific fertilizer 10kg/667m2, multi-micronutrient fertilizer 1kg / 667m2 before sowing. Tested variety is Fu Hua17. TABLE 1 DIFFERENT FERTILIZER APPLICATION RATES FOR PEANUTS UNDER MULCHED DRIP IRRIGATION The experimental plot number Treatment Fertilizer amount(kg/667m2.times)

Multidrug resistance (MDR) is a major challenge for cancer therapy. Herein, we report a simple yet effective system, cell-penetrating peptide (CPP)-assisted poly(lactic-co-glycolic acid nanoparticles (PLGA NPs), for improving doxorubicin (DOX) delivery and overcoming MDR cancer. We selected the naturally derived CPP low-molecular-weight protamine (LMWP) to modify PLGA NP for enhanced drug delivery. We demonstrated that multiple mechanisms ("synergistic multipronged delivery") were responsible for the anti-MDR effects of LMWP/PLGA NP. This delivery system could boost intracellular and intranuclear delivery, thereby circumventing drug efflux. Use of a P-glycoprotein inhibitor did not further increase the efficiency of intracellular delivery of LMWP/PLGA/DOX NP, suggesting that delivery of LMWP-based NP was not affected by transporter-mediated drug efflux. Importantly, enhanced uptake and penetration within the tumor was found in mice given LMWP-based NP. LMWP/PLGA NP effectively arrested tumor growth in mice harboring drug-resistant breast tumors, thereby improving treatment outcomes without detectable toxicities. These data suggest that our system could provide effective yet safe anti-MDR cancer therapy based on a synergistic, multipronged drug-delivery strategy.

Benefiting from extremely high conductivity, graphene sheets (GS) with very low defect density are preferable to reduced graphene oxide sheets for constructing the free-standing hybrid electrodes of flexible electrochemical energy storage devices. However, due to the hydrophobic nature and deficiency of nucleation sites, how to uniformly and intimately anchor electrochemically active materials onto less defective GS is a challenge. Herein, a free-standing and mechanically flexible hybrid film with two-layer structure, mesoporous TiO2 anchored less defective GS hybrid (mTiO2-GS) upper-layer and graphene under-layer, denoted as mTiO2-GS/G, is fabricated. The hydrolysis of a Ti glycolate aqueous sol solution were applied to form mTiO2. The decoration of less defective GS with sodium lignosulfonate (SLS) surfactant is crucial for anchoring TiO2 nanoparticles (NPs). The aromatic rings of SLS favor a non-destructive functionalization of GS through the π-π stacking interaction. The sulfonic acid groups and hydroxyl groups of SLS, respectively, greatly improve the dispersity of GS in water and trigger the nucleation of TiO2 through the oxolation in the hydrolysis of Ti glycolate sol solution. The following characteristics of free-standing mTiO2-GS/G electrode benefit the fast charging/discharging capabilities: highly conductive graphene framework, ultra-small NPs (~5.0 nm) in mTiO2 anchored, high specific surface area (202.5 m2 g−1), abundant mesopores (0.32 cm3 g−1), intimate interfacial interaction between mTiO2 and GS, robust contact between the mTiO2-GS upper-layer and an under-layer of bare graphene as the current collector. In coin half-cells, the mTiO2-GS/G electrode delivers a capacity of 130 mA h g−1 at 50 C, and 71 mA h g−1 at 100 C, and it also exhibits excellent cycle stability up to 10 000 cycles under 10 C, with a degradation rate of 0.0033% per cycle. When packed in flexible cells, the mTiO2-GS/G electrode maintains fast charging/discharging capabilities regardless of being flat or bent. Furthermore, because of the high durability of mTiO2-GS/G electrode, repeated deformations do not cause extra capacity degradation.

We investigated the x-ray absorption spectroscopy (XAS) fingerprint of EMImTFSI ionic liquid (IL) and its fragmentation products created by x-ray irradiation. To accomplish this, we used an open geometry where an IL droplet is directly exposed in the vacuum chamber, and an enclosed geometry where the IL is confined in a cell covered by an x-ray transparent membrane. In the open geometry, the XAS signature was stable and consistent with experimental and theoretical spectra reported in the literature. In contrast, when the IL is enclosed, its XAS evolved continuously under x-ray illumination due to accumulation of volatile fragmentation products inside the closed cell, while they evaporate in the open geometry. The changes in the XAS from the core levels of relevant elements (C, N, S, F) together with density functional theory (DFT) calculations, allowed us to identify the chemical nature of the fragment products and the chemical bonds most vulnerable to rupture under soft x-ray irradiation.