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The increase of CO2 concentration in the atmosphere has brought serious greenhouse effects and environmental problems, so it is urgent to solve the problem of excessive CO2 concentration. The carbon capture, utilization, and storage technology refer to the use of CO2 as a C1 resource to generate new economic benefits in a new production process. In this work, the influence of adding different proportions of N2 and Ar to the CO2 gas on the discharge characteristics and reaction performance was investigated with a newly designed dielectric barrier discharge (DBD) micro-plasma segmented electrode reactor and optical emission spectroscopy. The results indicated that the discharge current value increased when the added N2 content was less than 50%, and decreased when the N2 content exceeded 50% under the condition of constant input power. The number and the current value of mixed gas micro-discharges showed a decreasing trend with the increase of Ar content. In the discharge system, the dielectric capacitance (Cd) and the gas gap capacitance (Cg) showed opposite trends with the increase of N2 and Ar content. The dielectric capacitance decreased and the gas gap capacitance increased as the N2 content increased, while the trend was just the opposite as the Ar content increased. In addition, adding a small amount of N2 and Ar was conducive to the conversion of CO2, but when the N2 and Ar content exceeded 50%, the amount of CO2 converted will be reduced.

The performance of the ZSM-5 zeolite catalysts modified by Au only, Mn only and both Au and Mn for catalytic cracking of light diesel were evaluated in this study. The gold-manganese modified catalyst showed better catalytic activity than the manganese-only or gold-only modified catalysts, as indicated by the improved propylene selectivity and micro-reaction activity index. It was found that small and uniform manganese nanoparticles with a mean diameter of 20 nm were homogeneously dispersed on ZSM-5 while uneven larger Au (> 100 nm) particles were deposited separately on the ZSM-5 surface. Significantly higher values of surface acidity were obtained for the Au–Mn/ZSM-5 catalysts compared to those for the Mn/ZSM-5 catalysts and ZSM-5 itself. With increasing manganese content, the acid strength and total acid content first increased and then decreased. The AuMn-modified ZSM-5 catalysts largely retain the crystal structure of ZSM-5 after a hydrothermal treatment, showing that the hydrothermal stability of the catalysts was enhanced and the loss of their surface acidity was reinforced by the double AuMn modification. Among all of the catalysts, 1%Au-3%Mn/ZSM-5 shows the best performance, since it maintains the intact structure and even narrower pore size distribution of the parent ZSM-5 zeolite as well as moderate acidity.

Various ZrO2 with pure tetragonal, monoclinic, and mixed phases were used as carriers of gold nanoparticles for an exploration to production of propylene oxide (PO) in co-presence of propylene with H2 and O2. Catalysts with similar gold dispersion (2–5 nm gold particles) were prepared by a deposition–precipitation method. 100% selectivity to PO was obtained for the first time over non-titanium-supported Au catalysts on both tetragonal and monoclinic ZrO2 supports, which needs a good match of nanogold and active sites (quite possible hydroxyls connected with Zr4+). However, Au/tetragonal ZrO2 benefits PO formation that could be accelerated by hydroxyl groups while Au/monoclinic ZrO2 generates more acrolein and suppresses CO2 formation. The active sites for the production of PO are speculated to be Au and Zr-O rectangular pyramids in ZrO2, similar to that on TiO2 and acrolein appears on the Au near oxygen vacancies.

A highly active [N^N−] iridium complex [Cp*Ir(pba)Cl] (3, Cp* = pentamethylcyclopentadiene, pba = 4-(picolinamido)benzoic acid) has been obtained with an anionic ligand, which exhibited the most robust performance for cofactor NADH regeneration in physiological conditions with HCOONa as the hydrogen source. The structure of complex 3 was revealed by X-ray single-crystal structure analysis. The turnover frequency (TOF) of complex 3 in the regeneration of NADH is 7825 h−1, which is about 22.7 times and 178 times higher than that of the C−^N type complex 2 (345 h−1) and N^N complex 1 (44 h−1) at 37 °C, respectively. The high activity of complex 3 seems to be critically affected by the negatively charged N− of the amide chelating ligand, which could promote the reaction rate of Ir–Cl conversion to Ir–H2O. Furthermore, complex 3 shows good biocompatibility for various biomolecules except SH-compounds (such as reduced glutathione (GSH)). When combined with NADH-dependent enzymes (KRED-101), the complex 3-based NADH-regeneration catalytic system shows stable chemoenzymatical coordinate catalytic activity for reducing acetophenone to the corresponding alcohol with high enantioselectivity.

The degradation of toxic chemicals, antibiotics and other residues in organic wastewater has attracted much attention. Among various degradation technologies, hydrodynamic cavitation (HC) reactors have the advantage of being simple to operate. Through the combination of HC and other oxidants, the removal efficiency and energy efficiency of organic matter can be greatly improved, and the consumption of chemicals and the processing costs can be reduced. In this work, HC technology combined with oxidants was used to degrade pefloxacin (PEF), and the effect of different operating conditions on PEF degradation was investigated. The results indicated that the removal efficiency of PEF treated with HC alone was 84.9% under the optimal HC conditions of pH 3.3 and 120 min, which is much higher than that (35.5%) of pH 5.3. When co-treating the PEF solution with HC and H

Gold nanocatalysts have been reported to be active in the selective hydrogenation of acetylene. In this paper, a series of Au/Ce1−xZrxO2 (x = 0.03 to 0.5) supported catalysts with different ratios of Ce to Zr were prepared and their catalytic performance for selective hydrogenation of acetylene was investigated. The structure and surface defects of the catalyst can be changed by altering the amount of Zr incorporation. Compared to both Au/CeO2 and Au/ZrO2, the synthesized Au/Ce1−xZrxO2 showed the higher catalytic activity with keeping almost 100% ethylene selectivity at 300 °C. The TEM observation indicated that the incorporation of Zr led to the formation of hollow spherical solid solutions. The specific surface area also has a certain influence on the catalytic activity. Considering the catalytic activity of Au/Ce1−xZrxO2 and their characterizations by XPS and Raman, the concentration of Ce4+ and the oxygen vacancy of the Ce1−xZrxO2 support play an important role in the selective hydrogenation of acetylene.

In this paper, the decomposition of pure CO2 into CO and O2 were carried out in a segmented electrode DBD micro-plasma reactor at ambient pressure. With the assistance of gas chromatography, the influence of key factors like electrode interval and barrier thickness on the DBD filamentary behavior and CO2 decomposition process were investigated systematically. Meanwhile, the detailed electrical characterization during discharge process was also performed. The results indicated that a relatively higher CO2 conversion and energy efficiency could be obtained at the propitious condition of longer interval between adjacent electrodes and smaller barrier thickness, and the highest CO2 conversion and corresponding energy efficiency are 16.9% and 3.6%, respectively, at the condition of an applied voltage of 18 kV and 1.0 mm barrier thickness. Longer electrode interval can result in an increase in plasma density as well as enhance fringe effect. While the smaller barrier thickness, the smaller corresponding gas breakdown voltage, which meant that more electrical power was used for gas excitation. Accordingly, more energetic electrons were generated and more collisions between the electrons and CO2 molecules occurred. These were considered to be main reasons for enhanced CO2 decomposition process.

In order to achieve better chemical absorption of NOx and SOX, oxidation of NO in the process of simultaneous desulfurization and denitrification of the flue gas based on ozone oxidation was studied. The main investigations focused on factors affecting NO oxidation including the molar ratio of O3/NO (MR) (0.6–1.2), the oxidation temperature (65−150 °C), the initial NO concentration (100−500 mg/Nm3), the presence of SO2 (1000−5000 mg/Nm3), the content of water vapor (5–15 %) and the residence time (0.07–1.8 s). The results indicated that MR had a substantial effect on NO conversion and the products of NO oxidation by O3 varied with the change of MR. When MR ≤ 1, the NO conversion increased from less than 60 % to more than 95 % with the increase of MR, and the oxidation product was mainly NO2. When MR(O3/NO) > 1, the NO conversion rate (about 97 %) basically remained unchanged, and the oxidation products under these circumstances were mainly NO2 and N2O5. When the oxidation temperature rose from 65 to 150℃, the conversion of NO was almost unchanged. Besides, the NO initial concentration, the presence of SO2, the water vapor content and the length of the flue gas outlet pipe had negligible impact on the NO conversion within the range selected for the study.

Modulating the active sites for controllable tuning of the catalytic activity has been the goal of much research, however, this remains challenging. The O vacancy is well known as an active site in reducible oxides. To modify the activity of O vacancies in praseodymia, we synthesized a series of praseodymia-titania mixed oxides. Varying the Pr : Ti mole ratio (2 : 1, 1 : 2, 1 : 1, 1 : 4) allows us to control the electronic interactions between Au, Pr and Ti cations and the local chemical environment of the O vacancies. These effects have been studied study by X-ray photoelectron spectroscopy (XPS), CO diffuse reflectance Fourier transform infrared spectroscopy (CO-DRIFTS) and temperature-programmed reduction (CO-TPR, H

A series of highly porous metal organic framework ZIF-8 supported Au nanoparticles materials with different Au particle size were prepared through one-pot method at room temperature. The obtained heterogeneous catalysts were comprehensively characterized by powder X-ray diffraction, N2 adsorption, FTIR spectroscopy, scanning electron microscope and transmission electron microscopy. The intact crystallinity of ZIF-8 was found before and after the Au loading, and Au nanoparticles with different particle size were found homogeneously dispersed in ZIF-8. The obtained Au catalysts exhibited high activity and stability for hydrogenation of 4-nitrophenol, with excellent selectivity to aminophenol. It had been shown that the Au particle size played important roles in the activity. The as-prepared catalysts exhibit relatively excellent activity and selectivity in the reduction of p-nitrobenzonitrile to p-aminobenzonitrile, which is benefit from the high selectivity of Au particles.

Supported gold nanoparticles are highly selective catalysts for hydrogenation of acetylene, but low activity and heavy coke effect have been major concern for the Au-based catalysts. Based on a modified impregnation-calcination strategy, a series of MgOx-Al2O3 composite oxides with different crystal structures from mixed phase to pure spinel was prepared. Due to its crystal defect and synergetic effect, Au nanoparticles on MgOx-Al2O3 components treated at 550 °C (abbreviated as Au/3%MgOx-Al2O3-550) with well controlled smaller particle size gave an enhanced activity for the selective acetylene hydrogenation. The conversion rate was nearly twice as high as that of all other samples at 250 °C. The H2-TPR and XPS results indicate the partially positive charged Au species (Auδ+) played a crucial role in facilitating the adsorption of the C C group. Both the temperature programmed oxidation and Raman scattering also indicated that the Au/3%MgOx-Al2O3-550 showed better decoking effect than Au/Al2O3. This report opens up promising possibilities on engineering the crystal phase of support for the highly efficient heterogeneous gold catalysts.

A group of luminescent dinuclear Ir(III) complexes were synthesized to study the application possibility as luminescent G-quadruplex (G4) sensors. According to the results, the dinuclear Ir(III) complexes 1–5 were assessed as selective G4 sensors. Among them, complex 5 not only demonstrates the highest specificity towards G4, but also shows linearly enhanced luminescent intensity with the increase of split G4 concentration. Complex 5 was thus utilized to establish a label-free split G4-based detection platform for luminescent detection of transcription factor (TF). This luminescent assay is simple and sensitive with the detection limit of 0.027 nM for NF-κB p50 in aqueous solution. The split G4-based TF sensing platform also worked well in diluted human serum, demonstrating high application potential for biological sample analysis.

In order to clarify the nature of cooperation effect of gold–copper in CO oxidation without disturb of substrate materials, in this work we prepared nano-sized copper and cuprous oxide with different morphologies followed by the deposition of gold nanoparticles. The reaction of CO oxidation under both hydrogen-rich and oxygen-rich streams was investigated over as-prepared CuO/Cu2O materials and the corresponding supported gold catalysts. The characterizations reveal that in the unreduced Au/Cu2O samples, Au+–Cu2+ assembles are dominant on the surface of Cu2O substrate due to the spontaneous oxidation–reduction reaction of Au3+ and Cu+, while both of Au3+-Cu2+ and Au+-Cu2+ entireties are existed in the unreduced Au/CuO sample and the former is dominant. A comprehensive analysis of the catalytic results over these samples for CO oxidation in both oxygen-rich and hydrogen-rich streams demonstrates that the CuO species (not Cu2O) play a more critical role for the oxidation of CO and the improved catalytic activity of the Au/CuO catalyst can be attributed to the strong interactions of CuO support with nanogold particles.

Catalytic conversion of n-octane and light diesel oil was carried out over ZSM-5 comodified with gold and lanthanum by modified deposition-precipitation and wet impregnation methods. A series of ZS...

In this paper, core-shell SiO2/polypyrrole (SiO2/PPy) composites were prepared via in situ chemical oxidation of pyrrole monomer on surface of the modified SiO2 by using FeCl3 as the oxidant. Au nanoparticles (NPs) were loaded on SiO2/PPy composites by means of the redox reaction between PPy and gold ions. Several analytical tools, such as TEM, FT-IR, XRD and EDX, were employed to characterize the morphology and structure of the as-prepared SiO2/PPy/Au composites. Their catalytic performances in reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) with NaBH4 as the reducing agent were studied. Results showed that the conversion of 4-NP was increased with an decrease of Au loading. The reduction of trace AuCl4− ions in core-shell composites to small Au NPs by NaBH4 in the beginning of the reaction favored the enhancement of catalytic activity.

Supported gold catalysts are highly efficient for selective hydrogenation of acetylene. It has been shown that reducible materials such as ceria may influence the catalytic performance due to its unique charge shift between reduced and oxidized state. However, its role in catalytic performance remains fiercely debated. In this paper, differently morphological CeO2 supported Au catalysts were prepared with pretreatment under air and H2 atmospheres respectively, and evaluated for selective hydrogenation of acetylene. No matter with rod (abbreviated as R) or polyhedral (abbreviated as P) shape, the catalysts of Au/CeO2 reduced in air exhibits better catalytic performance than that in H2 atmosphere. The Au/CeO2 (R)-air catalyst shows the best performance. The C2H2 conversion is about three times of that over the catalyst of Au/CeO2 (R)-H2 at 300 °C. The Raman result and XPS analysis clearly showed a dependence of catalytic activity on the oxygen vacancy concentration of catalysts, revealing the correlation between its defect features and pretreatment atmosphere. Our report not only deepens the knowledge of catalytic performance affected by defect features of catalyst but also provides a possibility for the efficient heterogeneous gold/ceria catalysts by controlling the pretreatment atmosphere.

H1N1 swine influenza virus (SIV) has posed a potential threat to public health. Genetic evolution and amino acid substitutions of whole genome sequence of influenza virus have been shown to be associated with the virulence and pathogenicity of the virus. We made a statistical analysis of the prevalence of swine influenza virus in China and found that Eurasian avian-like H1N1 (EA-H1N1) SIVs were the main prevalent SIVs in China. We further analyzed the genotypes of EA-H1N1 SIVs, and the results showed that these viruses were divided into 11 genotypes, and there is an increasing number of reassorted EA-H1N1 SIVs in recent years, especially for those viruses whose viral genes PB2, PB1, PA and NP derived from pandemic H1N1/2009. Besides, we isolated a novel EA-H1N1 SIV (A/swine/Hubei/221/2006 (H1N1)). We find that this isolated virus is highly homologous to a previous human isolated EA-H1N1 virus A/Hunan/42443/2015 (H1N1). Taken together, this study analyzes the prevalence and genetic evolution of EA-H1N1 SIVs in China, which provides a theoretical basis for the prevention and control of swine flu.

In this study, the tribological performances of steel/steel and steel/TiN coating systems are investigated under the condition of boundary lubrication by a PAO base oil containing various concentrations of MoDTC. Additionally, the effects of the MoDTC concentration and the contact pressure on the tribochemical decomposition reaction of MoDTC are discussed. In an experiment, a significantly low friction coefficient and wear rate were observed for the TiN coating as compared with the reference steel in the presence of MoDTC in the PAO6 base oil. Moreover, the tribocatalytic effect of TiN coating on the complete decomposition of MoDTC to form a tribofilm containing MoS2 is discussed.

To improve the G-quadruplex specificity of Ir(III) complexes, a novel dinuclear Ir(III) complex (Din Ir(III)-1) was designed and synthesized through connecting two mononuclear Ir(III) complexes via a diphenyl bridge. Din Ir(III)-1 presents 3.4-4.1-fold enhancements for G-quadruplex relative to ssDNA and 4.3-5.3-fold enhancements relative to dsDNA in luminescence intensity, respectively, demonstrating an excellent G-quadruplex selectivity. Ascribed to its superior specificity to G-quadruplex, Din Ir(III)-1 was employed to construct a highly sensitive luminescent pesticides' detection platform. The detection is based on acetylcholinesterase (AChE)-catalyzed hydrolysis product-induced DNA conformational transformation and subsequent terminal deoxynucleotidyl transferase (TdT) directed G-quadruplex formation. The assay exhibited a linear response between the emission intensity of Din Ir(III)-1 and the pesticide concentration in the range of 0.5-25 μg/L ( R2 = 0.994), and the limit of detection for the pesticide was as low as 0.37 μg/L when using aldicarb as the model pesticide. Moreover, this strategy demonstrates good applicability for the pesticide detection in real samples. It is also versatile for the detection of other organophosphate or carbamate pesticides, which have the inhibition ability toward AChE. Therefore, the proposed approach is scalable for practical application in food safety and environmental monitoring fields and will provide promising solutions for the assay of pesticide residues.

The YVO4 nanospindles with well-crystallization were synthesized through a facile and rapid chemical conversion route. The synthesis started with the precipitation of sheet-like yttrium precursor Y2(OH)5NO3∙nH2O at room temperature. With the addition of vanadate, YVO4 nanospindles were formed at the expense of the precursor in less than 10 min at 120 °C. The obtained particle shape and size are insensitive to experimental parameters, such as pH value and reaction temperature. The synthesis route is environment-friendly which involves no template or surfactant, but only relates to facile aqueous conditions at low temperature. We also investigated the luminescence properties of YVO4:Eu3+ and gold functioned Au/YVO4:Eu3+ products. Under UV excitation, both samples show strong red luminescence due to the radiative transitions of Eu3+, while the excitation spectra vary significantly. The interactions between Au nanoparticles (NPs) and the YVO4:Eu3+ NPs were also investiged.

Lateral vibrations of suspension and compensating ropes in a high-rise elevator system are induced by the building motions. When the frequency of the building coincides with the fundamental natural frequency of the ropes, large resonance whirling motions of the ropes result. This phenomenon leads to impacts of the ropes the elevator walls, making the building and elevator system unsafe. The impact loads affect the performance of the elevator installation resulting in interruptions of service and damage to the components of the system. Furthermore, the car, counterweight and compensating sheave suffer from vertical vibrations due to the coupling with the lateral vibrations of the ropes. This paper presents a comprehensive mathematical model of a high-rise elevator system taking into account a scenario when the car is parked at the landing level corresponding to the resonance length of the ropes. The model is implemented in a high performance computational environment and the dynamic response of the system when the building is subject to a low frequency sway, is determined through numerical simulation. The results predict a range of nonlinear dynamic interactions between the components of the elevator system that play a significant role in the operation of the entire installation.

As one of the advanced oxidation processes, the cavitation-based process has become a promising technology for treating industrial effluents due to the advantages of cost-effectiveness in operation, higher energy efficiencies, and large-scale operation. In hydrodynamic cavitation (HC), cavities are generated as a result of local pressure drops caused by various constrictors or by mechanical rotation of the vortex diode and other rotating-type devices. The study on the influence of various geometric parameters of different kinds of HC reactors and the operation conditions is popular among researchers. In the present work, we systematically introduced the formation of HC and the mechanism of degradation of pollutants by HC. Further, for various cavitating devices, the influence of various geometrical and operating parameters affecting the cavitation conditions was discussed in detail. Overviews of earlier work based on the different types of HC reactors including venturi, orifice plate, rotating-type HC devices, and vortex diode were elaborated. Moreover, a detailed summary of HC-based hybrid technologies employed in recent work was presented to better show the synergetic index of different processes. Some recommendations for future work have been proposed.

To establish a positive cloning system with a zero background for high-throughput DNA cloning purpose. The cloning vector, pRI857, and the genomic-library construction vector, pRI857-BAC, were constructed based on the mechanism of expression of the thermo-sensitive cI857 repressor gene that can stringently repress the PR promoter and kanamycin resistance gene (PR-kan R ) at 30 °C, but have no effect on PR-kan R gene at 37 °C or at higher temperatures. When the pRI857 vectors were transformed into E. coli with or without a target foreign DNA fragment inserted at the BfrBI site of the cI857 gene, only colonies with the foreign DNA fragment survive. We extended this method to construct a pRI857-BAC vector for genomic library cloning which displays an efficiency of ~107 cfu per µg of genomic DNA, with no empty vectors detected. Cloning by indirect activation of resistance marker gene represents a novel DNA-capturing system, which can be widely applied for high-throughput DNA cloning.

Herein, polystyrene/polyaniline/Au (PS/PANI/Au) composites were prepared by a novel method using self-made Au(en)2Cl3 as the Au source and were used as the catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). Before the preparation of PS/PANI/Au, PS microparticles were sulfonated by the copolymerization between styrene and sodium 4-styrenesulfonate (SSS). Then self-made Au(en)2Cl3 was added and Au(en)23+ species were adsorbed on the surface of sulfonated PS particles due to the electrostatic attraction. The Au(en)23+ was then reduced to Au nanoparticles in situ by aniline monomer. After the polymerization of the residual aniline monomer by ammonium persulfate (APS), the PS/PANI/Au composite catalysts were obtained. The morphology and structure of the as-prepared PS/PANI/Au composites were characterized by TEM, FT-IR, XPS and EDX. Their catalytic performance for the reduction of 4-NP by NaBH4 was evaluated by means of UV–vis spectroscopy. The as-prepared PS/PANI/Au composites are very active for the reduction of 4-NP by virtue of the interaction between Au nanoparticles and PANI shell. The catalytic reaction obeys the pseudo-first-order reaction equations and the reaction rate constants are also calculated in this paper.

A novel Au/Fe–V–Ox/Al2O3 catalyst displayed remarkable activity and good stability for CO oxidation in the simulated atmosphere of a CO2 laser with high CO2 levels up to 60 vol% and stoichiometric or even lower O2/CO ratio. The improved surface labile lattice oxygen on the FeOx and VOx modified Al2O3 plays a crucial role in its outstanding performance for the CO oxidation reaction in an oxygen-poor atmosphere.

The catalytic cracking of light diesel oil (235-337℃) over gold-modified ZSM-5 was investigated in a small confined fluidized bed at 460℃ and ambient pressure. Different Au/ZSM-5 catalysts were prepared by a modified deposition-precipitation method by changing the preparation procedure and the amount of gold loading and were characterized by X-ray diffraction, N 2 adsorption-desorption, temperature-programmed desorption of NH 3 , transmission electron microscopy and inductively coupled plasma spectrometer. It was found that a small amount of gold had a positive effect on the catalytic cracking of light diesel oil and increased propylene production at a relatively low temperature. The maintenance of the ZSM-5 MFI structure, pore size distribution and the density of weak and strong acid sites of the Au/ZSM-5 catalysts depended on the preparation parameters and the Au loading. Simultaneous enhancement of the micro-activity and propylene production relies on a synergy between the pore size distribution and the relative intensity of the weak and strong acid sites. A significant improvement in the micro-activity index with an increase of 4.5 units and in the propylene selectivity with an increase of 23.2 units was obtained over the Au/ZSM-5 catalyst with an actual Au loading of 0.17 wt%.

We reported a novel and simple strategy to construct core-shell composite microspheres with fly ash (FA) and Au nanoparticles embedded in polypyrrole (PPy) chains. In an acid medium, activation of FA microspheres, synthesization of Au nanoparticles, and polymerization of PPy were synergistically achieved in one-step green process. The physicochemical characteristics of the Au-PPy/FA composite microspheres were studied by SEM, TEM, FTIR, XRD, TGA and VSM. In the presence of NaBH 4 as a reducing agent, the Au-PPy/FA composite microspheres exhibited highly catalytic efficiency in reduction of nitrophenol to aminophenol. The reaction rate constants were calculated through the pseudo-first-order kinetic equation by using the excess amount of NaBH 4 . For the two isomers of nitrophenol, the reduction rates were particularly investigated and followed the order: 4-nitrophenol > 2-nitrophenol. The electronic interaction between Au nanoparticles and PPy chains plays an important role for the highly catalytic efficiency of the Au-PPy/FA. A possible reaction mechanism for the reduction process was also emphasized.

A luminescent biosensor has been developed for matrix metalloproteinase 9 (MMP-9) assays based on the selective interaction between an Ir(iii) solvent complex and a histidine-rich peptide, which avoids the complicated double labeling of substrate polypeptides commonly-used in FRET MMP detections and provides a promising strategy for MMP detection in clinical applications.

Klebsiella pneumoniae is the causative agent of Klebsiella pneumonia and enteritis, and the prevalence of antibiotic resistant strains is becoming a serious public health problem. In this study, we isolated a novel strain of Paenibacillus polymyxa from the fecal extracts of healthy dogs that were challenged with K. pneumoniae. By combination of transposon mutagenesis and metabolic analysis, a nonribosomal peptide synthase gene cluster was identified to be involved in the antagonism, and the molecular weight of the compound was 1168.38 g/mol. These findings will enlarge the arsenal against drug-resistant pathogens.