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Wear behavior of a single-phase laser-clad Cu-9Ni-6Sn coating was investigated against high-carbon steel ball in a ball-on-disc linear wear tester in air and in a 3.5 wt.% NaCl solution, compared with the commercial wear-resistant Cu-10Ni alloy. The wear resistance of a single-phase laser-clad Cu-9Ni-6Sn coating was higher than that of Cu-10Ni alloy in both air and NaCl solution. For the sliding process in air, a continuous, compacted and adherent oxide layer was formed on the sliding surface of Cu-9Ni-6Sn coating due to the combined effects of spinodal decomposition, Sn-rich precipitates and grain refinement. In contrast, such a layer was not seen on the sliding surface of Cu-10Ni alloy. For the sliding process in NaCl solution, Cu-9Ni-6Sn coating exhibited the high hardness and excellent corrosion resistance compared to Cu-10Ni alloy, which was responsible for the better wear resistance of Cu-9Ni-6Sn coating. Clearly, a single-phase laser-clad Cu-9Ni-6Sn coating exhibited the high wear resistance in both air and NaCl solution, resulting in the excellent application prospect in many industries.

It is still challenging how to selectively and sensitively detect cysteine in living systems which plays crucial roles in many physiological and biological processes. Here, we developed a deep-red emission fluorescent probe (DRP-Cys) for Cys based on a hemicyanine scaffold. A tailed malononitrile group could chromatically shift excitation/emission wavelengths to avoid the limitations such as photo-damage or auto-fluorescence in biological samples. Compared with other amino acids, Cys could trigger the Michael addition reaction to release a dramatic enhancement in fluorescence centering at around 645 nm in DMSO aqueous solution under physiological conditions with an ultrafast response time of about 1 min and a low limit of detection of 10 nM which significantly benefited from the introduction of the malononitrile moiety. The probe was also successfully applied for visualizing endogenous Cys in living HeLa cells and mice with low cytotoxicity and good cell-membrane permeability.

The soil and water conservation ratio (SWCR), which is a quantitative index for measuring the control degree of soil and water loss, is equal to the percentage of the land areas with a slight erosion intensity in the study area. The dynamic change in the SWCR reflects the dynamic process of realizing a specific soil and water conservation goal in a certain stage. The objectives of this study were to evaluate the change in the SWCR in the Guizhou Province in this century and to analyze its causes. The temporal and spatial variations of soil erosion intensity and SWCR were measured based on GIS technology and revised universal soil loss equation (RUSLE). The results showed that the spatial pattern of soil erosion intensity in the Guizhou Province was high in the west and low in the southeast, and that the soil erosion characteristics were obviously different between karst and non-karst areas. In the karst areas, the land with a moderate and above erosion intensity (>3 t hm−2 y−1 in the karst area; >25 t hm−2 y−1 in the non-karst area) accounted for 28.20–34.78% of the total area, while only accounting for 2.39–2.72% in the non-karst areas. From 2000 to 2019, the mean intensity of soil erosion decreased from 13.97 to 10.83 t hm−2 y−1, and the SWCR increased from 32.95% to 35.31%. According to the change in erosion intensity grades, 22.30% of the whole province’s erosion grade changed from high to low, especially in the west, with a high erosion intensity. Meanwhile, about 11.99% of the land in the central, eastern and southeastern regions, was where the erosion intensity showed a slight increase and the spatial distribution showed sporadic patch distribution characteristics, which may be related to an increase in infrastructure investment in the Guizhou Province in recent years. A large number of production and construction projects caused the destruction of surface vegetation and also caused patchy soil erosion. The spatial and temporal characteristics of the soil erosion and the SWCR in the Guizhou Province between 2000 and 2019 were mastered through this study, and our results provide an important basis for further scientific and reasonable soil and water conservation planning work.

Hydrophobic treatment is an important method to improve the waterproof properties of concrete. To evaluate the effectiveness of hydrophobic treatments on improving the salt frost resistance of concrete, two representative commercial ordinary water repellent agents of silane and organosilicone emulsion were selected, and concrete specimens with three water/cement ratios were fabricated. After the application of repellent agents on concrete surfaces, accelerated saline (5% MgCl2) freeze-thaw cycles were conducted on the specimens. The mass losses and relative dynamic modulus of elasticity (RDME) of concrete were tested periodically. The contact angles and water absorption ratios of concrete with and without hydrophobic treatments were also tested. Results showed that the repellent agents could substantially enhance the hydrophobicity of concrete and greatly reduce its water absorption. Different repellent agents exerted diverse improvements on concrete hydrophobicity. Meanwhile, the repellent agents could improve concrete resistance against salt scaling and RDME losses to a certain degree, and concrete with strong hydrophobicity showed relatively high salt frost resistance. However, the ordinary water repellent agents cannot achieve the same enhancement on salt frost resistance of concrete as that on the water hydrophobicity of concrete. With saline freezing and thawing cycles, the hydrophobic layer formed by the repellent agents on superficial concrete was destroyed gradually. As a result, the salt frost resistance of concrete from the hydrophobic treatments was ultimately lost.

As the second most abundant transition metal after iron in biological systems, Zn2+ takes part in various fundamental life processes such as cellular metabolism and apoptosis, neurotransmission. Thus, the development of analytical methods for fast detection of Zn2+ in biology and medicine has been attracting much attention but still remains a huge challenge. In this report, we develop a novel Zn2+-specific light-up fluorescent probe based on intramolecular charge transfer combined with chelation enhanced fluorescence induced by structural transformation. Addition of Zn2+ in vitro can induce a remarkable color change from colorless to green and a strong fluorescence enhancement with a red shift of 43 nm. Moreover, the probe shows an extremely low detection limit of 13 nM and ultra-fast response time of less than 1 s. The Zn2+ sensing mechanism was fully supported by TDDFT calculations as well as HRMS and 1H NMR titrations. The recognition of Zn2+ in living Hela cells as well as the MTT assay demonstrate that the probe can rapidly light-up detect Zn2+ in vivo with low cytotoxicity and good cell-permeability. Furthermore, the probe can also be successfully applied to bioimaging Zn2+ in living zebrafish.

Hydrazine is an important reactive base in chemistry, pharmacy and agriculture and an effective propellant in aeronautics and astronautics. However, tiny leakage might induce serious environmental contamination and fatal biological damage. Thus, how to rapidly detect hydrazine with high selectivity and sensitivity is of significance and challenge. In this report, we demonstrate a hydrazine-specific fluorescent probe on the modulation of intramolecular charge transfer process. This probe contains a 4-bromobutyl group as a recognition site for hydrazine anchored on the fluorescent dye. Leaving of 4-bromotutylate moiety leads to a marked NIR fluorescent emission at 715 nm induced by hydrazine. Additionally, presence of hydrazine leads to a color change from green to blue-purple and a ratiometric UV–vis absorption change with a clear isosbestic point at 635 nm. The good linear relationship between fluorescence intensity and concentration of hydrazine results in a low detection limit of 5.09 ppb. The color and fluorescence two-output signals are preferable for qualitative and quantitative detection of hydrazine with high sensitivity and specificity. More importantly, the probe is also successfully applied to visualize hydrazine in living both cells and mice.

As a second messenger, hydrogen peroxide plays significant roles in numerous physiological and pathological processes and is related to various diseases including inflammatory disease, diabetes, neurodegenerative disorders, cardiovascular disease and Alzheimer's disease. Two-photon (TP) fluorescent probes reported for the detection of endogenous H2O2 are rare and most have drawbacks such as slow response and low sensitivity. In this report, we demonstrate a simple H2O2-specific TP fluorescent probe (TX-HP) containing a two-photon dye 6-hydroxy-2,3,4,4a-tetrahydro-1H-xanthen-1-one (TX) on the modulation of the ICT process. The probe exhibits a rapid fluorescent response to H2O2 in 9min with both high sensitivity and selectivity. The probe can detect exogenous H2O2 in living cells. Furthermore, the probe is successfully utilized for imaging H2O2 in liver tissues.

Nerve agents such as Sarin, Soman and Tabun are all very toxic organophosphorus (OP) compounds capable of being used as chemical weapons. Unfortunately, the ability to rapidly sense OPCs is still an ongoing challenging. In this report, we designed and synthesized a fast-response fluorescent probe ( 1 ) for the detection of OP nerve agent simulants with high selectivity and sensitivity. The probe contains an electron donor-to-acceptor system in which a BODIPY moiety acts as a reporter group and the hydroxyl group as a reaction site for nerve agent simulants. The electron deficient nitrile group was introduced to lower the background fluorescence of the probe. A significant enhancement of fluorescence intensities at 531 nm was observed upon gradual addition of nerve agent simulants on excitation at 480 nm. The emission intensity rapidly reached its maximum within only 540 s on adding 6 equiv. of nerve agent simulants with a quantum yield of the reaction product of 0.808, 81-fold larger than the probe itself (Ф = 0.01). A color change in following a paper test experiment verified its portable application.

A novel formation mechanism according to the oxidative dehydrogenation of organics has been proposed for the low-temperature preparation of carbon-based nanomaterials. Several typical organics including ethanol, 1-butanol, p-cymene and liquid paraffin are used as precursors to react with ammonium persulfate (APS) in an autoclave, and carbon particles are obtained as a validation. The reaction characteristics are comprehensively investigated by the differential scanning calorimetric and thermogravimetric analysis. The strongly exothermic oxidation reaction below 200 °C is a common feature during the process. The organic molecules are cleaved into small carbon species and further transform to amorphous carbon. When the organometallic compound is used as a reactant instead, such as magnesocene and allyltriphenyltin, carbon encapsulated MgO and SnS nanocrystals with core-shell structure are synthesized, respectively. A detonation introduced by the violent reaction occurs in the process with a very rapid liberation of heat and large quantities of thermally expanding gases. The large amounts of free atomic/radical species and reactive intermediates are generated as sources for the core-shell structure. It is a common strategy for the large scale production of carbon encapsulated oxide/sulfide nanocrystals by means of the moderate detonation process of the organometallic compound and APS in an autoclave.

Zn2+ plays fundamental roles in cellular metabolism and apoptosis, as well as neurotransmission. However, how to fast detect Zn2+ in biology is still challenging and meaningful. In this study, we rationally synthesized a simple OFF–ON fluorescent probe for fast detection of Zn2+ based on intramolecular charge transfer and chelation-enhanced fluorescence. Addition of Zn2+ into the probe induced a significant fluorescence enhancement with a bathochromic shift of 55 nm. Moreover, the probe demonstrated excellent sensitivity (detection limit = 0.072 μM) and outstanding selectivity toward Zn2+ and an ultra-fast response rate of two seconds. The recognition mechanism of the probe toward Zn2+ was fully confirmed by HRMS and 1H NMR spectra, as well as TDDFT calculations. Furthermore, the probe could rapidly visualize Zn2+ in living cells and zebrafish models in bioimaging experiments with low cytotoxicity and good biocompatibility.

(Ti, W)C reinforced stainless steel coatings were fabricated by plasma cladding for investigating the role of (Ti, W)C particles on microstructure, cyclic oxidation and high-temperature wear resistance of the coatings. (Ti, W)C particles were uniformly dispersed in the coatings and exhibited a diffusion-metallurgical bond with the (Fe, Ni) matrix. Although adding (Ti, W)C to the coating reduced the oxidation resistance due to the low thermal stability of these carbides, the rapid formation and thickening of oxide scale could alleviate the sticking problem in actual rolling condition. Moreover, (Ti, W)C addition resulted in the rapid formation and excellent maintenance of the tribo-oxide glaze during the sliding process, which remarkably improved the wear resistance and reduced the coefficient of friction.

The effect of solution pH, Cl− concentration and temperature on the electrochemical corrosion behavior of PH13-8Mo steel in acidic solution was investigated by using the electrochemical tests, scanning electron microscopy and X-ray photoelectron spectroscopy. The PH13-8Mo martensitic precipitation hardened stainless steel is in the passivity state when the pH value is above 3.0, below which the anodic polarization curves of the steel are actively dissolved. The corrosion current density gradually decreases with increasing the solution pH and decreasing Cl− concentration and solution temperature. Pits are initiated on the sample surface in the presence of the Cl− and gradually developed into uniform corrosion with increasing the Cl− concentrations. Moreover, the corrosion is more serious with an increase in solution temperature.

Fluoride ions are extensively found in aqueous solution, body fluids and tissues, and play an important function in life, so the detection and stable imaging of fluoride ions in living organs is of considerable importance. Herein, we designed and synthesized a new two-photon probe TXS to detect fluoride ions in aqueous solution with turn-on fluorescence. The chemical probe was constructed from tetrahydroxanthenone with a Si O bond to provide excellent selectivity for fluoride ions. Based on the emission properties of tetrahydroxanthenone, two-photon microscopy (TPM) was applied to image fluoride ions in the organs, and the results showed good images in liver tissue at a depth of 60 μm. TPM images of TXS supported a feasible application in biological analyses.

The small signal transmitters SO2 can elaborately modulate signal transduction pathways. Endogenous formaldehyde (FA) can toxify protein and DNA as a crosslinking agent besides functions in the aspect of spatial memory and cognitive ability. Both SO2 and FA are tightly associated with neurological disorders, cardiovascular diseases. Therefore, it is significant and challenging to monitor the real-time dynamic fluctuation of SO2 and FA in cells or animals. Toward this end, for the first time, a near-infrared (NIR) dual-emission fluorescent probe (BCou-BP) for SO2 and FA was developed based on the rational combination of benzypylium and benzo[g]coumarin cores through tuning the conjugation and rigidity of the fluorophore units. Thus, this rational design affords the new cationic probe the ratiometric detection ability (F604/F694) toward mitochondrial SO2 with a fast response time of 10 s, as well as toward FA in 170 s. Endogenous FA could restore the fluorescence at 694 nm of BCou-BP due to the capture of SO2 from decomposition of the adduct BCou-BP-SO3H. The powerful probe succeeded in real-time visualizing the dynamic change of endogenous mitochondrial SO2 and FA in living cells and mice.

A novel bipyridine-functionalized turn-on fluorescent chemosensor was successfully synthesized and fully characterized by 1 H NMR, 13 C NMR and MS, UV–vis and fluorescence spectroscopies. The sensor specifically binds to Hg 2+ over other competing ions with a significant fluorescence enhancement as well as a visual colour change under physiological conditions. The detection limit of Hg 2+ was as low as 32 nM, confirming very high sensitivity toward Hg 2+ . Moreover, the fluorescence intensity and colour change of the sensor-Hg 2+ was quenched by I − or S 2− and was proportional to their concentrations with a detection limit of 0.37 μM and 0.43 μM, respectively. The reaction of I − grabbing Hg 2+ from the sensor–Hg 2+ finished in 10 s due to a stronger binding force, much faster than that of S 2− , which allowed fast detection of I − over S 2− even in a competent environment. In addition, the sensor was successfully used for the highly sensitive detection of Hg 2+ in living cells.

Intracellular biothiols are correlated with many diseases such as nerve disorder and Parkinson’s disease likely due to a redox imbalance. In this work, we designed an ultrafast fluorescent probe (Cou-DNBS) for biothiols with a large Stokes shift (131 nm). The probe was constructed through linking the 2,4-dinitrobenzenesulfonyl moiety as the specially recognizing biothiols site to an iminocoumarin fluorophore Cou-NH obtained by fusing an additional benzene ring. The presence of biothiols could ultrafast perform a significant fluorescence emission at 617 nm upon the excitation of 480 with the low limits of detection (2.5 nM for Cys, 1.7 nM for Hcy and 0.84 nM for GSH). HRMS spectra as well as theoretical calculations further evidenced the rationale of recognition mechanism. Furthermore, the probe can successfully visualize endogenous biothiol recovery in living cells damaged by H2O2.

Two novel colorimetric and fluorescent off-on enantiomers (R/S-RBOL) were developed to detect Fe3' in aqueous and biological samples through probing the integrated changes in fluorescence, circular dichroism (CD) and circularly polarized luminescence (CPL). The fluorescence intensity of R/S-RBOL is linearly proportional to the Fe3+ concentration in the range of 0-20 equiv., bringing out a detection limit of 1.83 x 10(-7)M. The Job's plot indicates a 1:1 binding stoichiometry of RBOL:Fe3+, which is further confirmed by ESI-MS analysis. Moreover, the RBOLs exhibit a dual-readout response in colour and fluorescence, rendering them suitable to sense Fe3+ in living cells with low cytotoxicity. In order to shed some light on the detection mechanism, the coordination between R/S-RBOL and Fe3+ is unravelled by DFT calculations. From the free RBOL to the RBOL-Fe3+ complex, the spiro-lactam ring is opened to interact with Fe3+ via the lactam N and O, imine N and hydroxyl 0 atoms in the form of a ferric six-coordinate structure. (C) 2015 Elsevier B.V. All rights reserved.

TiC–Cr7C3–CNTs cermet coating on 304 stainless steel substrate was prepared using a newly developed in situ technology consisting of self-propagation high-temperature synthesis reaction, laser cladding and metal dusting techniques. The samples were subjected to various microstructure examinations and their corrosion behaviour was compared with that of 304SS in 1 mol L− 1 HCl solution. The results showed that high quality of the coating was obtained. Many reinforcements were more or less uniformly distributed within the grain and grain boundary in the microstructure. Carbon nanotubes (CNTs) were obviously observed, but the length of CNTs was shorter after laser cladding. Compared with the 304SS substrate, the coating has no pitting and maintained a low corrosion rate in 1 mol L− 1 HCl solution.

A ratiometric and on–off fluorescent chemosensor (PB) containing a pyrene moiety was designed and synthesized for the selective detection of trivalent chromium ion over other common metal ions using an intramolecular-charge transfer (ICT) mechanism. The fluorescence emission intensities showed a significant decrease of the emission intensity at 425 nm and formation of a new band at 594 nm upon excitation at 343 nm. A well-defined isoemissive point was observed at 564 nm with increasing Cr3 + concentration. The emission ratios (F425/F594) showed good linearity with Cr3 + concentration thereby allowing the detection of Cr3 + using a ratiometric fluorescence method with a detection limit of 0.23 μM. A Job plot indicated a 1:1 binding stoichiometry with an association constant (Ka) of 7.52 × 104 M− 1, which was further confirmed by MALDI-TOF analysis.

A novel method is developed for the synthesis of carbon co-encapsulated near-equiaxed NiS2, NiS and S8 nanocrystals with core–shell structure by a one-step solid state reaction of nickelocene with ammonium persulphate at 200 °C in an autoclave. These nanocrystals have a narrow size distribution ranging from 5 to 19 nm and the median size is 10.99 nm. Both amorphous and graphitizable carbon shell are formed, encapsulating hundreds of nanocrystals as a whole and providing exclusive rooms for these nanocrystals separated from each other. The interaction of nickel with cyclopentadienyl ligands through π bond results in the formation of core–shell structure. The carbon encapsulated NiS2 and NiS nanocrystal anodes retain a reversible capacity of 517 and 326 mA h/g after 50 cycles at a current density of 208 and 1480 mA/g, respectively.

In attempts to investigate the photoluminescent properties of the Cd and Pb-based materials, two new microporous 3D metal organic frameworks (MOFs) [Cd2(pdt)(H2O)2]n (1) and [Pb4(pdt)(aip)2(H2O)4]n (2) (pdt = 1,3-propanediaminetetraacetate anion; aip = 5-aminoisophthalate anion) with different network topologies have been hydrothermally synthesized by introducing the organic base imidazole. The 3D MOFs were insoluble in water and were structurally characterized by elemental analysis, FT-IR spectra, thermogravimetric analyses, and X-ray powder diffraction techniques. Examples of the MOFs assembled from pdt mixed with other auxiliary ligands have not been reported so far. Compared with the free ligands, the photoluminescent properties of 1 and 2 were also studied in the solid state at room temperature. A promising avenue for rational design of such Cd and Pb-based photoluminescent MOFs with 1,3-propanediaminetetraacetate ligand and its auxiliary ligand would open for further research.

Blends of high density polyethylene (HDPE) and ultra-high molecular weight polyethylene (UHMWPE) were prepared by melt blending, and then the high temperature melting (HTM) and subsequent shear were used to improve the integration of HDPE with UHMWPE. Based on accelerating diffusion of polymer chains at high temperature, our hypothesis was that the HTM could enhance chains diffusion across the phase interface, thus the integration of HDPE with UHMWPE components could be improved. An important finding of this study was that melting HDPE/UHMWPE blends at 280 °C in inert atmosphere improved the swelling of UHMWPE by HDPE and enhanced the phase interaction. And then a subsequent shear resulted in a better integration of HDPE with UHMWPE components than that by a conventional process.

Based on an attempt to investigate the influence of solvents and counteranions on the structures and photoluminescence properties of Pb-based metal–organic frameworks, the hydrothermal reactions of the same amounts of Pb(NO3)2 and Pb(OAc)2 with the ligand 5-tert-butylisophthalic acid (H2tip) in the presence of water and a water–ethanol mixture have yielded three compounds [Pb(H2O)(tip)]n (1), [Pb3(μ4-O)(tip)2]n (2) and [Pb4(μ4-O)(tip)3]n (3) under similar reaction conditions (tip = 5-tert-butylisophthalate anion). These compounds represented the first examples of Pb(II) metal–organic frameworks with H2tip. All of them have been characterized by means of FT-IR spectra, elemental analysis, single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis, and photoluminescence spectra. The reaction processes revealed that 1 and 2 had selectivity for specific solvents. And the selectivity for specific counteranions was also found in 2 and 3. Single-crystal X-ray diffraction showed that 1 and 3 crystallized in the orthorhombic crystal system with space groups of Iba2 and Pna21, respectively, while 2 crystallized in the monoclinic P21/c space group. The structure of 1 featured a 2D bilayer structure containing a uninodal sql-type topological motif with a Schlafli symbol of (44). The 2D layer framework of 2 was constructed from a unique 8-connected hexanuclear cluster secondary building unit Pb6O2(COO)8, resulting in a uninodal hxl-type topological motif with a Schlafli symbol of (36·46·53). The structure of 3 could be described as a 3D microporous framework with a 6-connected tetranuclear cluster Pb4O(COO)6. Topological analysis revealed that 3 represented a uninodal dia-type topological motif with a Schlafli symbol of (66). All of the solid state compounds exhibited the photoluminescence properties at room temperature. Furthermore, taking the emissions of the free ligand into consideration, the emissions 1 and 2 could be assigned to metal-centered s → p transition transitions, while the emissions of 3 were due to ligand-to-metal charge transfers between the delocalized p bonds of carboxylate groups and p orbitals of Pb(II) centers. Especially, the in situ solvent and counteranion-induced synthesis strategy reported here could afford us new opportunities in the rapid design of new materials with interesting structures and properties.

A fast-response, highly selective and sensitive chemosensor, 3, for Cr3+ detection with turn-on fluorescence behavior in the physiological pH range was designed and synthesized. The chemosensor contained a combined push–pull system in which the fluorescent phenanthro[9,10-d]oxazole moiety acts as both an electron donor and a potential binding site. The electron deficient nitrile group served as an electron acceptor. A significant enhancement of fluorescence emission intensities was observed with increasing Cr3+ concentration upon excitation at 300 nm. The emission intensity reached its maximum on adding 8 equiv. of Cr3+ where the quantum yield of 3-Cr3+ was found to be 0.917, ca. 7-fold larger than chemosensor 3. The selectivity mechanism of 3 for Cr3+ was found to be based on the combined effects of the inhibition of ICT and CHEF. Remarkably the entire process was virtually complete in only 10 seconds, with a minimum detection limit for Cr3+ of 1.72 × 10−8 M−1.

Hydrazine is carcinogenic and highly toxic so that it can lead to serious environmental contamination and serious health risks although it has been extensively used as an effective propellant and an important reactive base in industry. Thus, the development of two-emission NIR fluorescent probes for rapid detection of hydrazine with high selectivity and sensitivity is of significance and of great challenge in both biological and environmental sciences. Here, we report a two-emission colorimetric fluorescent probe for the specific detection of hydrazine based on hydrazinolysis reaction under physiological conditions. In the presence of hydrazine, the probe showed an extremely remarkable fluorescence enhancement at 627 nm compared to the decrease at 814 nm excited at different wavelength in aqueous solution. This distinct difference of two emission intensities is suitable for detection of low concentration hydrazine with a detection limit of 0.38 ppb. Addition of hydrazine resulted in a remarkable color change from blue-green to red observed by the naked eye. Kinetic study indicated a fast response of the probe toward hydrazine in minutes. Furthermore, the probe can bioimage hydrazine in living HeLa cells and mice with low cytotoxicity and excellent biocompatibility.

The trinuclear NiII cluster [Ni3(bpca)2(bpy)2(H2O)4](NO3)4·H2O (1) (bpca– = anion of bis(2-pyridylcarbonyl)amine, bpy = 2, 2′-bipyridine) was isolated. Single crystal X-ray diffraction analysis showed that three crystallographically independent NiII ions are located in a six-coordinate distorted octahedral environment, bridged by the organic spacer bpca–. The crystal lattice is stabilized by hydrogen bonds, which are linking the Ni3 cations and NO3– anions into a three-dimensional framework. Variable-temperature magnetic susceptibility for complex 1 in the range 2–300 K indicates the presence of weak antiferromagnetic interactions in the Ni3 unit with J = –0.67 cm–1.

A novel chiral dinuclear Cu(II) cluster [Cu 2 (bpca)(bpy)(H 2 O)(NO 3 ) 3 ] ( 1 ) (bpca − is the anion of bis(2-pyridylcarbonyl)amine and bpy is 2,2′-bipyridine), was synthesized and characterized. Single crystal X-ray diffraction analysis showed that the two Cu(II) ions in complex 1 are sitting in a distorted octahedral arrangement and bridged by the organic spacer bpca − . Hydrogen bonding links neighboring dinuclear units into a three-dimensional framework. Inversion crystallographic symmetry gives dimers as either Λ or Δ isomers. Racemization of complex 1 was confirmed by circular dichroism (CD) spectroscopy. The temperature dependence of the magnetic susceptibility for complex 1 in the range 2–300 K indicates the presence of ferromagnetic Cu⋯Cu exchange. The data fitting gave the magnetic coupling constant J = 8.08 cm −1 .

Hierarchical K2Mn4O8 nanoflowers synthesized by a facile, fast, high-yield and low-cost molten salt method (MSM), have been investigated as a photothermal conversion material for solar vapor generation for the first time. Loading K2Mn4O8 into microporous poly(vinylidene fluoride) membrane (PVDFM) forms a K2Mn4O8/PVDFM composite evaporator. This evaporator shows high solar-to-vapor conversion efficiencies of ∼80.8% and ∼91.2% under 1 sun and 4 sun irradiation, respectively, and a stable solar vapor generation performance. Therefore, this evaporator has shown a promising potential for interfacial solar vapor generation.

A novel method is developed for low temperature synthesis of carbon encapsulated spherical Fe 7 S 8 , equiaxed Fe 3 O 4 and spherical porous FeOOH nanocrystals with a core–shell structure via a solid–solid reaction of ferrocene with (NH 4 ) 2 S 2 O 8 , (NH 4 ) 2 Cr 2 O 7 and NH 4 ClO 4 in an autoclave, respectively. Samples were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It is found that the median size of Fe 7 S 8 , Fe 3 O 4 and FeOOH nanocrystals is about 28.99, 52.68 and 25.66 nm, respectively. The hollow worm-like carbon shell provides exclusive rooms for tens to hundreds of nanocrystals separated from each other. The cooperative effect of ammonium and strong oxidizing ion on electrophilic oxidation of ferrocene contributes to the in situ formation of carbon shell on the nanocrystals. The metal–π interaction of iron atom with cyclopentadienone oligomers enables ordered self-assembling of carbon rings, resulting in the formation of graphitizable carbon shell with roughly parallel fringes at low temperature.

A simple and effective way was expected to improve the blending of ultra-high-molecular-weight polyethylene (UHMWPE) in high-density polyethylene (HDPE) matrix. HDPE/UHMWPE blends were subjected to high temperature melting (HTM) at 280°C for up to 10 h, followed by shear at 175°C. These results were examined by scanning electron microscopy, polarized optical microscopy, and melt rheological behavior. UHMWPE particle was swelled partially during HTM, and this swollen region could be peeled from the particle by the subsequent shear, which resulted in more “dissolution” of UHMWPE in HDPE matrix. These results were also validated by the rheological behavior. POLYM. ENG. SCI., 55:270–276, 2015. © 2014 Society of Plastics Engineers

Three cubane Ni(II) and Cu(II) complexes, namely [Cu4L14]·CH3CN (1), [Ni4L14(CH3OH)4]·4H2O (2), [Ni4L24(CH3OH)4]·6H2O (3), have been synthesized from flexible polydentate Schiff bases (H2L1 and H2L2) based on o-vanillin. X-ray single-crystal analyses reveal that all three complexes own a cubane-like core M4O4 in which Cu ions in 1 are five-coordinated and Ni ions in 2 and 3 are six-coordinated. Variable-temperature magnetic susceptibility data display dominant ferromagnetic interactions in complexes 1–3 while antiferromagnetic and ferromagnetic couplings coexist in the cubane core, thus resulting in a nonzero spin ground state. The magnitude of the exchange coupling constants correlates with the geometrical parameters arising from the minor ligand modifications.