Publications by authors named "Ran Shang"

36 Publications

Basic characteristics between mechanomyogram and muscle force during twitch and tetanic contractions in rat skeletal muscles.

J Electromyogr Kinesiol 2022 Jan 3;62:102627. Epub 2022 Jan 3.

Department of Medical Technology, Graduate School of Health Sciences, Okayama University, Okayama, Japan. Electronic address:

The mechanomyogram (MMG) is a signal measured by various vibration sensors for slight vibrations induced by muscle contraction, and it reflects the muscle force during electrically induced-contraction or until 60%-70% maximum voluntary contraction, so the MMG is considered an alternative and novel measurement tool for muscle strength. We simultaneously measured the MMG and muscle force in the gastrocnemius (GC), vastus intermedius (VI), and soleus (SOL) muscles of rats. The muscle force was measured by attaching a hook to the tendon using a load cell, and the MMG was measured using a charged-coupled device-type displacement sensor at the middle of the target muscle. The MMG-twitch waveform was very similar to that of the muscle force; however, the half relaxation time and relaxation time (10%), which are relaxation parameters, were prolonged compared to those of the muscle force. The MMG amplitude correlated with the muscle force. Since stimulation frequencies that are necessary to evoke tetanic progression have a significant correlation with the twitch parameter, there is a close relationship between twitch and tetanus in the MMG signal. Therefore, we suggest that the MMG, which is electrically induced and detected by a laser displacement sensor, may be an alternative tool for measuring muscle strength.
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http://dx.doi.org/10.1016/j.jelekin.2021.102627DOI Listing
January 2022

Application of mixed bacteria-loaded biochar to enhance uranium and cadmium immobilization in a co-contaminated soil.

J Hazard Mater 2021 01 2;401:123823. Epub 2020 Sep 2.

School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China.

This research explored the effect of biochar pyrolyzed from five different materials on U and Cd immobilization in soil. The results showed that all biochars improved the soil properties and microbial metabolic activities, and effectively immobilized U and Cd, especially corn stalk biochar. Subsequently, three strains Bacillus subtilis, Bacillus cereus, and Citrobacter sp. were mixed in a 3:3:2 proportion as a kind of mixed bacteria (MB9) that could adsorb U and Cd effectively. Two types of MB9-loaded biochar were synthesized by physical adsorption and sodium alginate embed method and referred to as AIB and EIB, respectively. MB9-loaded biochar showed superior U and Cd immobilization performance. At 75 d, the highest reduction in the DTPA- extractable U and Cd (69 % and 56 %) was achieved with the 3% AIB amendment. Additionally, compared to the addition of biochar or MB9 alone, AIB was more effective in promoting celery growth and reducing U and Cd accumulation. Finally, the microbial community structure analysis suggested that the relative abundance of Citrobacter genus and Bacillus genus was significantly increased, suggesting that the mixed bacteria MB9 was successfully colonized. These findings may provide a feasible technology for green and cost-effective remediation of heavy metal contamination in farmland soil.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123823DOI Listing
January 2021

A novel self-crosslinked gel microspheres of Premna microphylla turcz leaves for the absorption of uranium.

J Hazard Mater 2021 02 30;404(Pt A):124151. Epub 2020 Sep 30.

School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, Sichuan, China; Engineering Research Center of Biomass Materials, Ministry of Education, Mianyang 621010, Sichuan, China.

Premna microphylla turcz leaves (PMTL) is a resource-rich, biodegradable, renewable biomass. Here, a microsphere adsorbent was prepared from PMTL by a self-crosslinking method without any addition of chemical cross-linking agent, and characterized by SEM, FTIR, and XPS. The influence of preparation methods and conditions on the properties of the microspheres was studied and the self-crosslinking mechanism was analyzed. The effects of temperature, pH, contact time, uranium concentration, and adsorbent dosage on its adsorption performance toward to uranium were systematically explored. The results showed that PMTL endogenous pectin binding with endogenous Ca, Mg and other metal ions to form an 'egg box' structure might be the mechanism of its self-crosslinking to form microspheres. The adsorption isotherms fitted well by the Freundlich model and the experimental maximum adsorption capacity of microspheres was 346.65 mg·g at pH of 5, and kinetics data correlated well with the pseudo-second order model. The adsorption mechanism might be the coordination bonding between the uranium and oxygen-containing groups (hydroxyl and carboxyl groups), and the ion exchange between the uranium and metal ions (mainly Ca and Mg). The PMTL microspheres are promising in treating uranium-containing wastewater in a more cost-effective and environmentally friendly manner.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124151DOI Listing
February 2021

Usage of microbial combination degradation technology for the remediation of uranium contaminated ryegrass.

Environ Int 2020 11 1;144:106051. Epub 2020 Sep 1.

Xinjiang Center for Disease Control and Prevention, Xinjiang 830002, China.

Post phytoremediation accumulation of heavy metals in plants is causing an environmental issue worldwide. In this study, we investigated the ability of eight different kinds of microorganisms to degrade and release heavy metals from heavy metal enriched ryegrass, including 5 species of bacteria (Bacillus subtilis, Bacillus licheniformis, Bacillus pumilus-I, Bacillus pumilus-II and Bacillus cereus) and 3 of fungi (Phanerochaete chrysosporium, Trichoderma ressei and Pterula sp. strain QD-1), by growing them under uranium stress and assessing their ability to degrade biomass. After 30 days, the degradation ability of fungi was found better than that of bacteria, while the metal leaching ability of bacteria was found better. The highest degradation rate (upto 60%) was obtained by using P. chrysosporium, Pterula sp. strain QD-1 exhibited the best leaching rate for uranium (upto 77%). The overall degradation rate of lignin and cellulose and hemicellulose was found lower (40% and 60%, respectively). According to the antagonistic characteristics of microbes, we combined different dominant species, in which under optimal conditions the T2 combination (P. chrysosporium, T. reesei, and Pterula sp. strain QD-1 and B. subtilis) was able to degrade 80% of the ryegrass, 51% of lignin, 74% of cellulose and hemicellulose, releasing 78% of U, 90% of Pb and the releasing rate of other heavy metals was more than 95%. FTIR analysis showed the least degradation of lignin, while SEM-EDX analysis of the degradation residues displayed the microstructure of ryegrass being greatly damaged. Only a small amount of U was found in the residues of the researched combinations. This study provides efficient Microbial Combined Degradation Technology for heavy metal enriched biomass, which can effectively deal with heavy metal enriched plants, and provide a basis for the recovery and utilization of heavy metals, avoiding secondary pollution in the environment caused by this type of biomass.
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http://dx.doi.org/10.1016/j.envint.2020.106051DOI Listing
November 2020

Bile acids aggravate nonalcoholic steatohepatitis and cardiovascular disease in SHRSP5/Dmcr rat model.

Exp Mol Pathol 2020 06 1;114:104437. Epub 2020 Apr 1.

Department of Medical Technology, Graduate School of Health Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama-shi, Okayama 700-8558, Japan. Electronic address:

Background And Aims: Nonalcoholic steatohepatitis (NASH) is linked to an increased risk of cardiovascular disease, regardless of the risk factors in metabolic syndrome. However, the intermediary factors between NASH and cardiovascular disease are still unknown. A previous study revealed that serum and hepatic bile acid (BA) levels are increased in some NASH patients. We aimed to examine whether NASH and cardiovascular disease were aggravated by BA using an animal model.

Method And Results: From 10 to 18 weeks of age, SHRSP5/Dmcr rats divided into 3 groups were fed 3 types of high-fat and high-cholesterol (HFC) diets which were changed in the cholic acid (CA) concentration (0%, 2%, or 4%). The nitro oxide synthase inhibition (L-NAME) was administered intraperitoneally from 16 to 18 weeks of age. The 4% CA groups showed the worst LV dysfunction and myocardial fibrosis, and demonstrated severe hepatic fibrosis and lipid depositions. In addition, a large amount of lipid accumulation was observed in the aortas of the 4% CA group, and NFκB and VCAM-1 gene expression levels were increased. These findings were not seen in the 0% CA group.

Conclusion: In the SHRSP5/Dmcr rat model, NASH and cardiovascular disease were aggravated with increasing BAs concentrations in an HFC diet.
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http://dx.doi.org/10.1016/j.yexmp.2020.104437DOI Listing
June 2020

Graphene Oxide Incorporated Forward Osmosis Membranes With Enhanced Desalination Performance and Chlorine Resistance.

Front Chem 2019 10;7:877. Epub 2020 Jan 10.

Department of Military Facilities, Army Logistics University, Chongqing, China.

In this work, grapheme oxide (GO) nano-sheets were synthesized and dispersed in the aqueous phase for the interfacial polymerization (IP) process to develop a new type of thin-film composite (TFC) membranes for forward osmosis (FO) applications. The effects of the GO concentrations on the membrane surfaces and cross-sectional morphologies and FO desalination performances of the as-prepared TFC membranes were investigated systematically. Compared with the control membrane, the optimal GO-incorporated TFC membrane displayed higher water flux, less specific reverse solute flux (SRSF) and lower structure parameter. Moreover, the optimized membrane showed 75.0 times higher chlorine resistance than the control membrane. In general, these new type of membranes could be an effective strategy to fabricate high-performance FO membranes with good desalination performance and chlorine resistance.
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http://dx.doi.org/10.3389/fchem.2019.00877DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6965320PMC
January 2020

Carboxymethyl konjac glucomannan mechanically reinforcing gellan gum microspheres for uranium removal.

Int J Biol Macromol 2020 Feb 26;145:535-546. Epub 2019 Dec 26.

State Key Laboratory of NBC Protection for Civilian, 102205 Beijing, China.

Biosorbents have been a promising adsorbent to remove uranium while their poor mechanical properties prevent them from being widely used in practice. In this study, carboxymethyl konjac glucomannan (CMKGM) was incorporated to gellan gum to form a double-network gel micro spheres (CMKGM/GG-Al) for uranium removal with its mechanical strength fairly being reinforced. The compressive strength of the CMKGM/GG-Al microspheres was about 6 times than that of GG-Ca microspheres we prepared before while the adsorption capacity still be at a better value with the fitting maximum adsorption capacity being of 97.94 mg/g. Its uranium adsorption properties were investigated by considering the influence of pH, the adsorbent dosage, temperature, initial uranium concentration, time and coexisting ions. The adsorption mechanism was also investigated according to the SEM, EDX, FT-IR and XPS data analysis. The isotherm equilibrium data which were best fitted with Langmuir model and the kinetics data which were best fitted with pseudo-second-order model. It was inferred that the adsorption process was mainly the ion-exchange and the coordination with hydroxyl groups on the adsorbent surface and the adsorption process was endothermic and spontaneous. The CMKGM/GG-Al microspheres prepared in this study would be more conducive to practical application for uranium removal.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.12.188DOI Listing
February 2020

Rapid removal of diclofenac in aqueous solution by soluble Mn(III) generated in a novel Electro-activated carbon fiber-permanganate (E-ACF-PM) process.

Water Res 2019 Nov 12;165:114975. Epub 2019 Aug 12.

Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, 80401, USA.

Electrolysis and permanganate (PM) oxidation are two commonly used technologies for water treatment. However, they are often handicapped by their slow reaction rates. To improve the removal efficiency of refractory contaminants, we combined electrolysis with PM using an activated carbon fiber (ACF) as cathode (E-ACF-PM) for the first time to treat diclofenac (DCF) in aqueous solution. Up to 90% DCF was removed in 5 min by E-ACF-PM process. In comparison, only 3.95 and 27.35% of DCF was removed by individual electrolysis and PM oxidation at the same time, respectively. Acidic condition was more conducive to DCF removal. Surprisingly, soluble Mn(III) formed on the surface of ACF was demonstrated as the principal oxidizing agent in E-ACF-PM process. Further studies showed that all three components (electrolysis + ACF + PM) were necessary to facilitate the heterogeneous generation of reactive Mn(III) . Moreover, SEM images and XPS spectra of ACF before and after treatment revealed that the morphologies and elemental compositions of reacted ACF were nearly unchanged during the E-ACF-PM process. ACF can be remained active and utilized to the rapid degradation of DCF in E-ACF-PM process even after reused for 20 times. Therefore, the E-ACF-PM process may provide a novel and effective alternative on the generation of reactive Mn(III) in situ for water treatment by green electrochemical reactions.
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http://dx.doi.org/10.1016/j.watres.2019.114975DOI Listing
November 2019

Preparation of tannin-immobilized gelatin/PVA nanofiber band for extraction of uranium (VI) from simulated seawater.

Ecotoxicol Environ Saf 2019 Apr 30;170:9-17. Epub 2018 Nov 30.

Engineering Research Center of Biomass Materials, Ministry of Education, Mianyang 621010, Sichuan, China.

A novel gelatin/PVA composite nanofiber band loaded with bayberry tannin (GPNB-BT) was prepared by electrostatic spinning and crosslinking for extraction of uranium (VI) from simulated seawater. The influential factors of tannin loaded on the nanofiber band were investigated in detail. Surface morphology and fiber diameter of GPNB-BT were studied by Scanning Electron Microscopy (SEM). Functional groups of GPNB-BT were investigated by Fourier Transform Infrared Spectrometer (FTIR). The adsorption process and mechanism of uranium on GPNB-BT was characterized by Energy Dispersive X-ray (EDX) and X-ray Photoelectron Spectroscopy (XPS). The results revealed that the BT had been stably solidified on the GPNB. Compared with other tannin-immobilized membranes, the nano-network structure of GPNB-BT with 200-400 nm diameter of fibers can promote solidification of tannins and improve adsorption capacity of GPNB-BT for uranium. The maximum adsorption capacity of the GPNB-BT for uranium is 170 mg/g at the optimal pH of 5.5 in 80 mg/L of initial uranium concentration and 1.4 μg/g even at extremely low initial concentration of 3 μg/L in the simulated seawater for 24 h. The GPNB-BT with good hydraulic properties, floatability and adsorption capacity for uranium is expected to be widely used in separation and enrichment of uranium in seawater and radioactive waste water.
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http://dx.doi.org/10.1016/j.ecoenv.2018.11.089DOI Listing
April 2019

Study on adsorption of tetracycline by Cu-immobilized alginate adsorbent from water environment.

Int J Biol Macromol 2019 Mar 27;124:418-428. Epub 2018 Nov 27.

Academy of Military Sciences PLA China, Beijing 100000, China.

Widespread concern had been given raise to the pollution of antibiotics including tetracyclines in water environment in recent years. A novel Cu-immobilized alginate adsorbent had been synthesized successfully through a facile fabrication way called sol-gel method, and its adsorption performance had been investigated for the tetracycline removal at various conditions, including the pH, temperature, the dosage of adsorbent, concentration and contact time. The adsorbent was characterized with SEM, EDX, FT-IR and XPS analyses to confirm its properties before and after adsorption. The equilibrium data was fitted well with the Freundlich isotherm model and the maximum adsorption capacity for tetracycline was 53.26 mg·g at pH 3, 318.15 K, and 90 mg·L tetracycline solution. The pseudo-second-order kinetic and Freundlich isotherm models combining with the correlative analysis implied that the tetracycline adsorption onto the Cu-immobilized alginate adsorbent was administrated by the n-π electron-donor-acceptor interaction (n-π EDA interaction), hydrogen bond and the cation bonding bridge. Moreover, thermodynamic study demonstrated that the nature of tetracycline adsorption was endothermic, feasible and spontaneous. Compared with the other adsorbents, the as-prepared adsorbent had an excellent tetracycline adsorption capacity, and was expected to be widely applied in the adsorption treatment of tetracycline wastewater.
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http://dx.doi.org/10.1016/j.ijbiomac.2018.11.218DOI Listing
March 2019

High-silica zeolites for adsorption of organic micro-pollutants in water treatment: A review.

Water Res 2018 11 7;144:145-161. Epub 2018 Jul 7.

Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, 2600, GA Delft, The Netherlands.

High-silica zeolites have been found to be effective adsorbents for the removal of organic micro-pollutants (OMPs) from impaired water, including various pharmaceuticals, personal care products, industrial chemicals, etc. In this review, the properties and fundamentals of high-silica zeolites are summarised. Recent research on mechanisms and efficiencies of OMP adsorption by high-silica zeolites are reviewed to assess the potential opportunities and challenges for the application of high-silica zeolites for OMP adsorption in water treatment. It is concluded that the adsorption capacities are well-related to surface hydrophobicity/hydrophilicity and structural features, e.g. micropore volume and pore size of high-silica zeolites, as well as the properties of OMPs. By using high-silica zeolites, the undesired competitive adsorption of background organic matter (BOM) in natural water could potentially be prevented. In addition, oxidative regeneration could be applied on-site to restore the adsorption capacity of zeolites for OMPs and prevent the toxic residues from re-entering the environment.
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http://dx.doi.org/10.1016/j.watres.2018.07.017DOI Listing
November 2018

A Series of Bimetallic Ammonium AlNa Formates.

Chemistry 2017 Jul 29;23(41):9857-9871. Epub 2017 Jun 29.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.

A series of AlNa bimetallic ammonium metal formate frameworks (AlNa AMFFs) have been prepared by employing various ammoniums from NH to large linear polyammoniums. The series consists of six perovskites of (4 ⋅6 ) topology for mono-ammoniums, two chiral (4 ⋅6 ) frameworks incorporating polyethylene ammoniums, two niccolites with (4 ⋅6 )(4 ⋅6 ) topology containing diammoniums, and two layered compounds made of 2D (4,4) AlNa formate sheets intercalated by small diammoniums. The first ten compounds present the structural hierarchy of (4 ⋅6 ) (4 ⋅6 ) framework topologies for (m, n)=(1, 0), (0, 1), and (1, 1), respectively, in parallel to the homometallic AMFFs for divalent metals. The symmetry lowering, asymmetric formate bridges, and different hydrogen-bonding strengths appeared in the bimetallic structures owing to the different charge and size of Al and Na seemingly inhibits the occurrence of phase transitions for more than half the AlNa AMFFs within the series, and the bimetallic members undergoing phase transitions show different transition behaviors and dielectric properties compared with the homometallic analogs. Anisotropic/negative/zero thermal expansions of the materials could be rationally attributed to the librational motion, or flip movement between different sites, of the ammonium cations, and the coupled change of AlNa formate frameworks. The thermal and IR spectroscopic properties have also been investigated.
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http://dx.doi.org/10.1002/chem.201701099DOI Listing
July 2017

Heat-activated persulfate oxidation of methyl- and ethyl-parabens: Effect, kinetics, and mechanism.

Chemosphere 2017 Feb 2;168:1628-1636. Epub 2016 Dec 2.

School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, China; Key Laboratory of Water & Wastewater Treatment (HUST), MOHURD, Wuhan 430074, China.

We evaluated the degradation of methylparaben (MeP) and ethylparaben (EtP), two representative parabens, using the heat-activated persulfate system in a laboratory. Both sulfate and hydroxyl radicals contributed to the removal of the two parabens. The degradations of both MeP and EtP were improved by increasing the heating temperature or persulfate dose in accordance with a pseudo-first-order reaction model. The oxidation efficiency of parabens was found to be pH-dependent; decreasing in the order pH 5.0 > 7.0 > 9.0. The presence of chloride, bicarbonate, or humic acid was found to inhibit the degradation of the two parabens to some extent because of competition for the reactive radicals, with humic acid having the most serious effect. Dealkylation of the methyl unit, decarboxylation of the carboxylic group, and subsequent hydrolysis are proposed to be involved in the degradation pathway of MeP. The results suggest that the heat-activated persulfate system might be efficiently applied in the treatment of paraben-containing water samples. This was also supported by the results of applying this system to treat a real water sample containing both MeP and EtP.
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http://dx.doi.org/10.1016/j.chemosphere.2016.11.143DOI Listing
February 2017

UV/persulfate preoxidation to improve coagulation efficiency of Microcystis aeruginosa.

J Hazard Mater 2017 Jan 11;322(Pt B):508-515. Epub 2016 Oct 11.

School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, China; Key Laboratory of Water and Wastewater Treatment (HUST), MOHURD, Wuhan, 430074, China.

The performance of UV-activated persulfate (UV/PS) technology as preoxidation process to enhance Microcystis aeruginosa removal by subsequent coagulation-sedimentation was firstly evaluated. The results demonstrate that UV/PS preoxidation could successfully promote coagulation of algae cells through the effective neutralization of zeta potential, which was caused by the changes of cell morphology, size distribution and surface properties after simultaneous UV irradiation and formed reactive species (i.e. SO and HO) oxidation. Since excessive oxidation would cause cell rupture along with the release of organics, which could deteriorate coagulation efficiency, optimal PS dose (60mg/L) and UV dose (375mJ/cm) were proposed to exist in this study. The concentrations of extracellular algal organic matter (AOM) sharply increased by 48.2% during the preoxidation period, while gradually decreased in the following coagulation and sedimentation. Most of the concerned disinfection by-products (DBPs) monotonically decreased or followed fluctuant reduction with increasing PS doses, whereas the trichloromethane, trichloroacetic acid and dichloroacetonitrile persistently increased, which was inferred to be related to the variation of AOM. This study suggests that UV/PS might be a potential pretreatment process to assist coagulation on the removal of algae.
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http://dx.doi.org/10.1016/j.jhazmat.2016.10.017DOI Listing
January 2017

Perovskite-Like Polar Lanthanide Formate Frameworks of [NHNH][Ln(HCOO)] (Ln = Tb-Lu and Y): Synthesis, Structures, Magnetism, and Anisotropic Thermal Expansion.

Inorg Chem 2016 Oct 1;55(20):10075-10082. Epub 2016 Jul 1.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, P. R. China.

A series of isostructural hydrazinium lanthanide (Ln) formate framework compounds of [NHNH][Ln(HCOO)] for Ln ions from Tb to Lu and Y have been successfully prepared by utilizing NHNH. The compounds crystallize in orthorhombic polar space group Pca2, with cell parameters at 180 K of a = 18.2526(7)-18.1048(5) Å, b = 6.5815(2)-6.5261(2) Å, c = 7.6362(3)-7.5044(2) Å, and V = 917.33(6)-886.67(4) Å, showing the effect of lanthanide contraction. The compounds possess polar perovskite-like structures incorporating the hydrazinium cations in the cavities of the NaCl-like framework, in which the Ln ions in a bicapped trigonal prism are connected by anti-anti and syn-anti formate groups. The N-H···O hydrogen-bonding interactions are between the hydrazinium cations and the anionic framework. One anti-anti formate group is frustrated by the competitive N-H···O hydrogen-bonding interactions. It thus twists or flips upon warming, resulting in large anisotropic thermal expansion and negative thermal expansion below 180 K. A comparison with the transition metal and magnesium analogues revealed that the structural compactness, tighter binding of the hydrazinium cation by the framework, and symmetrically better match between the framework and ammonium cation for Ln compounds could inhibit the occurrence of phase transition in the series. The IR spectroscopic, thermal, and magnetic properties are investigated.
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http://dx.doi.org/10.1021/acs.inorgchem.6b00952DOI Listing
October 2016

Integrating powdered activated carbon into wastewater tertiary filter for micro-pollutant removal.

J Environ Manage 2016 Jul 12;177:45-52. Epub 2016 Apr 12.

Department of Water Management, Faculty of Civil Engineering and Geoscience, Delft University of Technology, P.O. Box 5048, 2600, GA, Delft, The Netherlands.

Integrating powdered activated carbon (PAC) into wastewater tertiary treatment is a promising technology to reduce organic micro-pollutant (OMP) discharge into the receiving waters. To take advantage of the existing tertiary filter, PAC was pre-embedded inside the filter bed acting as a fixed-bed adsorber. The pre-embedding (i.e. immobilization) of PAC was realized by direct dosing a PAC solution on the filter top, which was then promoted to penetrate into the filter media by a down-flow of tap water. In order to examine the effectiveness of this PAC pre-embedded filter towards OMP removal, batch adsorption tests, representing PAC contact reactor (with the same PAC mass-to-treated water volume ratio as in the PAC pre-embedded filter) were performed as references. Moreover, as a conventional dosing option, PAC was dosed continuously with the filter influent (i.e. the wastewater secondary effluent with the investigated OMPs). Comparative results confirmed a higher OMP removal efficiency associated with the PAC pre-embedded filter, as compared to the batch system with a practical PAC residence time. Furthermore, over a filtration period of 10 h (approximating a realistic filtration cycle for tertiary filters), the continuous dosing approach resulted in less OMP removal. Therefore, it was concluded that the pre-embedding approach can be preferentially considered when integrating PAC into the wastewater tertiary treatment for OMP elimination.
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http://dx.doi.org/10.1016/j.jenvman.2016.04.003DOI Listing
July 2016

A Variety of Phase-Transition Behaviors in a Niccolite Series of [NH3 (CH2 )4 NH3 ][M(HCOO)3 ]2.

Chemistry 2016 Apr 15;22(18):6199-203. Epub 2016 Mar 15.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.

A niccolite series of [bnH2 (2+) ][M(HCOO)3 ]2 (bnH2 (2+) =1,4-butyldiammonium) shows four kinds of metal-dependent phase transitions, from high temperature para-electric phases to low-temperature ferro-, antiferro-, glass-like, and para-electric phases. The conformational flexibility of bnH2 (2+) and the different size, mass, and bonding character of the metal ion lead to various disorder-order transitions of bnH2 (2+) in the lattice and relevant framework modulations, thus different phase transitions and dielectric responses. The magnetic members display a coexistence or combination of electric and magnetic orderings in the low-temperature region.
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http://dx.doi.org/10.1002/chem.201600689DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5069585PMC
April 2016

Influence of activated carbon preloading by EfOM fractions from treated wastewater on adsorption of pharmaceutically active compounds.

Chemosphere 2016 May 15;150:49-56. Epub 2016 Feb 15.

Faculty of Civil Engineering and Geoscience, Delft University of Technology, P.O. Box 5048, 2600GA Delft, The Netherlands.

In this study, the preloading effects of different fractions of wastewater effluent organic matter (EfOM) on the adsorption of trace-level pharmaceutically active compounds (PhACs) onto granular activated carbon (GAC) were investigated. A nanofiltration (NF) membrane was employed to separate the EfOM by size, and two GACs with distinct pore structures were chosen for comparison. The results showed that preloading with EfOM substantially decreased PhAC uptake of the GACs; however, comparable PhAC adsorption capacities were achieved on GACs preloaded by feed EfOM and the NF-permeating EfOM. This indicates that: (1) the NF-rejected, larger EfOM molecules with an expectation to block the PhAC adsorption pores exerted little impact on the adsorbability of PhACs; (2) the smaller EfOM molecules present in the NF permeate contributed mainly to the decrease in PhAC uptake, mostly due to site competition. Of the two examined GACs, the wide pore-size-distributed GAC was found to be more susceptible to EfOM preloading than the microporous GAC. Furthermore, among the fourteen investigated PhACs, the negatively charged hydrophilic PhACs were generally subjected to a greater EfOM preloading impact.
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http://dx.doi.org/10.1016/j.chemosphere.2016.01.121DOI Listing
May 2016

Temperature-Induced Irreversible Phase Transition From Perovskite to Diamond But Pressure-Driven Back-Transition in an Ammonium Copper Formate.

Angew Chem Int Ed Engl 2016 Feb 28;55(6):2097-100. Epub 2015 Dec 28.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.

The compound [CH3 CH2 NH3][Cu(HCOO)3] undergoes a phase transition at 357 K, from a perovskite to a diamond structure, by heating. The backward transition can be driven by pressure at room temperature but not cooling under ambient or lower pressure. The rearrangement of one long copper-formate bond, the switch of bridging-chelating mode of the formate, the alternation of N-H⋅⋅⋅O H-bonds, and the flipping of ethylammonium are involved in the transition. The strong N-H⋅⋅⋅O H-bonding probably locks the metastable diamond phase. The two phases display magnetic and electric orderings of different characters.
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http://dx.doi.org/10.1002/anie.201510024DOI Listing
February 2016

An A-site mixed-ammonium solid solution perovskite series of [(NH2 NH3 )x (CH3 NH3 )1-x ][Mn(HCOO)3 ] (x=1.00-0.67).

Angew Chem Int Ed Engl 2015 Sep 4;54(38):11093-6. Epub 2015 Aug 4.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China).

The A-site mixed-ammonium solid solutions of metal-organic perovskites [(NH2 NH3 )x (CH3 NH3 )1-x ][Mn(HCOO)3 ] (x=1.00-0.67) exhibit para- to ferroelectric diffuse phase transitions with lowered transition temperatures from x=1.00 to 0.67. These properties are due to the decreased framework distortion and polarization in their low temperature ferroelectric phases caused by the increased CH3 NH3 (+) concentration.
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http://dx.doi.org/10.1002/anie.201504396DOI Listing
September 2015

Reuse of spent granular activated carbon for organic micro-pollutant removal from treated wastewater.

J Environ Manage 2015 Sep 18;160:98-104. Epub 2015 Jun 18.

Faculty of Civil Engineering and Geoscience, Delft University of Technology, P.O. Box 5048, 2600GA, Delft, The Netherlands.

Spent granular activated carbons (sGACs) for drinking water treatments were reused via pulverizing as low-cost adsorbents for micro-pollutant adsorption from a secondary treated wastewater effluent. The changes of physicochemical characteristics of the spent carbons in relation to the fresh carbons were determined and were correlated to the molecular properties of the respective GAC influents (i.e. a surface water and a groundwater). Pore size distribution analysis showed that the carbon pore volume decreased over a wider size range due to preloading by surface water, which contains a broader molecular weight distribution of organic matter in contrast to the groundwater. However, there was still considerable capacity available on the pulverized sGACs for atrazine adsorption in demineralized water and secondary effluent, and this was particularly the case for the groundwater spent GAC. However, as compared to the fresh counterparts, the decreased surface area and the induced surface acidic groups on the pulverized sGACs contributed both to the lower uptake and the more impeded adsorption kinetic of atrazine in the demineralized water. Nonetheless, the pulverized sGACs, especially the one preloaded by surface water, was less susceptible to adsorption competition in the secondary effluent, due to its negatively charged surface which can repulse the accessibility of the co-present organic matter. This suggests the reusability of the drinking water spent GACs for micro-pollutant adsorption in the treated wastewater.
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http://dx.doi.org/10.1016/j.jenvman.2015.06.011DOI Listing
September 2015

A 36-fold multiple unit cell and switchable anisotropic dielectric responses in an ammonium magnesium formate framework.

Angew Chem Int Ed Engl 2015 Feb 13;54(8):2534-7. Epub 2015 Jan 13.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China).

An ammonium Mg formate framework, prepared by using di-protonated 1,3-propanediamine (pnH2(2+)), has a rare three-dimensional binodal (4(12)⋅6(3))(4(9)⋅6(6))3 Mg-formate framework with elongated cavities accommodating pnH2(2+)⋅⋅⋅H2O⋅⋅⋅pnH2(2+) assemblies. It displays a para-electric to antiferroelectric phase transition at 275 K, with a 36-fold multiple unit cell from the high-temperature cell of 1703 Å(3) to the low-temperature one of 60,980 Å(3). The change results from the disorder-order transition of the pnH2(2+) cations and H2O molecules. The motions of these components freeze in a stepwise fashion on going from the high-temperature disorder state to the low-temperature ordered state, triggering the switch from high to low dielectric constants, and the spatial limitation of such motions contributes the strong dielectric anisotropy.
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http://dx.doi.org/10.1002/anie.201411005DOI Listing
February 2015

A copper-formate framework showing a simple to helical antiferroelectric transition with prominent dielectric anomalies and anisotropic thermal expansion, and antiferromagnetism.

Chemistry 2014 Nov 9;20(48):15872-83. Epub 2014 Oct 9.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials, Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China), Fax: 86-10-62751708.

We present here the compound [NH4][Cu(HCOO)3], a new member of the [NH4][M(HCOO)3] family. The Jahn-Teller Cu(2+) ion leads to a distorted 4(9)⋅6(6) chiral Cu-formate framework. In the low-temperature (LT) orthorhombic phase, the Cu(2+) is in an elongated octahedron, and the NH₄⁺ ions in the framework channel are off the channel axis. From 94 to 350 K the NH₄⁺ ion gradually approaches the channel axis and the related modulation of the framework and the hydrogen-bond system occurs. The LT phase is simple antiferroelectric (AFE). The material becomes hexagonal above 355 K. In the high-temperature (HT) phase, the Cu(2+) octahedron is compressed, and the NH₄⁺ ions are arranged helically along the channel axis. Therefore, the phase transition is one from LT simple AFE to HT helical AFE. The temperature-dependent structure evolution is accompanied by significant thermal and dielectric anomalies and anisotropic thermal expansion, due to the different status of the NH₄⁺ ions and the framework modulations, and the structure-property relationship was established based on the extensive variable-temperature single-crystal structures. The material showed long range ordering of antiferromagnetism (AFM), with low dimensional character and a Néel temperature of 2.9 K. Therefore, within the material AFE and AFM orderings coexist in the low-temperature region.
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http://dx.doi.org/10.1002/chem.201403466DOI Listing
November 2014

[(C2H5)4N][U2O4(HCOO)5], an ammonium uranyl formate framework showing para- to ferro-electric transition: synthesis, structures, and properties.

Inorg Chem 2014 Aug 29;53(16):8708-16. Epub 2014 Jul 29.

Beijing National Laboratory for Molecular Sciences, Fundamental Science Laboratory on Radiochemistry & Radiation Chemistry, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.

We report an ammonium uranyl formate framework of formula [(C2H5)4N][U2O4(HCOO)5], prepared by using components of tetraethylammonium, uranyl, and formate. The compound possesses a layered structure of anionic uranyl-formate wavy sheets and intercalated (C2H5)4N(+) cations. The sheet consists of pentagonal bipyramidal uranyl cations connected by equatorial anti-anti and anti-syn HCOO(-) bridges, and it has a topology of 3(3)·4(3)·5(4) made of edge-sharing square and triangle grids. The high-temperature (HT) phase belongs to the chiral but nonpolar tetragonal space group P42(1)m. In the structure, one HCOO(-) is 2-fold disordered, showing a flip motion between the two anti-syn orientations. On cooling, this flip motion slowed and finally froze, leading to a phase transition at ∼200 K. The low-temperature (LT) structure is monoclinic and polar in space group P2(1); the cations shift, and the layers slide. Especially, the concerted and net shifts of the ammonium cations toward the -b direction, with respect to the anionic sheets, result in an estimated spontaneous polarization of 0.86 μC cm(-2) in LT. The phase transition is thus para- to ferro-electric, in Aizu notation 42mF2, accompanied by significant, anisotropic dielectric anomalies, with a quite significant thermal hysteresis. Variable-temperature luminescent spectroscopy and differential scanning calorimetry confirmed the transition and provided further information. The structure-property relationship is established.
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http://dx.doi.org/10.1021/ic501336xDOI Listing
August 2014

Uniaxial movements of a metal-cyanide framework switched by weak interactions through dehydration and rehydration.

Chemistry 2014 Jul 6;20(27):8269-73. Epub 2014 Jun 6.

Ordered Matter Science Research Center, Southeast University, Jiangning District, Nanjing 211189 (P. R. China), Fax: (+86) 25-5209-0626.

A metal-cyanide framework undergoes a dehydration-rehydration triggered reversible single-crystal-to-single-crystal transformation. The resulting accordion-like contraction-expansion corresponds to a size change along the c axis as much as 24 %. This anisotropic response arises from the cooperativity among the water molecules, K ions, and CN groups between the unique two-dimensional bimetallic layers through weak interactions of hydrogen bonds and electrostatic (ionic) interactions. The key role of the water molecules in the dehydration-rehydration process is revealed by solid-state (1)H NMR spectroscopy and dielectric measurements.
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http://dx.doi.org/10.1002/chem.201402892DOI Listing
July 2014

Kinetics of cell inactivation, toxin release, and degradation during permanganation of Microcystis aeruginosa.

Environ Sci Technol 2014 17;48(5):2885-92. Epub 2014 Feb 17.

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University , Shanghai City 200092, China.

Potassium permanganate (KMnO4) preoxidation is capable of enhancing cyanobacteria cell removal. However, the impacts of KMnO4 on cell viability and potential toxin release have not been comprehensively characterized. In this study, the impacts of KMnO4 on Microcystis aeruginosa inactivation and on the release and degradation of intracellular microcystin-LR (MC-LR) and other featured organic matter were investigated. KMnO4 oxidation of M. aeruginosa exhibited some kinetic patterns that were different from standard chemical reactions. Results indicated that cell viability loss and MC-LR release both followed two-segment second-order kinetics with turning points of KMnO4 exposure (ct) at cty and ctr, respectively. KMnO4 primarily reacted with dissolved and cell-bound extracellular organic matter (mucilage) and resulted in a minor loss of cell viability and MC-LR release before the ct value reached cty. Thereafter, KMnO4 approached the inner layer of the cell wall and resulted in a rapid decrease of cell viability. Further increase of ct to ctr led to cell lysis and massive release of intracellular MC-LR. The MC-LR release rate was generally much slower than its degradation rate during permanganation. However, MC-LR continued to be released even after total depletion of KMnO4, which led to a great increase in MC-LR concentration in the treated water.
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http://dx.doi.org/10.1021/es405014gDOI Listing
October 2015

Effect of PAC dosage in a pilot-scale PAC-MBR treating micro-polluted surface water.

Bioresour Technol 2014 Feb 22;154:290-6. Epub 2013 Dec 22.

Delft University of Technology, P. O. Box 5048, 2600 GA Delft, The Netherlands.

To address the water scarcity issue and advance the traditional drinking water treatment technique, a powdered activated carbon-amended membrane bioreactor (PAC-MBR) is proposed for micro-polluted surface water treatment. A pilot-scale study was carried out by initially dosing different amounts of PAC into the MBR. Comparative results showed that 2g/L performed the best among 0, 1, 2 and 3g/L PAC-MBR regarding organic matter and ammonia removal as well as membrane flux sustainability. 1g/L PAC-MBR exhibited a marginal improvement in pollutant removal compared to the non-PAC system. The accumulation of organic matter in the bulk mixture of 3g/L PAC-MBR led to poorer organic removal and severer membrane fouling. Molecular weight distribution of the bulk liquid in 2g/L PAC-MBR revealed the synergistic effects of PAC adsorption/biodegradation and membrane rejection on organic matter removal. Additionally, a lower amount of soluble extracellular polymer substances in the bulk can be secured in 21 days operation.
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http://dx.doi.org/10.1016/j.biortech.2013.12.075DOI Listing
February 2014

Phase transitions, prominent dielectric anomalies, and negative thermal expansion in three high thermally stable ammonium magnesium-formate frameworks.

Chemistry 2014 Jan 16;20(4):1146-58. Epub 2013 Dec 16.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China), Fax: (+86) 10-62751708.

We present three Mg-formate frameworks, incorporating three different ammoniums: [NH4][Mg(HCOO)3] (1), [CH3CH2NH3][Mg(HCOO)3] (2) and [NH3(CH2)4NH3][Mg2(HCOO)6] (3). They display structural phase transitions accompanied by prominent dielectric anomalies and anisotropic and negative thermal expansion. The temperature-dependent structures, covering the whole temperature region in which the phase transitions occur, reveal detailed structural changes, and structure-property relationships are established. Compound 1 is a chiral Mg-formate framework with the NH4(+) cations located in the channels. Above 255 K, the NH4(+) cation vibrates quickly between two positions of shallow energy minima. Below 255 K, the cations undergo two steps of freezing of their vibrations, caused by the different inner profiles of the channels, producing non-compensated antipolarization. These lead to significant negative thermal expansion and a relaxor-like dielectric response. In perovskite 2, the orthorhombic phase below 374 K possesses ordered CH3CH2NH3(+) cations in the cubic cavities of the Mg-formate framework. Above 374 K, the structure becomes trigonal, with trigonally disordered cations, and above 426 K, another phase transition occurs and the cation changes to a two-fold disordered state. The two transitions are accompanied by prominent dielectric anomalies and negative and positive thermal expansion, contributing to the large regulation of the framework coupled the order-disorder transition of CH3CH2NH3(+). For niccolite 3, the gradually enhanced flipping movement of the middle ethylene of [NH3(CH2)4NH3](2+) in the elongated framework cavity finally leads to the phase transition with a critical temperature of 412 K, and the trigonally disordered cations and relevant framework change, providing the basis for the very strong dielectric dispersion, high dielectric constant (comparable to inorganic oxides), and large negative thermal expansion. The spontaneous polarizations for the low-temperature polar phases are 1.15, 3.43 and 1.51 μC cm(-2) for 1, 2 and 3, respectively, as estimated by the shifts of the cations related to the anionic frameworks. Thermal and variable-temperature powder X-ray diffraction studies confirm the phase transitions, and the materials are all found to be thermally stable up to 470 K.
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http://dx.doi.org/10.1002/chem.201303425DOI Listing
January 2014

Tight ceramic UF membrane as RO pre-treatment: the role of electrostatic interactions on phosphate rejection.

Water Res 2014 Jan 14;48:498-507. Epub 2013 Oct 14.

Department of Sanitary Engineering, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, 2600 GA Delft, The Netherlands. Electronic address:

Phosphate limitation has been reported as an effective approach to inhibit biofouling in reverse osmosis (RO) systems for water purification. The rejection of dissolved phosphate by negatively charged TiO2 tight ultrafiltration (UF) membranes (1 kDa and 3 kDa) was observed. These membranes can potentially be adopted as an effective process for RO pre-treatment in order to constrain biofouling by phosphate limitation. This paper focuses on electrostatic interactions during tight UF filtration. Despite the larger pore size, the 3 kDa ceramic membrane exhibited greater phosphate rejection than the 1 kDa membrane, because the 3 kDa membrane has a greater negative surface charge and thus greater electrostatic repulsion against phosphate. The increase of pH from 6 to 8.5 led to a substantial increase in phosphate rejection by both membranes due to increased electrostatic repulsion. At pH 8.5, the maximum phosphate rejections achieved by the 1 kDa and 3 kDa membrane were 75% and 86%, respectively. A Debye ratio (ratio of the Debye length to the pore radius) is introduced in order to evaluate double layer overlapping in tight UF membranes. Threshold Debye ratios were determined as 2 and 1 for the 1 kDa and 3 kDa membranes, respectively. A Debye ratio below the threshold Debye ratio leads to dramatically decreased phosphate rejection by tight UF membranes. The phosphate rejection by the tight UF, in combination with chemical phosphate removal by coagulation, might accomplish phosphate-limited conditions for biological growth and thus prevent biofouling in the RO systems.
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http://dx.doi.org/10.1016/j.watres.2013.10.008DOI Listing
January 2014

A new series of chiral metal formate frameworks of [HONH3][M(II)(HCOO)3] (M = Mn, Co, Ni, Zn, and Mg): synthesis, structures, and properties.

Inorg Chem 2012 Dec 5;51(24):13363-72. Epub 2012 Dec 5.

Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China.

We report the synthesis, crystal structures, IR, and thermal, dielectric, and magnetic properties of a new series of ammonium metal formate frameworks of [HONH(3)][M(II)(HCOO)(3)] for M = Mn, Co, Ni, Zn, and Mg. They are isostructural and crystallize in the nonpolar chiral orthorhombic space group P2(1)2(1)2(1), a = 7.8121(2)-7.6225(2) Å, b = 7.9612(3)-7.7385(2) Å, c = 13.1728(7)-12.7280(4) Å, and V = 819.27(6)-754.95(4) Å(3). The structures possess anionic metal formate frameworks of 4(9)·6(6) topology, in which the octahedral metal centers are connected by the anti-anti formate ligands and the hydroxylammonium is located orderly in the channels, forming strong O/N-H···O(formate) hydrogen bonds with the framework. HONH(3)(+) with only two non-H atoms favors the formation of the dense chiral 4(9)·6(6) frameworks, instead of the less dense 4(12)·6(3) perovskite frameworks for other monoammoniums of two to four non-H atoms because of its small size and its ability to form strong hydrogen bonding. However, the larger size of HONH(3)(+) compared to NH(4)(+) resulted in simple dielectric properties and no phase transitions. The three magnetic members (Mn, Co, and Ni) display antiferromagnetic long-range ordering of spin canting, at Néel temperatures of 8.8 K (Mn), 10.9 K (Co), and 30.5 K (Ni), respectively, and small spontaneous magnetizations for the Mn and Ni members but large magnetization for the Co member. Thermal and IR spectroscopic properties are also reported.
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http://dx.doi.org/10.1021/ic302129mDOI Listing
December 2012
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