Dyes wastewater treatment by reduction-oxidation process in an electrochemical reactor packed with natural manganese mineral

A novel technology which combined electrochemical process catalyzed by manganese mineral with electro-assisted coagulation process was proposed in this study. The mineralization of organic pollutant from simulated dye wastewater containing an azo dye Acid Red B（ARB） was experimentally investigated using this method. It was found that the manganese mineral could catalyze the electrochemical process dramatically. The TOC removal percentage of electrochemical treatment catalyzed by manganese mineral was 43.6% while the TOC removal percentage of the process using the manganese mineral alone and using the electrolysis alone were 9.3% and 20.8%, respectively. Moreover, it was found that combined electroxidation with electro-assisted coagulation process could more effectively eliminate ARB. After a period of 180 min electrooxidation and 300 min electroreduction, almost 66.9% of TOC was removed, and the dissolved Mn^2＋. could be effectivly removed. The effects of the order of oxidation and reduction, the proper ratio electrooxidation/reduction time, and current density on the removal efficiency were investigated in detail. In addition, a proposed mechanism of manganese-mineral-catalyzed electrooxidation-reduction process was discussed in this paper.

Treatment of mine water high in Fe and Mn by modified manganese sand

The iron and manganese absorption properties of several filter media were studied. Four plain filter media and six surface-modified media were examined. The surface modification was performed using potassium permanganate as a surface treatment. The surface-modified manganese sand was found to be most efficient at removing iron and manganese from water. The metal concentrations in filtered effluent were between 0.01 and 0.04 mg/L, which is far lower than the standard for recycle water. A concen-tration of 5% KMnO4 was found to be most effective as surface modifier. The surface of the manganese sand modified by 5% KMnO4 was examined and found to be covered with a dense membrane of some compound. The membrane had the advantages of uniform texture, large surface area and physical and chemical stability. It was effective at removing iron and manganese from mine water.

Manganese peroxidase production from cassava residue by Phanerochaete chrysosporium in solid state fermentation and its decolorization of indigo carmine

Bioconversion of lignocellulosic wastes to higher value products through fungal fermentation has economic and ecological benefits. In this study, to develop an effective strategy for production of manganese peroxidase(Mn P)from cassava residue by Phanerochaete chrysosporium in solid state fermentation, the stimulators of Mn P production were screened and their concentrations were optimized by one-at-a-time experiment and Box–Behnken design. The maximum Mn P activity of 186.38 nkat·g-1dry mass of the sample was achieved after 6 days of fermentation with the supplement of 79.5 mmol·L-1·kg-1acetic acid, 3.21 ml·kg-1soybean oil, and 28.5 g·kg-1alkaline lignin, indicating that cassava residue is a promising substrate for Mn P production in solid state fermentation. Meanwhile, in vitro decolorization of indigo carmine by the crude Mn P was also carried out, attaining the ratio of 90.18% after 6 h of incubation. An oxidative mechanism of indigo carmine decolorization by Mn P was proposed based on the analysis of intermediate metabolites with ultra-high performance liquid chromatography and gas chromatography tandem mass spectrometry. Using the crude Mn P produced from cassava residue for indigo carmine decolorization gives an effective approach to treat dyeing effluents.

Synthesis and Crystal Structure of a Salicylaldehyde Ethylene Diamine Schiff Base Manganese (Ⅲ) Complex

The title compound, [Mn(salen)(salicyl)]?.5H2O ( H2salen = N, N?ethylenebis- (salicylideneaminato), Hsalicyl = salicylaldehyde), has been obtained from the reaction system containing (o-HOC6H4CH=NCH2)2, o-HOC6H4CHO and Mn(ClO4)2?H2O in EtOH solvent and structurally characterized. It crystallizes in the monoclinic, space group P21/c with a = 13.0548(4), b = 13.9254(4), c = 11.6630(1) ? b = 105.199(2)? V = 2046.09(9) ?, Z = 4, C23H22MnN2O5.5, Mr = 469.37, Dc = 1.524 g/cm3, F(000) = 972, m = 0.687mm-1 . R = 0.0630 and wR = 0.1142 for 1901 observed reflections with I >2(I). The Mn(Ⅲ) is coordinated by N(1), N(2), O(1) and O(2) of the Schiff base ligand and phenolate O atom of salicylaldehyde with O(3)Mn distance of 2.050(4) , forming a relatively rare five-coordinate square-pyramidal structure.

Effects of Exogenous Manganese (Mn) on Mineral Elements, Polyamines and Antioxidants in Apple Rootstock Malus robusta Rehd.

Manganese(Mn)is one of the essential microelements in all organisms.However,high level of Mn is deleterious to plants.In this study,the effects of exogenous manganese application on mineral element,polyamine(PA)and antioxidant accumulation,as well as polyamine metabolic and antioxidant enzyme activities,were investigated in Malus robusta Rehd.,a widely grown apple rootstock.High level of Mn treatments decreased endogenous Mg,Na,K and Ca contents,but increased Zn content,in a Mn-concentration-dependent manner.Polyamine metabolic assays revealed that,except the content of perchloric acid insoluble bound(PIS-bound)spermine,which increased significantly,the contents of putrescine(Put),spermidine(Spd)and spermine(Spm)all decreased progressively,accompanied with the decreased activities of arginine decarboxylase(ADC,EC 4.1.1.19)and ornithine decarboxylase(ODC,EC 4.1.1.17),and the increased activities of diamine oxidase(DAO,EC 1.4.3.6)and polyamine oxidase(PAO,EC 1.5.3.3).Further antioxidant capacity analyses demonstrated that contents of anthocyanin,non-protein thiols(NPT)and soluble sugar,and the activities of guaiacol peroxidase(POD,EC 1.11.1.7),catalase(CAT,EC 1.11.1.6)and superoxide dismutase(SOD,EC 1.15.1.1),also increased upon different concentrations of Mn treatments.Our results suggest that endogenous ion homeostasis is affected by high level of Mn application,and polyamine and antioxidant metabolism is involved in the responses of M.robusta Rehd.plants to high level of Mn stress.

Ore petrography of low-grade siliceous manganese ores from the Bonai-Keonjhar belt, Orissa, India: The influence of mineral-fabric on their beneficiation

Low grade siliceous manganese ores from the iron ore group of the Bonai-Keonjhar belt, Orissa, India are found mostly in shear zones. The ore characteristics of siliceous manganese ore samples from three differ- ent mines, viz. the Shankar (Barbil OMC lease hold area), the Sone-Patuli (Patmunda, OMM lease hold area), and the Musaghar (Roida, OMDC lease hold area), were studied. These siliceous manganese ores are of three types, respectively: (i) spongy-granular; (ii) massive-mosaic; and (iii) hard-mylonitized. The spongy-gran- ular type contains granular, saccharoidal quartz and the major manganese mineral present is pyrolusite. The second type contains well crystallized quartz and cryptomelane, while the third has cherty, fine grained quartz (mylonite) along with romanechite. All three ores were subjected to physical beneficiation under similar conditions. Both gravity and magnetic separation techniques were employed. The mineral-fabric of the ores has been correlated to the extent of their beneficiation using these physical techniques. Of these three ores only the spongy-granular type responded well to upgrading. The feed with 22% Mn content could be upgraded to 44% with a 28% yield and a 49% recovery. The good response to beneficiation of the spongy- granular sample could be due to the large euhedral crystals of pyrolusite and the friable nature of the sac- charoidal quartz. This study reveals the influence of mineral-fabric on beneficiation of low grade ore, siliceous Mn ore in particular.

Heterointerface Engineering-Induced Oxygen Defects for the Manganese Dissolution Inhibition in Aqueous Zinc Ion Batteries

Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy.

Facile synthesis of Cu-doped manganese oxide octahedral molecular sieve for the efficient degradation of sulfamethoxazole via peroxymonosulfate activation

Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive species,including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radical(·O_(2)^(-)),and singlet oxygen(1O_(2)),which can induce the degradation of organic contaminants.In this work,we synthesized a variety of M-OMS-2 nanorods(M=Co,Ni,Cu,Fe)by doping Co^(2+),Ni^(2+),Cu^(2+),or Fe^(3+)into manganese oxide oc-tahedral molecular sieve(OMS-2)to efficiently remove sulfamethoxazole(SMX)via PMS activation.The catalytic performance of M-OMS-2 in SMX elimination via PMS activation was assessed.The nanorods obtained in decreasing order of SMX removal rate were Cu-OMS-2(96.40%),Co-OMS-2(88.00%),Ni-OMS-2(87.20%),Fe-OMS-2(35.00%),and OMS-2(33.50%).Then,the kinetics and struc-ture-activity relationship of the M-OMS-2 nanorods during the elimination of SMX were investigated.The feasible mechanism underly-ing SMX degradation by the Cu-OMS-2/PMS system was further investigated with a quenching experiment,high-resolution mass spec-troscopy,and electron paramagnetic resonance.Results showed that SMX degradation efficiency was enhanced in seawater and tap water,demonstrating the potential application of Cu-OMS-2/PMS system in sewage treatment.

Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage

Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties.

Controllable synthesis of novel nanoporous manganese oxide catalysts for the direct synthesis of imines from alcohols and amines

A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by controlling the calcination conditions,which were employed as the efficient catalysts for the oxidative coupling of alcohols with amines to imines.The chemical and structural properties of the manganese oxides were characterized by the methods of thermogravimetry analysis and heat flow(TG-DSC),X-ray diffraction(XRD),nitrogen sorption,scanning electron microscope(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),H2 temperature-programmed reduction(H2-TPR),and inductively coupled plasma optical emission spectrometry(ICP-OES)techniques.The structures of different manganese oxides were confirmed by characterization.The M-350(AMO)presented the maximum surface area,amorphous nature,the lowest reduction temperature,the higher(Mn3++Mn4+)/Mn2+ratio,and the higher adsorbed oxygen species compared to other samples.Among the catalysts,M-350 showed the best catalytic performance using air as an oxidant,and the conversion of benzyl alcohol(BA)and the selectivity of N-benzylideneaniline(NBA)reached as high as 100%and 97.1%respectively at the lower reaction temperature(80°C)for 1 h.M-350 had also the highest TOF value(0.0100 mmol·mg-1·h-1)compared to the other manganese oxide catalysts.The catalyst was reusable and gave 95.8%conversion after 5 reuse tests,the XRD pattern of the reactivated M-350 did not show any obvious change.Lattice oxygen mobility and(Mn3++Mn4+)/Mn2+ratio were found to play the important roles in the catalytic activity of aerobic reactions.

Reversing the negative effects of co-inhaled manganese and iron on dopamine levels and prolactin production in the rat hypothalamus-pituitary axis

BACKGROUND： Manganese （Mn） and iron （Fe） are the primary elements of welding rods. Mn has been shown to increase prolactin （PRL） production by decreasing dopamine （DA） levels in the hypothalamus. However, Fe increases DA levels and decreases PRL levels. The toxic mechanism of Mn and Fe co-inhalation-induced regulation of the hypothalamic-hypophyseal-pituitary axis remains unclear. OBJECTIVE： To evaluate the effects of co-inhaled Mn and Fe on hypothalamic DA levels and pituitary PRL production, to investigate whether these changes are reversible, and to determine the role of co-inhaled Mn and Fe. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment based on inhalation toxicity via whole-body exposure was performed. Hypothalamic DA levels, serum PRL, and PRL and PiN mRNA levels were analyzed at the Institute of Environmental and Occupational Medicine, Inje University, Busan, Korea, from August 2007 to May 2009. MATERIALS： MnSO4 and FeSO4 were purchased from Sigma-Aldrich, St. Louis, MO, USA. High-performance liquid chromatography （HPLC） using an electrochemical detector （ECD） was purchased from Waters Corporation, Milford, MA, USA. mRNA Capture Kit and reverse transcription-polymerase chain reaction （RT-PCR） kit were obtained from Roche Molecular Biochemicals, Mannheim, Germany and Perkin-Elmer, Wellesley, MA, USA, respectively. Rat PRL enzyme-linked immunosorbent assay kit was purchased from Biocode Hycel, Liege, Belgium. METHODS： Eighty 15-week-old, male, Fischer 344 rats were assigned to two groups： one group treated with Mn and Fe and a control group. Each group was sub-divided into four groups on the basis of treatment period （0- and 13-week treated groups with both chemicals） and recovery periods （4- and 13-week recovery groups following 13-week exposure to both chemicals）. The treatment condition was 6 hours per day, 5 days per week, for the entire body. Mn and Fe co-inhalation concentrations were 1.5 mg/m3 and 3.0 mg/m3, respectively. MAIN OUTCOME MEASURES： Hypothalamic DA levels were measured using HPLC-ECD analysis mRNA levels of PRL and Pit-1 were analyzed by Northern blot hybridization and RT-PCR, respectively. Serum PRL levels were measured by enzyme-linked immunosorbent assay. RESULTS： HPLC-ECD analysis revealed that following 13-week co-inhalation of Mn and Fe, hypothalamic DA levels significantly deceased, whereas pituitary PRL mRNA, Pit-1 mRNA, and serum PRL levels significantly increased. At 4 weeks of recovery, DA level in the hypothalamic tissue was significantly increased, and PRL and Pit-1 mRNA levels in the pituitary were significantly decreased. After 13 weeks of recovery, DA and PRL levels recovered to normal. The changing pattern of serum PRL levels was in accordance with pituitary PRL mRNA levels. CONCLUSION： Subchronic co-inhalation of Mn and Fe significantly decreased hypothalamic DA levels, but induced pituitary PRL production, both of which were mediated by Pit-1. These results suggested that Mn dominates over Fe in terms of hypothalamic DA levels and pituitary PRL production, and these effects are reversible in a subchronic inhalation condition. Therefore, changes in hypothalamic DA levels and serum PRL production could be used as biomarkers for welders, who are exposed to Mn and Fe.

Synthesis and Crystal Structure of o-Vanillin Ethylene Diamine Schiff Base One AceticAcid Manganese(Ⅱ) Monohydrate

The title compound of o-vanillin ethylene diamine Schiff base monoacetic acid manganese(Ⅱ) monohydrate, Mn((CH3 OC6 H3 OCHNC2H4NCHC6H3OO-CH3) (H2O) (CH3COOH). CH3OH. 2H2O, was synthesized and its crystal structurewas determined by X-ray diffraction methed. Crystal data are: Mr = 527. 43, monoclinic system, space group C2/c, Z= 8 F a= 17. 720(4), b= 12. 584(3), c= 22. 648(5)A, β= 112. 61 (3)°； V=4662(4) A, Dx=1. 503 g/cm3, μ=5. 99 cm-1, F(000) =2216. The final agreement factors are R= 0. 053 and Rw= 0. 056 for 2208 unique refiections (I>3σ(I) )- The manganese(Ⅱ) is coordinated to N(1), N (2), O(2) ) O(3) of Schiff base ligand, O atom of water and O(11) of acetic acid. They formed adistorted octahedral structure. Each asymmetry contains one solvent methanol moleculeand two solvent water molecules.

Manganese toxicity in the central nervous system: Decreeing of catecholamine in rat’s brains

Manganese is an essential metal in human that functions in many enzymes. In contrast excessive exposure to Mn results in neurotoxicity. Accumulation of manganese damages central nervous system and causes Parkinson disease like syndrome called manganism. Mn neurotoxicity has been suggested to involve an imbalance in catecholamine neurotransmitters. It hypothesized that Mn can obstruct catecholamine synthesis pathway by inhibition of Tyrosine hydroxylase. Previous studies demonstrated that chronic and acute dose of Mn has different possible effects on catecholamine synthesis. It’s assumed that an acute dose of manganese can kill dopaminergic cells. Therefore, we focused the effect of Mn in catecholamine concentration on the rat’s brain by MnCl2 injection intraperitoneally and analyzed their brains after the time interval. This study used different acute doses in short time courses and different chronic doses at different exposing times to investigate which of them (exposing dose or time) is more important in Mn toxic effect. Measurement of catecholamine concentration performed by fluorescence assay in acidic and oxidant environment.

Passive Remediation of Acid Mine Drainage Using Ball-Milling Modified Indonesian Natural Bentonite: Laboratory Batch and Column Sorption of Manganese

Manganese (Mn) is an essential element for human body. However, elevated concentration of manganese causes severe problem and disease. Acid mine drainage (AMD), wastewater generated due to open-pit mining, commonly contains Mn with exceeded concentration. This study is to investigate the improvement of ball-milling modified Indonesian natural bentonite (INB) for manganese (Mn) removal from AMD and to increase the pH through batch and column sorption test as a passive treatment system approach. The batch sorption test result showed the maximum Mn adsorbed (Qm) on INB from the Langmuir model increased from 4.69 to 17.12 mg/g after milling. The column sorption test result also showed the amount of Mn adsorbed on INB until breakthrough time (qu) and until saturation time (q) increased after milling. The qu increased from 1.27 to 10.06 mg/g, and the q increased from 4.55 to 12.91 mg/g. The mass transfer zone (MTZ) became significantly shorter after milling from 0.22 to 0.07 cm. The Thomas model exhibited the equilibrium uptake of Mn (q0) increased after milling from 3.91 to 13.72 mg/g. In equilibrium condition, both unmilled and milled INB showed the pH increased from ≈3 to 8.

Mineragraphic Study of Manganese Ore Deposits of Kandri, Mansar, Beldongri and Satak Mines, Nagpur District (Maharashtra) Central India

In Nagpur, M.P.-Maharashtra Manganese Belt is exposed which is part of Sausar Belt. In Nagpur, four manganese mines viz Mansar, Kandri, Beldongri and Satak are selected for the ore microscopic study. These mining areas are situated in that part of Central India which are highly deformed and metamorphosed and are characterised by high grade amphibolite facies to low grade greenschist facies. The Precambrian manganese ore deposits of Nagpur are formed by the metasediments of Sausar belt which is rich in manganese sediments. The manganese ores of the study area are co-folded with distinct rock types i.e. “gondites” and predominantly composed of a mixture of braunite, bixbyite, hausmannite, hollandite, jacobsite, vredenburgite, pyrolusite, cryptomelane and psilomelane. The dominant rocks are tirodi migmatitic gneiss, argillaceous and calcareous rock types. This paper discusses the mineralogy of the manganese ores of Kandri, Mansar, Satak and Beldongri. After the careful assessment of mineralogy, texture and paragenesis of the manganese ore of the study area, it has been concluded that the manganese ores of the study area are formed by the multiple processes i.e. metamorphism and supergene enrichment. These supergene enrichments are evidence of colloidal influx. Occurrence of free braunite, free hausmannite and free jacobsite indicates the high grade metamorphism. Pyrolusite, rhodonite, and psilomelane-cryptomelane are formed by supergene enrichment. The presence of lamellar twinning in braunite indicates about shear pressure. In this area the different manganese mineral assemblages and their textures suggest about the occurrence of different metamorphic activity and depositional environment. The texture and paragenesis of manganese ore of the study area are discussed here.

Alteration Processes of Paleoproterozoic Manganese Protores of the North Téra:Mineralogy and Geochemistry(West Africa)

The manganese deposit of North Téra is located in the western side of the Diagorou-Darbani greenstone belt in the Niger Liptako Province(Northeastern part of Man Schield,West African Craton).Manganese mineralization bearing rocks are mainly gondites(a kind of garnet-rich quartzite of the spessartine type)whose borders consist of a high concentration of Mn oxide concretions.The methodological approach implemented consisted of a field study followed by a polarizing microscopic analysis in transmitted and reflected light and a geochimical analysis.North Téra gondites originate from Birimian manganese-rich sediments metamorphism in amphibolite facies.The supergene alteration,more or less important,has developed on the protore of gondites,a saprolitic profile whose setting up conditions were recently described in our previous work.The macroscopic analysis of the manganese deposits samples combined with the metallographic microscopic and geochemical analysis confirms that manganese mineralization originated from weathering processes.The first oxide that forms around the garnets is nsutite,while the mesostasis is invaded by pyrolusite with lenses of lithiophorite destabilizing in favor of pyrolusite.In the botryoidal concretions,the latter forms an alternation with the psilomelane rich in Ba(8,101ppm)in the uppermost levels.The abundance diagram shows that the normalize Rare Earths compared to PAAS derived from a plagioclase-rich quartzitic source.This observation is corroborated by a positive anomaly in Eu.Otherwise,the high levels of transition elements(Ni,V,Co and Cr)highlight the involvement of a basic source.The contents of major elements show a significant leaching,with an increase in those of Mn and Al during the increasing weathering.The CIA and PIA indices move in the same direction towards high values leading to the Al2O3 pole on the Al2O3-CaO*+Na2O-K2O diagram.This indicates an increasing alteration along the profile,according to an alteration path comprising plagioclase-smectite-kaolinite and illite to kaolinite.

Occurrence of Manganese Ore Deposits and Their Mineralogy in Vizianagaram-Visakhapatnam Manganese Ores Belt (Andhra Pradesh) India

The Manganese deposits of Andhra Pradesh are associated with a thick sequence of Precambrian rocks, belonging to Khondalite and Charnockite groups of Dharwar Supergroup that forms part of 2500 to 3000 m.y. old Eastern Ghat complex of India. The study area is the Manganese deposits of Vizianagram-Visakhapatnam Manganese Belt of Andhra Pradesh. The study area lies about 150 km NE of Visakhapatnam between 18°12′N - 18°30′N and 83°20′E - 83°45′E. The mineralization of Manganese ores is confined to different rock types, belonging to both Khondalite and Charnockite groups, where they are dispersed throughout the country rocks as small lenses, pockets, veins and irregular bodies of varying dimensions. Quartz, garnet, clay, limonite and apatite are the common gangue minerals in the Manganese ores. The presence of quartz, garnet and apatite brings down the grade of the ore. Ferruginous laterite and ochre generally work as capping of the Manganese deposits. The various Manganese ore minerals present in these deposits are indentified as 1) Primary minerals-braunite, bixbyite, vredenburgite, jacobsite and hausmannite, 2) secondary minerals-psilomelane, cryptomelane, hollandite, pyrolusite and wad. The primary ore minerals are considered to be syngenetic and regionally metamorphosed while, the associated secondary ore minerals are formed due to alteration of the primary ores.

Differential Regulation of Proteins and a Possible Role for Manganese Superoxide Dismutase in Bioluminescence of Panellus stipticus Revealed by Suppression Subtractive Hybridization

Suppression subtractive hybridization (SSH) was employed to investigate bioluminescence in Panellus stipticus (Bull.) P. Karst. by detecting proteins differentially expressed in bioluminescent and luminescent strains. Comparisons of luminescent and non-luminescent monokaryon cultures of North American strains revealed differences in transcript levels of proteins responsible for post-translational modification (PTM) of enzymes. A similar comparison of a luminescent strain of P. stipticus from North America with a non-luminescent European strain revealed the presence of extracellular manganese superoxide dismutase (MnSOD) in the luminescent form, in addition to proteins involved in PTM. The application of MnSOD-specific inhibitors to luminescent mycelium resulted in the rapid loss of luminescence. The relevance to luminescence of proteins involved in PTM is discussed, together with a possible role for MnSOD that considers the potential for SODs to form stable complexes with catechols revealed in previously published research. In light of the recent discovery that hispidine may be the precursor of fungal luciferin, we consider a hypothetical mechanism for fungal luminescence in which the ο-hydroquinone moiety of a hispidine derivative ligates with the extracellular form of MnSOD producing a semiquinone-radical complex, with the resultant semiquinonato complex potentially reacting with molecular oxygen or other reactive oxygen species to produce sufficiently excited intermediates to emit light on relaxation.

Catagenetic type of manganese ores:REE and isotope(δ^(13)C,δ^(18)O)geochemical features(on the example of the Usa deposit,Russia)

Chemical(REE and major elements)and isotope(δ^(13)C,δ^(18)O)composition of carbonate manganese ores and manganese-bearing carbonates of the Usa deposit(Siberia,Russia)were studied.Received data on the composition of REE exhibit both the distinct negative(Ce/Ce*_(PAAS)<1)and positive(Ce/Ce*_(PAAS)>1)cerium anomalies and the positive Eu-anomaly(Eu/Eu*_(PAAS)>1).Negative Eu-anomalies are not observed.The contents of Mn,Fe,REE,and Ce-anomalies show a positive correlation with each other.Ce-anomalies and the amount of manganese and REE in relation to the carbon isotope composition(δ^(13)C)show a negative relationship and indicate that oxidized carbon of organic matter played an important role in the concentration of manganese and REE in manganese ores.The chemical and isotope composition of examined rocks indicates on secondary formation of Mnores.Two major phases and sources are distinguished in the ore-forming process characterized by diff erent chemical(REE and ore elements)and isotope composition:(i)highgrade manganese ores(with high contents of REE and light carbon isotope composition)and(ii)low-grade manganese ores(with low contents of REE and heavy carbon isotope composition).

Preparation of Manganese Oxide and Its Adsorption Properties

The in-situ oxidation of manganese sulfate solution with H2O_(2),sodium hypochlorite,potassium permanganate and oxygen as oxidants was investigated by means of SEM,EDS,XRD,BET and infrared analysis,and the effects of different oxidants on the morphology,phase composition,surface properties and specific surface area of manganese oxides were investigated.The experimental results show that the diameter of manganese oxide particles prepared with H_(2)O_(2)is the smallest,about 50 nm,and the specific surface area is the largest,63.8764 m^(2)/g.It has the advantages of abundant surface hydroxyl groups,no introduction of other impurities and large adsorption potential.It is most suitable to be used as an oxidant for oxidizing manganese sulfate solution to prepare manganese oxide by in-situ oxidation.Nano manganese oxide prepard by H_(2)O_(2)in-situ oxidation method is used as adsorbent to adsorb cobalt and nickel impurities in manganese sulfate.When the reaction pH is 6,the reaction time is 30min and the amount of adsorbent is 1.0 g,the adsorption rates of cobalt and nickel impurities in 100ml manganese sulfate solution are 97.59%and 97.67%,respectively.The residual amounts of cobalt and nickel meet the industrial process standard of first-class products(Co,Ni w/%≤0.005)of high-purity manganese sulfate(Hg/t4823-2015)for batteries.The study plays a guiding role in the preparation and regulation of manganese oxide,and provides a new method with high efficiency,purity and adsorbent availability for the preparation of high-purity manganese sulfate solution.