ICP－AES光谱法同时测定团体废物浸出液中的多种金属元素

采用翻转振荡方式以水为浸提剂浸提钢渣、尾矿渣、铬渣、铅渣、粉煤灰和电镀污泥试样，过滤后的浸提液经ＤＤＴＣ／ＣＣｌ４体系萃取富集后，用ＩＣＰ－ＡＥＳ法同时测定了Ｃｕ、Ｐｂ、Ｚｎ、Ｃｄ、Ｎｉ、Ｆｅ、Ｍｎ、Ｃｏ和Ｖ等多种金属元素．方法具有较好的精密度和准确度，宜于推广应用。

Effects of Ca^(2+)concentrations on accumulations of mineral elements in the components of Pteroceltis tatarinowii

The bark of Pteroce/tis tatarinowii is a raw material for manufacturing XuanPaper. The effects of Ca^(2+) concentrations on the accumulation of mineral elements in the bark,leaf and root of Pteroceltis tatarinowii were studied under controlled conditions. The types ofHoagland nutrient solution with three Ca^(2+) concentrations levels (200, 400 and 600 μg·g^(-1))and a control (without Ca^(2+)) were designed to culture Pteroceltis tatarinowii. After 6 months,contents of seven mineral elements including Ca, K, Mg, Mn, Zn, Cu and Na in the root, leaf and barkwere analyzed. The results indicated that Ca accumulations content in the root, leaf and bark hadpositively relation with Ca^(2+) concentrations (200, 400, 600 μg · g^(-1)), and the order of theCa content in the three components was root>leaf>bark. Ca content in the root treated with 600 μg·g^(-1) Ca^(2+) concentrations was 5.5 times as high as that of the control, and about 1.4 times ashigh as that of the root treated in 200 and 400 μg/g Ca^(2+) concentrations respectively. On thecontrary, K and Mg contents in the root, leaf and bark were negatively related to Ca^(2+)concentrations, especially in the bark, and their accumulation trend followed the order ofleaf>root>bark. K content in the bark treated with 600 μg ·g^(-1) Ca^(2+) concentrations was 39.3%of that of the control, and was 79.0% and 91.8% of that of the bark treated with 200 μg ·g^(-1)and 400 μg ·g^(-1) Ca^(2+) concentrations respectively; Mg content in the bark treated with 600μg ·g^(-1) Ca^(2+) concentrations was 23.4% of that of the control, and was 27.1% and 35.4% ofthat of the bark treated with 200 and 400 μg·g^(-1) Ca^(2+) concentrations respectively. Comparedwith the control, the general tendency of Mn, Zn and Cu content decreased with increasing of Ca^(2+)concentrations and their contents were in the order: root>leaf>bark. Based on the results of thisstudy, the experiment has been useful for providing academic bases in improving the bark quality ofPteroceltis tatarinowii on non-limestone soil.

Development of magnetocaloric materials in room temperature magnetic refrigeration application in recent six years

Some magnetocaloric materials were used successfully in magnetic refrigeration application and became one of the critical parts of magnetic refrigeration technology whose delightful progresses were made worldwide in the past 30 years. At the same time, the research on giant magnetocaloric materials will accelerate the development of room temperature magnetic refrigeration. In this paper, the new theoretical and experimental investigations on magnetic materials in room temperature application were described, including Gd and its binary and ternary intermetallic compounds, Mn-based compounds, La(Fe13-xMx)-based compounds and manganites. Based on the analysis of hysteresis, corrosion, cost and heat process, the comparison between different families of magnetic materials was discussed. Further research of room temperature magnetic refrigerant was suggested.

Molecular Simulation Study on Interaction of Thiophene Sulfides with Transition Metals

The computer molecular simulation technique was applied to study the chemisorption of thiophene and tetramethylthiophene as the model sulfides on the simple oxides and complex oxides of some transition metals as the catalytic materials. The study disclosed that the thiophene sulfides could enter into chemisorption with metal oxides such as VO, ZnO, NiO and Zn-Al-spinel. This interaction could lead to thiophene molecular structure deformation to be in an activated adsorption state, which could help to promote the conversion of thiophene sulfides in the course of catalytic cracking. The VO with a valence of 2 could provide relatively strong selective adsorption sites for the conversion of thiophene sulfides to apparently transform the molecular structures and electron cloud states of such heterocyclic sulfur compounds such as thiophene and tetramethylthiophene into an activated adsorption state. The effect of this interaction was more pronounced with respect to tetramethylthiophene.

Bainiuchang super-large silver-polymetallic ore deposit related to granitic magmatism in Mengzi, Yunnan

Bainiuchang silver-polymetallic ore deposit is located in the southeast Yunnan tin-polymetallic metallogenic belt.The probable reserves and inferred resources of the deposit are of 6 470 t Ag and 1.10 Mt Pb and 1.72 Mt Zn and 86 kt Sn.Orebodies of the deposit occur in clastic-carbonate rocks of Tianpeng Formation and Longha Formation of the middle Cambrian System above the Bainiuchang concealed granite of the late Yanshan period.The concealed granite has the characteristics of tin-bearing granites.Abundance of the mineralization elements Sn,Cu,Zn,Pb,Ag and Sb is high in the granitic rocks.Sulphur isotope data of the metal sulphides indicate that most sulphur is derived from the magmas.The ores are similar in rare earth element(REE)patterns to the granitic rocks.The granitic magma activity results in ore-bearing structures.Rocks of the Middle Cambrian System above the concealed intrusion suffer from skarnization,hornfelsing,marbleization,siliconizing and carbonatization.The mineralization elements Sn,Cu,Zn,Pb,Ag and Sb successively appear from the top of the granite to surrounding rocks.These evidences indicate that the granitic magmatism is the principal mineralization factor.The opinion that the south Bainiuchang ore field and the north Awei ore block are tin and copper potential exploration areas was put forward and was verified by drilling tests.

Effects of Different Lead Compounds on Growth and Heavy Metal Uptake of Wetland Rice

Effects of different lead compounds, PbCl2, Pb(NO3)2 and Pb(OAc)2, on the rice growth and uptake of lead and some microelements by wetland rice were studied. The results showed that the seed germination, rice seedling growth, chlorophyl content, grain yield and uptake of Pb, Cu, Zn, Fe and Mn by rice plant were affected by the chemical forms of Pb compounds added in soil to a certain degree. The germination rate and the amount of chlorophyl decreased remarkably with increasing Pb concentration, the root extension was restrained obviously by the presence of Pb, and the effect of PbCl2 was more evident than that of Pb(NO3)2 or Pb(OAc)2. The pot incubation test with yellow brown soil and red soil showed that there was no significant regularity in effect of Pb on grain yield, but the difference in the influence of various Pb compounds on yield was clearer. The effect on the amount of Pb in straw and brown rice was in the sequence of Pb(NO3)2> Pb(OAc)2> PbCl2. In case the content of Pb in brown rice was 0.5 mg/ kg, the relative loading capacities of yellow brown soil for Pb added as PbCl2, Pb(OAc)2 and Pb(NO3)2 were 100, 90 and 60 respectively. Pb uptake by wetland rice was closely related to the chemical species of Pb in soil, but there was no comparability among chemical forms of different Pb compounds in the same soil. The uptake of Cu, Zn, Fe and Mn by wetland rice was markedly affected by the addition of Pb, and different Pb compounds varied in their impacts on the uptake of other metals by different organs of wetland rice, e.g. the concentration of Fe in root increased significantly (r = 0.92), while opposite was true for Fe in brown rice (r =-0.92) due to the application of Pb(OAc), in soil. These results demonstrate that the effect of accompanying anions of Pb on the physiological and biochemical processes of wetland rice was rather complex.

Distribution and pollution assessment of trace metals in seawater and sediment in Laizhou Bay

Selected trace metals （Pb, Cd, Cu, Hg） and arsenic in seawater and surface sediments of Laizhou Bay were determined, to evaluate their spatial distribution, pollution risk and potential ecological risk. Concentrations of the elements were 0.56-2.07, 0.14-0.38, 12.70-18.40, 0.014-0.094, and 1.13- 2.37 μg/L in the seawater and 8.94-32.2, 0.18-0.67, 4.51-30.5, 0.006-0.058, and 5.75-15.3 mg/kg in sediments for Pb, Cd, Cu, Hg and As, respectively. High concentrations of the trace metals and arsenic in seawater and surface sediments were generally observed near the fiver estuary. The pollution risk result of the elements showed that Cu was the prominent trace metal pollutant in seawater, followed by Hg, Pb, Cd and As. The metal complex pollution index in seawater was at a medium level. The most important trace metal pollutant in sediments was Cd, followed by As, Cu, Pb, and Hg. Our pollution assessment suggests that trace metal pollution in Laizhou Bay sediments was at a low level. The potential ecological risk was also low in surface sediment.

Solid-state Synthesis at Low-heating Temperature and Crystal Structure of a Dinuclear Molybdenum Complex with Oxalate Ligand[Bu_4N]_2[Mo_2O_2(OH)_2Cl_4(C_2O_4)]

The title compound was synthesized by the solid-state reaction of (NH_4)_6Mo_7O_(24)·4H_2O, Na_2C_2O_4, NH_2OH·HCl and Bu_4NBr at 90 ℃ for 10 h and crystallized from acetone-ether. The green crystal belongs to the monoclinic space group P2_1/n with a=9. 908(2), b= 17, 873(2), c= 13/450(2) A , β= 90. 09(1 )°,V = 2381. 6 (7 ) A￣3 , D_c = 1. 359 g/cm￣3 , Z= 2. The structure was refined to R =0. 0427 for 2562 reflections. The anion of the title compound can be described as an oxalate ligand (C_2O4￣2 ) bridging two [MoCl_2O(OH)] units, which contain Mo(V)atoms.

Effect of Mg and Si on intermetallic formation and fracture behavior of pure aluminum-galvanized carbon-steel joints made by weld-brazing

Commercial pure aluminum and galvanized carbon steel were lap-welded using the weld-brazing(WB)technique.Three types of aluminum filler materials(4043,4047,and 5356) were used for WB.The joint strength and intermetallic compounds at the interface of three series of samples were analyzed and compared.Depending on the Si content,a variety of ternary Al-Fe-Si intermetallic compounds(IMCs) such as Fe_(4)(Al,Si)_(13),Fe_(2) Al_(8) Si(τ_(5)),and Fe_(2) Al_(9) Si_(2)(τ_(6)) were formed at the interface.Mg element in 5356 filler material cannot contribute to the formation of Al-Fe intermetallic phases due to the positive mixing enthalpy of Mg-Fe.The presence of Mg enhances the hot cracking phenomenon near the Al-Fe intermetallic compound at the interface.Zn coating does not participate in intermetallic formation due to its evaporation during WB.It was concluded that the softening of the base metal in the heat-affected zone rather than the IMCs determines the joint efficiency.

Al-matrix composite based on Al-Ca-Ni-La system additionally reinforced by L12 type nanoparticles

The structure of the quaternary Al?(2?4)wt.%Ca?Ni?La system near the aluminum corner has been studied using computational analysis in the Thermo-Calc program and experimental studies(electron microscopy,microprobe analysis and X-ray diffraction).Based on the phase equilibria data obtained,the experimental projection of the liquidus surface and solid state phase-field distribution of the Al?Ca?Ni?La system have been proposed.Microstructure studies reveal that the alloys with the 2?4 wt.%Ca,2?4 wt.%Ni and 1?3 wt.%La ranges have an ultra-fine hypoeutectic structure with 30%volume fraction of eutectic intermetallics,which allows one to classify these alloys as natural Al-matrix composites.The ultra-fine eutectic structure produces significant strengthening,the magnitude of which can be well described using the modified Orowan looping mechanism model.Small additives of Zr and Sc(0.2 and 0.1 wt.%,respectively)lead to significant strengthening(by^25%)due to the formation of L12 type phase(Al3(Zr,Sc))nanoparticles during annealing of the alloy at 350?400℃.Due to the high volume fraction of eutectic intermetallics,the new alloys have low coefficients of thermal expansion and high thermal stability of the structure and mechanical properties.

Synthesis and Crystal Structure of a Mixed Cu - Cd Bim etallic Com plex ｛〔 Cu Cd(pba)( H_2 O)_3〕·2 H_2 O｝ _n

A one dimensional bimetallic compound ｛〔CuCd(pba)(H 2O) 3〕·2H 2O｝ n in which pba was propylenebis (oxamic acid), was prepared. Crystal structure of the title compound was determined. It belongs to orthorhombic system, molecular formula CuCdC 7H 16 N 2O 11 , M r =480.17, space group Pnma(#62), a=12.953(2), b=21 626(6), c=5.253(3), V=1471(2) 3 and D x =2.17g/cm 3 for Z =4. The structure was solved by direct methods with final R =0.052 and R w =0.063 for 1055 observed reflections with I>3σ(I ). Two nitrogen atoms and two oxygen atoms from the oxamide and a water molecule coordinated to the Cu II ion forming a square pyramidal geometry. Four oxygen atoms from the oxamide and two water molecules coordinated to the Cd II ion forming an elongated octahedral geometry.

Statistical Analysis of the Hole Primary Halo in Dachang Sn-Zn Polymetallic Mining Area of Guangxi

The complexity and diversity of Ore forming is the commonness, of which the difficulty is the evolutional characteristics of geochemical elements. The metallogetie process can be speculated and get useful and microcosmic message for next exploration. In this paper, the research of cluster analysis and factor analysis of the hole primary halo in Dachang Sn-Zn polymetallic mining area in Guangxi reveal that metallogenic process is very complex and superposed by mineralization . It is considered that the enrichment of Zn, Sn superposed anaphase. By sulphide polymetallic, Au is very independency and that Sb, Pb, Ag and Cu are proximal indicator elements for exploring Zn, Sn in the mine.

Carbon Paste Electrodes for the Analysis of Some Agricultural Pollutants and Trace Metals

The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode （TCP-CPE） and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode （BiF-TCP-CPE）. The TCP-CPE was examined with the main objective of using it for the differential pulse voltammetric analysis of some neonicotinoid insecticides in aqueous Britton-Robinson buffer solution pH 7.0 as supporting electrolyte. After comparing the performance of the TCP-CPE with that of silicone oil carbon paste electrode, quantitative analysis of imidacloprid, thiamethoxam and clothianidin was performed in model solutions and real samples （river water and commercial insecticide formulations）. The in situ prepared BiF-TCP-CPE was tested for a simultaneous detection of selected heavy metal ions （Cd^2＋ and Pb^2＋） at a μg/dm^3 concentration level, using square wave anodic stripping voltammetric technique. The influence of different electrochemical pretreatments of the working electrode on the bismuth deposition and analyte signals were investigated. Film formation was studied at untreated, pre-cathodized and pre-anodized TCP-CPEs in the acetic buffer solution pH 4.6, containing 1 μg/cm^3 Bi （III）.

Crystal Structures of Ln(NO_3)_3(Ln=La,Yb) Complexes with 12-crown-4

The synthesis and crystal structures of Ln(NO3)3(Ln=La,Yb) complexes with 12-crown-4 are reported. La (NO3 )3 (12-crown-4) (H2O)x(Ln=La,x=1; Ln=Yb, x=0), Mr=519. 2(535.3), space group P21/n(P21/c)with α =7. 612(2)(12. 116(3)), b=13. 932(6) (8. 544(3)),c= 16. 179(6) (15.241 (3));β=101.40 (2)( 91.82 (2))°; V=1682 (1) (1577(1)); Z=4 (4);μ(MoKα)=26.7(63.2) cm -1; F(000) =1024 (1036) ; R=0. 035 (0. 034) ; Rw= 0. 028 (0.036) for 1665 (1594) observed reflections with Ⅰ>3σ(Ⅰ). The La(Ⅲ) ion in La (NO3)3 (12-crown-4) (H2O) is 11-coordinated, being bonded to three bidentate nitrate ions , four oxygen atoms of the crown molecule and one oxygen atom of a water molecule. Yb(NO3)3 (12-crown-4) is a 10-coordinated complex, in which the metal ion bonds with three bidentate nitrate ions and four oxygen atoms of a crown ether.

Trace Metals in PM_(2.5):A Story beyond Border

In a lab of the CAS Institute of Process Engineering（IPE）in Beijing,Winifred Uduak Anake,a visiting woman scientist from Covenant University.Nigeria was dashing to finish testing the 100 plus samples she collected from her home country.＂1 am trying to find out the type and amount of hazardous trace metals bound to the tiny particles trapped on the filters,＂she explained：＂out of worries about their possible threat to human health.＂Before concluding her three-month stay she needed to complete examining the morphology of the particles,total trace metals,

Water Quality Monitoring of the Bezerra River （Cascavel, Brazil） Using SR-TXRF Technique

The present study aims to monitor and assess the water quality of the Bezerra River located in the Western Brazilian Parana state. For the monitoring of river waters, six samplings were established per month during one year. As indicators of the water quality, physico-chemical parameters such as water temperature, pH, turbidity, dissolved oxygen and COD （chemical oxygen demand） were chosen, as well as trace and majority element concentrations. It is noteworthy that the mean annual values of conductivity, turbidity and COD have progressively increased along the river with maximum values after the Cascavel western sewage treatment plant. Only 13 elements were found in the six collection points, but the metallic elements Cr, Mn, Fe, Cu and Zn have shown concentrations above the maximum limits recommended by Brazilian environmental legislation, suggesting the presence of highly polluting anthropogenic sources. Correlation analyses were used to determine the spatio-variability of water quality variables. The six collection sites were grouped into two clusters, with the element composition in the first cluster （sites 1, 2 and 6） being due to strong anthropogenic activities. The study of the Bezerra River water quality could help to develop municipal environmental policies and help with the management of water conservation in the Bezerra River basin.

Molecular Structure of Organolanthanide Complex ［（η~5－CH_3C_5H_4）_2Tb（μ－Cl）（THF）］_2

The complex [(η5-CH3C5H4)2Tb(μ-Cl) (THF)]2, has been studied by X-ray crystallography. The crystal is orthorhombic , space group Phcn with a= 20.414(2),b=9. 548(1),c=16.390(6)A.V=3194.9(6) A3, Mr=849.46,Z=4,Dc=1.77 g/cm3, F(000)=1664,μ=46.37 cm-1.The Tb3+ ion is coordinated by two CH3C5H4 groups, two chloride ions and one oxygen atom from tetrahydrofuran to form a distorted trigonal bipyramidal geometry. Two bridging Tb-Cl bond lengths are 2. 716(2) and 2.790(2)A,respectively.The Tb-O (THF) and average Tb-C(CH3C5H4) bond lengths are 2.559(6) and 2.670(4)A,respectively.

Study on the Reaction Behavior of Some Trinuclear Complexes of Transition Metals: [Fe_2M(μ_3-O) (μ-O_2CCH_3)_6(H_2O)_3]·xH_2O by the Method of Probe Reaction of Acetic Acid

The reaction behaviors of the title complexes have been studied in thesystem of dinitrogen gas by means of in situ IR. It has been found that some activefragments created at some stage of the thermal decomposition process of the complexes.enable.the acetic acid both obtained from the ligand of the complexes and introducedfrom outside to convert to acetone by decarboxylation. Their optimum reaction temperatures are of 240~270℃ for [Fe2MnO(O2CCH3),(H2O)3], 290~320 C for [Fe3Q(O2CCH3)6(H2O)3], 300~330℃ for [Fe2CoO(O2CCH3),(H2O)3] and 320~ 350℃for [Fe2NiO(O2CCH3)6(H2O)3], indicating the lowering sequence of the activity of active species. At the same time it has been shown that this activity may come from thejoined contributions of both the coordinating capability of the hetero-metals in the complexes and their structural factors. On the basis of the TGA, DTA and EI-MS data,the composition of the active fragments has been tentatively inferred as [Fe2MnO(O2CCH3)3-2].

New family of Dirac and Weyl semimetals in XAuTe(X=Na, K,Rb) ternary honeycomb compounds

We propose a new family of 3D Dirac semimetals based on XAuTe(X = K, Na, Rb) ternary honeycomb compounds, determined based on first-principles calculations, which are shown to be topological Dirac semimetals in which the Dirac points are induced by band inversion. Dirac points with four-fold degeneracy that are protected by C3 rotation symmetry and located on the Γ-A high-symmetry path are found. Through spatial-inversion symmetry breaking, a K(Au0.5 Hg0.5)(Te0.5As0.5) superlattice structure composed of KHgAs and KAuTe compounds is proven to be a Weyl semimetal with type-II Weyl points, which connect electronand hole-like bands. In this superlattice structure, the six pairs of Weyl nodes are distributed along the K-Γ high-symmetry path on the kz = 0 plane. Our research expands the family of topological Dirac and type-II Weyl semimetals.