Effect of calcium compounds on direct reduction and phosphorus removal of high-phosphorus iron ore

The increasing demand for iron ore in the world causes the continuous exhaustion of magnetite resources.The utilization of high-phosphorus iron ore becomes the focus.With calcium carbonate(CaCO_(3)),calcium chloride(CaCl_(2)),or calcium sulfate(CaSO_(4))as additive,the process of direct reduction and phosphorus removal of high-phosphorus iron ore(phosphorus mainly occurred in the form of Fe_(3)PO_(7) and apatite)was studied by using the technique of direct reductiongrinding-magnetic separation.The mechanism of calcium compounds to reduce phosphorus was investigated from thermodynamics,iron metallization degree,mineral composition and microstructure.Results showed that Fe_(3)PO_(7) was reduced to elemental phosphorus without calcium compounds.The iron-phosphorus alloy was generated by react of metallic iron and phosphorus,resulting in high phosphorus in reduced iron products.CaCO_(3) promoted the reduction of hematite and magnetite,and improved iron metallization degree,but inhibited the growth of metallic iron particles.CaCl_(2) strengthened the growth of iron particles.However,the recovery of iron was reduced due to the formation of volatile FeCl_(2).CaSO_(4) promoted the growth of iron particles,but the recovery of iron was drastically reduced due to the formation of non-magnetic FeS.CaCO_(3),CaCl_(2) or CaSO_(4) could react with Fe_(3)PO_(7) to form calcium phosphate(Ca_(3)(PO_(4))_(2)).With the addition of CaCO_(3),Ca_(3)(PO_(4))_(2) was closely combined with fine iron particles.It is difficult to separate iron and phosphorus by grinding and magnetic separation,resulting in the reduced iron product phosphorus content of 0.18%.In the presence of CaCl_(2) or CaSO_(4),the boundary between the generated Ca_(3)(PO_(4))_(2) and the metallic iron particles was obvious.Phosphorus was removed by grinding and magnetic separation,and the phosphorus content in the reduced iron product was less than 0.10%.

The use of yellow phosphorus to destroy toxic organic compounds

A new method for generating reactive species to destroy toxic organic chemicals has been developed. This method reacts yellow phosphorus with O_2, in moist air to produce species such as O,O_3, PO, and PO_2, which are capable of reacting with various types of organics. Toxic organic com-pounds are converted to small molecular wight organic acids, aldehydes, and/or alcohols, while yel-low phosphonis is oxidital into phosphoric acid, which may be recovered as a valuable byproduct.This technique has ben demonstrated to be effective for destroying many types of toxic organiccompounds. including PAH, aromatic chlorides, amines, alcohols, and acids, nitro-aromatics,heterocyclic hydrocarbons, PCB, aliphatic chlorides and sulfides, dyes, and pesticides.

The Generation of a Reduced Mechanism for Flame Inhibition by Phosphorus Containing Compounds Based on Path Flux Analysis Method

In order to analyze the complex chemical kinetic mechanism systematically and find out the redundant species and reactions, a numerical platform for mechanism analysis and simplification is established basing on Path Flux Analysis （PFA）. It is used to reduce a detailed mechanism for flame inhibited by phosphorus containing compounds, a reduced mechanism with 65 species and 335 reactions is obtained. The detailed and reduced mechanism are both used to calculate the freely-propagating premix C3H8/air flame with different dimethyl methylphosphonate doped over a wide range of equivalence ratios. The concentration distributions of free radicals and major species are compared, and the results under two different mechanisms agree well. The laminar flame speed obtained by the two mechanisms also matches well, with the maximum relative error introduces as a small value of 1.7%. On the basis of the reduced mechanism validation, the correlativity analysis is conducted between flame speed and flee radical concentrations, which can provide information for target species selection in the further mechanism reduction. By analyzing the species and reactions fluxes, the species and reaction paths which contribute the flame inhibition significantly are determined.

SYNTHESIS OF FUSED PHOSPHORUS HETEROCYCLIC COMPOUNDS(II)

Using cation exchange resin(D72,Amberlyst-15) as catalyst, Mannich-type reaction of 5-amino-1,2,4-triazole 1, containing guanidine substructure, provides an efficient synthesis of a new kind of bicyclic P- and N-containing compounds, 6-phospha-4,5,6-trihydroimidazolo [2,3-e] 1,2,4-triazole 4.

Arbuscular mycorrhizal fungal colonization of Glycyrrhiza glabra roots enhances plant biomass,phosphorus uptake and concentration of root secondary metabolites

Arbuscular mycorrhizal （AM） fungi penetrate the cortical cells of the roots of vascular plants, and are widely distributed in soil. The formation of these symbiotic bodies accelerates the absorption and utilization of min- eral elements, enhances plant resistance to stress, boosts the growth of plants, and increases the survival rate of transplanted seedlings. We studied the effects of various arbuscular mycorrhizae fungi on the growth and devel- opment of licorice （Glycyrrhiza glabra）. Several species of AM, such as Glomus mosseae, Glomus intraradices, and a mixture of fungi （G. mosseae, G intraradices, G. cladoideum, G microagregatum, G caledonium and G. etunica- tum） were used in our study. Licorice growth rates were determined by measuring the colonization rate of the plants by the fungi, plant dry biomass, phosphorus concentration and concentration of secondary metabolites. We estab- lished two cloned strains of licorice, clone 3 （C3） and clone 6 （C6） to exclude the effect of genotypic variations. Our results showed that the AM fungi could in fact increase the leaf and root biomass, as well as the phosphorus con- centration in each clone. Furthermore, AM fungi significantly increased the yield of certain secondary metabolites in clone 3. Our study clearly demonstrated that AM fungi play an important role in the enhancement of growth and development of licorice plants. There was also a significant improvement in the secondary metabolite content and yield of medicinal compounds from the roots.

Synthesis of 2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide, A New Potential Antitumor Phosphorus Heterocycle Compound

2-methoxy-6-oxo-1, 4, 2-diazaphosphorinane-2-oxide 8, phosphorus counterpart of 2, 6-dioxopiperazine, was synthesized as antitumor agent. The new phosphorus heterocycle compound 8 is the key intermediate in the synthesis of phosphorus counterpart of bisdioxopiperazine.

Extraction of Tungsten and Molybdenum by Various Organic Compounds as Extractants

Seventy organic compounds including various organophosphorus esters, amines and oxygen-based ligands were investigated as extractants. The experiment results show that amines are excellent extractants for W and Mo. Their sequence of extraction ability for W is as follows: quarternary amine > tertiary amine > secondary amine > primary amine. Acidic organophosphorus extractants do not extract W, but can extract Mo with high extraction ability from the acidic solution. These extractants could provide a potential process for separating W from Mo.

Bone Metabolic Disorders due to Antiepileptic Drugs and Therapeutic Effects of Vitamine D_2

Bone Mineral Content(BMC), serum cal-cium, phosphorus and AlP were measured in64 epileptic patients on long term treatmentwith one or two kinds of antiepileptic drugs(AEDs) ,and in 14 epileptic patients not tak-ing AEDs. In the epileptic patients takingAEDs, the BMC value was 0.645±0.020g/cm^2,significantly lower than 0.693±0.022g/cm^2, theBMC value of the control group (P【0.01).

One-Electron-Addition to Pentavalent Phosphorus with the Phosphorus-Chlorine Bond as Acceptor Introducing a Fundamental Distinction in Substitution Mechanism between S_N2(P) and S_N2(C)

An electron-addition, under single-crystal conditions, to pentavalent phosphorus compounds as Cl-P (=O, S) Y, Z with the P-Cl bond as electron-accepting group, is selected as an additional model for SN2(P) like reactions. It is demonstrated that the geometric information stored in the tetrahedral configuration (substrate) can be transmitted in the corresponding trigonal bipyramidal (TBP) state for nucleophilic substitution. In this article, we focus on these specific mechanistic aspects of carbon and phosphorus. We consider our study as a contribution to the significance of these (bio)chemical intermediates.

Stereodivergently asymmetric synthesis of chiral phosphorus compounds by synergistic combination of ion-pair catalyst and base

Stereodivergently constructing the designed products having adjacent multi-stereocenters via a given reaction,with excellent control of both absolute and relative configurations,presents one of the substantial hurdles in asymmetric catalysis.Herein,we report a precisely stereodivergent asymmetric protocol by synergistic combination of phosphonium-involved ion-pair catalysis and base for accessing to chiral phosphorus compounds bearing two adjacent chiral centers particularly containing an acidic protonated enantioenriched carbon atom,having broad functional group compatibility in both dynamic and thermodynamic processes under mild reaction conditions.Two keys for the success in constructing these stereoisomers with high levels of regio-,diastereo-,and enantioselectivities were contained:firstly,the precise stereo-control in providing dynamic products was enabled by bifunctional phosphonium salt catalyst with semi-enclosed cavity;secondly,the readily stereospecific transformation of adducts from dynamic to thermodynamic version was initiated by achiral base.All four stereoisomers could be readily accessed even in gram-scale in high yields with maintaining excellent stereoselectivities,illustrating the potential of this synergistic catalytic methodology in organic synthesis.Moreover,mechanistic studies including density functional theory(DFT)calculations and control experiments provide insights into the mechanism.

Retention and chiral recognition mechanism of organo-phosphorus compounds in high-performance liquid chromatography

In normal phase condition, a series of chiral phosphorus organic compounds have been separated by high-performance liquid chromatography. In order to study the retention and chiral recognition mechanism, the method of quantitative structure-enantioselectivity retention relationships (QSERRs) has been investigated from the quantitative equations established between the chromatographic retention of enantiomers and their molecular descriptors of physicochemical properties. The results show that on the Pirkle-type chiral stationary phase (CSP) of Sumichiral OA4700, it is the parameter of LUMO that gives the most contribution to the chromatographic retention of O-ethyl O-(substituted) phenyl N-isopropyl phosphoroamidothioates resulting from the interaction of hydrogen bond and (or) π-π interaction. Meanwhile, the chiral recognition is formed from the contribution of logP and LUMO.

Synthesis of a New Class of Highly Functionalized Phosphorus Ylides Containing Heterocyclic Compounds

The zwitterionic intermediate generated from the reaction of triphenylphosphine with electron deficient acety- lenic compounds was trapped by various NH acids. The synthesis resulted in a new class of highly functionalized heterocyclic compounds. Some of the reactions produced E and Z isomers. And the stability and transformation of them were studied by dynamic 1H NMR and density functional theory （DFT） calculations.

Introducing Covalent Metal-Phosphorus Bonds into Intermetallic Platinum-Based Catalysts for High-Performance Fuel Cells

The inadequate performance of oxygen reduction reaction(ORR)catalysts hampers the development of proton exchange membrane fuel cells(PEMFCs).Herein,we proposed an approach to tackle this problem by modulating the chemical bond type of intermetallic Pt-based catalysts,using phosphorus(P)doped L1_(0)-PtFeGa_(0.1)/C(P-L1_(0)-PtFeGa_(0.1)/C)as a proof of concept.X-ray absorption spectroscopy(XAS)demonstrated that the doped P transferred electrons to Pt,and thus,modified the electronic structure of Pt,weakening the adsorption strength with oxygen-containing species.Therefore P-L1_(0)-PtFeGa_(0.1)/C showed 13 times mass activity(MA)compared with commercial Pt/C,with a decay of only 28%after 100,000 potential cycles.When equipped in the membrane electrode assembly,the P-L1_(0)-PtFeGa_(0.1)/C catalyst also exhibited a remarkable activity(MA=0.84 A mgPt^(−1)at 0.9 V)and stability(MA retention=72%and voltage loss=9 mVat 0.8 A cm^(−2)after 30,000 cycles),making it one of the best performers among recorded Pt-based catalysts.Theoretical studies demonstrated that the doping of P optimized the adsorption energy between Pt and oxygen intermediates through sp-d orbital interactions and prevented metal dissolution by forming stronger Pt-P covalent bonds compared with Pt–Pt bonds.

The role of 3d orbitals in the bonding of phosphorus compounds

Ab initio LCAO-MO-SCF calculations for several typical molecules containing phosphorus have been undertaken to study the role of phosphorus 3d orbitals in the bonding.It is emphasized that the discussion about the 3d orbital participation in bonding should be based on a reasonable choice of basis sets and it seems suitable to choose the atomic orbitals in proper molecular environment as the basis set.As an approximation,the optimized minimal STO-NG basis sets have been adopted in the present paper.The results obtained well exhibit the model of 3d orbital participation in bonding. It is shown that under the influence of highly electronegative ligands the phosphorus 3d orbitals con- tract greatly,their energy levels drop considerably,and thus they can effectively participate in bond- ing.The presence of highly electronegative ligands seems necessary.The contribution of 3d orbitals to bonding is achieved mainly through the concertedformation of σ bonds and p-d backbonds,though the contribution to σ bonding is minor.The three-center,four-electron bond modelis only approxi- mately correct.The results of the present paper demonstrate that the model of 3d orbital participation in bonding favoured by experimental chemists is reasonable and possesses sound ground.

急性白血病肝浸润^(31)P磁共振波谱学分析及临床意义

目的:通过对白血病肝脏浸润(LIL)病例与正常对照组的肝脏二维化学位移磁共振31磷波谱成像(2D CSI31P MRS)对照研究,探讨LIL的肝脏磷化合物代谢特征变化。方法:收集LIL15例,并与12例正常肝脏作对照,进行2D CSI31P MRS肝脏扫描,检测各种磷代谢物包括磷酸单酯(PME)、磷酸双酯(PDE)、三磷酸腺苷(ATP)、无机磷(Pi)的相对值,经体模所测校正系数校正后,分析PME、PDE、Pi、ATP的校正相对值(以下简称相对值),及PME/PDE、PME/ATP、PDE/ATP、Pi/ATP、PME/(PME+PDE)的比值变化。结果:在所测的肝脏磷代谢物相对值中,仅LIL组的PME相对值升高,为1.992±0.876,与对照组(1.167±0.427)相比有显著性差异,P<0.05;其它各磷代谢物相对值均无差异。比较LIL与正常对照组之间磷代谢物比值,发现LIL组中与PME相关的比值包括PME/PDE、PME/ATP和PME/(PME+PDE)比值升高,分别为0.551±0.339、1.402±0.654和0.326±0.13,与对照组(分别为0.254±0.059、0.792±0.232和0.199±0.049)相比有显著性差异,P<0.01;LIL组的其它磷代谢物比值与对照组相比均无显著差异。结论:肝31P MRS检查为LIL提供新的非创伤性检测和评价方法,肝脏PME相对值及其相应比值升高提示白血病患者肝浸润存在的可能。

复方α-酮酸片对维持性血液透析患者营养状态、钙磷代谢及炎性因子的影响

目的:探讨复方α-酮酸片对维持性血液透析患者营养状态、钙磷代谢及炎性因子的影响。方法:选取维持性血液透析患者84例,按照就诊顺序随机分为观察组和对照组两组,各为42例。对照组单纯给予维持性血液透析治疗,观察组在对照组的基础上加用复方α-酮酸片,比较两组治疗前后血清总蛋白(TP)、血清白蛋白(ALB)、血红蛋白(HB)、转铁蛋白(TRF)、血钙(Ca)、血磷(P)、钙磷乘积(Ca×P)、血清全段甲状旁腺素(iPTH)收、白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)及超敏C反应蛋白(hsCRP)的变化情况。结果:观察组治疗后TP、ALB、HB、TRF均明显高于对照组,差异具有统计学意义(P<0.05),而血P、血Ca×P、血清iPTH明显低于对照组,差异具有统计学意义(P<0.05),血清IL-6、TNF-α及hs-CRP水平明显低于对照组,差异具有统计学意义(P<0.05)。结论:复方α-酮酸片能够有效改善血液透析患者的营养状态,维持其钙磷代谢平衡,并能降低炎性反应,值得临床推广和应用。

12种取代苯胺形成P450－MI组合物的定量结构与活性关系

本文用逐步多元回归分析法导出了１２种取代苯胺的Ｈａｎｓｃｈ理化参数与取代苯胺形成细胞色素Ｐ４５０（简称Ｐ４５０）─代谢中间体（简称ＭＩ）络合物能力的定量结构与活性关系（ＱＳＡＫ）的相关方程式。结果表明，取代基的电性参数之和Σσ、脂溶性参数之和Σπ与形成Ｐ４５０－ＭＩ络合物的活性大小具有较好的相关性。对位存在含孤对电子的取代基使活性增大。本文还用分子轨道法ＭＮＤＯ－ＰＭ３计算了这些化合物的电子结构参数，没有得到具有统计意义的电子结构参数与活性之间的定量相关方程式。

LPE Growth of InAsPSb on InAs:Melt Composition,Lattice Mismatch and Surface Morphology

The LPE growth of quaternary InAs11-x-yPxSby with x = 0.2 and y = 0.09 on InAs substrate has been studied. This composition is very suitable for the laser and detector applications at about 2.5 μm. We show that in InAsPSb/InAs system there is a determinate relation between the surface morphology and the lattice mismatch of the epi-wafers, by which we can easily control the melt composition to grow high quality hetero-structures. The reason has been discussed. The p-n junctions with fairly good carrier profile have been prepared in this system.