低热固相合成磷酸镧及其结晶度

对合成功能材料磷酸镧的新方法进行了研究，以聚乙二醇-400 （PEG-400）为表面活性剂，LaNO₃•6H₂O和(NH₄)₃PO₄•3H₂O为原料，用低热固相反应法成功合成得到磷酸镧。用产物XRD图谱数据计算得到的结晶度作为试验的考察指标，试验中应用了均匀设计试验法及数据挖掘技术，在数据挖掘成果的指导下进行了试验。试验结果表明，用最优工艺条件合成得到的产物为23nm的LaPO₄∙0.5H₂O，结晶度为97.8%与数据挖掘得到的最佳结果相吻合。TG/DTA分析结果表明LaPO₄∙0.5H₂O在300℃下加热脱水可以转变成为LaPO₄。     

酸性离子液体中苯甲醇催化氧化合成苯甲醛

在没有任何有机溶剂和卤素的条件下，以30%H₂O₂为氧化剂，Na₂WO₄·2H₂O为催化剂，在酸性离子液体[(CH₂)₄SO₃HMIm]TSO中，研究了苯甲醇选择性氧化合成苯甲醛。在n(苯甲醇)∶n（H₂O₂）∶n(离子液体)∶n(Na₂WO₄·2H₂O)=40∶48∶1∶1、90 ℃和3 h条件下，催化效果最好，此时苯甲醇转化率为90.1%，苯甲醛选择性为92.1%。反应结束后，产物和离子液体分层，通过简单的倾倒即可分离产物。分离后的离子液体经真空干燥脱水后重复使用4次，催化活性基本不变。     

Synthesis of tributyl citrate catalyzed by Ce(SO4)2·4H2O/ NH2SO3H

研究了柠檬酸与正丁醇在Ce(SO₄)₂·4H₂O/ NH₂SO₃H复配催化剂催化作用下制备柠檬酸三丁酯的工艺条件。实验结果表明Ce(SO₄)₂·4H₂O/ NH₂SO₃H催化合成柠檬酸三丁酯的最佳反应条件为：醇酸摩尔比为4.0∶1,催化剂用量为1.5%（以柠檬酸质量计）,m[Ce(SO₄)₂·4H₂O]∶m(NH₂SO₃H)=2∶1,反应温度为150 ℃,反应时间为7 h,酯化率＞98.5%,精制后产品纯度>99.5%。     

BiVO4合成及其光催化性能

以Bi(NO₃)₃·5H₂O和 NH₄VO₃为原料,水热法合成了可见光催化剂BiVO₄,进行紫外-可见漫反射实验、XRD和BET表征。研究了pH、催化剂合成水热温度和催化反应时间对4BS溶液进行光催化降解效果的影响。确定最佳条件为:pH=7.00,水热合成催化剂温度160 ℃,水热时间2 h,在此条件下,光照210 min后,染料脱色率可达98.9%。水热合成的新型纳米催化剂BiVO₄具有良好的可见光催化活性。     

异丁烯两段催化氧化制甲基丙烯酸催化剂的研究* Ⅱ.甲基丙烯醛气相氧化制甲基丙烯酸的杂多酸盐催化剂的研究

本文报道用于甲基丙烯醛(MAL)选择氧化制甲基丙烯酸(MAA)的PMoV杂多酸盐催化剂的研究结果。IR和XRD考察结果表明,本文所研究的催化剂均具有稳定的Keggin结构,催化剂物相组成为H_4-2y-zPO₄(MO₃)_12-x(VO₃)_xCu_yCs_z。在300 ℃,原料气组成MAL:H₂O:O₂:N₂=1:10:3:32,体积空速1 200 h^-1的条件下,最佳催化剂的MAL转化率为94.1%,选择性达88.7%。     

稀土双膦酸酯配合物和稀土氯化物对Mannich反应的催化作用

研究了Dy(OTf)₃、DyCl₃和稀土双膦酸酯配合物{ ［Dy(OTf)₂L₂(H₂O)₂］(OTf)(CH₃CN)}［L=(iPrO)₂P(O)CH₂P(O)(iPrO)₂］ 等对Mannich 反应的催化作用,发现以Dy(OTf)₃为催化剂时,收率为54%,［Dy(OTf)₂L₂(H₂O)₂］(OTf)(CH₃CN)的收率仅为8%,DyCl₃收率达47%。研究了12种稀土金属氯化物对Mannich 反应的催化作用,其中,ErCl₃催化剂的收率最高,达到61%。     

烟气气相组分及Ca（OH）2对KMnO4氧化NO的影响机理

在固定床反应器中考察了KMnO₄氧化烟气中NO的过程,分析了烟气组分H₂O、O₂及SO₂对NO氧化过程的影响规律,得到了Ca（OH）₂对KMnO₄氧化NO的影响机理。实验结果表明,H₂O是KMnO₄氧化NO的必要条件;在含H₂O条件下,O₂可以提高NO氧化率。SO₂与氧化剂反应生成无水钾镁钒类复盐K₂Mn₂（SO₄）₃对NO氧化具有负面作用;Ca（OH）₂的加入提高了氧化剂表面的固体碱度从而促进氧化过程进行;通过添加Ca（OH）₂可以降低SO₂对NO氧化过程的负面影响。根据气体成分和产物分析可知,KMnO₄在钙基吸收剂表面氧化烟气中NO的机理可能是KMnO₄以离子态将吸附在氧化剂表面的NO和SO₂氧化为NO₂和SO₃,生成的NO₂、SO₃再传递到氧化位临近的碱性位被吸收。     

新型层状粘土结构F-T合成催化剂的研制

用FeCl₃·6H₂O和Na₂SiO₃水玻璃共沉淀法制备蒙脱土结构的新型F-T合成催化剂。用XRD、SEM和N₂低温吸附-脱附等方法对催化剂的物相结构进行测定,确认催化剂具有层状结构并有较高的比表面积。催化剂经过预处理,F-T合成在浆态床反应器中进行,反应条件：270 ℃,0.5 MPa,气流量34.5 mL·min^-1,n(H₂)∶n（CO）=2∶1,反应时间6 h。产物分析得知,C₉～C₂₅烃类的选择性达到90%以上,使ASF分布规律发生正偏移。     

烟气气相组分及Ca(OH)_2对KMnO_4氧化NO的影响机理

在固定床反应器中考察了KMnO₄氧化烟气中NO的过程,分析了烟气组分H₂O、O₂及SO₂对NO氧化过程的影响规律,得到了Ca（OH）₂对KMnO₄氧化NO的影响机理。实验结果表明,H₂O是KMnO₄氧化NO的必要条件;在含H₂O条件下,O₂可以提高NO氧化率。SO₂与氧化剂反应生成无水钾镁钒类复盐K₂Mn₂（SO₄）₃对NO氧化具有负面作用;Ca（OH）₂的加入提高了氧化剂表面的固体碱度从而促进氧化过程进行;通过添加Ca（OH）₂可以降低SO₂对NO氧化过程的负面影响。根据气体成分和产物分析可知,KMnO₄在钙基吸收剂表面氧化烟气中NO的机理可能是KMnO₄以离子态将吸附在氧化剂表面的NO和SO₂氧化为NO₂和SO₃,生成的NO₂、SO₃再传递到氧化位临近的碱性位被吸收。     

模拟土壤介质中仿古铸铁腐蚀产物的形貌及其生长过程

采用金相、显微激光拉曼和X射线衍射等技术研究了仿古铸铁在模拟土壤介质(0.06 mol•L^-1 NaCl+0.03 mol•L^-1 Na₂SO₄+0.01 mol•L^-1 NaHCO₃溶液)中的腐蚀形态、腐蚀产物的形貌及其生长和发展过程.结果表明,在最初的34 h内,铸铁发生铁的选择性腐蚀,在试样表面留下许多白色圈状的Fe(OH)₂沉淀,圈内则是分散状的Fe(OH)₂;浸泡120 h时,观察到试样表面有一层深绿色的腐蚀产物,其组分主要为GR(Cl^-)（化学式为Fe^Ⅱ₃Fe^Ⅲ（OH）₈Cl•2H₂O）和GR(SO^2-₄)（化学式为Fe^Ⅱ₄Fe^Ⅲ₂（OH）₁₂SO₄•2H₂O）,绿锈表面呈黄色;约288 h后,腐蚀产物呈现分层,内层主要由黑色结晶状的FeO和Fe₃O₄组成,外层主要为疏松多孔的砖红色γ-FeOOH,后者是铁器表面的一种有害锈.     

Magnesium monophosphate cements derived from diammonium phosphate solutions

Rapid-setting magnesium monophosphate cementitious materials were prepared by mixing calcined magnesium oxide (MgO) powder with an aqueous solution of diammonium phosphate (ADP) at 24°C. The activation energy for the curing reaction of the cement paste was determined to be 30.29 kcal/mole, and at age 1 hr the compressive strength was ≈900 psi (6.2 MPa). X-ray diffraction studies of the cured cement indicated that the major reaction product was magnesium orthophosphate tetrahydrate [Mg₃(PO₄)₂·4H₂O]. Magnesium ammonium phosphate hexahydrate [MgNH₄PO₄·6H₂O] and Mg(OH)₂ were also detected. Subsequent heating of the cement to 1300°C resulted in the conversion of the three compounds to a single phase of anhydrous magnesium orthophosphate [Mg₃(PO₄)₂]. The resultant product had a compressive strength of 7000 psi (48.23 MPa) and was thermally stable in air at temperatures >1000°C.     

288 K下Li+,K+//CO2-3,B4O2-7-H2O四元体系的相平衡

Solubilities and properties (density, conductivity and pH value) of solutions in the quaternary system Li⁺,K⁺//CO^2-₃,B₄O^2-₇-H₂O at 288 K were experimentally studied with the isothermal equilibrium method. The phase diagram of the system consisted of two invariant points E and F, five univariant curves, and four crystallization fields that belonged to K₂CO₃·3/2H₂O,Li₂B₄O₇·3H₂O,K₂B₄O₇·4H₂O and Li₂CO₃. The composition of the solution corresponding to E was w（CO^2-₃）=2.27 %,w（B₄O^2-₇）=6.05 %,w（K⁺ ）=4.30%,w(Li⁺)=0.30 % and the equilibrium solids were Li₂B₄O₇· 3H₂O+K ₂B₄O₇·4H₂O+Li₂CO₃;The composition of the solution for F was w(CO^2-₃)=22.45%,w(B₄O^2-₇)=1.88%,w(K⁺ )=29.96%,w(Li⁺ )=0.03% and the equilibrium solids were K₂CO₃·3/2H₂O+K ₂B₄O₇·4H₂O+Li₂CO₃. K₂CO₃ possesses strong salting-out effect on K₂B₄O₇,Li₂CO₃ and Li₂B₄O₇.     

Kinetics of the Decolorization by Fenton's Reagent

Fenton's reagent was employed in the decolorization of aqueous solutions of one of three dyestuffs (Acid Red 27, Reactive Blue 81, Acid Blue 62). The decolorization with Fenton's reagent was found to be simple and fast. In order to determine the reaction kinetics of the decolorization the stopped-flow technique under pseudo-first order conditions was used. Experiments were carried out at pH=2, at the excess of ferrous salts (FeCl₂·4H₂O or FeSO₄·7H₂O). The rate constants of the decolorization determined by us are in the same order of magnitude: 90 to 100 dm³/(mol-s) for FeSO₄·7H₂O/H₂O₂, and 40 to 50 dm³/(mol-s) for FeCl₂·4H₂O/H₂O₂ systems. The difference between the rate constants for both ferrous salts indicates that the Fenton's reaction may proceed via different mechanisms.     

以粉煤灰为原料制备高纯氧化铝

引言 粉煤灰是电厂排放的废弃物,到2000年我国排放量已达12000万吨[1],给环境造成了巨大的污染,因此开展粉煤灰的综合利用具有长远的战略意义.     

New open-framework beryllium phosphates with hcb,sql, and bnn topologies

Three new beryllium phosphates, namely, H₃aep·Be₂(PO₄)₂(H₂PO₄)·H₂O (1), H₂tmdp·Be₃(HPO₄)₃(PO₄CH₃)·2.25H₂O (2), and H₂dmpda·Be₃(PO₄)(HPO₄)₂(H₂PO₄) (3), were prepared under solvothermal conditions. These compounds display different open-framework structures with hcb (for 1), sql (for 2), and bnn (for 3) topologies, respectively. The formation of phosphate ester from in situ esterification reaction of phosphoric acid and methanol is noteworthy.     

Isomer Directed Synthesis of Two 3D Cadmium(II) Compounds: Structure Variation and Energetic Performance

Two inorganic mixtures of copper and sodium compounds have been synthesized and characterized with different measurement techniques. The thermal property of these mixtures has been studied to low temperature up to 223 from 573 K with DSC. The specific heat capacity of this mixture has been measured in atmospheric O₂ at a rate of 10 K min^?1 from 573 to 223 K and vice versa in two thermal cycles. The net specific heat capacity of these mixtures is found endothermic in first and second thermal cycles. The net specific heat capacity of 0.5Cu₂(PO₄)(OH); 3.5CuH(PO₄)₂·H₂O; 2NaHSO₄·H₂O (CuPHS) during first thermal cycle is ?71203.05 J kg^?1 K^?1 and in second thermal cycle is ?73881.67 J kg^?1 K^?1 between temperature range of 303–223 K. The net specific heat capacity of mixture 0.5Cu₂(PO₄)(OH); 3.5CuH(PO₄)₂; 2Na₂SO₄(CuPS) in first thermal cycle is ?21158.37 J kg^?1 K^?1 and in second thermal cycle is?45739.92 J kg^?1 K^?1 between temperature range of 298–573 K. As both mixtures are endothermic in nature in all cycles, it can be used as heat storage material.The average crystallite size of mixture 0.5Cu₂(PO₄)(OH); 3.5CuH(PO₄)₂·H₂O; 2NaHSO₄·H₂O and 0.5Cu₂(PO₄)(OH); 3.5CuH(PO₄)₂; 2Na₂SO₄ is ~47 and ~17.3 nm, respectively.     

Response of wheat (Triticum aestivum) and pearl-millet (Pennistum americanum) to zinc fertilizers on two soils

Responses of ZnSO₄, Zn₃ (PO₄)₂ · 4H₂O, ZnO, ZnNH₄PO₃ · 2H₂O and zincated superphosphate were studied on wheat (Triticum aestivum) and pearl-millet (Pennistem americanum) in Balsamand sand (Ustipsament) and Ladwa fine loam (Typic Camborthids). In Balsamand sand all Zn fertilizers increased wheat and pearl-milllet grain yield significantly over control but ZnNH₄ PO₄ · 2H₂O and zincated super were the best sources. Straw yield was also highest due to zincated super and ZnNH₄PO₄ · 2H₂O applications. Zinc sulphate was significantly inferior to zincated super and ZnNH₄PO₄ · 2H₂O. In Ladwa fine loam, all fertilizers gave significantly higher grain yield of wheat and pearl-millet than control except ZnO in pearl-millet. Highest yield in this soil was obtained by ZnSO₄ · 7H₂O followed by ZnNH₄ PO₄ · 2H₂O and then zincated super.In Balsamand sand, the Zn fertilizers significantly increased the Zn concentration and Zn uptake of wheat grain. In pearl-millet, only Zn uptake was increased significantly with Zn fertilizers. Zincated super gave highest Zn uptake.The concentration of P in wheat grain was increased by Zn fertilizers in Balsamand sand, and also in pearl-millet where zincated super and ZnNH₄PO₄ were most effective in increasing the P content.When Zn fertilizers were applied to preceding pearl-millet the effect on succeeding wheat crop were in the same order as direct application of Zn fertilizers. Zincated super was the best and ZnO worst with respect to wheat grain and straw yield and uptake of Zn and P.     

The transformation: Brushite → calcium monofluorophosphate under aqueous conditions

The reaction between CaHPO₄. 2H₂O and 10^?1 M solution of Na₂PO₃F have been studied in the pH range 7 to 5 at 25 °C. The formation of CaPO₃F · 2H₂O, rather than CaF₂ or Ca₅F (PO₄)₃ by initial hydrolysis and subsequent reaction with the F^? formed, appeared to occur. The value of ΔG for CaPO₃F · 2H₂O has been calculated as – 530.9 kcal mol^?1. A comparison is drawn to the exchange reactions reported here, and to the similar reactions reported to occur in calcium deficient apatite.     

不同介质中间硝基苯磺酸钠的电化学行为

研究了铜电极上间硝基苯磺酸钠在含有四丁基高氯酸铵（TBAP）电解质的质子惰性介质（DMF）、质子介质（H₂O）及混合介质（DMF/H₂O）中的电化学行为。结果表明：在质子惰性介质中,间硝基苯磺酸钠分步连续地被还原为ArNO^-₂·和［ArNO²］^2-·阴离子自由基;其中ArNO₂/ArNO^-₂·为扩散控制的单电子转移可逆氧化还原反应。在水溶液中,间硝基苯磺酸钠经历了ArNO₂/ArNO和ArNO/ArNHOH反应。而在混合溶剂中,由于DMF的存在阻碍了硝基的质子化进程,间硝基苯磺酸钠经历了ArNO₂/ArNO^-₂·和ArNO-2·/ArNHOH反应。通过量化计算进一步证实了上述实验结果。