MgO－B_2O_3－MgCl_2－H_2O体系与盐酸滴定反应的研究

ＭｇＯ－Ｂ２Ｏ３－ＨｇＣｌ２－Ｈ２Ｏ是含硼盐湖日晒浓缩盐卤的典型体系，它与盐酸反应生成硼酸，是从天然浓缩盐卤中制取硼酸的工艺基础，以量热滴定法和ｐＨ滴定法研究该反应，结果表明，析出硼酸的反应分两步进行；合成盐卤中硼酸盐可以用ＭｇＢ２ｎＯ（３ｎ＋１）（ｎ＝１，２，３）综合统计形式来表示；天然浓缩盐卤中硼酸盐可以用四硼酸镁的统计形式进行表示．     

盐卤硼酸盐化学ⅩⅩⅥ. MgO·2B2O3－18%MgCl2－H2O产过饱和溶液结晶动力学研究

ＭｇＯ，２Ｂ２Ｏ３－１８％ＭｇＣｌ２－Ｈ２Ｏ过饱和溶液于２０℃恒温静置，其结晶过程分为两个阶段，第一阶段结晶析出三方硼镁石（ＭｇＯ，３Ｂ２Ｏ３，７．５Ｈ２Ｏ）。第二阶段析出章氏硼镁（ＭｇＯ．２Ｂ２Ｏ３．９Ｈ２Ｏ），未得到多水硼镁石和库水硼镁石，探讨了两种析出固相的结晶机理并拟事出结晶动力学方程，结果表明，两个种固相结晶机理场为多核表面反应控制生长。     

MgB4O7－MgSO4－MgCl2－H2O及次级体系298.15K时稀释热、热容和表观摩尔焓的研究

本文研究了含硼四元水盐体系ＭｇＢ４Ｏ７－ＭｇＳＯ４－ＭｇＣｌ２－Ｈ２Ｏ及次级体系ＭｇＢ４Ｏ７－ＭｇＳＯ４－Ｈ２Ｏ在２９８．１５Ｋ时不同离子强度下的稀释热和热容，产将Ｄｅｂｙｅ－Ｈｕｃｋｅｌ极限公式应用到多元电解质稀溶液中，获得从高子强度到低离子强度Ｉ为１９－０．０００１范围内的相对表观摩尔焓。     

Mn－Ag／γ－Al_2O_3催化剂中氧的性能

本文运用ＴＰＲ、ＴＰＤ－ＭＳ、ＸＲＤ等技术研究了Ｍｎ－Ａｇ／γ－Ａｌ_２Ｏ_３催化剂的还原性能和再氧化能力．结果表明，Ｍｎ－Ａｇ／γ－Ａｌ_２Ｏ_３中银物相由Ａｇ￣０和Ａｇ_２Ｏ组成，锰物相由β－ＭｎＯ_２和Ｍｎ２Ｏ_３组成．Ｍｎ／γ－Ａｌ_２Ｏ_３催化剂的ＴＰＲ有二个还原峰，分别是ＭｎＯ_２和Ｍｎ_２Ｏ_３的还原．Ａｇ促使ＭｎＯ_２和Ｍｎ_２Ｏ_３的还原明显向低温方向移动，而且ＭｎＯ_２和Ｍｎ_２Ｏ_３的还原峰融合成一个还原峰．Ｍｎ－Ａｇ／γ－Ａｌ_２Ｏ_３的ＴＰＤ有三个脱氧峰，随着Ａｇ含量增加，峰Ⅰ向高温方向移动，Ｍｎ￣（４＋）２ｐ３／２的电子结合能增加，并且催化剂的再氧化能力增强．催化剂ＣＯ的氧化活性与催化剂的再氧化能力有很好的对应关系．     

六核配合物[Mn6O2(O2CPh)10(py)4]·MeCN的合成及结构

将［Ｍｎ３Ｏ（Ｏ２ＣＰｈ）６（ｐｙ）２（Ｈ２Ｏ）］·０．５ＭｅＣＮ、水杨醛缩邻氨基酚和三乙胺在乙腈溶液中反应，合成了六核锰配合物。经Ｘ射线单晶结构分析确定该配合物晶体的化学结构式为［Ｍｎ６Ｏ２（Ｏ２ＣＰｈ）１０（ｐｙ）４］·ＭｅＣＮ。结构中含有一个［Ｍｎ６Ｏ２］１０＋核，可看成是两个［Ｍｎ４（μ４－Ｏ）］四面体共一条边，每个四面体的中心是一个μ４－Ｏ２－离子。晶体属单斜晶系，Ｐ２１／ａ空间群，晶胞参数ａ＝２．０５７２ｎｍ，ｂ＝１．８５２０ｎｍ，ｃ＝２．５３７５ｎｍ，β＝１１１．８２°，Ｖ＝８．９７５ｎｍ３，Ｚ＝４，最终偏差因子Ｒ＝０．０６３２，Ｒｗ＝０．０５９５。     

流动注射—原子吸收法测定药物制剂中的维生素B6

１引言在弱酸性介质中，新生态ＭｎＯ２与维生素Ｂ６（ＶＢ６）发生反应，通过ＦＩＡ－ＡＡＳ测定反应产物Ｍｎ２＋，建立了测定ＶＢ６含量的新方法。方法具有简便、快速、重现性好等优点，用于实际样品的测定，结果与药典法一致。２实验部分２．１仪器与试剂ＧＦＵ－２０２型原子吸收分光光度计；ＩＦＩＳ－Ｂ型智能流动注射进样器；Ｍｎ２＋标准溶液（１ｇ／Ｌ）；ＶＢ６标准溶液（１ｇ／Ｌ）；新制ＭｎＯ２＋：在０．２５％ＫＭｎＯ４溶液中逐滴加入０．５％ＭｎＳＯ４（其中含硫酸１ｍｏｌ／Ｌ）至红色完全消失。新制得的ＭｎＯ２保存在…     

1,12－烷基二胺－Na2O－SiO2－Al2O3－H2O系统中ZSM-11沸石的合成及其鉴定

以硅溶胶为硅源，在０．３０１，１２－烷基二胺－ＸＮａ２Ｏ－ＹＡｌ２Ｏ３－ＳｉＯ２－ＺＨ２Ｏ体系中，研究ＺＳＭ－１１沸石于１６０～２００℃之间的水热结晶。用ＸＲＤ鉴定产物，合成纯组ＺＳＭ－１１的反庆物配比是Ｘ＝０．０５；Ｙ＝０－０．０１１；Ｚ＝＝４０。其反应温度为１６０～１８０℃。加入ＺＳＭ－１１晶种或添加ＮａＦ可加快结晶速率，导致ＺＸＳ－１１柱状单晶的生成。该单晶的最大尺寸可达２０×２０×６０μｍ     

Mn—Ag／r—Al2O3催化剂中氧的性能

本文运用ＴＰＲ、ＴＰＤ－ＭＳ、ＸＲＤ等技术研究了Ｍｎ－Ａｇ／ｒ－Ａｌ２Ｏ３催化剂的还原性能和再氧化能力。结果表明，Ｍｎ－Ａｇ／ｒ－Ａｌ２Ｏ３中银物相由Ａｇ＾０和Ａｇ２Ｏ组成，锰物相由β－ＭｎＯ２和Ｍｎ２Ｏ３组成。Ｍｎ／ｒ－Ａｌ２Ｏ３催化剂的ＴＰＲ有二个还原峰，分别是ＭｎＯ２和Ｍｎ２Ｏ３的还原。Ａｇ促使ＭｎＯ２和Ｍｎ２Ｏ３的朱明显向低温方向移动，而且ＭｎＯ２和Ｍｎ２Ｏ３的还原峰融合成一个还原峰。Ｍｎ     

金属键有机化合物的研究──非对称型η~5－取代环戊二烯基三羰基钼（钨）金属单键化合物的合成及表征

通过η５－Ｒ~１Ｃ＿５Ｈ＿４（ＣＯ）＿３ＭＮａ与η~５－Ｒ~２Ｃ＿５Ｈ＿４（ＣＯ）＿３ＭＮａ（Ｍ＝Ｍｏ，Ｗ）以及η~５－Ｒ~１Ｃ＿５Ｈ＿４（ＣＯ）＿３ＭｏＮａ与η~５－Ｒ~２Ｃ＿５Ｈ＿４（ＣＯ）＿３ＷＮａ在Ｆｅ＿２（ＳＯ＿４）＿３醋酸水溶液作用下的交叉氧化偶联反应，合成了７个新的非对称型金属单键化合物η~５－Ｒ~１Ｃ＿５Ｈ＿４（ＣＯ）－３Ｍｏ─Ｍｏ（ＣＯ）＿３Ｃ＿５Ｈ＿４Ｒ~２－η~５（Ｒ~１，Ｒ~２：Ｃ（Ｏ）Ｍｅ，ＣＯ２Ｅｔ），η５－Ｒ１Ｃ５Ｎ４（ＣＯ）３Ｗ─Ｗ（ＣＯ）３Ｃ５Ｈ４Ｒ２－η５（Ｒ１，Ｒ２：Ｃ（Ｏ）Ｍｅ，ＣＯ２Ｅｔ；Ｈ，ＣＯ２Ｅｔ）和η５－Ｒ１Ｃ５Ｈ４（ＣＯ）３Ｍｏ─Ｗ（ＣＯ）３Ｃ５Ｈ４Ｒ２－η５（Ｒ１，Ｒ２：Ｃ（Ｏ）Ｍｅ，Ｈ；Ｅｔ，Ｃ（Ｏ）Ｍｅ；Ｃ（Ｏ）Ｍｅ，ｎ－Ｂｕ；ＣＯ２Ｍｅ，ｎ－Ｂｕ）．用Ｃ／Ｎ分析、ＩＲ、１ＨＮＭＲ和ＭＳ表征了它们的结构，并对该氧化偶联反应的特点进行了讨论．     

CONVERSION OF KETONES INTO1，1－DISUBSTITUTED－2，3，3－TRIFLUORO－2－PROPEN －1－OLSWITH1，1－DIBROMO－1，2，2，2－TETRLUORO ETHANE／MAGNESIUM REAGENT

ＣＯＮＶＥＲＳＩＯＮ　ＯＦ　ＫＥＴＯＮＥＳ　ＩＮＴＯ１，１－ＤＩＳＵＢＳＴＩＴＵＴＥＤ－２，３，３－ＴＲＩＦＬＵＯＲＯ－２－ＰＲＯＰＥＮ　－１－ＯＬＳＷＩＴＨ１，１－ＤＩＢＲＯＭＯ－１，２，２，２－ＴＥＴＲＬＵＯＲＯ　ＥＴＨＡＮＥ／ＭＡＧＮＥＳＩＵＭ...     

Tunneled Intergrowth Structures in the Ga2O3–In2O3–SnO2 System

The structures of several Ga₂O₃–In₂O₃–SnO₂ phases were investigated using high-resolution electron microscopy, X-ray diffraction, and Rietveld analysis of time-of-flight neutron diffraction data. The phases, expressed as Ga_4−4xIn_4xSn_n−4O_2n−2 (n=6 and 7–17, odd), are intergrowths between the β-gallia structure of (Ga,In)₂O₃ and the rutile structure of SnO₂. Samples prepared with n≥9 crystallize in C2/m and are isostructural with intergrowths in the Ga₂O₃–TiO₂ system. Samples prepared with n=6 and n=7 are members of an alternative intergrowth series that crystallizes in P2/m. Both intergrowth series are similar in that their members possess 1-D tunnels along the b axis. The difference between the two series is described in terms of different crystallographic shear plane operations (CSP) on the parent rutile structure.     

Oxygen deficiency and phase transitions in SrCo1– x – y Fe x Cr y O3–δ ( x =0.10–0.40, y =0–0.05)

Oxygen-deficient phases based on perovskite-like strontium cobaltites-ferrites are promising mixed conductors for high-temperature electrochemical applications. The p(O₂)-T-δ diagrams for the oxide systems SrCo_{1– x – y} Fe _x Cr _y O_{3– δ} (x=0.10–0.40; y=0–0.05) were studied at 500–1000 °C in the oxygen pressure range from 10^–5 to 0.21 atm using the coulometric titration technique and thermogravimetric analysis. Stability limits of the cubic perovskite phases having a high oxygen ionic conductivity were evaluated as functions of temperature, oxygen partial pressure and oxygen nonstoichiometry. It was found that doping with chromium and increasing the iron content in SrCo(Fe,Cr)O_{3– δ} both lead to a considerable enlargement of the cubic perovskite phase existence domain towards lower temperatures and reduced oxygen pressures. Electronic Publication     

g-C_3N_4/CaTi_2O_5复合材料制备及其光催化性能

利用类石墨氮化碳(g-C_3N_4)和亚稳相钙钛氧化物(CaTi_2O_5)固相法制备C_3N_4/CaTi_2O_5复合材料。利用X射线衍射(XRD)、金相显微镜、扫描电子显微镜(SEM)及附带能谱分析仪(EDS)和N2吸附-脱附对样品的显微结构和比表面积进行检测分析,并用紫外-可见吸收光度计(UV-Vis)测试了样品的光吸收性能,研究C_3N_4与CaTi_2O_5物质的量之比(nC_3N_4/nCaTi_2O_5)对C_3N_4/CaTi_2O_5复合样品的物相结构和微观形貌的影响,同时考察C_3N_4/CaTi_2O_5复合样品在可见光照射下光催化降解罗丹明染料效果。实验结果表明:相比纯C_3N_4和CaTi_2O_5样品,C_3N_4/CaTi_2O_5复合样品在可见光下具有较高的光催化性能,随着nC_3N_4/nCaTi_2O_5增加,样品的光催化降解率随之增加而后降低,当nC_3N_4/nCaTi_2O_5=1∶1时,样品的光催化降解率达到最大值99.5%,并且循环重复利用5次后,样品的光催化剂降解率仍几乎保持不变。复合样品光催化性能提高主要归因于复合能级结构有效地抑制了电子和空穴复合所致。     

g-C3N4/CaTi2O5复合材料制备及其光催化性能

利用类石墨氮化碳（g-C₃N₄）和亚稳相钙钛氧化物（CaTi₂O₅）固相法制备C₃N₄/CaTi₂O₅复合材料。利用X射线衍射（XRD）、金相显微镜、扫描电子显微镜（SEM）及附带能谱分析仪（EDS）和N₂吸附-脱附对样品的显微结构和比表面积进行检测分析,并用紫外-可见吸收光度计（UV-Vis）测试了样品的光吸收性能,研究C₃N₄与CaTi₂O₅物质的量之比（n_C3N4/nCaTi₂O₅）对C₃N₄/CaTi₂O₅复合样品的物相结构和微观形貌的影响,同时考察C₃N₄/CaTi₂O₅复合样品在可见光照射下光催化降解罗丹明染料效果。实验结果表明：相比纯C₃N₄和CaTi₂O₅样品,C₃N₄/CaTi₂O₅复合样品在可见光下具有较高的光催化性能,随着n_C3N4/nCaTi₂O₅增加,样品的光催化降解率随之增加而后降低,当n_C3N4/nCaTi₂O₅=1：1时,样品的光催化降解率达到最大值99.5%,并且循环重复利用5次后,样品的光催化剂降解率仍几乎保持不变。复合样品光催化性能提高主要归因于复合能级结构有效地抑制了电子和空穴复合所致。     

锶助剂对铂锡催化剂正丁烷脱氢催化性能的影响

负载型ＰｔＳｎ／Ａｌ２Ｏ３催化剂已广泛地应用于工业生产中［１］，人们正尝试着添加不同助剂以改变催化剂的反应性能。文献的工作主要集中在研究铂锡催化剂中添加助剂对载体表面酸性的调变作用。在烃类重整催化剂中，加入氟、氯等元素可增强载体的表面酸性［２］，提高...     

以四乙基氢氧化铵为模板并通过转晶法合成高硅铝比的SSZ⁃13沸石分子筛

使用四乙基氢氧化铵为有机模板剂,以低硅铝比(nSiO2/nAl2O3)的Y分子筛为铝源,通过转晶法制备结晶度良好的SSZ?13沸石分子筛。从凝胶配比方面考察了不同原料组成对分子筛合成的影响,并通过X射线衍射(XRD)、扫描电子显微镜(SEM)及电感耦合等离子体(ICP)表征水热反应过程中的物相、形貌、硅铝比等变化,揭示分子筛合成过程。氨选择性催化还原(NH3?SCR)反应显示该分子筛具有优异的催化活性,为其工业上的广泛应用提供了可能性。     

Random-Walk Aggregation Phenomena in Solid Bimodal Liquid Dispersions: Transition to Nondeterminism from Si3N4to Si3N4+ Al2O3Aqueous Systems

This paper, which is based on another recent work, (Mezzasalma, S. A.,Phys. Rev. E55(4), (1997)) deals with experiments and theory concerning an aqueous dispersed system formed from silicon nitride (Si₃N₄), alumina (Al₂O₃), and mixed silicon nitride + alumina (Si₃N₄+ Al₂O₃) solid agglomerates. From titration data applied to a thermodynamic equilibrium condition, the minimum number of each agglomerate species and their maximal average dimensions have been derived as functions of the aqueous solution pH. These parameters are of the order of, respectively, (1–2) μm for Si₃N₄and Al₂O₃agglomerates and (20–50) μm for the mixed agglomerates. The numbers of solid particles of all species are poorly correlated with changes in pH of the liquid phase. This behavior has been interpreted as intrinsically related to the complexity of the system which, due to the many interactions among the different species, probably becomes nondeterministic. In order to describe such behavior a probabilistic approach has been developed. The probability of finding a given solid agglomerate number within a scatter band varies with the suspension pH. Furthermore, the scatter band amplitude becomes negligible near the isoelectric point. Accordingly, only the numbers of aggregates derived in the neighborhood of the isoelectric point are predictable.     

过渡金属改性的Pd/TS-1催化氢、氧直接合成H_2O_2的性能

利用等体积浸渍法制备了M-Pd/TS-1(M=Ce,La,Pt,Fe,Co,Ni,Cr,Mn,Zn,Cd,Cu)系列催化剂,并将制得的催化剂用于常压下氢、氧直接合成过氧化氢的反应。考察了M的类型及负载量对M-Pd/TS-1催化剂催化性能的影响。结果表明,M选Ce时,催化剂的性能最好。Ce的最佳掺入量,n_(Ce)/(n_(Ce)+n_(Pd))=0.5%。对Ce改性与未改性的催化剂进行了TEM及静态化学吸附分析,结果表明,掺入Ce可使Pd在TS-1分子筛表面的粒度及分散度得到改善。考察了n_(O_2)/n_(H_2)比,气体流量,反应时间等反应条件对H_2转化率、H_2O_2选择性及收率的影响。在相对优化的工艺条件下,即n_(O_2)/n_(H_2)=3,气体流量为25 mL·min~(-1),反应时间为3 h时,H_2O_2,的收率可达到25.7%,TOF值为18.7 mol·mol~(-1)·h~(-1),此时溶液中H_2O_2的质量百分数为0.8%。     

Catalytic Performance of Re/Ga2O3/WO3/ZrO2 Catalyst for n-Hexane Isomerization

A series of Re/Ga₂O₃/WO₃/ZrO₂ catalysts were prepared by the impregnation method. The crystalline structure, redox, and acid site distribution of the catalysts were characterized by X-ray powder diffraction, temperature-programmed reduction of H₂, and temperature-programmed desorption of NH₃. Their catalytic performance for n-hexane isomerization was studied. The results showed that the addition of Re greatly affected the redox properties and the acid site distribution of the catalysts. Owing to the presence of Re, n-hexane isomerization was catalyzed by metal and acid sites, and thus the conversion of n-hexane and the selectivity for 2,2-dimethylbutane were significantly increased. Under the conditions of 195 °C, 1.0 MPa, LHSV = 1.0 h⁻¹, and n(H₂)/n(C₆) = 2.0, the conversion of n-hexane over 1.0%Re/1.0%Ga₂O₃/WO₃/ZrO₂ is 84.8%, and the selectivities for 2,2-dimethylbutane, i-hexane, and cracking products (C_5-) are 20%, 97.7%, and 2.1%, respectively. The catalyst is stable during 150 h operation.