氟表面活性剂C_8F_(17)SO_2N(C_2H_5)C_2H_4(OC_2H_4)的合成与性能

以全氟辛基磺酰氟为原料,与乙胺在异丙醚中加热反应制得N 乙基全氟辛基磺酰胺,再与2 氯乙醇在加热回流下反应得到N 乙基N 乙醇全氟辛基磺酰胺,随后在碱性条件,加热和带压下与环氧乙烷进行聚合反应,得到表面活性剂C8F17SO2N(C2H5)C2H4(OC2H4)nOH,n=8～9。该活性剂在质量浓度为0.05%时就可将表面张力降至19.2mN/m以下,具有良好的表面活性。运用IR,NMR,DSC,TG等技术对该表面活性剂进行了表征和研究。     

NaAlCl4/ZSM-5@γ-Al2O3核壳复盐催化剂的制备及其歧化性能

针对氯硅烷残留物的危害性和资源化利用,通过歧化反应将副产物制备成经济效益更高的二甲基二氯硅烷。由田菁胶为粘结剂,以γ-Al₂O₃为壳,对ZSM-5分子筛表面进行修饰,构筑ZSM-5@γ-Al₂O₃核壳载体;然后,通过高温浸渍负载法,将NaAlCl₄负载在ZSM-5@γ-Al₂O₃核壳载体表面。综合研究了不同Si/Al摩尔比的ZSM-5分子筛、不同NaAlCl₄负载比例和AlCl₃溶液浸渍时间对歧化制备反应二甲基二氯硅烷的影响。采用XRD、SEM、SEM-EDS、BET和FTIR对样品进行表征分析,结果表明,当温度为200℃,硅铝摩尔比为50,复盐NaAlCl₄比例为8wt%,AlCl₃浸渍时间为3 h时,催化剂活性达到最佳,产率为71.81%。通过NaAlCl₄复盐负载ZSM-5@γ-Al₂O_3...     

水热法制备(NH_4)_xWO_(3-y)和WO_3·1/3H_2O:反应温度对产物物相、微结构和光学性能的影响（英文）

本工作研究了水热法制备钨系氧化物过程中反应温度对产物物相、微结构和光学性能的影响。XRD结果表明100℃条件下制备的样品为纳米六方相铵钨青铜(NH4)xWO3-y。随着水热温度升高(140和180℃),部分六方相(NH4)xWO3-y逐步转变为正交相三氧化钨WO3·1/3H2O,形成两相共存产物。SEM和TEM分析证实(NH4)xWO3-y和WO3·1/3H2O粒子均为沿[001]方向(c轴)生长的短棒状单晶,随水热反应进行它们会通过取向融并(oriented attachment)方式进一步长大。结构分析同时证实,棒状晶的物相与其尺寸存在明显联系,纳米尺寸的棒状晶为六方(NH4)xWO3-y相,而微米尺寸的棒状晶为正交WO3·1/3H2O相。依据实验结果,提出了一种表面能控制的六方相(NH4)xWO3-y向正交相WO3·1/3H2O相转变机理。光学性能测量表明,100℃制备的六方相(NH4)xWO3-y样品可以很好的遮蔽近红外光(遮蔽率:74.5%),同时保持高可见光透过率(67.6%)。     

Li_2O-Al_2O_3-WO_3三元系中Al_2(WO_4)_3-Li_2WO_4和Al_2(WO_4)_3-Li_2O截面的相平衡研究

本文用 X 射线衍射和差热分析等方法研究了 Li_2O-Al_2O_3-WO_3三元系中 Al_2(WO_4)_3-Li_2WO_4和 Al_2(WO_4)_3-Li_2O 截面相平衡关系。在 Al_2(WO_4)_3-Li_2WO_4赝二元系中生成一新化合物 Al_2(WO_4)_3·Li_2WO_4,该化合物在883±3℃由包晶反应生成。它与 Li_2WO_4形成共晶体系,共晶温度为680±3℃,共晶点组成为90mol%Li_2WO_4。在 Al_2(WO_4)_3-Li_2O 截面中由包晶反应形成一新化合物 Al_2(WO_4)_3·4Li_2O,其包晶反应温度为720±3℃。在这一截面中,在组份45mol%Li_2O 处存在一化合物,该化合物确定为 Al_2(WO_4)_3·Li_2WO_4。Al_2(WO_4)3·4Li_2O 与 Al_2(WO_4)_3·Li_2WO_4形成共晶体系,其共晶温度为682±3℃,共晶点组成约为70mol%Li_2O。     

固相制备Li_(4-3x)Eu_x(WO_4)_2微晶及发光性能

采用固相法制备了Li_(4-3x)Eu_x(WO_4)_2系列红色荧光粉。通过荧光分析(FL)、扫描电镜(SEM)和X射线衍射(XRD)对所得粉体的发光性能、颗粒大小及形貌和物相进行表征分析。XRD分析表明制备的Li_(4-3x)Eu_x(WO_4)_2微晶均为白钨矿四方结构;SEM结果显示随着x的增大,Li_(4-3x)Eu_x(WO_4)_2微晶的晶粒尺寸相应增大,在0.1~0.5μm之间变化。荧光分析结果表明该荧光粉可被近紫外(395nm)光有效激发,最大发射波长位于614nm,获得纯正的红光。随着x的增大,样品中Eu~(3+)的593nm和614nm处两个特征发射峰的强度先增大后减小,当x=1.0时达到最大。     

(C_(4n)H_(8n+1)NH_3)_2CuCl_4层状钙钛矿结构杂化材料的制备与性能

本文将不同碳链长度的有机胺与氯化铜复合,制备了一系列含直链烷基胺的杂化钙钛矿结构晶体材料,并对其结构性能进行了研究,发现可以通过改变杂化材料中烷基链长度对材料的热稳定性、溶液加工性、光学性质进行调控。系统研究表明,随着杂化材料中碳原子数的增加(4→8→12),杂化材料的溶液加工性提高,烷基链间相互作用力增强,有机、无机组分间氢键强度随之增大,杂化材料的热稳定性提高。     

Ni-Mo-Al_2O_3催化剂覆碳改性对其加氢脱硫性能的影响

在催化剂制备的不同阶段引入碳物质,制备3种覆碳改性的NiMo-Al_2O_3加氢脱硫催化剂,采用低温氮静态容量吸附-脱附法、X射线衍射、H_2程序升温还原和高分辨透射电子显微镜对3种催化剂进行表征,并考察催化剂的加氢脱硫性能。结果表明:引入碳物质能够提高催化剂的加氢脱硫活性;采用前覆碳法即在载体上负载活性组分前引入碳前躯物,或采用共浸渍法即将活性组分与碳前躯物共同浸渍到载体上制得的催化剂,都能够增加八面体Mo物种的数量;采用共浸渍法制得催化剂活性组分分散性良好,MoS_2纳米颗粒堆垛层数多,其脱硫率比未覆碳改性催化剂的高6.8%;采用前覆碳法制得催化剂的金属分散性良好,其脱硫率比未覆碳改性催化剂的高5.1%;与未覆碳改性的催化剂相比,采用后覆碳法即在已负载活性组分的Ni-Mo-Al_2O_3催化剂上引入碳前躯物制得催化剂的脱硫率提高程度不大。     

Ca_(0.5)Zr_2(PO_4)_3掺杂CaO的缺陷模型

研究了在Ｃａ０．５Ｚｒ２（ＰＯ４）３组成中引入ＣａＯ后的缺陷反应。少量的Ｃａ２＋离子进入空隙ＭⅠ位增大了ｃ轴尺寸，ａ轴略有减小。Ｃａ２＋离子超过１．５个后，进入ＭⅠ位，造成ａ增大而ｃ值略有降低。     

助催化剂和己烯对MgCl2/SiO2复合载体型Ziegler-Natta催化剂催化乙烯聚合的影响

采用MgCl2/SiO2复合载体制备了一种乙烯聚合催化剂。考察了烷基铝种类、铝钛配比和1-己烯加入量对乙烯聚合性能的影响,并利用激光粒度分布仪、扫描电镜(SEM)和X射线衍射(XRD)对催化剂的形态和物性进行了表征,用差示扫描量热(DSC)、红外光谱(FT-IR)和凝胶渗透色谱(GPC)对聚合产物进行了分析。结果表明,催化剂保持了良好的颗粒形态和均匀程度;三异丁基铝(Al(iBu)3)为助催化剂所得的聚合活性和共聚能力高于三乙基铝(AlEt3)为助催化剂的催化体系。Al(iBu)3活化体系的活性中心分布与AlEt3活化体系有显著的差别。     

La助剂对甲醇水蒸气转化制氢CuO—ZnO／Al2O3催化剂性能的影响

本文介绍La助剂甲醇转化制氢催化剂的制备。性能评价试验，在提高性能、稳定性等方面取得了成果，显示出较好的工业应用前景。     

Precise Pore Engineering of fcu-Type Y-MOFs for One-Step C2H4 Purification from Ternary C2H6/C2H4/C2H2 Mixtures

The purification of C₂H₄ from C₂H₆/C₂H₄/C₂H₂ mixtures is of great significance in the chemical industry for C₂H₄ production but remains a daunting task. Guided by powerful reticular chemistry principles, herein a systematic study is carried out to engineer pore dimensions and pore functionality of fcu-type Y-based metal–organic frameworks (Y-MOFs) through the construction of a series of eight new structures using linear dicarboxylate linkers with different length and functional groups. This study illustrates how delicate changes in pore size and pore surface chemistry can effectively influence the adsorption preference of C₂H₆, C₂H₄, and C₂H₂ by the MOFs. Importantly, clear relations between pore size/pore surface polarity and C₂ adsorption selectivities of this series of MOFs are established. In particular, HIAM-326 built on a linker decorated with trifluoromethoxy group shows notably preferential adsorption of C₂H₆ and C₂H₂ over C₂H₄, with balanced C₂H₂/C₂H₄ and C₂H₆/C₂H₄ selectivities. This endows the compound with the capability of one-step purification of C₂H₄ from C₂H₆/C₂H₄/C₂H₂ ternary mixtures, which is validated by breakthrough measurements where high purity C₂H₄ (99.9%+) can be obtained directly from the separation column. Its adsorption thermodynamics and underlying selective adsorption mechanisms are further revealed by ab initio calculations.     

孔径分布对多孔镍孔体积分形维数的影响

用压汞法对用粉末冶金法制备的多孔镍试件进行了测试,得到了多孔镍试件的孔隙率及孔径分布曲线,并以Menger海绵体模型为基础,根据压汞实验数据确定了多孔镍试件的孔体积分形维数,发现多孔镍的孔隙结构具有明显的分形特征,分形维数在2.8～3.0之间.孔径分布范围越宽、平均孔径越大,孔体积分形维数越大.多孔镍的孔体积分形维数在一定程度上反映了多孔镍孔隙结构的均匀性及填充能力.     

钨酸钠和次磷酸钠浓度对脉冲电镀CeO2-SiO2/Ni-W-P纳米复合薄膜组织及性能的影响

通过Ni、W、P与CeO₂和SiO₂纳米颗粒的脉冲共沉积,在碳钢表面制备了CeO₂-SiO₂/Ni-W-P纳米复合薄膜,主要研究了电解液中钨酸钠和次磷酸钠浓度对纳米复合薄膜组织及性能的影响,采用化学组成、沉积速率、显微硬度和表面形貌进行表征。结果表明,当钨酸钠和次磷酸钠浓度分别为100和4 g/L时,纳米复合薄膜的沉积速率和显微硬度较高,分别为25.03 μm/h和HV649。增加钨酸钠浓度,纳米复合薄膜晶粒得到细化。当钨酸钠浓度提高到160 g/L时,基质金属晶粒轮廓清晰,细小而均匀,呈规则的圆球型,CeO₂、SiO₂纳米颗粒均匀弥散分布在Ni-W-P基质金属中。次磷酸钠浓度的增加对纳米复合薄膜的表面形貌影响较小,但会明显降低显微硬度。     

Computations on Metallofullerenes Derivatized during Extraction: La@C80-C6H3Cl2 and La@C82-C6H3Cl2

Recently, an extraction of la metallofullerenes from soot using 1,2,4-trichlorobenzene has been reported for La@C₈₀ and La@C₈₂. In both cases, the cages were derivatized by the solvent (forming La@C₈₀-C₆H₃Cl₂ and La@C₈₂-C₆H₃Cl₂) and the following X-ray analysis disclosed rather unexpected cages: C₈₀(C _2v ;3) and C₈₂(C _3v ;7). In order to explain the challenging observations, a two-step computational treatment is presented. The first step deals with the high-temperature gas-phase formation of the underivatized endohedrals while the second step models the reaction with the solvent. The Gibbs free energies were evaluated for representative temperatures and the computational scheme was able to confirm high relative populations for the observed derivatized cages.     

氟化物对CaO-Al_2O_3-SiO_2系玻璃析晶行为的影响

采用DTA、XRD、SEM等现代测试分析手段研究了晶核剂CaF2 对CaO Al2 O3 SiO2 系玻璃析晶行为的影响。结果表明 ,晶核剂CaF2 能有效地促进玻璃的整体析晶 ,在一定热处理制度下 ,可制备出晶粒尺寸为0 .1～ 0 .2 μm的白色微晶陶瓷 ,主晶相为透辉石和硅灰石。随着CaF2 含量的增加 ,透辉石型晶相增多 ,硅灰石型晶相减少。     

A thermal dehydration study of WO3·2H2O

Step-wise thermal dehydration of WO₃·2H₂O has been investigated and the various hydrated tungsten trioxide phases characterized. A cubic phase of tungsten trioxide with 0·36 moles of water is obtained by heating WO₃·2H₂O to 498 K.     

Effect of C6H14N2O7 and reaction temperature on sensing properties of hierarchical WO3 for H2S sensor

In this study, WO₃ nanoparticles with hierarchical structures are prepared by a simple hydrothermal method using diammonium hydrogen citrate (C₆H₁₄N₂O₇) as an additive, and the effects of reaction temperature and addition of C₆H₁₄N₂O₇ on their morphology are investigated in detail. The physical properties and morphology of the prepared WO₃ materials are analyzed by scanning electron microscopy, X-ray diffraction , transmission electron microscopy, and Brunauer–Emmett–Teller method, and a possible growth mechanism is proposed. The results show that C₆H₁₄N₂O₇ is adsorbed on the edges of the nanosheets and inhibits their anisotropic growth. In addition, based on this material, sensors are self-assembled for detecting the decomposition products of SF₆, and the gas-sensitive properties of the material are investigated. The experimental results show that the sensors based on WO₃ with hierarchical structures are highly sensitive to H₂S and exhibit a low operating temperature. This indicates that such sensors can be effectively used to detect the main decomposition products of SF₆.

     

TiO_2-Al_2O_3负载型催化剂的制备及其光催化性能

以钛酸四丁酯和氢氧化钠为反应物,采用两步水热法制备TiO2纳米线,并将其原位负载于Al2O3载体上,研究它们对甲基橙的光催化降解性能。结果表明,锐钛矿相TiO2主要呈纳米线和八面体状负载在Al2O3载体上,当TiO2负载质量分数为30%,焙烧温度为400℃,催化剂用量为1.332 0 g/L时,TiO2-Al2O3负载型催化剂光催化降解甲基橙的性能最佳,光照5 h后,甲基橙在紫外和太阳光下的降解率分别达到58.9%和55.6%。相同实验条件下,TiO2-Al2O3负载型催化剂对甲基橙的降解率比单纯TiO2提高了35.1%。     

溶液燃烧法制备Ni-Al2O3催化剂用于CO2-CH4重整研究

采用溶液燃烧法制备了Ni含量为2wt%、4wt%、6wt%、8wt%和10wt%系列催化剂, 并对反应前后催化剂进行N₂吸附-脱附、XRD、H₂-TPR、TPH、Raman、TEM和TG-DTG等表征。与等体积浸渍法(以溶液燃烧法制备的Al₂O₃为载体)制备的催化剂相比, 溶液燃烧法制备的催化剂具有较大的比表面积, 孔径分布可分为2~4.5 nm和4.5~10 nm两段, 属典型的多级孔结构; NiO高度分散在载体上, 与载体具有较强的相互作用, 这种相互作用有利于提高催化剂的稳定性。催化剂210 h稳定性试验表明, 溶液燃烧法制备的Ni含量为8wt%试样的CH₄转化率维持在90%左右, 失活速率仅为0.035%/h, 优于浸渍法制备的相同Ni含量催化剂。     

Preparation and stability of nanocrystalline (C6H5C2H4NH3)2PbI4-doped PMMA films

Preparation and stability of nanocrystalline (C₆H₅C₂H₄NH₃)₂PbI₄-doped PMMA films were investigated. By using spin-coating and subsequent annealing technique, nanometer-sized (C₆H₅C₂H₄NH₃)₂PbI₄ precipitates were successfully formed into a PMMA matrix. These films showed clear exciton absorption and free exciton emission at room temperature. Comparing with (C₆H₅C₂H₄NH₃)₂PbI₄ film, marked improvement of thermal- and photo-stability was observed for nanocrystalline (C₆H₅C₂H₄NH₃)₂PbI₄-doped PMMA films. The thermal-stability of these films correlates with the decomposition of the organic part. As for photo-stability, photo-irradiation induced oxidation is one of the possible reasons for the degradation of the films.