关环复分解反应(RCM)及其催化剂研究进展

综述了近年来关环复分解 (RCM )反应及其催化剂的研究进展 ,对RCM反应发展以来被广泛应用的催化剂 ,如Schrock催化剂和Grubbs催化剂等进行了归纳和总结 ,讨论了RCM反应在全合成中的应用     

不对称催化氧化制备(S)-泮托拉唑

以(2S,3S)-N,N’-二苄基-酒石酸二酰胺和Ti(O-Pri)4形成的手性络合物为催化剂,枯烯过氧化氢为氧化剂,不对称催化氧化制备了(S)-泮托拉唑,转化率87%,纯化后的化学纯度>99.5%,光学纯度99.5%,硫醚含量<0.1%,砜含量<0.1%,其结构经1H NMR确证。     

影响面粉中铝含量测定因素分析

目的探讨了江苏省疾控[2009]97号文件附录A《面制品及海蜇中铝的测定方法》测定面制食品中铝含量。方法样品经干法消化后,在乙二胺-盐酸缓冲溶液中,三价铝在十六烷基三甲基溴化铵阳离子表面活性剂存在下,与铬天青S形成绿色三元体系,其吸光度与铝的含量在一定含量范围内成正比。结果样品消化液在定容30 min时测定结果接近中位值,方法线性系数r=0.999 7,相对标准偏差在3.3%~3.7%之间,样品回收率在88.9%~96.4%。结论该法操作简便,灵敏度高,适用于各实验室开展检测。     

Ab initio calculations on the ground and excited states of InI

Potential energy curves (PECs) of the ground and the low-lying excited states of the InI molecule are computed using the internally contracted multireference singles and doubles configuration interaction with the Davidson correction (ic-MR-CISD + Q) method based on the relativistic effective core potentials (RECPs). The spectroscopic constants are obtained, including the excitation energy (T _e), the equilibrium bond distance (R _e), the dipole moment (μ_e) and the vibrational constants (ω_e and ω_e). Finally, we predict the transition dipole moments, the radiative lifetimes, and the Franc-Condon factors for the transitions of A³Π₀+ ? X¹Σ₀ ⁺ and B³Π^l ? X¹Σ₀ ⁺,. The results reveal that A³Π₀+ and B³Π_l are long-lived states with the lifetimes being of the order of microseconds.     

基于回波平移序列的快速三维磁共振温度成像方法

高强度聚焦超声（HIFU）是一种无创的热消融疗法，为保证其安全性和有效性，需要一种精度高、速度快的测温方法在其治疗过程中对温度进行监控.基于质子共振频率位移（PRFS）的磁共振温度成像（MRT）对温度具有较高的灵敏度，且与温度具有良好的线性关系，因此常被用于引导HIFU治疗.然而在实际应用中，HIFU治疗的最大隐患在于可能造成表皮灼伤，并且灼伤区域可能与焦点区域相隔较远.因此MRT的监控范围十分重要.本文基于三维回波平移成像序列，结合可控混叠的空间并行成像技术，实现了时间分辨率为3 s的快速三维温度成像.为了验证该方法的精度，本文首先设计了仿体降温实验，利用光纤温度计验证回波平移序列测温的准确度和精确度.然后在室温条件下扫描离体猪肉组织，对比加速前后的MRT的测温精确度.在HIFU加热条件下扫描离体猪肉组织，对比加速前后的MRT的测温准确度.结果显示，本文提出的方法可以在3 s内完成三维温度精准测量，对于HIFU治疗的安全监控具有重要意义.     

Differential equation dynamical system based assessment model in GNSS interoperability

With the development of Global Navigation Satellite System (GNSS),the idea of GNSS interoperability is born and has become the focus of study in the field of satellite navigation.The popularity for GNSS to augment the interoperability with the existing ones necessitates the study of the assessment algorithm of this idea.In this paper,an assessment algorithm for interoperability comprehensive benefits based on the differential equation dynamical system is discussed.There are two important aspects in GNSS tha...     

Recoverable Mn~Ⅲ (salen) supported on diamine modified zirconium poly(styrene-isopropenyl phosphonate)-phosphate as an efficient catalyst for epoxidation of unfunctionalized olefins

Chiral Mn Ⅲ (salen) (Jacobsen’s catalyst) was axially immobilized onto a new type of organic polymer-inorganic hybrid materialzirconium poly(styrene-isopropenyl phosphonate)-phosphate(ZPS-IPPA) with different linkage lengths and evaluated as catalysts for the epoxidation of unfunctionalized olefins. The results demonstrated that the prepared catalysts exhibited moderate to good activity and enantioselectivity in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, the immobilized catalysts were relatively stable and could be conveniently separated from the reaction system by simple precipitation in hexane. Moreover, higher enantioselectivity was obtained with catalyst 2c than that of homogeneous counterpart catalyzed even after eight times. The excellent recycling of the catalyst was attributed to its structure feature of ZPS-IPPA which is different from either pure polystyrene or pure zirconium phosphates.     

PW11O39Co（Ⅱ）（H2O）5-的均相及异相体系可见光催化性能研究

以模型污染物罗丹明B（RhB）的光降解为探针,评估了Keggin型钴取代杂多阴离子PW₁₁O₃₉Co（Ⅱ）（H₂O）^5-（PW₁₁Co）及其异相体系PW₁₁Co/D301R的可见光催化活性,提出了光催化反应的机理,同时考察了催化剂用量、溶液酸度以及溶液中PW₁₁Co和RhB的相互作用对RhB可见光催化降解速率的影响。实验结果表明,PW₁₁Co均相体系及其异相体系PW₁₁Co/D301R对RhB的可见光降解均有较高的光催化活性,但与PW₁₁Co相比,PW₁₁Co/D301R的光催化活性更高。导致RhB降解的主要是羟基自由基。与PW₁₁Co均相体系相比,在PW₁₁Co/D₃₀₁R异相体系中由于PW₁₁Co与RhB的配位作用大为减弱,同时D301R对RhB具有富集作用,因而大大提高了RhB的光催化降解速率。     

中空纳米二氧化硅复合微球的制备及其对蛋白的亲和分离

利用水热法合成了中空巯基纳米二氧化硅微球(SiO₂-SH), 然后在其表面修饰亚氨基二乙酸基团(-IDA), 形成了中空SiO₂-SH/IDA双功能化纳米微球。利用该纳米微球表面的-SH和-IDA双功能团, 可以更多的吸附溶液中的Ni²⁺, 形成SiO₂-SH/IDA-Ni²⁺复合微球从而可以更好的分离以六聚组氨酸为标签的(His-tagged)蛋白。结果显示制备的样品对分离His-tagged蛋白具有广谱性, 并且具有较好的再生能力。     

Br-掺杂Bi2WO6的水热法合成及其可见光催化性能

以Bi（NO₃）₃·5H₂O和Na₂WO₄·2H₂O为主要原料,采用水热法合成了纯相Bi₂WO₆,并对其进行非金属离子Br^-掺杂改性。采用XRD、SEM、TEM、XPS、Raman、PL和DRS研究了Br^-掺杂对Bi₂WO₆的物相结构、形貌和可见光催化性能的影响。结果表明,Br^-掺杂可有效提高Bi₂WO₆的可见光催化性能,当掺杂量（物质的量百分数）为8%时,溴掺杂Bi₂WO₆的光催化性能最好,可见光照射40 min后,可降解96.73%的罗丹明-B,与未掺杂Bi₂WO₆相比,其降解率提高了36.32%。