在N_2中[V_nCr_(3-n)(μ_3-O)(μ-O_2CCH_3)_6(THF)_3]X[n=0-3,X=Cl~-,ClO_4~-,(VO_5)_(0.5)~-]及[V_nFe_(3-n)(μ_3O)(μ-O_2CCH_3)_6(THF)_3]X(n=0-3,X=Cl~-)反应行为的原位红外光谱研究

利用原位红外光谱研究标题化合物在N2 中的反应行为。发现它们在不同温度下能使乙酸分别转化为丙酮和甲烷。它们对乙酸的丙酮化反应活性顺序 :[V3OAT]>[VFe2 OAT],[V2 CrOAT]>[Fe3OAT],[VCr2 OAT]>[Cr3OAT][OAT =(μ3 O) (μ O2 CCH3) 6(THF) 3]。它们对乙酸的甲烷化反应活性顺序 :[Cr3OAT]>[VCr2 OAT],[V2 CrOAT]>[V3OAT]>[VFe2 OAT],[FeO3OAT]。对乙酸的丙酮化反应活性[Fe3OAT]明显低于 [Fe3OAH][OAH =(μ3 O) (μ O2 CCH3) 6(H2 O) 3]。对乙酸的甲烷化反应活性 [Cr3OAT]也明显低于 [CrOAH]。并对上述 [Fe3OAT],[Cr3OAT]与 [Fe3OAH],[Cr3OAH]之间差异进行了讨论。     

在N2中［VnCr3－n(μ3-O)（μ-O2CCH3）6（THF）3］X［n＝0－3，X＝Cl－，ClO－4，（VO5）－0.5］及［VnFe3－n（μ3-O）（μ-O2CCH3）6（THF）3］X（n＝0－3，X＝Cl－）反应行为的原位红外光谱研究

利用原位红外光谱研究标题化合物在N2中的反应行为。发现它们在不同温度下能使乙酸分别转化为丙酮和甲烷。它们对乙酸的丙酮化反应活性顺序：［V3OAT］＞［VFe2OAT］，［V2CrOAT］＞［Fe3OAT］，［VCr2OAT］＞［Cr3OAT］［OAT＝（μ3-O）（μ-O2CCH3）6（THF）3］。它们对乙酸的甲烷化反应活性顺序：［Cr3OAT］＞［VCr2OAT］，［V2CrOAT］＞［V3OAT］＞［VFe2OAT］，［FeO3OAT］。对乙酸的丙酮化反应活性［Fe3OAT］明显低于［Fe3OAH］［OAH＝（μ3-O）（μ-O2CCH3）6（H2O）3］。对乙酸的甲烷化反应活性［Cr3OAT］也明显低于［CrOAH］。并对上述［Fe3OAT］，［Cr3OAT］与［Fe3OAH］，［Cr3OAH］之间差异进行了讨论     

利用原位红外光谱研究若干过渡金属氧化物-丙酸体系，Fe2Cr（μ3-O）（μ-O2CC2H5）6（H2O）3Cl*xH2O及Cr3（μ3-O）（μ-O2CC2H5）6（H2O）3NO3*xH2O的反应行为

利用原位红外光谱法研究标题化合作在N2 中的反应行为。发现它们在不同温度下能使丙酸分别转化为乙醛和戊酮。金属氧化物对丙酸的戊酮化反应活性顺序是 :Fe3O4 >MnO2 >Cr2 O3>Co2 O3>Ni2 O3,这顺序与下列簇合物对该反应的活性顺序类似 :[Fe2 MnOPH]>[Fe3OPH]>[Fe2 CrOPH]>[Fe2 CoOPH]>[Fe2 NiOPH]>[Cr3OPH][OPH =(μ3 O) (μ O2 CC2 H5) 6(H2 O) 3]。对于戊酮化反应 ,过渡金属氧化物的反应温度明显高于相应的 [Fe2 MOPH]的反应温度 ,这旁证了 [Fe2 MOPH]的活性组分不是其金属氧化物。还讨论了Fe3O4 ,Fe2 O3 对丙酸分别转化为乙醛和戊酮反应活性的明显差异。     

Stereodynamics of the O（^3p） with H： （D2） （v = O,j =O） reaction

Quasi-classical trajectory theory is used to study the reaction of O（3p） with H2 （D2） based on the ground 3A″ potential energy surface （PES）. The reaction cross section of the reaction O＋H2→＋OH＋H is in excellent agreement with the previous result. Vector correlations, product rotational alignment parameters （P2（j′. k）） and several polarizeddependent differential cross sections are further calculated for the reaction. The product polarization distribution exhibits different characteristics that can be ascribed to different motion paths on the PES, arising from various collision energies or mass factors.     

Dn[M（dmit）2]（D=（Bu4N）^＋,（CoCp2）^＋;n=2,1,0;M=Ni,Pd）的振动光谱

根据简正坐标分析的部分结果对标题配合物的实测红外和拉曼光谱进行了标识，计论了Ｃ＝Ｃ，Ｎ－Ｓ伸缩振动频率随配合物氧化态变化而红移或兰移的规律及意义。     

光谱法测试瓜环与2-氨基苯丙噻唑的主客体作用

利用1H NMR技术,紫外吸收光谱法和荧光光谱法考察了七、八元瓜环(cucurbit[n]urilsn=7,8)与2-氨基苯并噻唑(g)的相互作用。实验结果表明:在2pH9范围内,利用不同的光谱方法均能观察到瓜环与客体的相互作用;Q[7]与客体作用形成物质的量比为1∶1的包结配合物,Q[8]与客体形成物质的量比为1∶2的包结配合物,并计算出包结常数,同时测试了超分子体系的热力学稳定性及熵变,焓变。     

Search for the flavor-changing neutral current decay B0s--> mu(+) mu(-) in pp Collisions at sqrt[s] = 1.96 TeV with the D0 detector

We present the results of a search for the flavor-changing neutral current decay B(0)(s)--> mu(+) mu(-) using a data set with integrated luminosity of 240 pb(-1) of pp collisions at sqrt[s] = 1.96 TeV collected with the D0 detector in run II of the Fermilab Tevatron collider. We find the upper limit on the branching fraction to be B(B(0)(s)--> mu(+) mu(-)) < or= 5.0 x 10(-7) at the 95% C.L. assuming no contributions from the decay B(0)(d)--> mu(+) mu(-) in the signal region. This limit is the most stringent upper bound on the branching fraction B(0)(s)--> mu(+) mu(-) to date.     

Photo-induced reactions of hemin (DMSO) n clusters (n = 0-3) produced with electrospray ionization

Photo-induced reaction of [Fe(III)-protoporphyrin]⁺ (hemin⁺) ions solvated with dimethylsulfoxide (DMSO) is investigated by using a tandem mass spectrometer with electrospray ionization. We measure the photodissociation yields of mass-selected hemin⁺(DMSO)_n clusters for n = 0-3 in the energy region of 15 800-28 200 cm^-1. The mass spectra of the fragment ions show the β-cleavage of carboxymethyl groups in addition to the evaporation of solvent molecules. Yield of the β-cleavage reaction is found to depend strongly on the excitation energy and the number of solvent molecules. We also examine the metastable decomposition of the clusters following primary mass selection and determine the incremental solvent binding energies and internal energies for the clusters using evaporative ensemble model. From these results, we investigate the reaction mechanism of β-cleavage of hemin⁺ ion.     

含O3MoS3单元的配合物[Mox（CO）y（O,S—C6H4—1,2）3FezLm[^n—（x=1,2或3,y=0,3

用红外光谱研究标题配合物的结构,得到了很有意义的结果。     

Mn_2[V_(12)B_(16)O_(52)(OH)_6](en)_2(H_3O)_6(H_2O)_5(en=ethylenediamine)的结构及谱学研究

采用水热合成法合成了一种结构新颖的多硼钒氧簇化合物Mn2[V12B16O52(OH)6](en)2(H3O)6(H2O)5(en=ethylenediamine)1,通过单晶X射线衍射确定该化合物的结构。化合物1中,在ab平面上,簇单元之间通过[Mn(H2O)2]2+连接成二维层状结构,另外,层与层之间在c方向上通过氢键连接成三维空间结构。此外,对化合物1的谱学性质进行了红外光谱、磁和热微扰下的二维红外相关光谱、紫外-可见固体漫反射光谱分析,探讨了其结构与谱学性质的关系。磁微扰的二维红外相关光谱表明B—O,V—O—V和Mn—O—B的伸缩振动对于磁场的变化比较敏感,热微扰的二维红外相关光谱表明B—OH,B—O,V—O—V和Mn—O—B的伸缩振动对热微扰比较敏感。     

81Br NQR Study of [NH3(CH2) n NH3]CdBr4 (n = 4 and 5) and [NH3(CH2) n NH3]ZnBr4 (n = 5 and 6)

⁸¹Br NQR frequencies and differential scanning calorimetry (DSC) were measured as a function of temperature. [NH₃(CH₂)₄ NH₃]CdBr₄ (1) and [NH₃(CH₂)₅NH₃]CdBr₄ (2) showed a doublet and quartet ⁸¹Br NQR spectrum, respectively. [NH₃(CH₂)₅NH₃]ZnBr₄ (3) and [NH₃(CH₂)₆NH₃]ZnBr₄ (4) exhibited a four-line ⁸¹Br NQR spectrum. From the NQR results, it is inferred that (1) and (2) consist of infinite two-dimensional sheets of corner-sharing CdBr₆ octahedra, whereas (3) and (4) have isolated [ZnBr₄]²⁻ tetrahedra. All of the crystals except (1) showed at least one structural phase transition above 380 K.     

Search for doubly charged higgs boson pair production in the decay to mu(+)mu(+)mu(-)mu(-) in pp collisions at sqrt[s]=1.96 TeV

A search for pair production of doubly charged Higgs bosons in the process pp -->H(++)H(--) -->mu(+)mu(+)mu(-)mu(-) is performed with the D0 run II detector at the Fermilab Tevatron. The analysis is based on a sample of inclusive dimuon data collected at an energy of sqrt[s]=1.96 TeV, corresponding to an integrated luminosity of 113 pb(-1). In the absence of a signal, 95% confidence level mass limits of M(H(+/-+/-)(L))>118.4 GeV/c(2) and M(H(+/-+/-)(R))>98.2 GeV/c(2) are set for left-handed and right-handed doubly charged Higgs bosons, respectively, assuming 100% branching into muon pairs.     

荧光光谱法考察七、八元瓜环与甲基吲哚的相互作用

利用荧光光谱法考察了七、八元瓜环(Cucurbit[n=7,8]urils,Q[7],Q[8])与客体2-甲基吲哚(2-methylindol,Me)和3-甲基吲哚(3-methylindol,Sk)的相互作用;同时研究了体系pH以及温度对Q[7]和Q[8]与客体相互作用的影响;并计算了相应的稳定常数及热力学参数等.实验结果表明:除Q[8]与Sk作用比为1∶2外,其余主客体的作用比均为1∶1;在pH值为1～11,温度为298～313 K的范围内上述体系的作用比不变;在pH 1和室温条件下,作用体系的稳定常数较大;通过热力学参数的测定可知上述主客体的相互作用均是自发进行.