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1.
以二甘醇和邻苯二酚为原料制得二苯并-18-冠-6;以多聚磷酸为催化剂和溶剂,将二苯并-18-冠-6与叔丁醇反应实现叔丁基化;利用正庚烷重结晶对叔丁基化反应产物进行纯化,得到4,4′-二叔丁基二苯并-18-冠-6和4,5′-二叔丁基二苯并-18-冠-6两种对称的二叔丁基二取代苯并冠醚产品.利用红外光谱和核磁共振谱表征了二叔丁基二取代苯并冠醚产物的结构。  相似文献   
2.
利用反应显微谱仪对70keV He2+-He转移电离过程中的出射电子进行了成像,研究了出射电子的空间速度分布特征.结果表明:电子主要集中在散射平面内;在散射平面内,电子速度分布介于零与入射离子速度Vp之间(即前向出射)且在散射离子和靶核核间轴处有一极小值,呈现出典型的双峰结构.出射电子的上述分布特征可由出射电子波函数σ振幅和π振幅的干涉进行定性解释,σ振幅和π振幅对出射电子波函数的贡献与碰撞参数相关.在小碰撞参数下,π振幅的贡献更加明显;而在大碰撞参数下,σ振幅的贡献更加显著.  相似文献   
3.
在中温水热反应条件下,以CoCl2·6H2O、2,6-萘二羧酸(2,6-pda)和4,4'-bpy为原料,合成了一种二维互穿配位聚合物[Co3(2,6-nda)3(4,4'-bpy)1.5]n晶体,对其进行了元素分析、红外光谱表征、TGA-GTA分析和X射线单晶衍射测定.该配位聚合物属单斜晶系,C2/m空间群,晶胞参数为a=1.7285(11)nm,b=1.9965(13)nm,c=1.3994(9)nm,α=90°,β=95.822(11)°,γ=90°,V=4.804(5)nmm3,Z=4,dc=1.457g/cm3,μ=1.089mm-1,F(000)=2136,R1=0.0594,wR2=0.1605.结果显示形成一个二维互穿的网络结构.  相似文献   
4.
The treatment of pyrrolidine(C_4H_8NH) with sequentially trimethylaluminum and carbodiimide Cy N=C=NCy in a molar ratio of 1:1:1 in the presence of O_2 afforded a new guanidinatoaluminum complex, [{(C_4H_8N)C(NCy)_2}Al Me(μ-OMe)]2(1), which was characterized by elemental analyses, ~1H, ~(13)C NMR spectra and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in monoclinic, space group P21/c with a = 9.8330(9), b = 8.5786(8), c = 24.159(2) ?, β = 92.927(2)°, V = 2035.3(3) ?3, Dc = 1.141 g cm-3, F(000) = 768 and μ = 0.110 mm-1. In addition, complex 1 was used to catalyze the Meerwein-Ponndorf-Verley(MPV) reduction and 1 as a pre-catalyst at low catalyst loadings(5 mol%) exhibited good catalytic activity for the reduction of a series of aldehydes to the corresponding alcohols in good yields(conv. up to 99%).  相似文献   
5.
利用反应显微成像谱仪对70和100keV He2+与He原子碰撞转移电离(TI)过程中不同出射角度的电子能谱进行了测量,观测到出射电子能谱具有如下分布特征:出射电子速度分布介于0和入射离子速度vp之间;在不同出射角度电子能谱分布均有一极大值存在,随着出射角度的增大,能谱分布极大值逐渐减小;当电子出射角度等于45°时,多数电子集中在0eV附近。上述特征可由低能离子-原子碰撞"准分子"模型进行定性解释。在100keV He2+-He转移电离出射电子能谱中有靶电子被俘获至散射离子连续态(electron capture to continuum,简称ECC)电子的贡献,这可看做是动力学两步过程的作用。  相似文献   
6.
利用冷靶反冲离子动量谱仪,对电子轰击Ne原子的单电离反应(e,2e)进行了研究,实验测量了70—3300eV入射能量情况下,反应过程中产生的一价反冲离子的动量分布,并对反冲离子的总动量进行了还原。介绍了一个简单的碰撞机制,据此着重分析了反冲离子纵向动量和横向动量二维谱形成的原因,该碰撞机制能够较好地解释较高能量入射时的实验结果。最后根据反冲离子的动量,估算了出射电子的能量范围,为下一步进行电子、离子的符合测量奠定了基础。  相似文献   
7.
A new bismuth(III) iodide inorganic/organic hybrid containing larger heterocyclic conjugated organic ligand, [(dppz)2Bi2I6]·2DMF(1)(dppz = dipyrido[3,2-a:2',3'-c]phenazine), has been synthesized by solution process and structurally determined by X-ray diffraction method. 1 crystallizes in triclinic, space group P1 with Mr = 1844.08, a = 9.215(5), b = 11.488(6), c = 12.424(9) ?, α = 106.66(2), β = 90.84(2), γ = 92.34(2)°, V = 1258.5(13)?3, Z = 1, Dc = 2.433 g/cm3, F(000) = 830, μ(MoKα) = 10.702 mm–1, the final R = 0.0834 and wR = 0.1947 for 2749 observed reflections with I 2σ(I). 1 consists of a dimeric structure [(dppz)2Bi2I6], in which two [(dppz)BiI3] fragments are bridged by a pair of iodine atoms. Hydrogen bonds and π···π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 2.13 eV indicates its semiconductor nature. The optical absorption spectrum and electronic structure were also discussed.  相似文献   
8.
Employing the recoil ion momentum spectroscopy we investigate the collision between He^2+ and argon atoms. By measuring the recoil longitudinal momentum the energy losses of projectile are deduced for capture reaction channels. It is found that in most cases for single- and double-electron capture, the inner electron in the target atom is removed, the recoil ion is in singly or multiply excited states (hollow ion is formed), which indicates that electron correlation plays an important role in the process. The captured electrons prefer the ground states of the projectile. It is experimentally demonstrated that the average energy losses are directly related to charge transfer and electronic configuration  相似文献   
9.
测量了入射离子能量为27 keV、45 keV和66 keV时Ar3 Ar碰撞反应各子过程的分截面,通过将其归一化到Bliman,Dousson等人所测量的截面值,获得了绝对截面.结果表明,该能区电子俘获过程仍占主导地位,但转移电离过程已不能忽略.结果还表明,各子过程反应截面基本不随能量变化.与考虑自电离的MCBM(Molecular Coulombic overBarrier Model)模型比较发现,模型所给截面普遍高于实验测量值,这在一定程度上是由于归一化时带来的系统误差.在误差允许的范围内,单电子和双电子俘获截面符合的比较好,但三电子俘获截面却相差一个数量级.对于实验观测到的转移电离过程,模型却预言并没有此过程发生.  相似文献   
10.
利用反应显微成像谱仪,研究了50 keV/u Ne8+碰撞CO转移电离反应中生成的CO2+碎裂过程。通过重构分子离子爆炸碎片C+和O+的三维动量,获得了质心系中CO2+碎裂过程中释放的动能(KER)。在KER谱中发现了来自亚稳态1Σ+,1Π,3Π解离的峰、3Σ+态解离的峰和1Σ(II)+态解离的峰,同时发现了排斥态3Σ-的贡献。在3Σ-态解离的分子轴取向分布中,首次观测到CO2+解离的分子轴取向效应。The fragmentations of CO2+ are studied in transfer ionization processes of 50 keV/u Ne8+ impact on CO with reaction microscopes. The 3D momenta of C+ and O+ were measured, and the kinetic energy release (KER) of dissociative(CO2+) was obtained accordingly. The peaks resulted from the metastable states of 1Σ+, 1Π and 3Π, of 3Σ+, and of 1Σ(II)+ are identified in KER spectrum. Meanwhile, the repulsive state of 3Σ- was also observed, which forms a broad peak lying between the peaks of 3Σ+ and 1Σ(II)+. In the CO2+ dissociations from 3Σ- state, the orientation effect of CO molecular axis was observed for the first time.  相似文献   
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