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排序方式: 共有499条查询结果,搜索用时 12 毫秒
91.
92.
Nathan A. Lacher Qian Wang Rachel K. Roberts Heidi J. Holovics Serdar Aykent Michael R. Schlittler Melissa R. Thompson Charles W. Demarest 《Electrophoresis》2010,31(3):448-458
A CGE method for monitoring the disulfide isomer distribution characteristic of IgG2 MAbs is presented. Disulfide heterogeneity of MAbs has been studied using various chromatographic and electrophoretic methods. Although CGE operates using a different selectivity mechanism from that of sorption chromatographic techniques, similar trends are present in the data, which allow the CGE method to be used as a complementary method for studying disulfide isomer distribution. This article focuses on the optimization of a capillary‐based gel electrophoresis method that can be used to support antibody development including bioprocess optimization, antibody characterization, release, and formulation stability assessment. 相似文献
93.
Abstract A pair of CuII coordination isomers [Cu(pmt)2] · 4H2O (1) and {[Cu(pmt)2] · 2H2O}
n
(2) [Hpmt = 2-(2-pyridylmethylamino) ethanesulfonic acid] have been prepared by reaction of the same proportion CuCl2 · 2H2O and Hpmt but with different experimental methods in water–methanol mixed solution, and were characterized by X-ray diffraction,
elemental analysis, IR spectrum. X-ray analysis indicates that complex (1) is a mononuclear complex in which two deprotonated pmt ligands coordinate in a facial tridentate arrangement about the CuII atom. While complex (2) is a coordination polymer, in which four N atoms of pmt ligands coordinate to one CuII atom but its sulfonate O atoms bond to adjacent CuII atom. Thus 12-membered rings (–Cu–N–C–C–S–O–)2 are obtained between two neighbouring CuII atoms and they connect one another to form this new polymer. Crystal data: [Cu(pmt)2] · 4H2O (1), Mr = 566.10, monoclinic, P2
1/c, a = 9.1950(8) ?, b = 11.5093(10) ?, c = 11.2304(10) ?, β = 105.5550(10)°, Z = 2, V = 1144.96(17) ?3, R
1
= 0.0407, wR
2
= 0.1242 [I > 2σ (I)]; {[Cu(pmt)2] · 2H2O}
n
(2), Mr = 530.07, triclinic, P-1, a = 7.6165(19) ?, b = 8.806(2) ?, c = 9.592(4) ?, α = 104.933(4)°, β = 106.732(4)°, γ = 109.503(3)°, Z = 1, V = 534.2(3) ?3, R
1 = 0.0470, wR
2 = 0.1082 [I > 2σ(I)].
Index Abstract A pair of CuII coordination isomers [Cu(pmt)2] · 4H2O (1) and {[Cu(pmt)2] · 2H2O}
n
(2) [Hpmt = 2-(2-pyridylmethylamino) ethanesulfonic acid] have been prepared by reaction of the same proportion CuCl2 · 2H2O and Hpmt but with different experimental methods in water–methanol mixed solution.
相似文献
94.
Jan C. A. Boeyens Leanne M. Cook Tak-ho Ngoi David H. Reid 《Journal of chemical crystallography》1996,26(3):215-218
The crystal structure of two isomeric oximes, C11N10N2OS have been studied by X-ray diffraction. The open-chain thiocyanato derivative is somewhat'less dense and crystallizes with the orthorhombic space group Pbcn;a,b,c=18.718(1), 10.601(3), 11.528(1) Å,Z=8. The heterocyclic isomer occurs as pseudo-orthorhombic (Cmma)twinned crystals of space group P21/n, a, b, c, =12.11(1), 7.46(1), 12.12(1) Å, 100.09(1)o,Z=4. Twinning occurs as a result of the near-equality of the monoclinica andc cell constants. 相似文献
95.
MB2镁等四种金属材料的本构关系和动态断裂研究 总被引:6,自引:1,他引:6
采用炸药爆轰-分离飞片加载装置与电容传感技术相结合,由高速示波器连续记录靶板自由面速度剖面,通过波剖面的时间分辨测量,研究了MB_2镁、LY-12铝、钨合金、2169钢四种金属材料的动力学响应特性,给出了这几种材料在弹性-理想塑性模型假设下的本构关系,还给出了它们的动态断裂强度,并对标准化层裂强度与破坏比功、屈服强度之间的相关性进行了分析和讨论。 相似文献
96.
We demonstrate the ability of all-trans DPEN as a suitable ligand for transition metals by DFT computation [B3LYP/6-311+G(2d,p) and BP86 level]. The iron complex Fe(DPEN) is a unique topological isomer of ferrocene. 相似文献
97.
近年来,中国土地制度引发诸多争论,集中体现为对宪法第十条的不同解释。许多学者试图“回到宪法”,通过对土地条款的规范宪法学解释来弥合分歧。然而,从基本权利理论出发的规范宪法学解释方案并未能消弭分歧。这一争论的实质是土地增值收益分配,不同学者在此问题上持有不同的利益关怀。土地增值收益分配与中国宪制紧密相联,现有土地制度对于处理国家与民众关系、不同利益群体之间关系、中央与地方关系具有重要意义。因此,要以慎言违宪的态度对待宪法确立的土地制度基本架构。对于决策层而言,需要注意土地制度的变动,特别是土地增值收益分配机制的调整与中国城市化所处阶段相匹适,审慎权衡此种变动所带来的一系列影响。 相似文献
98.
Shenzhen Cong Yunqi Zhou Chenglian Luo Caixia Wang Prof. Jixiao Wang Prof. Zhi Wang Prof. Xinlei Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(15):e202319894
Membrane-based separation has the merit of low carbon footprint. In this study, the pore size of metal–organic framework (MOF) membranes is rationally designed for discriminating various pairs of hydrocarbon isomers. Specifically, Zr-MOF UiO-66 (UiO stands for University of Oslo) membranes are developed for separating p/o-xylene due to their proper pore size. For n-hexane/2-methylpentane separation, the functional groups and proportion of the ligands in UiO-66 are gradually adjusted to effectively regulate the pore size, and UiO-66-33Br membranes are constructed. In addition, relying on the utilization of ligands with shorter length, MOF-801 membranes with smaller pore size are fabricated for n/i-butane separation. 相似文献
99.
使用密度泛函方法(B3LYP)和6-311 G(3df,3pd)基组计算得到了HPO3体系的9个异构体与11个过渡态,并用内禀反应坐标理论验证了异构体的异构化过程.结果表明,在HPO3体系中,只有热力学最稳定的平面型异构体HOFO2(E1),(cis,cis)构象的HOOPO(E3)和立体的具有Cs对称性的异构体HP(O)O2(E7)具有较高的动力学稳定性,理论预测结果与实验一致.另外2个立体的HOFO2连接方式的异构体(E2和E4)由于解离为HO(Ⅱ) OPO(^2A1)的解离能较低,因此不能稳定存在。 相似文献
100.
合成了6种钨硅杂多配合物异构体α、βi-M3H2[SiW11(NbO2)O39]·H2O(M=Me4N+(TMA),Bu4N+(TBA),Et4N+(TEA);βi=β1,β2,β3)。IR光谱、UV光谱、极谱、I--S2O32-滴定证明合成的杂多配合物中有NbO2基存在, 183W NMR光谱证明其阴离子具有Keggin结构,催化实验结果表明,合成的化合物对烯烃环氧化反应具有催化活性,且过氧杂多配合物的催化活性高于非过氧杂多配合物,β异构体的催化活性高于α。 相似文献