水溶性光敏引发剂2-羟基-1-[4-(2-羟乙氧基)苯基]-2-甲基-1-丙酮

介绍了一种水溶性光敏引发剂２－羟基－１－［４－（２－羟乙氧基）苯基］－２－甲基－１－丙酮的新的合成方法,作了光谱、波谱分析,该引发剂特别适用于乳液型或胶乳型水溶性体系中的不饱和化合物的光聚合反应。新合成方法是将中间产物在四氯化碳介质中溴化,然后进行甲醇钠催化水解     

Dynamics study on the anti-human immunodeficiency virus chemokine viral macrophage-inflammatory protein-II (VMIP-II) reveals a fully monomeric protein

Encoded by Kaposi's sarcoma-associated herpesvirus, viral macrophage-inflammatory protein-II (VMIP-II) is unique among CC chemokines in that it has been shown to bind to the CXC chemokine receptor CXCR4 as well as to a variety of CC chemokine receptors. This unique binding ability allows vMIP-II to block infection by a wide range of human immunodeficiency virus type I (HIV-1) strains, but the structural and dynamic basis for this broad range of binding is not known. 15N T1, T2 and 15N[-HN] nuclear Overhauser effect (NOE) values of vMIP-II, determined through a series of heteronuclear multidimensional nuclear magnetic resonance (NMR) experiments, were used to obtain information about the backbone dynamics of the protein. Whereas almost all chemokine structures reveal a dimer or multimer, vMIP-II has a rotational correlation time (tauc) of 4.7 +/- 0.3 ns, which is consistent with a monomeric chemokine. The rotational diffusion anisotropy, D parallel/D perpendicular, is approximately 1.5 +/- 0.1. The conformation of vMIP-II is quite similar to other known chemokines, containing an unstructured N-terminus followed by an ordered turn, three beta-strands arranged in an antiparallel fashion, and one C-terminal alpha-helix that lies across the beta-strands. Most of the protein is well-ordered on a picosecond time scale, with an average order parameter S2 (excluding the N-terminal 13 amino acids) of 0.83 +/- 0. 09, and with even greater order in regions of secondary structure. The NMR data reveal that the N-terminus, which in other chemokines has been implicated in receptor binding, extends like a flexible tail in solution and possesses no secondary structure. The region of the ordered turn, including residues 25-28, experiences conformational exchange dynamics. The implications of these NMR data to the broad receptor binding capability of vMIP-II are discussed.     

渣油悬浮床加氢裂化水溶性催化剂的研究

采用悬浮床加氢技术和水溶性分散催化剂对辽河坨子里稠油的常压渣油进行了轻质化和改质研究。对催化剂金属组成、催化剂应用条件和过程生焦及转化率的关系进行了系统考察,试验结果经数学处理后得到各关系曲线。研究结果表明,在催化剂加入量２５０μｇ／ｇ、反应温度４３５℃、反应空速１．０ｈ－１和１０ＭＰａ条件下单程通过反应处理坨子里常压渣油得到轻柴油和减压馏分油的质量收率分别为３１．２％及４０．７％。     

Hydrogen generation by glow discharge plasma electrolysis of methanol solutions

This paper investigated the glow discharge plasma electrolysis (GDPE) of methanol solutions for hydrogen generation. It is known that H₂ and HCHO are the dominant products of methanol decomposition during GDPE. The experimental results indicate that high-energy electrons are the most important species to initiate methanol decomposition. Likewise, it was shown that discharged polarity, discharged voltage, and methanol concentration have important influences on hydrogen yield, energy consumption, hydrogen concentration, and hydrogen and formaldehyde output. The hydrogen yield (G(H₂)) of cathodic GDPE (CGDPE) was found to be higher than that of anodic GDPE (AGDPE). In addition, the hydrogen concentration in liberated gas from CGDPE remains above 88% after the separation of HCHO when the applied voltage is higher than 750 V. The energy consumption (W_r) of CGDPE is significantly less than AGDPE. Furthermore, W_r decreased with the increase in discharged voltage, while G(H₂) increased with methanol concentration. The experimental results show that the GDPE of methanol solutions is a promising technique for the simultaneous production of hydrogen and formaldehyde.     

节理岩巷应力分布规律与失稳机制研究

为研究具有层状特征的节理岩巷应力分布规律与变形机制及控制对策,通过将巷道直墙拱形断面等效为圆形断面,分析层状节理岩巷应力分布和应力集中影响,并以云南某矿埋深为750 m的阶段运输巷道为研究对象,通过现场调查和Phase 2数值模拟等方法,分析了巷道变形机制并给出了相应的支护对策.结果表明:通过粒子群算法得出的巷道应力集...     

武钢实施“工作质量”控制的实践及研究

工作质量控制被认为是很有用的一种质量方法,是保证符合质量要求的一种有价值的途径。它是一种有计划的工作过程检查以及对产品或服务缺陷的投诉,以确定是否符合工作过程的某些程序。本文描述了如何建立一个积极的改进的工作质量控制体系,以确保质量体系持续的适应性和有效性。     

Effect of N-terminal truncation and solution conditions on chemokine dimer stability: nuclear magnetic resonance structural analysis of macrophage inflammatory protein 1 beta mutants

Chemokines (chemotactic cytokines) are a family of immune system proteins, several of which have been shown to block human immunodeficiency virus (HIV) infection in various cell types. While the solved structures of most chemokines reveal protein dimers, evidence has accumulated for the biological activity of individual chemokine monomers, and a debate has arisen regarding the biological role of the chemokine dimer. Concurrent with this debate, several N-terminal truncations and modifications in the CC subfamily of chemokines have been shown to have functional significance, in many cases antagonizing their respective receptors and in some cases retaining the ability to block HIV entry to the cell. As the dimer interface of CC chemokines is located at their N-terminus, a structural study of N-terminally truncated chemokines will address the effect that this type of mutation has on the dimer-monomer equilibrium. We have studied the structural consequences of N-terminal truncation in macrophage inflammatory protein 1 beta (MIP-1 beta), a CC chemokine that has been shown to block HIV infection. Examination of nuclear magnetic resonance (NMR) spectra of a series of N-terminally truncated MIP-1 beta variants reveals that these proteins possess a range of ability to dimerize. A mutant beginning at amino acid Asp6 [termed MIP(6)] has near wild-type dimer properties, while further truncation results in weakened dimer affinity. The mutant MIP(9) (beginning with amino acid Thr9) has been found to exist solely as a folded monomer. Relaxation measurements yield a rotational correlation time of 8.6 +/- 0.1 ns for wild-type MIP-1 beta and 4.5 +/- 0.1 ns for the MIP(9) mutant, consistent with a wild-type dimer and a fully monomeric MIP(9) variant. The presence of physiological salt concentration drastically changes the monomer-dimer equilibrium for both wild-type and most mutant proteins, heavily favoring the dimeric form of the protein. These results have implications for structure-function analysis of existing chemokine mutants as well as for the larger debate regarding the biological existence and activity of the chemokine dimer.     

新型喷雾干燥塔出粉装置—双刮板工闭风卸料器

分析了转鼓式闭风卸料器失败的原因,设计了一种喷雾干燥塔使用的新型双刮板式闭风卸料器,以解决转鼓式闭风卸料器的失效问题。