Coexistence of ferromagnetism and metallic conductivity in a molecule-based layered compound

Crystal engineering--the planning and construction of crystalline supramolecular architectures from modular building blocks--permits the rational design of functional molecular materials that exhibit technologically useful behaviour such as conductivity and superconductivity, ferromagnetism and nonlinear optical properties. Because the presence of two cooperative properties in the same crystal lattice might result in new physical phenomena and novel applications, a particularly attractive goal is the design of molecular materials with two properties that are difficult or impossible to combine in a conventional inorganic solid with a continuous lattice. A promising strategy for creating this type of 'bi-functionality' targets hybrid organic/inorganic crystals comprising two functional sub-lattices exhibiting distinct properties. In this way, the organic pi-electron donor bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and its derivatives, which form the basis of most known molecular conductors and superconductors, have been combined with molecular magnetic anions, yielding predominantly materials with conventional semiconducting or conducting properties, but also systems that are both superconducting and paramagnetic. But interesting bulk magnetic properties fail to develop, owing to the discrete nature of the inorganic anions. Another strategy for achieving cooperative magnetism involves insertion of functional bulky cations into a polymeric magnetic anion, such as the bimetallic oxalato complex [MnIICrIII(C2O4)3]-, but only insoluble powders have been obtained in most cases. Here we report the synthesis of single crystals formed by infinite sheets of this magnetic coordination polymer interleaved with layers of conducting BEDT-TTF cations, and show that this molecule-based compound displays ferromagnetism and metallic conductivity.     

Molecular evolution of connective tissue growth factor in Cyprinidae (Teleostei: Cypriniformes)

Connective tissue growth factor (CTGF) plays an important role in regulation of cell growth, differentiation, apoptosis and individual development in animals. The study of sequences variation and molecular evolution of CTGF gene across various species of the cyprinid could be helpful for understanding of speciation and gene divergence in this kind of fish. In this study, 19 novel sequences of CTGF gene were obtained from the representative species of the family Cyprinidae using PCR amplification, cloning and sequencing. Phylogenetic relationships of Cyprinidae were reconstructed by neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian method. Oryzias latipes from the family Cyprinodontidae was assigned to be the outgroup taxon. Leuciscini and Barbini were clustered into the monophyletic lineages respectively with the high nodal supports. The estimation of the ratio of nonsynonymous to synonymous substitution (dN/dS) for the various branches indicated that there stood the different evolution rates between the Leuciscini and the Barbini. With the ratio of dN/dS of the Leuciscini being lower than that of the Barbini, species within the Barbini were demonstrated to be subjected to the relatively less selection pressure and under the relaxable evolution background. A 6 bp indel (insertion/deletion) was found at the 5' end of CTGF gene of Cyprinidae, and this 6 bp deletion only appeared in the Leuciscini, which is a typical characteristic of the Leuciscini and provides evidence for the monophylogeny of the Leuciscini. For the amino acid sequences of CTGF protein, the most variations and Indels were distributed in the signal region and IGFBP region of this protein, implying that these variations were correlated with the regulation of the CTGF gene expression and protein activity.     

Serial time-encoded amplified microscopy for ultrafast imaging based on multi-wavelength laser

In this paper, a serial time-encoded amplified microscopy （STEAM） by employing a multiwavelength laser as the light source is proposed and experimentally demonstrated. This system achieves ultrafast optical imaging with a tunable frame rate. The measuring range depends on the spectrum width of the multiwavelength laser. Through tuning the speed of the modulating signal, the frame rate ranges from 100 to 250 MHz. In addition, the spatial resolution can be improved by increasing the group velocity dispersion and reducing the wavelength spacing. Finally, with the development of photonic integrate circuits （PIC）, the multiwavelength laser source has the potential for integration on a photonic chip and thus the size of the proposed STEAM could be reduced in the future.     

The FN3 and BRCT motifs in the exomer component Chs5p define a conserved module that is necessary and sufficient for its function

Chs5p is a component of the exomer, a coat complex required to transport the chitin synthase Chs3p from the trans-Golgi network to the plasma membrane. The Chs5p N-terminal region exhibits fibronectin type III (FN3) and BRCT domains. FN3 domains are present in proteins that mediate adhesion processes, whereas BRCT domains are involved in DNA repair. Several fungi—including Schizosaccharomyces pombe, which has no detectable amounts of chitin—have proteins similar to Chs5p. Here we show that the FN3 and BRCT motifs in Chs5p behave as a module that is necessary and sufficient for Chs5p localization and for cargo delivery. The N-terminal regions of S. cerevisiae Chs5p and S. pombe Cfr1p are interchangeable in terms of Golgi localization, but not in terms of exomer assembly, showing that the conserved function of this module is protein retention in this organelle and that the interaction between the exomer components is organism-specific.     

含油包裹体丰度指数确定油气运聚范围及应用

GOI(含油流体包裹体丰度指标)是流体包裹体丰富程度的一种指标,其大小决定于储层或圈闭内流体的充注程度;其值及属性变化可以反映出油气的充注历史。利用这一属性,对于一个研究区而言,进行系统的GOI取样和测定,可以确定出该区的油气运聚的平面和剖面最大范围。阐述了GOI的定义、确定油气运聚范围基本原理、判别标准及操作方法,在松辽盆地滨北地区的应用结果表明,滨北地区浅部储盖组合油气运聚范围平面上主要集中在靠近滨洲铁路线20000km2的范围内,剖面上主要集中分布在1500m～2000m的深度范围内。通过油气显示方法和源控油气藏分布规律方法进行验证,证明该方法行之有效。     

屏蔽式暂堵技术在狮子沟油田的应用

针对柴达木盆地狮子沟构造地层特性及裂缝性油气藏易于受到损害的情况,结合地层水矿化度较高,易与外来流体发生物理化学反应形成沉积物,阻塞油气通道,因此采用高矿化度钻井液,最大限度地接近地层水性能,减少对油气层的污染。根据已完成的狮子沟E13油气层损害机理研究,制定了屏蔽式暂堵保护油气层技术措施,筛选了钻井液配方。经过在狮子沟油田狮25-1水平井的现场应用,表明屏蔽式暂堵技术既满足了水平井施工要求,又有较理想的保护油气层效果。     

油田产量的不均衡性分析方法研究

在油田的开发过程中,生产井数与原油产量之间,存在一定的不均衡性。借助于经济学中洛伦茨曲线和基尼系数的分析原理,在对油田产量按单井分组,对油田生产井数和原油产量计算百分比和累计百分比的基础上,通过计算基尼系数,得到油田原油产量生产的不均衡程度指标,以便在编制原油生产计划时,考虑原油生产的不均衡性,实现油田优化配产和提高油田开发效益的目的。     

疏水缔合聚合物驱油数学模型

为了研究疏水缔合聚合物驱油规律和动态,建立了疏水缔合聚合物驱油数学模型。根据室内对疏水缔合聚合物溶液结构的研究成果,采用聚合物线形体和聚合物聚集体共同描述疏水缔合聚合物溶液在多孔介质中的性质变化和渗流特性,同时考虑了疏水缔合聚合物溶液在不同孔渗条件下水相相对渗透率降低能力、不可入孔隙体积系数的变化、吸附滞留与建立流动阻力的关系等物化问题。利用模型对岩芯驱油实验结果进行了拟合,数值模拟结果与实际岩芯驱油结果基本一致。表明该模型能够有效描述疏水缔合聚合物溶液的驱油动态,为疏水缔合聚合物驱的理论研究和现场分析提供了研究方法。     

盐岩在库车拗陷中的作用

库车拗陷的勘探实践表明,盐层与油气密切相关。通过对2条地震测线的分析发现,盐层、盐上地层、盐下地层变形看似孤立,实际相互影响。盐层构造变形一般发育在古隆起上部,盐上构造变形主要发生在盐枕构造的翼部,无盐地区主要发育基底卷入式构造。膏盐层可以延缓盐下地层烃源岩的热演化程度,可以改善盐下储层的储集性能;膏盐层本身也有可能成为油气储集层;膏盐层具有形成超压封闭和物性封闭的双重封闭机制,对盐下油气藏的保存极为有利;膏盐层的塑性流动特性,使得盐下构造圈闭在强烈的构造挤压中得以保存。     

提高粉煤灰低密度水泥体系早期强度的研究

针对粉煤灰低密度混合材水泥的早强问题展开研究,用实验方法分析探讨了粉煤灰低密度混合材水泥在水化反应过程中的作用机理,开发出了一种高效的能够适用于低温低密度体系的早强剂DY,使得粉煤灰低密度水泥早期强度得到显著的提高。粉煤灰混合材低密度水泥在低温下早期强度的提高,主要通过水泥与粉煤灰之间的相互作用来实现。正反两方面的实验结果表明,水化反应使早期释放更多的Ca²⁺和OH^-,引发了粉煤灰的火山灰反应,从而促进了粉煤灰混合材水泥早期强度的发展。该产品有望在低压井、易漏井、长封固段井等复杂条件下使用。粉煤灰混合材水泥能够满足复杂井固井作业的要求,并且具有可观的经济、环保效益。