火炸药中的几个化学概念

本文针对火炸药组份的分子结构特点,燃烧、爆炸过程中元素氧化态的变化情况,提出了氧化态变化数、绝对氧化态变化数、实际绝对氧化态变化数等新的化学概念。用这些化学概念不仅可以说明火炸药的氧化性和可燃性,而且能表征其潜在的和实际的反应特征。这对火炸药分子特性的了解有重要的指导性的意义。     

应用传输线网模拟技术对非线性电路故障诊断的研究

本文利用传输线网模拟技术(T.L.M.)将电路的线性和非线性部分有效地分隔开,从而使非线性电路的故障诊断简化为线性电路的拟故障集定位,然后经过简单的测后计算即可确定真正的非线性故障元件。     

电厂筛碎贮仓楼振动与抗震性能的研究规划——电厂筛碎贮仓楼振动与抗震性能研究之一

本文概括地介绍东北电力设计院与哈尔滨建筑工程学院钢筋混凝土结构研究室的科研合作项目“电厂筛碎贮仓楼振动与抗震性能”的研究规划,包括课题的工程背景及意义、研究内容与方法等。     

三维机织间隔复合材料结构对其力学性能的影响

以玻璃纤维为原料,设计3种不同结构的三维机织间隔织物,采用手糊成型工艺制备三维机织间隔复合材料,研究了其在压缩、剪切、弯曲等载荷作用下的力学特性,并分析了材料结构对其力学性能的影响。结果表明,相同高度(20 mm)、相同间隔(30 mm)的3种三维机织间隔复合材料的压缩强度和剪切强度均表现为:三维纤维间隔复合材料<"X"型间隔复合材料<三维织物间隔复合材料,其压缩强度分别为0.52,0.72,1.66 MPa,剪切强度分别为0.22,0.28,0.36 MPa;3种三维机织间隔复合材料的弯曲强度基本相同,均为4.30 MPa左右。     

Genome-Wide Identification and Characterization of Soybean GmLOR Gene Family and Expression Analysis in Response to Abiotic Stresses

The LOR (LURP-one related) family genes encode proteins containing a conserved LOR domain. Several members of the LOR family genes are required for defense against Hyaloperonospora parasitica (Hpa) in Arabidopsis. However, there are few reports of LOR genes in response to abiotic stresses in plants. In this study, a genome-wide survey and expression levels in response to abiotic stresses of 36 LOR genes from Glycine max were conducted. The results indicated that the GmLOR gene family was divided into eight subgroups, distributed on 14 chromosomes. A majority of members contained three extremely conservative motifs. There were four pairs of tandem duplicated GmLORs and nineteen pairs of segmental duplicated genes identified, which led to the expansion of the number of GmLOR genes. The expansion patterns of the GmLOR family were mainly segmental duplication. A heatmap of soybean LOR family genes showed that 36 GmLOR genes exhibited various expression patterns in different tissues. The cis-acting elements in promoter regions of GmLORs include abiotic stress-responsive elements, such as dehydration-responsive elements and drought-inducible elements. Real-time quantitative PCR was used to detect the expression level of GmLOR genes, and most of them were expressed in the leaf or root except that GmLOR6 was induced by osmotic and salt stresses. Moreover, GmLOR4/10/14/19 were significantly upregulated after PEG and salt treatments, indicating important roles in the improvement of plant tolerance to abiotic stress. Overall, our study provides a foundation for future investigations of GmLOR gene functions in soybean.     

Fluidity improvement of semiaromatic polyamides: Modification with oligomers

Poly(decamethylene terephthalamide) PA10T with different relative viscosities (RV) were successfully produced by the reaction of 1,10‐decanediamine and terephthalic acid through molecular weight regulator benzoic acid (BA). RV was shown to be decreased linearly with increasing BA concentrations and detailed structures of PA10Ts were characterized by ¹³C‐NMR. Fluidity of PA10T with varying molecular weight was tested and low RV PA10Ts were used as modifiers to improve fluidity behaviors of high RV PA10Ts, meanwhile mechanical properties were maintained. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40058.     

Enhancing the Nucleolytic Resistance and Bioactivity of Functional Nucleic Acids by Diverse Nanostructures through in Situ Polymerization-Induced Self-assembly

Functional nucleic acids (FNAs) are garnering tremendous interest owing to their high modularity and unique bioactivity. Three-dimensional FNAs have been developed to overcome the issues of nuclease degradation and limited cell uptake. We have developed a new facile approach to the synthesis of multiple three-dimensional FNA nanostructures by harnessing photo-polymerization-induced self-assembly. Sgc8 aptamer and CpG oligonucleotide were modified as macro chain-transfer reagents to mediate in situ polymerization and self-assembly. Diverse structures, including micelles, rods, and short worms, afford these two FNAs afford these two FNAs with higher nuclease resistance in serum serum, greater cellular uptake efficiency, and increased bioactivity.     

Competitive Cr3+ occupation in persistent phosphors toward tunable traps distribution for dynamic anti-counterfeiting

Red/near infrared (NIR) long persistent phosphors have received extensive attentions in biomedical, food inspection, iris recognition, biological imaging, etc. Herein, a new phosphor, Li₂ZnGe₃O₈:Cr³⁺, is reported with deep red persistent luminescence peaking at 708 nm. By adjusting the Cr³⁺ doping concentration, the competitive site occupation at [ZnO6] and [GeO6] polyhedral enables different traps behaviors including trap types, trap concentration and trap depth, which in turn leads to different afterglow duration time from 2 to 20 h. The persistent luminescence mechanisms originated from different trap models have been discussed, and it is found that they can cooperate or inhibit each other, enabling different luminescence depending on time. The dynamic anti-counterfeiting applications have been demonstrated, which provides a new way to rationally designing for multi-functional luminescent materials.     

Structure and Dielectric Properties of BaTiO3–BiYO3 Perovskite Solid Solutions

(1?x)BaTiO₃–xBiYO₃ [(1?x)BT–xBY] polycrystalline ceramics were prepared by solid‐state reaction method. The ceramics are in tetragonal phase when x ≤ 0.04, transform to pseudocubic at x ≥ 0.06, showing a classic ferroelectric to relaxor transition at x = 0.06, where the phase transition temperature was found to shift to higher temperature with increasing frequency. The dielectric permittivity peaks were analyzed by the modified Curie–Weiss law. Both parameters ΔT_diffuse and ΔT_relaxor were found to increase with increasing BY content, demonstrating a stronger relaxor characteristic.