未来电子战中通信抗干扰技术的探讨

当今经济发展的新时代,信息技术不断发展,通信技术飞速进步,战争的信息化程度不断增强,由此可见,电子与信息技术将在今后的战争中具备举足轻重的地位,呈现出日益兴盛的发展趋势。未来的战争形态必将是信息化战争,电子技术的较量将影响战争的发展趋势,电子信息也必将贯穿战争的整个过程。信息随着时代发展已经成为一种无形但却无比现实同时又具备强大力量的新型战斗方式。文章对未来电子战中通信抗干扰技术进行了研究与探讨。     

NMR studies of Na2O---B2O3---SiO2 glasses of mid-alkali content

¹¹B Fourier transform spectra have been used to study the structure of Na₂O---B₂O₃---SiO₂ glasses of mid-alkali content. Based on the measurements of the fraction N₄ of four-coordinated borons, it has been found that for K = mol.% SiO₂/mol.% B₂O₃ 8 and R = mol.% Na₂O/mol.% B₂O₃ = 1, N₄ is obviously smaller than 1 rather than equal to 1 as assumed in the relevant literature. Only when R reaches a value appropriately greater than 1, can the case where N₄ = 1 occur. A structural model suggested in this paper can satisfactorily explain the fact.     

Solution‐Processed Nanoporous Organic Semiconductor Thin Films: Toward Health and Environmental Monitoring of Volatile Markers

Porous materials are ubiquitous in nature and have found a wide range of applications because of their unique absorption, optical, mechanical, and catalytic properties. Large surface‐area‐to‐volume ratio is deemed a key factor contributing to their catalytic properties. Here, it is shown that introducing tunable nanopores (50–700 nm) to organic semiconductor thin films enhances their reactivity with volatile organic compounds by up to an order of magnitude, while the surface‐area‐to‐volume ratio is almost unchanged. Mechanistic investigations show that nanopores grant direct access to the highly reactive sites otherwise buried in the conductive channel of the transistor. The high reactivity of nanoporous organic field‐effect transistors leads to unprecedented ultrasensitive, ultrafast, selective chemical sensing below the 1 ppb level on a hundred millisecond time scale, enabling a wide range of health and environmental applications. Flexible sensor chip for monitoring breath ammonia is further demonstrated; this is a potential biomarker for chronic kidney disease.     

Isolation, structure determination, and synthesis of galaxamide, a rare cytotoxic cyclic pentapeptide from a marine algae Galaxaura filamentosa

Galaxamide (1), a rare cyclic pentapeptide, was isolated from the marine algae Galaxaura filamentosa. A preliminary bioassay of Galaxamide showed remarkable in vitro antiproliferative activities against GRC-1 and HepG2 cell lines. The first total synthesis of the cyclic peptide was achieved for further biological evaluation.     

Simple method for synthesizing few-layer graphene as cathodes in surface-enabled lithium ion-exchanging cells

In order to realize a wider application for graphene materials specifically in the field of energy storage, a simple and mass-scalable method described as “the atmospheric, low-temperature, shock-heating process” is proposed in this work. During this low-temperature process, the graphite oxide without pre-treatment is completely exfoliated to form the few-layer graphene materials at atmospheric conditions. The Brunauer-Emmett-Teller (BET)-specific surface area of acquired material at 350 °C can reach 487 m² g^?1. The acquired few-layer graphene materials are also confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HRTEM). The results demonstrate that this simple method is feasible for synthesizing the few-layer graphene materials. Besides that, the acquired graphene is also used as the cathode material in the surface-enabled lithium ion-exchanging cell. The galvanostatic charge/discharge tests show that the graphene prepared from this method is suitable for this system and displays a satisfactory electrochemical performance. The acquired graphene sample exhibits the reversible capacities of around 187, 107, 84, 58, and 45 mAh g^?1 at 0.1, 2, 5, 10, and 15 A g^?1, respectively. At the current density of 0.5 A g^?1, the capacity retention can reach 75 % after 2000 cycles.     

Electrochemical strategy for ultrasensitive detection of microRNA based on MNAzyme-mediated rolling circle amplification on a gold electrode

Microchimica Acta - The authors describe an electrochemical strategy for ultrasensitive and specific detection of microRNA (miRNA). It is based on both multicomponent nucleic acid enzyme (MNAzyme)...     

Fluorescence-detecting cationic surfactants using luminescent CdTe quantum dots as probes

A novel fluorescence quenching method for the determination of cationic surfactants (CS), specifically cetyltrimethylammonium bromide (CTAB), dodecyltrimethylammonium bromide (DTAB), and cetylpyridinium chloride (CPC), has been developed using water-soluble luminescent CdTe quantum dots (QDs) modified with thioglycolic acid (TGA). The possible interference from heavy and transition metals (HTM) has been efficiently eliminated through simple sample treatment with mercapto cotton made in-house. Under optimum conditions, the extent of fluorescence quenching of CdTe QDs is linearly proportional to the concentration of CS from 2.0 × 10⁻⁷ to 7.0 × 10⁻⁶ mol L⁻¹ with a detection limit of 5.0 × 10⁻⁸ mol L⁻¹. The relative standard deviation for 1.0 × 10⁻⁶ mol L⁻¹ CTAB is 2.5% (n = 6). The proposed method exhibits high sensitivity and selectivity and furthermore avoided the use of toxic organic solvents and tedious solvent extraction procedures. It has been applied to the determination of trace CS in natural river water and commodity samples with satisfactory results. Potential interference from heavy and transition metals is eliminated during photoluminescence detection of CS through simple sample pre-treatment with mercapto cotton     

场发射锥尖的制备及特性研究

研究了倒金字塔填充型锥尖及正向刻蚀硅尖的制备工艺,采用了两种封装结构测试了场发射硅尖阵列的发射特性,并分析比较了这两种结构的特点及用于制备高频微波器件的可能性。     

展望21世纪的环境电磁学及电磁兼容技术（下）

简要介绍当前环境电磁学及电磁兼容技术发展中的几个突出问题,着重介绍空间飞行器、无线通信系统和计算机的电磁兼容问题以及电磁场的生态效应。