微波炉

自从微波炉进入中国市场以来，它迅速普及到千家万户，成为家庭主妇居家生活不可或缺的家电产品。微波炉在过去几年一直保持着比较高的销量，但是在进入了今年之后，微波炉市场由旺转淡，价格处在中低端的单功能和机械烧烤型微波炉．市场份额在逐步缩小，而处在中高端的电子烧烤型微波炉的市场份额却在大幅攀升。这主要是因为低端产品．特别是单功能微波炉的市场价格几乎等同于成本，根本没有再下降的空间，反观高端产品的市场价格却在持续下降，与低端产品的价差逐步缩小．加上厂家明显加大了对高端产品的促销力度．导致了主体市场向高端偏移。另外，受国内市场近年来价格战的影响，各微波炉生产厂家的盈利状况都不尽如人意，这迫使它们对自己的产品线进行了调整，低端产品的研发和投产比例大幅减少，而转向生产高附加值的高端产品。     

微波炉

随着科技的发展，微波炉也在不断的更新换代，同时随着行业竞争的加剧和市场的成熟，微波炉最终从一件奢侈品变为普通的家用电器。目前，微波炉在城市家庭的厨房已成为必备之物。从功用上来说，微波炉也确实无所不能，煎、烤、煮、炸、翻热食物，甚至做一顿可口的饭菜，都不是什么难事。但是，正是由于现在微波炉的功能花样特别多，所以很多人在选购微波炉时还是感到迷惑，到底选择什么样的微波炉呢？     

微波炉

近日,海尔微波炉获得了第三届“中国微波炉市场最具影响力品牌”。在跟风形势愈演愈烈的微波炉市场,海尔微波炉牢牢把握行业的制高点,通过细化消费需求,用最具创新性的产品和优质的服务打造了良好的品牌形象。面对微波炉行业以价格战为手段的营销方式,海尔微波炉摆脱传统模式,主打技术牌,先后推出了转波、蒸汽、智能等技术亮点,用差异化的产品满足了不同市场层面的需求。海尔微波炉率先在国内研发出了全球第四种微波炉—蒸汽转波炉,它以先进的第四代微     

微波炉

随着人们工作节奏加快、生活质量提高,微波炉以省时、省力、方便、卫生的特点,成为百姓家厨房里不可缺少的小家电。在家电卖场里,我们发现目前微波炉市场主要有格兰仕、LG、海尔、美的、松下这五个品牌,而格兰仕无疑是一     

Microwave medical devices

This article describes several new microwave medical devices that either were or are being developed at MMTC, Inc. in cooperation with the following institutions: Celsion Corporation, Columbia, Maryland (microwave balloon catheters); Montefiore Medical Center (MMC), Bronx, New York (microwave balloon catheters, dual microwave antennas, and microwave poration); and the University of California at San Francisco (conformal array antennas). The individuals who developed these devices have previously published patents and articles that contain most of the material presented here. All of the medical devices described depend on the ability of microwaves to deeply penetrate into living tissues. The depth to which microwaves can penetrate tissues is primarily a function of the dielectric properties of the tissues and of the frequency of the microwaves. In general, the lower the water content of the tissue, the deeper a wave at a given frequency can penetrate. Also, at the frequencies of interest, the lower the frequency, the deeper is the depth of penetration into tissues with given water content     

Microwave connector characterization

Coaxial connectors can be used either to probe the electrical properties of microwave circuits (e.g., microstrip, stripline) or as a permanent interface to the circuit. When used as a permanent interface, connectors can degrade circuit performance unless their electrical properties are characterized and accounted for during circuit design. Although it is more common to characterize microwave devices using scattering parameters (Collin, 1966) S_ij, we have chosen to utilize impedance parameters since they simplify the derivation of equations presented in this article. The proposed measurement-based method for connector characterization is exact in the sense that its theoretical foundation uses no approximations or assumptions     

微波硫灯

无板硫灯是一种新型电光源,它具有高发光效率、长寿命、类似太阳光的连续兜诺、无汞、小的辐射体积和容易维护等优点。该文简要介绍微波硫灯的工作原理。设计参数、设计技术和发展前景。     

Microwave Dielectric Mechanism Studied by Microwave Near-Field Microscopy and Raman Spectroscopy

Microwave dielectric ceramics such as Ba(Mg_1/3Ta_2/3)O₃ and Ba₂Ti₉O₂₀ possess high dielectric constant and low dielectric loss in microwave frequency regime and have tremendous potential for device applications. In these materials, the presence of extrinsic defects, such as secondary phases, usually altered the microwave dielectric properties of the materials markedly, but the correlation of the microwave dielectric response of the materials with their microstructure has not been fully understood due to the lack of dielectric response in the local area. In this article, microwave near-field microscopy and Raman spectroscopy were used to investigate the microwave dielectric mechanism, viz. we measured the microwave dielectric properties of the materials in micron region by using a evanescent microwave probe (EMP) and, at the same time, examined the lattice vibration characteristics of the region by using a micro-Raman spectrum. How the presence of the secondary phase affects the microwave dielectric properties of the materials is thus systematically investigated. The causes of intrinsic or extrinsic dielectric loss were explored by comparing the dielectric images in SEMP at microwave frequencies and the corresponding Raman Spectra.     

微波中继通信无源转接技术在柳林微波电路中的应用

论述了微波中继通信无源转接电路设计需考虑的一些问题及计算方法 ,并介绍了山西柳林微波电路使用无源转接技术的实际应用情况     

Microwave bytes- Squaring Up

This assumption seems to underpin not just microstrip design, but really the whole of transmission line theory as we know it, certainly as we were always taught it. The author assumes that the cross-sectional dimensions of any transmission line are negligible, not just in comparison to its length, but essentially to a wavelength as well. Transmission line theory only applies when the line is "long and thin." In conventional practice, this means it is actually quite restricted in the range of characteristic impedances that is used. The restriction applies as well, of course, to the height or substrate thickness, but in this case our basic electromagnetic (EM) theory is at least able to stipulate and even quantify the hazards of allowing higher-order waveguide modes to propagate     

形形色色的微波炉产品

微波炉是当今备受欢迎的家电产品之一,其产量、品种和普及率日增,本文介绍国内外形形色色的微波炉。     

大功率微波铁氧体材料

简要介绍了大功率微波铁气体材料的设计原理及反采取的技术措施。人出了Ｄｙ：ＹＧｄＩＧ的主要实验结果以及实型材料的性能和使用情况。     

The European Microwave Week 2008 and Its Microwave Conferences [Transnational News]

Under the auspices of the European Microwave Association (EuMA) the 11th annual European Microwave Week was organized in the Amsterdam RAI Congress Centre, The Netherlands, 27-31 October 2008. This major event consisted this year of five conferences, an exhibition, and various side events. The 38th European Microwave Conference (EuMC), the Third European Microwave Integrated Circuits Conference (EuMIC), the Fifth European Radar Conference (EuRAD), and the First European Wireless Technology Conference (EuWiT) were complemented by the Military Radar Conference 2008. The latter was organized by Defence IQ in London and collocated with the Microwave Week for the fi rst time by invitation of the EuMA and the local organizers. The Military Radar delegates were invited to participate in EuRAD.     

磁性不锈钢409L合金吸波材料的电磁与吸波性能

针对现有磁性金属吸收剂耐腐蚀性能不足的问题,以不锈钢409L粉为吸收剂、硅胶为基体制备了不同吸收剂含量的吸波材料,采用HP8722ET矢量网络分析仪对其电磁与吸波性能进行了研究。实验结果表明,在2~18GHz范围内,随着频率的增高,磁性不锈钢409L/硅胶吸波材料的介电常数实部(ε′)基本保持不变;介电常数虚部(ε″)不断增大;而磁导率的实部(μ′)和虚部(μ″)不断减小。随着409L合金吸收剂含量的增大,ε′、ε″和μ″不断增大;μ′在低频时随着体积含量的增加而增大,在高频却相反;3mm厚吸波材料最小反射率先减小后变大,吸收峰由高频向低频移动,半高宽逐渐变窄。409L体积分数为20%时,最小反射率为-17.8dB,其对应的峰值频率为9.4GHz,有效带宽(≤-8dB)达到5.27GHz(7.03~12.3GHz);体积分数为30%时,最小反射率为-24.1dB,其对应的峰值频率为6.3GHz,有效带宽(≤-8dB)达到4.5GHz(4.2~8.7GHz),在X和C波段具有较好的吸波性能。而且通过对材料进行二层设计,能够有效地进行宽频吸收,具有一定的应用前景。     

Microwave surgery inside the heart

In recent years, a revolution has taken place in cardiology to bring forth a new, minimally invasive interventional procedure: microwave transcatheter ablation for cardiac arrhythmias. The development of cardiac ablation using microwave energy was reported in 1987, the same year that the initial clinical use of RF energy for the ablation of cardiac arrhythmias appeared. However, clinical trials of microwave cardiac ablation did not take place until recently. Thus, microwave cardiac ablation is a relatively new concept for clinical treatment of cardiac arrhythmias.