打呼噜也是病

打呼噜的病人以前认为是睡的香，但现在人们已经逐渐认识它可能是一种病态。打鼾的人时常被别人抱怨，和同室或者配偶的关系变得异常紧张，令打鼾者烦恼。然而打鼾更大的危害是引起呼吸暂停．。打鼾者的气道比正常人狭窄，严重时气道可以完全阻塞，发生呼吸暂停，呼吸暂停时气体不能进入肺部，造成体内缺氧和二氧化碳潴留。严重者可导致高血压，心脏病，心律失常，脑血管意外，糖尿病，肾病，甲状腺机能减退等等，甚至发生睡眠中猝死。打鼾者的气道通常比正常人狭窄，白天清醒时咽喉部肌肉代偿性收缩使气道保持开放，不发生堵塞。但夜间睡眠时神经兴奋性下降，肌肉松弛，咽部组织堵塞，使上气道塌陷，当气流通过狭窄部位时，产生涡流并引起振动，从而出现鼾声，     

山东招远乡镇标准种植描绘绿色农业新画卷

沿着215省道一路向南，跨过306省道，最终向东拐进山东招远毕郭镇官地洼村，顿时，蓝莹莹的苍穹下，那一望无际的白色温室大棚映入记者眼帘，而一直连接到田间地头的灌溉管道阀门正喷涌出清澈无污染水源的井水，顺着水流，走进大棚中，满棚的春色扑面而来，遍地的大甜瓜、西瓜秧绿意盎然，一派生机勃勃。这里，只是山东招远毕郭镇标准化绿色农业产业结构调整的一个示范点，     

保定市北方特种气体有限公司4．5N高纯乙硼烷全杂质分析方法研发成功

2010年9月，保定市北方特种气体有限公司经过一年的实验，成功研发高纯乙硼烷中的O2，N2，CH4，C2H6，CO，CO2，CH3Cl的分析方法，     

多彩童年——儿童摄影专题——孩童世界

成长的岁月像流水，匆匆而来，匆匆而去。那时的他们，刚入学。心怀对新环境的恐惧和对父母家人的依恋，每天上午到园必有一哭，我哭，你哭，他哭，大家相互感染；也有胆大不哭在一旁看热闹的。每每这时，纠心的是家长，忙碌的是老师，左手抱一个，右手抱一个，身边还得靠两个，哄完这个亲那个……     

因地制宜 营建温馨家园——包头市丽月湾住宅小区规划与建筑设计

包头市丽月湾住宅小区位于包头青山区，处于包头市北侧，该地块东南方为包头市昆都仑区，西南方为包头市老城区青山区。地块北邻文化路，与包头市国宾馆隔路相望，北侧和小区紧邻的是迎宾花园的绿化带，南侧为市煤气公司，地块东邻包头市迎宾道，西邻民族东路，民族东路为包头市过境公路，与101国道相接，交通便利，是包头市面向外界的最前沿，小区总用地11．55公顷。     

智慧能源正在向我们走来

应IEEE 1888工作组组长刘东先生之约，让我为他们将要出版的一本书写篇序言。我知道，凡作序题跋者，差不多均为大家名家，量自己一介布衣，焉敢胡来？可是刘东先生不依不饶，他拿出三重理由规劝我。其一，他说此书讲的是标准，这是你的本行，不该推辞；其二，他说此书与节能减排有关，是你现在正做着的事，没有推托理由；其三，他说此书涉及的是互联网应用创新，你一定感兴趣。他说的这三条句句在理，不容分辩，我虽然有些心动，可还是觉得自己才疏学浅，仍未轻易点头。接下着他又补充说了一条，算是激将法吧。他说，你是否承认互联网改变一切？我点头称是。于是，他笑眯眯地接着说，那就请你改变一下自己吧！知识分子就是知识分子，显然，我在不知不觉中中了他的招。话已出口，不好再申辩。于是，就有了下面这篇称不上序言的序言。     

虚假新版发票现身广州

近日，随着杭州市加入了全国城市工商打假联盟，目前，加盟全国工商联盟打假的城市也达到15个。这些城市分别是杭州，广州、厦门，深圳，大连，哈尔滨，武汉、沈阳，长春，宁波，济南，青岛，南京、西安和成都。这15城构建起了跨城市的执法维权网。并突破了异地打假维权的难题。据了解，根据15城市的“打假协作网络”协议，     

生命与外力、生命与运动的辩证思考

一天夜里深夜醒来，无法入睡，打开电视机，正好看到的是上海复旦大学青年教师于娟和她的家人帮她与癌症作斗争的视频，故事深深地吸引和打动了我。一次骑自行车上街，一个偶然的避让，她感到骨骼疼痛难忍，到医院查出得了乳腺癌后期骨转移。于娟曾留学挪威，是父母唯一的女儿，掌上明珠。当她知道自己得了绝症之后，唯一的希望就是能够活下来有一个完整的家，父母能有女儿，丈夫能有妻子，一岁多的儿子能有母亲。在此后的一年多时间里，她和丈夫、父母共同努力，以顽强的毅力与疾病抗争，他们卖掉了房子用于治疗疾病，后来，她父母又卖掉了老家的房子用作治疗费用。     

让弱差生也能学好高中物理

近几年来，我校教师和学生严重流失，使我校的生源质量下降，我校招生的学生大多是中考失败的学生，他们在初中时学习成绩较差，已丧失了学习的自信心和积极性，一般都有厌学的情绪，物理学又是一门较难学的学科，作为一名高中物理教师，如何让这些弱差生也能学好高中物理呢？一、注重情痦交流，建立良好的师生关系常言说：喜欢一门学科，是从喜欢这个老师开始的，这话不无道理。作为一名合格的人民教师，必须有博大的胸怀，无私的爱心，在学习和生活上对“学差生”加以关注，用发展的眼光去看待他们，把一颗赤诚的爱心倾注给他们，多方面的了解、关心他们的冷暖，察颜观色。及时找他们谈心，掌握更多情况，做到心中有数，无论什么样“学差生”，只要同他们打成一片，给予一定的关怀，一同学习，一同活动，让他们知道给予他们温暖，他们就自然而然地敞开心扉，消除戒备心理，从而使学生从喜欢老师到喜爱学物理。     

浅析夏季农村防火工作的有效预防

农村，乡镇历来都是火灾防御的薄弱环节，由于乡镇距离消防队较远，缺乏消防水源，建筑耐火等级偏低，电气线路敷设不规范，防火间距不符合求的因素存在，特别是夏季炎热，天干物燥，电、气，油的大量使用导致火灾不安全因素不断增多。夏季农村防火工作的有效预防，迫在眉睫。结合实际工作，笔者认为加强农村夏季防火工作，主从以下几个方面入手。     

Prediction of Thermodynamic Properties of Liquid Air

In this work, a simple equation of state (EoS) has been used to predict some thermodynamic properties of air as a pseudo-pure fluid; as a ternary mixture of nitrogen, oxygen, and argon; and as a binary mixture of nitrogen and oxygen at different temperatures and pressures. A comparison with literature tabulated values has been made. The agreement of calculated densities with corresponding tabulated values is good for which the average absolute deviations are better than 0.06% if we assume air as a pseudo-pure fluid, and 0.9% and 1.2% if we consider air as a ternary mixture and as a binary mixture, respectively. To show the ability of this equation of state to predict density, the calculated densities of air have been compared with those computed by other methods.     

任意旋转壳的振动特性计算

本文由旋转薄壳的基本方程导出了一组等效的一阶微分方程,并采用离散变量法对其进行求解。对于子午线出现尖角及双层旋转壳相耦合的情况,推导了相应的计算公式。文末给出了算例。     

Analysis of the sensitivity properties of a model of vector-borne bubonic plague.

Model sensitivity is a key to evaluation of mathematical models in ecology and evolution, especially in complex models with numerous parameters. In this paper, we use some recently developed methods for sensitivity analysis to study the parameter sensitivity of a model of vector-borne bubonic plague in a rodent population proposed by Keeling & Gilligan. The new sensitivity tools are based on a variational analysis involving the adjoint equation. The new approach provides a relatively inexpensive way to obtain derivative information about model output with respect to parameters. We use this approach to determine the sensitivity of a quantity of interest (the force of infection from rats and their fleas to humans) to various model parameters, determine a region over which linearization at a specific parameter reference point is valid, develop a global picture of the output surface, and search for maxima and minima in a given region in the parameter space.     

Analysis of the Accuracy of Methods for the Direct Measurement of Emissivity

Emissivity measurements are of great interest for both theoretical studies and technological applications. Emissivity is a property that specifies how much radiation a real body emits as compared to a blackbody. The emissivity determination of a sample should be an easy task: a simple comparison between the sample and blackbody radiation at the same temperature. Unfortunately, when measuring the emissivity, some practical problems arise due to the differences between the true emitted radiation and the detected quantity. To clarify this point, an analysis of different direct methods for emissivity measurement is presented. Furthermore, a method that includes multiple reflections is developed. The systematic errors associated with each method are computed theoretically as a function of wavelength, sample temperature, and emissivity, and the surrounding enclosure temperature and emissivity. In general, the error is very high for small sample enclosures, but it strongly decreases when the enclosure area increases. Although at short wavelengths all the analyzed methods produce similar errors, noticeable differences appear under other conditions, and methods considering more radiation terms do not always produce lower errors.     

Accuracy improvement of T-history method for measuring heat of fusion of various materials

T-history method, developed for measuring heat-of-fusion of phase change material (PCM) in sealed tubes, has the advantages of a simple experimental device and convenience with no sampling process. However, some improper assumptions in the original method, such as using a degree of supercooling as the end of latent heat period and neglecting sensible heat during phase change, can cause significant errors in determining the heat of fusion. This problem has been improved in order to predict better results by us. The present study shows that the modified T-history method is successfully applied to a variety of PCMs such as paraffin and lauric acid having no or a low degree of supercooling. Also it turned out that selected periods for sensible and latent heat do not significantly affect the accuracy of heat-of-fusion. As a result, the method can provide an appropriate means to assess a newly developed PCM by a cycle test even if a very accurate value cannot be obtained.     

陶瓷材料压痕韧性的统计性质

采用直接压痕法测定了钠钙硅酸盐玻璃和一种ＴｉＣ 颗粒增强Ａｌ_２Ｏ_３复合材料的断裂韧性．研究表明,在同一压痕压制荷载下测得的同一种材料的压痕韧性呈现出较大离散性,可以采用Ｗｅｉｂｕｌｌ分布加以较好地描述．对两种材料的试验数据的对比分析指出,压痕韧性测试值的离散性反映了材料显微结构的不均匀性对材料局部裂纹扩展阻力的影响．基于这一分析,本文建议采用直接压痕法测定材料断裂韧性时,应尽可能增大试验量,从而对压痕韧性测试结果的统计性质作出完整描述．     

Development of a Magnetic Suspension Densimeter and Measurement of the Density of Toluene

The development of a magnetic suspension densimeter that has been built for measurement of the density of compressed liquid at pressures up to 30 MPa in the temperature range 20 to 150°C is described. The densimeter was first built by the author and his coworkers at NIST. We describe here further improvements made on a second system built at NMIJ based on the same principle. The densimeter uses a small coil suspended from an electronic balance. Within the coil is placed a sample cell in which the pressurized sample and a buoy, which is a permanent magnet, are enclosed. For measurement of density, balance readings are recorded (1) with the buoy at rest and (2) with the buoy in magnetic suspension. The measurement procedure is basically a hydrostatic weighing, which is simpler than those of conventional magnetic densimetry. As an example, measurements of toluene density performed as part of an inter-laboratory comparison are presented. The data agreed with reliable literature values to within a few hundredths of a per cent.     

Recent development and prospect of electromagnetic processing of materials

Application of electromagnetic force to materials processing, so called Electromagnetic Processing of Materials (EPM) has been recognized as a cutting edge technology, especially in the fields of advanced materials processing. The backgroundto promote EPMis described. The present state of EPMis given through a brief introduction of several examples of the applications of a high frequency magnetic field, a DC magnetic field, DC magnetic and electric fields, and a traveling magneticfield. Furthermore, a high static magnetic field has been applied to generate compression waves in molten metals. As otherexamples of the application of a high static field, the crystal orientations in thin films in vapordeposition and electrodeposition processes and those in carbon fibers in a graphitization process are described. Finally the future view of EPM is revealed.     

Prediction of Performance of an Industrial Poittemill in Production of Limestone Powders

Experimental data were collected from tests using an industrial-scale high-pressure roller mill named the Poittemill grinding limestone materials for a range of parameters (such as force pressure, circumferential speed of roll, and feed size) in a Nordkalk AB plant located in Ignaberga, Sweden. These data were used to develop models of throughput, size reduction, and energy utilization with the parameters. A performance model with a correction coefficient, which has been developed, is able to describe the Poittemill throughput at various force pressures and circumferential speeds of rolls. The materials leaked beside the rolls are found to be empirically related to the circumferential speed of roll in a given force pressure. It is shown that two major parameters, force pressure and circumferential speed of roll, have an influence on the median size (d₅₀) of the ground product. Product fineness is decreased at a higher circumferential speed of roll or at a lower force pressure. The force pressure is the most dominant effect on energy utilization in the mill. The feed size used has a slight influence on the grinding results. Energy to the Poittemill for the comminution is utilized more efficiently at a lower force pressure or a higher circumferential speed of roll. Empirical models can predict the comminution characteristics with respect to the major parameters in the Poittemill system in dry mode. Product size-energy input relations have been also established, independent of the operating parameters used.     

Recent development and prospect of electromagnetic processing of materials

Application of electromagnetic force to materials processing, so called Electromagnetic Processing of Materials (EPM) has been recognized as a cutting edge technology, especially in the fields of advanced materials processing. The background to promote EPM is described. The present state of EPM is given through a brief introduction of several examples of the applications of a high frequency magnetic field, a DC magnetic field, DC magnetic and electric fields, and a traveling magnetic field. Furthermore, a high static magnetic field has been applied to generate compression waves in molten metals. As other examples of the application of a high static field, the crystal orientations in thin films in vapordeposition and electrodeposition processes and those in carbon fibers in a graphitization process are described. Finally the future view of EPM is revealed.