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。     

Power of TATP based explosives

The power of various explosive mixtures based on triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane, TATP), ammonimum nitrate (AN), urea nitrate (UrN) and water (W), namely TATP/AN, oil/AN, TATP/UrN, TATP/W and TATP/AN/W, was studied using the ballistic mortar test. The ternary mixtures of TATP/AN/W have relatively high power in case of the low water contents. Their power decrease significantly with increasing the water content in the mixture to more than 30%.     

Application of selected-ion flow tube mass spectrometry to the real-time detection of triacetone triperoxide

A fast, efficient, real-time method for the quantitative analysis of the peroxide explosive, TATP, is described. The method utilizes rapid ion-molecule reactions of chemical reagent ions with the vapor above solid TATP. The reactions of three reagent ions (H3O+, O2+, NO+) were examined. Although all three ions exhibited a near-collision-rate reaction with TATP, only NO+ showed product ions that provide unequivocal evidence for a TATP-based explosive. The limit of detection of TATP in the gas phase is 10 ppb (4 x 10(-10) mol L(-1)).     

High-sensitivity detection of triacetone triperoxide (TATP) and its precursor acetone

Triacetone triperoxide (C(9)H(18)O(6), molecular mass of 222.24 g/mol) (TATP) is a powerful explosive that is easy to synthesize using commonly available household chemicals, acetone, and hydrogen peroxide 1 2. Because of the simplicity of its synthesis, TATP is often the explosive of choice for terrorists, including suicide bombers. For providing safety to the population, early detection of TATP and isolation of such individuals are essential. We report unambiguous, high-sensitivity detection of TATP and its precursor, acetone, using room-temperature quantum cascade laser photoacoustic spectroscopy (QCL-PAS). The available sensitivity is such that TATP, carried on a person (at a nominal body temperature of 37 degrees C), should be detectable at some distance. The combination of demonstrated detection of TATP and acetone should be ideal for screening at airports and other public places for providing increased public safety.     

TATP模拟物的设计及安全性评估

三过氧化三丙酮（TATP）直接用于安检培训具有危险性高、安全隐患多的问题。设计出可代替TATP在X光机、CT机等高通量安检仪中成像的模拟物。物质组成为m(葡萄糖)∶m(十六醇)∶m(蔗糖)=25.77∶9.68∶14.55，与TATP具有相似的外观及有效原子序数，元素质量分数相差小于0.020%，堆积密度相差0.012 g/cm³。为确保模拟物在红外、拉曼等高灵敏性安检仪中亦存在特征信号，在混合物中加入适量TATP。结果表明，当TATP的加入量为20%（质量分数）时，可有效地表征出混合物中TATP的红外、拉曼特征峰；同时，体系相容性较好，机械感度低，且不具有爆炸性。优化后的配方为:m(葡萄糖)∶m(十六醇)∶m(蔗糖)∶m(TATP）=20.62∶7.74∶11.64∶10.00。该模拟物与TATP的相似度高、安全性好，可直接用于安检人员培训。     

Some properties of explosive mixtures containing peroxides Part I. Relative performance and detonation of mixtures with triacetone triperoxide

This study concerns mixtures of triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane, TATP) and ammonium nitrate (AN) with added water (W), as the case may be, and dry mixtures of TATP with urea nitrate (UN). Relative performances (RP) of the mixtures and their individual components, relative to TNT, were determined by means of ballistic mortar. The detonation energies, E0, and detonation velocities, D, were calculated for the mixtures studied by means of the thermodynamic code CHEETAH. Relationships have been found and are discussed between the RP and the E0 values related to unit volume of gaseous products of detonation of these mixtures. These relationships together with those between RP and oxygen balance values of the mixtures studied indicate different types of participation of AN and UN in the explosive decomposition of the respective mixtures. Dry TATP/UN mixtures exhibit lower RP than analogous mixtures TATP/AN containing up to 25% of water. Depending on the water content, the TATP/AN mixtures possess higher detonability values than the ANFO explosives. A semi-logarithmic relationship between the D values and oxygen coefficients has been derived for all the mixtures studied at the charge density of 1000 kg m(-3). Among the mixtures studied, this relationship distinguishes several samples of the type of "tertiary explosives" as well as samples that approach "high explosives" in their performances and detonation velocities.     

Characterization of triacetone triperoxide by ion mobility spectrometry and mass spectrometry following atmospheric pressure chemical ionization

The atmospheric pressure chemical ionization of triacetone triperoxide (TATP) with subsequent separation and detection by ion mobility spectrometry has been studied. Positive ionization with hydronium reactant ions produced only fragments of the TATP molecule, with m/z 91 ion being the most predominant species. Ionization with ammonium reactant ions produced a molecular adduct at m/z 240. The reduced mobility value of this ion was constant at 1.36 cm(2)V(-1)s(-1) across the temperature range from 60 to 140 °C. The stability of this ion was temperature dependent and did not exist at temperatures above 140 °C, where only fragment ions were observed. The introduction of ammonia vapors with TATP resulted in the formation of m/z 58 ion. As the concentration of ammonia increased, this smaller ion appeared to dominate the spectra and the TATP-ammonium adduct decreased in intensity. The ion at m/z 58 has been noted by several research groups upon using ammonia reagents in chemical ionization, but the identity was unknown. Evidence presented here supports the formation of protonated 2-propanimine. A proposed mechanism involves the addition of ammonia to the TATP-ammonium adduct followed by an elimination reaction. A similar mechanism involving the chemical ionization of acetone with excess ammonia also showed the formation of m/z 58 ion. TATP vapors from a solid sample were detected with a hand-held ion mobility spectrometer operated at room temperature. The TATP-ammonium molecular adduct was observed in the presence of ammonia and TATP vapors with this spectrometer.     

In situ trace detection of peroxide explosives by desorption electrospray ionization and desorption atmospheric pressure chemical ionization

Desorption electrospray ionization (DESI) mass spectrometry is used for the rapid (<5 s), selective, and sensitive detection of trace amounts of the peroxide-based explosives, hexamethylene triperoxide diamine (HMTD), tetracetone tetraperoxide (TrATrP), and triacetone triperoxide (TATP), directly from ambient surfaces without any sample preparation. The analytes are observed as the alkali metal ion complexes. Remarkably, collision-induced dissociation (CID) of the HMTD, TATP, and TrATrP complexes with Na(+), K(+), and Li(+) occurs with retention of the metal, a process triggered by an unusual homolytic cleavage of the peroxide bond, forming a distonic ion. This is followed by elimination of a fragment of 30 mass units, shown to be the expected neutral molecule, formaldehyde, in the case of HMTD, but shown by isotopic labeling experiments to be ethane in the cases of TATP and TrATrP. Density functional theory (DFT) calculations support the suggested fragmentation mechanisms for the complexes. Binding energies of Na+ of 40.2 and 33.1 kcal/mol were calculated for TATP-Na(+) and HMTD-Na(+) complexes, suggesting a strong interaction between the peroxide groups and the sodium ion. Increased selectivity is obtained either by MS/MS or by doping the spray solvent with additives that produce the lithium and potassium complexes of TATP, HMTD, and TrATrP. Addition of dopants into the solvent spray increased the signal intensity by an order of magnitude. When pure alcohol or aqueous hydrogen peroxide was used as the spray solvent, the (HMTD + Na)+ complex was able to bind a molecule of alcohol (methanol or ethanol) or hydrogen peroxide, providing additional characteristic ions to increase the selectivity of analysis. DESI also allowed the rapid detection of peroxide explosives in complex matrixes such as diesel fuel and lubricants using single or multiple cation additives (Na(+), K(+), and Li(+), and NH4(+)) in the spray solvent. Low-nanogram detection limits were achieved for HMTD, TrATrP, and TATP in these complex matrixes. The DESI response was linear over 3 orders of magnitude for HMTD and TATP on paper surfaces (1-5000 ng), and quantification of both peroxide explosives from paper gave precisions (RSD) of less than 3%. The use of pure water and compressed air as the DESI spray solution and nebulizing gas, respectively, showed similar ionization efficiencies to those obtained using methanol/water mixtures and nitrogen gas (the typical choices). An alternative ambient method, desorption atmospheric pressure chemical ionization (DAPCI), was also used to detect trace amounts of HMTD and TATP in air by complexation with gas-phase ammonium ions (NH4(+)) generated by atmospheric pressure ammonia ionization.     

Trace analysis of peroxide-based explosives

The first method for quantitative trace analysis of peroxide-based explosives is described. A reversed-phase high-performance liquid chromatography method with post-column UV irradiation and fluorescence detection for the analysis of triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD) has been developed. After separation, the analytes are degraded photochemically to hydrogen peroxide, which is subsequently determined on the basis of the peroxidase-catalyzed oxidation of p-hydroxyphenylacetic acid to the fluorescent dimer. This two-step reaction scheme in combination with the respective blanks (photochemical reactor switched off) provides for high selectivity. The limits of detection were 2 x 10(-6) mol/L for both TATP and HMTD, respectively. The method has been applied to the analysis of real samples.     

Determination of peroxide-based explosives using liquid chromatography with on-line infrared detection

A nondestructive analytical method for peroxide-based explosives determination in solid samples is described. Reversed-phase high-performance liquid chromatography in combination with on-line Fourier transform infrared (FT-IR) detection is used for the analysis of triacetonetriperoxide (TATP) and hexamethylenetriperoxide diamine (HMTD). In contrast to other liquid chromatographic methods with optical detection, no derivatization or decomposition of the peroxides is required. The peroxides are identified and quantified via their characteristic absorption spectra in the mid-infrared range of the electromagnetic spectrum. The detection limit of 0.5 mmol L-1 for HMTD and 1 mmol L-1 for TATP allows the identification of the explosives in complex matrixes.     

Development of SRM 2907 trace terrorist explosives simulants for the detection of Semtex and triacetone triperoxide

Effective and accurate detection of trace explosives is crucial in the effort to thwart terrorist explosives attacks. A National Institute of Standards and Technology (NIST) standard reference material (SRM) has been developed for the evaluation of trace explosives detectors that sample by collection of residue particles using swiping or air filtration. SRM 2907 Trace Terrorist Explosives Simulants consists of two materials individually simulating the residues of the plastic explosive Semtex [for pentaerytritol tetranitrate (PETN)] and the improvised explosive triacetone triperoxide (TATP). Unique challenges were encountered in the development of these materials, including the selection of suitable inert substrates, material preparation, thermal stability testing, and analytical method development. Two independent analytical methods based on liquid chromatography with ultraviolet absorbance and mass spectrometric detection, LC-UV and LC/MS, respectively, were developed and used to certify the mass fractions of PETN and TATP. These materials were further evaluated for their suitability on a field swipe-sampled trace explosives detectors based on ion mobility spectrometry (IMS).