范文一:铯与水反应现象综述
铯与水反应现象综述 铯能与水发生剧烈的反应,如果把铯放进盛有水的水槽中,马上就会爆炸,所以做反应时一定要小心。甚至和温度低到-116℃的冰均可发生猛烈反应产生氢气、氢氧化铯,生成的氢氧化铯是氢氧化碱中碱性最强的。
和钠相比较,密度比水大,沉于水底;
化学性质十分活泼,与水反应剧烈,放出大量氢气。
放热反应,如果有在烧杯中反应,烧杯会非常烫 一般而言,直接爆炸。
最温和的情况应该是和冰反应,也会着起来。
发生化合价归中反应,即CsH中-1价的H和水中一个+1价的H都转化为O价,生成一个H2。
_________________
| ↓
CsH + H2O = CsOH + H2↑
|____________↑
范文二:锂钠钾铷铯与水反应 铯原子and铷原子D1、D2线光谱
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【请教】外腔可调激光器,选那一种,
最近实验室可能要买一台波长连续可调的激光器,联系了两个厂家的,一个是德国的sacher公司,另一个是美国的New focus公司
我们需要的规格大概是中心波长780,800nm左右,调谐范围20nm,功率10,20mW,输出功率在整个调谐范围内基本不变。
两个公司相中的型号分别是
1
sacher : http://www.sacher-laser.com/littman.php http://www.sacher-laser.com/lmnspecs.php http://data.sacher-laser.com/LMN/ln082020.pdf
New focus:
http://www.newfocus.com/product/model.cfm?productlineid
=1modelgroupid=1120modelno=TLB%2D6312
以我自己非专业的眼光仔细比较了一下,发现两个公司的产
品基本上相当,而售价前者为1W欧元多,后者是2W美刀。
new focus的好像更有名些,国外的同行也推荐的是这个,
技术支持也相当到位,我把他们网站上提供的mannual看了
看,学到不少东西,好像他们的激光器的计算机接口也做的
蛮全。但与sacher的lion系列比,他们的velocity系列控制
面板简陋许多,唯一吸引人的就是可以实时显示工作波长,
而这个好像sacher的不行。而sacher的不仅便宜一些,而
且看起来控制面板相当专业,感觉可以自己定制的激光器工
作参数比较丰富,体现出德国人工作严谨认真的风格,但从
他们的网站上,我也没能获得关于该激光器更深层次的信
2
息,觉得很没底,不知道究竟怎么样。
我们决定在12月份定下来一台,不过现在两个好难选择,有没有比较了解这两个公司产品的朋友能够给点参考意
见, 万分感谢,比较急,谢谢大家指教了~~
我认为,还是Sacher的比较好一点,因为光机所用到现在正在打算购置新的波段的;Sacher是专门做这个的~Newfocus在其他很多方面比较有名气,而且他的产品也很好,但是做外腔可调激光器不是Newfocus的专长;一孔之见....
这个东东市场太小了,而且操作要求技术高一些,也就那几个公司做。你想用的爽,就用Newfocs,你想用的合算,就用Sacher.你要是胆子大,你就用其他品牌的吧。
Caesium Spectroscopy - D1 Line
Caesium is a very reactive alcali metal of the first group of
the table of elements. It was first discovered by Bunsen and
3
Kirchhoff in 1860 using spectroscopic investigations. It is characterized by one valence
electron.
The spectra show the saturated absoption of the D1 line of Caesium at 895nm. The spectra are detected with a continuous scan with a Sacher Lasertechnik tunable diode laser system.
Caesium is a very reactive alcali metal of the first group of the table of elements. It was first discovered by Bunsen and Kirchhoff in 1860 using spectroscopic investigations. It is characterized by one valence electron.
The spectra show the saturated absoption of the D2 line of Caesium at 852nm. The spectra are detected with a continuous scan with a Sacher Lasertechnik tunable diode laser system.
4
Rubidium Spectroscopy - D1 Line
Rubidium is a very reactive alcali metal of the first group of the table of elements. It was first discovered by Bunsen and Kirchhoff in 1861 using spectroscopic investigations. Due to its typical red color of the spectral lines it was named after the Latin word 'rubidus' (darkred). It is
characterized by one valence electron. The natural abundance of Rubidium isotopes is Rb(72.2%) and
Rb(27.8%). 8587
The spectra show the saturated absoption of the D2 line of Rubidium at 795nm. The spectra are detected via one continuous scan with a Sacher Lasertechnik tunable diode laser system.
Rubidium Spectroscopy - D2 Line
Rubidium is a very reactive alcali metal of the first group of
5
the table of elements. It was first discovered by Bunsen and Kirchhoff in 1861 using spectroscopic investigations. Due to its typical red color of the spectral lines it was named after the Latin word 'rubidus' (darkred). It is characterized by one valence electron. The natural abundance of Rubidium isotopes is Rb(72.2%) and
Rb(27.8%). 8587
The spectra show the saturated absoption of the D1 line of Rubidium at 780nm. The spectra are detected with a continuous scan with a Sacher Lasertechnik tunable diode laser system.
Electromagnetic Induced Transparancy (EIT)
Electromagnetic Induced Transparency (EIT)
Electromagnetic Induced Transparency (EIT) in a
three-level ladder-type Doppler-broadened medium, paying
6
special attention to the case where the coupling and probe beams are counter propagating and have similar frequencies as to reduce the Doppler width of the two photon process.
The pumping laser of wavelength 775.76nm couples the upper transition from state 5P3/2, F=4 (state |2>) to state 5D5/2, F=5 (state|3>) and the probe wavelength of 780nm couples one hyperfine transition of state 5S1/2, F=3 (state|1>) to state 5P3/2, F=4 (state|2>) which is the Rubidium D2 line, Review Min Xiao et. al, Phys. Rev. A51, 576-584 (1995) for therory and experimental setup.
The data show the experimental results for Rubidium vapor at room temperature. The violet curve shows the Doppler broadened Rubidium D2 spectrum determined via a low power laser system as reference. The yellow curve shows the EIT signal. The position of the EIT dip can be adjusted via the wavelength of the pump laser.
7
8
范文三:铯
铯(Caesium )·Cs ·55
IA 族,原子量132.9,体心立方晶体
高二(1)陈正昊
铯是一种非常柔软、延展性很强的的白色金属,其莫氏硬度(一种利用矿物的相对刻划硬度划分矿物硬度的标准) 在所有的元素中最低,熔点为28.4℃,接近室温的条件下为液态。
汞是唯一的熔点低于铯的金属元素。
沸点仅有641℃,铯的化合物燃烧时具有蓝色或紫色。
铯可以和除锂之外的碱金属混合形成合金,并且摩尔比例为41%铯,47%钾以及12%钠的合金的熔点为-78℃,在所有已知的金属合金中熔点最低 CsHg2为黑色并具有紫色金属光泽,而 CsHg
具有金色,同样具有金属光泽。
铯具有高度的活性,非常容易自燃。在空气中能够自发燃烧外,在很低温度下就能与水发生爆炸性反应,比碱金属中的其他元素更剧烈。铯可以在温度低达-116℃的条件下与冰发生反应。铯通常在矿物油等的干燥的饱和烃中储存和运输。必须在惰性气体的保护下处理铯。然而,铯-水的爆炸威力通常比同样量的钠-水的威力小,这是由于铯在接触到水的时候立即爆炸,聚集氢气的时间很少。 2Cs+2H2O→2CsOH+H2↑
铯的化学性质与其他碱金属类似,但是更接近于其上面的铷的化学性质。其通常的化合价为+1。铯是电正性最强的化学元素。
注:电正性是指元素脱去电子成为阳离子的难易度
Cs+的盐通常无色,除非阴离子有颜色。 许多具有潮解性,铯的乙酸盐、碳酸盐、卤化物、氧化物、硝酸盐和硫酸盐可溶于水。 复盐通常溶解度较小,硫酸铝铯溶解度较小的性质常用来从矿石中提纯铯。
氢氧化铯(CsOH )是一种具有强烈吸水性的强碱。它能迅速腐蚀半导体材料(例如硅)表面。过去化学家曾认为CsOH 是“最强的碱”,因为Cs+与OH-的相互作用很微弱。但是许多无法存在于水溶液中的化合物的碱性远比CsOH 强,例如正丁基锂和氨基钠。
铯与金的化学计量1:1的混合物加热后可以反应形成黄色的金化铯。这里的金阴离子表现为拟卤素。该化合物能够与水发生剧烈反应,生成氢氧化铯、金属金以及氢气。
注:拟卤素是一种二元无机化合物,通式为 XY , X 可以是氰基、氰氧基、硫氰基等官能基, Y 可以是上述的物质或是卤素原子。
氟化铯(CsF )是一种易潮解的白色固体,经常用于有机氟化学中作为氟离子的来源。氟化铯具有石盐结构,也就是Cs+和F?以和氯化钠中的Na+和Cl?相同的方式堆积成立方紧密堆积阵列。值得注意,铯和氟在所有已知的元素中分别具有最高和最低的电负性。
氯化铯以简单立方晶系结晶。氯原子位于立方的顶点上,而铯原子位于立方中央。该结构与溴化铯、碘化铯以及许多其它不包含铯离子的化合物相同。相反,大多数其它的碱金属卤化物采用氯化钠结构。采用氯化铯结构的原因是Cs+的离子半径为174 pm,而Cl?的半径为181 pm。
注:有机氟化学是研究有机氟化合物——含有碳-氟键(C-F )化合物的性质的有机化学分支。
电负性表示原子在分子中对成键电子的吸引能力。元素电负性数值越大,原子在形成化学键时对成键电子的吸引力越强。
铯可以和氧形成比其它碱金属更多的二元化合物。当铯在空气中燃烧时,主要产生超氧化铯 CsO2。氧化铯(Cs2O )形成橙黄色的六方晶体,在250℃时挥发,并且在超过400℃时分解为金属铯和过氧化铯。除了超氧化物和臭氧化铯CsO3,一些具有明亮颜色的低氧化物:Cs7O、Cs4O 、Cs11O3、Cs3O (暗绿色)、CsO 、 Cs3O2以及Cs7O2。
Cs11O3 簇合物球棍模型
首先将矿石粉碎,随后主要通过三种方式将铯从铯榴石中提取出来:酸消解、碱分解、以及直接还原。
在酸消解中,溶解盐酸(HCl )、硫酸(H2SO4)、氢溴酸(HBr )或者氢氟酸(HF )中。分离沉淀,将提纯的沉淀复盐分解,蒸发后得到纯氯化铯。采用硫酸的消解的方法将得到无法溶解的复盐铯矾(CsAl(SO4)2·12H2O )。铯矾与碳一起烘烤后转化为不溶于水的氧化铝,得到的产物通过沥滤得到硫酸铯(Cs2SO4)溶液。
将铯榴石与碳酸钙和氯化钙烘烤得到不易溶的硅酸盐和可溶的氯化铯。用水沥滤或者用氨水稀释,得到氯化铯溶液。蒸发得到氯化铯或者转变为铯矾或者碳酸铯。还可以在真空罐中使用钾、钠或者钙对矿石直接还原获得金属铯,但经济上不可行。 此外,还可以通过矿石中提纯化合物获得。真空中,重铬酸铯能和锆反应得到纯净的铯: Cs2Cr2O7 + 2 Zr → 2 Cs + 2 ZrO2+ Cr2O3。
石油勘探
目前非放射性铯的最大的用途是石油提取工业中使用的基于甲酸铯的钻井液。通过使氢氧化铯与甲酸反应制成的甲酸铯。甲酸铯盐溶液的密度很高,达2.3 g/cm3,减少了钻井液中有毒的高密度悬浮固体的需求。相对来说甲酸铯不会破坏环境,可以循环使用。
原子钟
美国海军天文台中的原子钟。
FOCS-1, 位于瑞典的连续冷铯原子喷泉原子钟,
于2004年开始工作,其精度为3000万年一秒
钟。
铯原子钟观察铯-133原子
的超精细结构产生的电磁辐射,
并以此作为参考点。
1955年,第一个精确的铯原子钟由路易斯·艾森在英国国家物理实验室建成。这些钟测量频率的精度为2-3×10-14,相当于时间测量的精度为每天2纳秒,或者140万年1秒。目前最先进的铯原子钟的精度超过了10-15,这意味着从6600万年前恐龙灭绝的时代起其误差仅为2秒钟,被认为是“人类目前所达到的最精确的单位实现”。
离心液
由于其密度较高,氯化铯、硫化铯、以及三氟乙酸铯通常在分子生物学中用于密度梯度离心操作。该技术主要用于分离生物样本中的病毒颗粒、细胞器以及核酸。
核应用与同位素
铯-137是一种常见的作为伽玛射线发射源的同位素。其优势在于它的半衰期大约30年,可以通过核燃料循环获得,并且最终产物钡-137是一种稳定的同位素。铯-137已经被用在农业、癌症治疗、食品消毒、污水污泥处理以及外科手术设备中。
起初研发使用铯或者汞的的静电离子推力
器的示意图
离子火箭
为了探索宇宙,必须有一种崭新的、飞行速度极快的交通工具。一般的火箭、飞船都达不到这样的速度,最多只能冲出地月系;只有每小时能飞行十几万公里的“离子火箭”才能满足要求。
铯原子的最外层电子极不稳定,很容易被激发放射出来,变成为带正电的铯离子,所以是宇宙航行离子火箭发动机理想的“燃料”。铯离子火箭的工作原理:发动机开动后,产生大量的铯蒸气,铯蒸气经过离化器的“加工”,变成了带正电的铯离子,接着在磁场的作用下加速到每秒一百五十公里,从喷管喷射出去,同时给离子火箭以强大的推动力,把火箭高度推向前进。
计算表明,用这种铯离子作宇宙火箭的推进剂,单位重量产生的推力要比使用的液体或固体燃料高出上百倍。这种铯离子火箭可以在宇宙太空遨游一二年甚至更久!
参考资料
1. N.N 格林伍德等 .元素化学 :科学出版社 ,1984 .
2. 吴建江 .金属铯的几种制取方法 :新疆有色金属 ,2012 .
3. 郑德 .铯的发现过程及其应用 :冶金工业出版社 ,1999 .
4. 中国大百科全书出版社 .《中国大百科全书》第二版 :中国大百科全书出版社 ,2009年4月 .
5. 张青莲 .无机化学丛书 :科学出版社 ,1987 .
6. 辐射小知识 - 什么是铯137?(铯) .天文台香港 [引用日期2013-09-3] .
7. 王科志 .化学工业制备手册(新) :化工出版社 ,2010 .
8. 王载兴 .无机化学实验 :高等教育出版社 ,1995 .
题文
铯的原子序数为55,是第六周期IA 族元素,试推断下列内容:
(1)铯的原子核外共有层电子,最外层有
(2) 铯跟水起剧烈反应,放出同时生成的溶液使石蕊显色,因为 (3) 碳酸铯的水溶液使酚酞显因为
(4)同位素138Cs 原子核里有个中子。
(5)原子序数为54的元素位于元素周期表中第族。因为从原子结构来看,。
答案
(1)6 1
(2)氢 蓝 生成的氢氧化铯是碱
(3)红 CO 3水解造成溶液呈碱性 2-
(4)83
(5)五 零 它的原子核外有5层电子,最外层有8个电子
范文四:298.15 K时斯蒂芬酸钾盐和铯盐在水和DMF中的溶解热
298.15K 时斯蒂芬酸钾盐和铯盐在水和 DMF 中的溶解热
刘
影
佟文超
杨
利 *
张同来
冯长根
(北京理工大学爆炸科学与技术国家重点实验室 , 北京 100081)
摘要 :
在 298.15K 时 , 采用微热量热仪测定斯蒂芬酸钾盐 [K2(TNR)(H2O)]n 和斯蒂芬酸铯盐 [Cs2(TNR)(H2O) 2]n
两种含能配合物在水和 N , N -二甲基甲酰胺 (DMF)溶剂中的溶解热 , 研究其溶解过程和溶解热化学性质 . 结果表 明 , 两种配合物溶解于水是吸热过程 , 而溶解于 DMF 则为放热过程 , 这主要是由于溶质和溶剂的分子结构及其 极性不同而导致的 . 通过对实验数据计算拟合 , 求得这两种配合物的溶解焓 (Δsol H ) 、 相对表观摩尔焓 (ФL i ) 、 相对 偏摩尔焓 (L i ) 及稀释焓 (Δdil H 1,2) 的经验公式和标准溶解焓值 (Δsol H m ). 关键词 :
溶解过程 ; 热化学 ; 斯蒂芬酸 ; 溶解焓 ; 稀释焓
中图分类号 :
O642
Solution Heat of Potassium Styphnate and Caesium Styphnate in Water
and DMF at 298.15K
LIU Ying
TONG Wen-Chao
YANG Li *
ZHANG Tong-Lai
FENG Chang-Gen
(State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, P . R. China ) Abstract:The dissolution and thermochemical properties of potassium styphnate [K2(TNR)(H2O)]n and cesium styphnate [Cs2(TNR)(H2O) 2]n in water and N , N -dimethylformamide (DMF)at 298.15K were studied by calorimetry. The processes are endothermic in water, and exothermic in DMF because of the different molecular structure and polarity of the solutes and solvents. Empirical formulas for the solution enthalpies (Δsol H ), relative apparent molar solution enthalpies (ФL i ), relative partial molar enthalpies (L i ), and dilution enthalpies (Δdil H 1,2) are deduced by polynomial expressions, and standard solution enthalpies (Δsol H m ) are also calculated. Key Words:
Dissolving process; Thermochemistry; 2,4,6-Trinitro-resorcinol; Solution enthalpy;
Dilution enthalpy
[Article]
doi:10.3866/PKU.WHXB201212202
www.whxb.pku.edu.cn
物理化学学报 (Wuli Huaxue Xuebao ) Acta Phys. -Chim. Sin . 2013, 29(3),467-472
March Received:November 16, 2012; Revised:December 17, 2012; Published on Web:December 20, 2012. ?
Corresponding author. Email:yanglibit@bit.edu.cn;Tel:+86-10-68918038.
The project was supported by the Science and Technology Fund on Applied Physical Chemistry Laboratory, China (9140C3703051105,9140C370303120C37142) and State Key Laboratory of Explosion Science and Technology, China (QNKT12-02,YBKT10-05).
应用物理化学实验室科技基金 (9140C3703051105,9140C370303120C37142) 与爆炸科学与技术国家重点实验室基金 (QNKT12-02,YBKT10-05) 资助项目
? Editorial office of Acta Physico-Chimica Sinica
1Introduction
2,4,6-Trinitro-resorcinol (TNR)is known as styphnic acid. 1Its metal salts, particularly lead styphnate and barium styph-nate as important explosive materials 2-5have been widely ap-plied to war industry. However they will release serious metal-lic pollution after explosion, which is bad for people ?s health and environment. Therefore other metal styphnates were stud-ied in order to solve this problem. Then potassium styphnate [K2(TNR)(H2O)]n and caesium styphnate [Cs2(TNR)(H2O) 2]n were
synthesized, 6,7and their crystal structures 6,7are shown in Fig.1. It can be seen that the function of H 2O is not crystal water but ligand. The two salts are expected to be used in war industry due to their low toxicity and fine invariability. For further ap-plication, it is extremely essential to study all properties and pa-rameters of them. Up to now, the structures and decomposition mechanisms of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n have been extensively investigated. 8,9But no solution enthalpies for them are known.
467
Acta Phys. -Chim. Sin. 2013Vol.29
In order to know more themochemical properties of the ener-getic complexes during their dissolving processes, and increase the basic data for the thermal interrelated parameter database of energetic complexes, in this paper we researched the dissolv-ing processes and thermochemical parameters of styphnate and caesium styphnate in water and DMF. Water and DMF are im-portant solvents in synthesizing, recrystallizing, and dissolving energetic materials. The phenomenon and mechanism for dis-solving process are studied. Then the empirical formulas of so-lution enthalpies (Δsol H ), the relative apparent molar enthalpies (ФL i ), the relative partial molar enthalpies (L i ), and the dilution enthalpies (Δdil H 1,2) are all deduced. In addition, the standard molar solution enthalpies (Δsol H m ) are calculated.
2Experimental
2.1Samples
[K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n used in the experi-ment were synthesized, purified and dried according to the pro-cedures described in the literature. 8,9In order to approve the complex, elemental analysis, differential scanning calorimetry (DSC),thermogravimetry and derivativ thermogravimetry (TG-DTG),and Fourier transform infrared (FTIR)spectra were used to determine them. Elemental analyses were a Flash EA 1112full-automatic trace element analyzer. The FTIR spec-tra was a Bruker Equinox 55infrared spectrometer (KBrpel-lets) in the range of 4000-400cm -1with a resolution of 4cm -1. DSC and TG-DTG were Pyris-1differential scanning calorime-ter and Pyris-1thermogravimetric analyzer (PerkinElmer, USA), respectively. The results completely accord with the lit- erature. 8,9The purities of them were more than 99.5%.Before the experiment the compounds were dried, sifted through a 200-mesh sieve, and then kept in vacuum for 24h.
The water was deionized, twice distilled, and degassed. The electrical conductivity of deionized water is 6.25×10-8S ·cm -1. The purity of potassium chloride is spectral reagent grade. DMF was stir mixed with CaH 2, and then filtrated after one night, at last distilled under reduced pressure from 2666Pa. 10 2.2Equipment and conditions
Calorimetric measurements were performed using a C80Micro-Calorimeter (SeteramCo., France) at 298.15K. In order to en-sure the reliability of this system, we calibrated thermo-param-eters using standard indium and stannum according to joule ef-fect theory, 11-13then determined the solution enthalpies (Δsol H m ) of potassium chloride (KCl)in water at 298.15K. 14The results were listed in Tables 1and 2. The experimental value of Δsol H m ((17.201±0.052)kJ ·mol -1) agrees with recommended literature value ((17.241±0.018) kJ ·mol -1), 15and the error between the experimental value and the literature value is 0.23%.Therefore we ascertain that the system is reliable.
The reaction solution/solventwas put into the stainless steel mixing with membrane vessel, which was made of polytetraflu-oroethene (PTFE)(0.05mm thick). The volume of solvent in every experiment is 3mL. After thermal equilibration for about 1h, the membrane was torn, and the heat flow was mea-sured.
3Results and discussion
3.1Dissolving process
Fig.1Crystal structures 6,7of [K2(TNR)(H2O)]n (a)and [Cs2(TNR)(H2O) 2]n (b)
Standard material indium
stannum m /mg
191.7
165.6
Melting point in theory/K
429.748
505.078
Scanning rate/(K·min -1)
0.1
0.3
0.5
0.1
0.2
Melting point in experiments/K
429.759
429.780
428.705
504.938
505.218
Thermo-parameter b 0=-5.01999×10-1 b 1=5.44220×10-3 b 2=2.87049 Table 1Calibration of thermo-parameters
(a)(b) 468
LIU Ying et al .:Solution Heat of Potassium Styphnate and Caesium Styphnate in Water and DMF at 298.15K
No.3
[K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n are all soluble in
water and DMF. The heat flow curves of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF at 298.15K are shown in Fig.2. The curves indicate that the complexes in water are endothermic, and in DMF are exothermic for the macroscopic analysis.
For the microcosmic analysis, the dissolving processes con-sist of physical and chemical processes. 16,17The physical pro-cesses need absorb caloric to break the molecular bond for dif-fusing solute into solvent, meanwhile the chemical processes emit caloric in chemical reaction between the solute and the solvent. 18,19The physical processes are associated with molecu-lar structures and polarity of solute and solvent. 20It is well known that the polarity of water is far stronger than that of DMF. 21In order to learn about the polarity of [K2(TNR)(H2O)]n
and [Cs2(TNR)(H2O) 2]n as solutes, we adopt Gaussian 09pro-gram 22of density functional theory (DFT)to calculate molecu-lar electrostatic potential surface. At first the initial structures of them were preliminarily optimized using the basis set B3LYP/6-31G,and then the electrostatic potential of cesium (Cs)was calculated by the functional Tao-Perdew-Staroverov-Scuseria (TPSS)23and basis set LANL2DZ, while those of the other atoms were obtained using the most popular functional B3LYP 24and basis set 6-311++G(d , p ). The molecular electro-static potential distribution maps are shown in Fig.3. Positive charges are red, and negative charges are blue.
It is found that the charge distributions are all asymmetric in Fig.3, which can deduce that the complexes are polar. For the dissolving processes in DMF as an organic-polar solvent, the charges in the solutes are apt to close with those in solvent, and then the chemical salvation responses are happened with new solute-solvent molecular chemical bond. The chemical salva-tion responses take the main part in dissolving processes, there-fore the processes of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in DMF are exothermic. In Fig.3, it is also found that the charge distribution of [Cs2(TNR)(H2O) 2]n is obviously more asymmet-ric than that of [K2(TNR)(H2O)]n . Therefore the polarity of [Cs2(TNR)(H2O) 2]n is stronger than that of [K2(TNR)(H2O)]n , and the chemical salvation responses is also more drastic. Thus in DMF the heat peak of [Cs2(TNR)(H2O) 2]n is higher than that
Fig.2Curves for the heat flows of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water (A)and DMF (B)at 298.15K
(a)(b)
Fig.3Molecular electrostatic potential distribution maps of [K2(TNR)(H2O)]n (a)and [Cs2(TNR)(H2O) 2]n
(b)
Mean value of Δsol H m is (17.201±0.052)kJ ·mol -1.
m /mg3.814.184.358.188.899.20
Molar concentration/(mmol·kg -1)
51.156.158.3109.7119.2123.4
Δsol H m /(kJ·mol -1)
17.25117.13817.09417.15017.42417.151
Table 2
Solution enthalpies (Δsol H m ) of potassium chloride (KCl)
in water at 298.15
K
469
Acta Phys. -Chim. Sin. 2013Vol.29
of [K2(TNR)(H2O)]n .
The water molecules firmly combined each other by hydro-gen bonds. The hydrogen bonds are too tight to crack for the chemical salvation response with the complexes. However the molecules of the complexes are easy to be physically attracted and diffused into water because of water ?s strong polarity. So the process in water is endothermic. The molar concentration of the complexes is same, as a result the heat peaks of the com-plexes in water are nearly equal.
3.2Thermochemical parameters
We pick up six experiments with good performance as a group. The solution enthalpies of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF with different concentra-tions are shown in Table 3.
By using the empirical formula in equation (1)25and fitting the data obtained from the experiments in Table 3, the formu-las for the solution enthalpies (Δsol H ) in the solvents were achieved in Table 4.
Δsol H =A +Bb +Cb 1/2(1) where A , B , C are the regression coefficients, b is the molality of sample in the solution.
According to the formulas in Table 4, the standard solution en-thalpies Δsol H m (b =0)of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in the two solvents are obtained respectively in Table 5.
The formulas for the relative apparent molar enthalpies (ФL i ) and the relative partial molar enthalpies (L i ) were identi-fied by academic formula in equations (2-3). 26
ΦL i =Δsol H (b ) -Δsol H (b =0) (2) L i =b [
?Δsol H
]+ΦL i (3) Substituting formulas in Table 4into equations (2-3), the for-mulas of ΦL i and L i are described in Table 6.
According to the formulas in Tables 4and 6, substituting the different concentrations, Δsol H m , ΦL i and L i at 298.15K were ob-tained in Table 3. It can be seen that Δsol H m of the complexes in water are positive values. Considering the relationship between
Table 3Solution enthalpies of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF at 298.15K
Solute [K2(TNR)(H2O)]n
[Cs2(TNR)(H2O) 2]n Solvent
water
DMF
water
DMF
No.
blank
1
2
3
4
5
6
blank
1
2
3
4
5
6
blank
1
2
3
4
5
6
blank
1
2
3
4
5
6
m /mg
0.00
1.25
1.40
1.52
1.70
2.10
2.34
0.00
1.59
1.76
2.00
2.15
2.20
2.55
0.00
2.10
2.14
2.40
2.48
2.83
3.22
0.00
0.87
0.99
1.03
1.05
1.09
1.18
b /(mmol·kg -1)
0.00
1.23
1.38
1.49
1.67
2.06
2.30
0.00
1.65
1.82
2.07
2.23
2.28
2.64
0.00
1.27
1.30
1.46
1.51
1.72
1.96
0.00
5.59
6.36
6.62
6.75
7.01
7.59
Δsol H m /(kJ·mol -1)
found
-
33.76
34.04
34.34
34.73
35.77
36.54
-
-5.50
-5.65
-5.88
-6.05
-6.08
-6.42
-
29.99
30.09
30.73
31.01
31.97
33.07
-
-21.00
-21.91
-22.22
-22.37
-22.76
-23.59
calc.
37.60
33.77
34.05
34.31
34.73
35.80
36.52
-4.35
-5.50
-5.66
-5.89
-6.03
-6.08
-6.42
28.66
29.98
30.09
30.77
30.99
31.96
33.08
-34.08
-21.01
-21.89
-22.22
-22.39
-22.75
-23.59
ФL i /(kJ·mol -1)
0.00
-3.83
-3.55
-3.29
-2.87
-1.79
-1.08
0.00
-1.15
-1.31
-1.54
-1.69
-1.74
-2.08
0.00
1.33
1.43
2.11
2.33
3.30
4.42
0.00
13.07
12.18
11.85
11.68
11.33
10.48
L i /(kJ·mol -1) 0.00 -1.61 -0.688 0.0937 1.32 4.26 6.13 0.00 -2.65 -2.99 -3.47 -3.78 -3.88 -4.60 0.00 6.70 6.94
8.55
9.05 11.29 13.84 0.00 7.25 4.21 3.15 2.61 1.51 -1.04
b :molality of sample in the solution; Δsol H m (found):the standard solution enthalpy by experiments; Δsol H m (calc.):the standard solution enthalpy by calculating; ФL i :the relative apparent molar solution enthalpy; L i :the relative partial molar enthalpy
Solvent water DMF
[K2(TNR)(H2O)]n
Δsol H m =37.60+6737.74b -345.54b 1/2
Δsol H m =-4.346-1118.14b +17.03b 1/2
[Cs2(TNR)(H2O) 2]n
Δsol H m =28.66+7350.42b -25.84b 1/2Δsol H m =-34.08-44201.60b +1598.14b 1/2
Table 4Formulas for the enthalpies (Δsol H m ) of solution of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF at 298.15K 470
LIU Ying et al .:Solution Heat of Potassium Styphnate and Caesium Styphnate in Water and DMF at 298.15K No.3
the concentration and the Δsol H m , one can see that the quantity of heat gradually increases as the concentration increases, therefore the processes are the endothermic reactions. On the contrary Δsol H m of the complexes in DMF are minus value, and rapidly decrease as the concentration increases. Therefore the processes in DMF are exothermic. By comparing Δsol H m of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF, the resemblance that the absolute values of Δsol H m increase as the concentration increase is found. The phenomenon indicates that the reactive degree is enhanced as the solute concentration increases. The results bring into correspondence with the dis-solving process results.
In Table 3the standard solution enthalpies obtained in the experiments approach to the calculated values, so the equations obtained are stable and reliable, though the concentration range is not extremely wide, which could provide a reference and some help for the much wider temperature application.
The formulas of the dilution enthalpies (Δdil H ) are as fol-lows in equation (4).26By combining the equation in Table 4, the experimental formulas of Δdil H for [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF are obtained in Table 7, then the variety for the enthalpies of them in water and DMF could be calculated according to those equations.
Δdil H 1,2=∑ 12A i [(b 1/22) i -(b 1/21) i ](4) 4Conclusions
The processes of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n dissolved in water are endothermic, however those in DMF are exothermic. This result is attributed to the polarity and molecu-lar structure of solute and solvent. From the molecular electro-static potential distribution maps, it is obtained that the molecu-lar structure asymmetry of [Cs2(TNR)(H2O) 2]n is more severe, and its polarity is more strong. So its heat peak of curves is higher. In water the tight hydrogen bonds go against the chemi-cal reaction between solute and solute, in the meanwhile the ex-tremely strong polarity is in favour of physical diffusion for solutes.
The empirical formulas for solution enthalpies (Δsol H ) are calculated, then the standard molar solution enthalpies (Δsol H m ), the relative apparent molar solution enthalpies (ΦL i ), the relative partial molar enthalpies (L i ), and the standard solution enthalpies Δsol H m (b =0)are obtained. The formulas are stable and reliable, which could provide a reference and some help for the much wider temperature application. Significantly, the phenomenon and the mechanism of dissolving processes, and thermochemi-cal parameters of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF are helpful to study thermal database of other energetic material in different solvents, and find appropriate solvents for synthesizing and recrystallizing new energetic crystals.
References
(1)Zhu, W. H.; Xiao, H. M. J. Phys. Chem. B 2009, 113, 10315. doi:10.1021/jp903982w
(2)Borzdun, V . N.; Dvorovenko, N. N.; Ryabykh, S. M. High Energ. Chem . 2002, 36, 438. doi:10.1023/A:1021039212037 (3)Kalaivani, D.; Malarvizhi, R. Acta Crystallogr. Sect. E:Struct. Rep. Online 2010, 66, 2698. doi:10.1107/S1600536810038304 (4)Zhang, T. L.; Lv, C. H.; Qiao, X. J.; Cai, R. J. Chin. J. Struct. Chem . 1999, 18, 432.
(5)Zheng, H.; Zhang, T. L.; Zhang, J. G.; Qiao, X. J.; Yang, L.; Yu, K. B. Chin. J. Chem . 2006, 24, 845. [郑 红 , 张同来 , 张建 国 , 乔小晶 , 杨 利 , 郁开北 . 中国化学 , 2006, 24, 845.]
(6)Li, Y . F.; Zhang, T. L.; Zhang, J. G.; Ma, G. X.; Song, J. C.; Sun, Y . H.; Yu, K. B. Chin. J. Inorg. Chem. 2003, 19, 861. [李玉锋 , 张同来 , 张建国 , 马桂霞 , 宋江闯 , 孙远华 , 郁开北 . 无机化学学 报 , 2003, 19, 861.]
(7)Zheng, H.; Zhang, T. L.; Yang, L. Chin. J. Energ. Mater . 2006, 14, 1.
(8)Burdikova, T. V .; Erzikov, S. A. Ignition Composition for Electro Igniters Comprises Potassium Chlorate, Lead Thiocyanate, Red Lead, Titanium, Barium Styphnate and Silicon Organic Lacque as Binding Agent. RU Patent 2353604-C2, 2009-04-27. (9)Baskakovy, M.; Bibnev, N. M. Percussion Cap of Cartridge of Small Arms Includes Percussion-Igniting Composition
Containing Diazodinitrophenol, Monobasic Potassium
Styphnate and Inert Sensibiliser. RU Patent 2384552-C2, 2010-03-20.
Solvent
water DMF Δsol H m ([K2(TNR)(H2O)]n )
(kJ·mol -1)
37.60
-4.346
Δsol H m ([Cs2(TNR)(H2O) 2]n ) (kJ·mol -1) 28.66
-34.08
Table 5Standard solution enthalpies Δsol H m (b =0)of solution of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and
DMF at 298.15K Solvent water
DMF
[K2(TNR)(H2O)]n
ΦL i =6837.74b -345.54b 1/2
L i =13475.476b -518.304b 1/2
ΦL i =2947.48b -97.04b 1/2
L i =5894.97b -141.06b 1/2
[Cs2(TNR)(H2O) 2]n ΦL i =7350.42b -225.84b 1/2 L i =14700.84b -338.76b 1/2ΦL i =-44201.60b +1598.14b 1/2 L i =-88403.19b +2397.22b 1/2
Table 6Formulas of ΦL i and L i of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF
Table 7Formulas of dilution enthalpies (Δdil H 1,2) of [K2(TNR)(H2O)]n and [Cs2(TNR)(H2O) 2]n in water and DMF
Solvent water DMF
[K2(TNR)(H2O)]n
Δdil H 1,2=6737.74(b 1/22-b 1/21) -345.54(b 2-b 1)
Δdil H 1,2=-1118.14(b 1/22-b 1/21)+17.03(b 2-b 1)
[Cs2(TNR)(H2O) 2]n
Δdil H 1,2=7350.42(b 1/22-b 1/21) -225.84(b 2-b 1)
Δdil H 1,2=-44201.60(b 1/22-b 1/21)+1598.14(b 2-b 1)
471
Acta Phys. -Chim. Sin. 2013Vol.29
(10)Armarego, W. L. F.; Chai, C. L. L. Purification of Laboratory Chemiscals , 5th ed.; Chemical Industry Press:Beijing, 2007; pp 100-141.
(11)Kresheck, G. C.; Vitello, L. B.; Erman, J. E. Biochemistry 1995, 34, 8398. doi:10.1021/bi00026a022
(12)Ivanov, E. V .; Abrosimov, V . K.; Smirnov, V . I. J. Chem. Thermodyn . 2007, 39, 1614. doi:10.1016/j.jct.2007.04.008 (13)Ivanov, E. V .; Smirnov, V . I. J. Chem. Thermodyn . 2008, 40, 1342. doi:10.1016/j.jct.2008.05.010
(14)Xue, L.; Zhao, F. Q.; Xing, X. L.; Gao, H. X.; Yi, J. H.; Hu, R. Z. Acta Phys. -Chim. Sin . 2009, 25, 2413. [薛 亮 , 赵凤起 , 邢晓玲 , 高红旭 , 仪建华 , 胡荣祖 . 物理化学学报 , 2009, 25, 2413.]doi:10.3866/PKU.WHXB20091129
(15)Kilday, M. V . J. Res. Natl. Bur. Stand. (U.S.) 1980, 85, 467. doi:10.6028/jres.085.027
(16)Palecz, B.; Belica, S.; Nowicka, B. Z. J. Chem. Thermodyn . 2009, 41, 923. doi:10.1016/j.jct.2009.03.002
(17)Hugues, A.; Karine, B. B.; Laurence, R.; Coxam, J. Y . J. Chem. Eng. Data 2011, 56, 3351. doi:10.1021/je2002946 (18)Smirnov, V . I.; Badelin, V . G. Thermochim. Acta 2009, 495, 90. doi:10.1016/j.tca.2009.06.005 (19)Zhang, R.; Wang, X.; Yan, W. D. Thermochim. Acta 2007, 466, 35. doi:10.1016/j.tca.2007.10.006
(20)Liu, M.; Wang, L. L.; Li, G. Q.; Dong, L. N.; Sun, D. Z.; Zhu, L. Y . J. Chem. Thermodyn . 2011, 43, 983. doi:10.1016/
j.jct.2011.02.005
(21)Michaux, G.; Reisse, J. J. Am. Chem. Soc. 1982, 104, 6895. doi: 10.1021/ja00389a002
(22)Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; et al. Gaussian 09, Revision A.02; Gaussian Inc.:Wallingford, CT, 2009. (23)Jiang, Q.; Chu, W.; Sun, W. J.; Liu, F. S.; Xue, Y . Acta
Phys. -Chim. Sin . 2012, 28, 1101. [蒋 倩 , 储 伟 , 孙文晶 , 刘凤嗣 , 薛 英 . 物理化学学报 , 2012, 28, 1101.]doi:10.3866/ PKU.WHXB201203054
(24)Fan, Y . B.; Gao, Y . Q. Acta Phys. -Chim. Sin . 2010, 26, 1034. [范育波 , 高毅勤 . 物理化学学报 , 2010, 26, 1034.]doi:10.3866/ PKU.WHXB20100447
(25)Yang, L.; Pei, Q.; Zhang, T. l.; Zhang, J. G.; Cao, Y . L.
Thermochim. Acta 2007, 463, 13. doi:10.1016/j.tca.2007.04.013 (26)Yang, L.; Xue, B.; Wang, S. S.; Zhang, T. L.; Zhang, J. G. Propellants Explos. Pyrotech. 2010, 35, 477. doi:10.1002/ prep.200800001
472
范文五:能有效捕捉溶解在水的放射性碘、铯、锶,有92 和99 97 的 吸附率
能有效捕捉溶解在水的放射性碘、铯、
锶,有92 和99 97 的 吸附率
河南造出核污染处理宝贝对碘-131吸附率达99.97%
2011年04月21日08:07:59来源:大河网-河南商报我要评论【进入论坛】分享好友这个宝贝对核放射性物质碘-131的吸附率达到了99.97%,是目前世界上最顶尖的产品
中科院院士经福谦说,河南的这个科技创新是对世界的巨大贡献,会大有作为
今天起,很多人可以松一口气了。
这些人,指的是世界各地对日本核污染担心多时的人们。
昨天,一场媒体云集的新闻发布会在郑州举办。新闻发布会上宣告,对核污染,比如对核放射性物质碘-131,河南研发的产品的吸附率达到了99.97%,为世界最高水平。这是一种什么产品?这意味着什么?
河南商报记者王海圣文/图
科技
对碘-131有99.97%的吸附效果
这场新闻发布会主题明确:核污水处理技术--催化生物陶项目落地发布会。
中国工程物理研究院院士、核物理学家经福谦,中国工程物理研究院研究员、核化学专家王和义博士,中国科学院高能物理研究所研究员张智勇博士等在发布席就座。
发布会共分为4项议程:1.张智勇代表其所在研究所和中国工程物理研究院,宣读了上述两家核权威机构出具的检测证书;2.经福谦院士发表感想;3.河南催
化生物陶项目负责人董良杰介绍相关情况;4.主办方漯河市政府常务副市长曹存正介绍项目情况。
张智勇所念的这份检测证书相当简短,但其披露的内容振奋人心。
据介绍,中国原子能科学研究院于2011年4月14日进行的检测报告显示,利用这种新材料过滤放射性高达185万贝克/升的碘-125废水,仅用5分钟的水力停留时间,放射性碘-125去除率高达92%。
而将10克催化生物陶颗粒,浸泡在含有12640贝克/升的放射性碘-131的核废水中20分钟,可吸附固定高达99.97%的放射性物质碘-131。"我想就此说两点:这是经过权威鉴定的;这是会大有作为的。"经福谦院士说。
经福谦院士表示,日本核污染举世震惊,中国的核电站因此暂停,正进行安全评审,"河南能研发出来这样的产品,这是急国家之所急,这是为世界做贡献,我很敬佩"。
评价
"这是目前世界上最顶尖的产品"
经福谦院士敬佩的另一点是:该产品对两种辐射物分别有着92%和99.97%的吸附率。
而碘-131,是最常见的核辐射污染物,也是日本福岛核事故释放最多的放射物。
研发了这种产品的是一个博士团队,其领军人物是催化生物陶技术、微鼻重金属过滤技术发明人,原美国夏威夷大学环境专家,河南天源环保高科股份有限公司技术总监董良杰。
昨天,董良杰接受河南商报记者采访时说,第一代生物陶技术是他于2002年开始研制,2004年研制成功的,2008年有了第二代产品。
2010年,在董良杰带领下,第三代生物陶技术在中国研制成功,并申请了发明专利。
说来有一点"撞大运"的成分。
董良杰介绍说,在最初,第三代生物陶技术是用于空气净化的,"3月11日,我从韩国飞往美国,得知日本发生了大地震,意识到可能会发生核泄漏,随即,我们确定了有关核污染的研发方向,也就是在原有技术基础上进行调整和更新,并最终取得了成功"。
据介绍,单是在测试上,他们就选择了天津、北京和郑州3个地点。
产品既成,有无竞争力?在北京,该团队就99.97%的吸附率咨询上述两个科研机构的专家,专家们告诉他,"这是目前世界上最顶尖的产品,没有之一。"
进展
这样的产品河南已储存10吨
资料显示,目前,类似产品已被日本方面使用。
据昨天出版的《人民日报海外版》消息,4月19日,日本研究人员宣布,他们开发出了一种能有效捕捉溶解在水中的放射性碘、铯、锶等并使之沉淀的粉末。
而这种粉末,和董良杰带领研发的这种催化生物陶技术相类。
"据测算,1公斤催化生物陶,能够定向吸附和固定38立方米海水中的碘离子。"董良杰说。
那么,河南的产品在日本使用了吗?
昨天就此接受商报记者采访时,河南天源环保高科股份有限公司董事长杨松鹤表示不方便透露。不过董良杰说,他们和日本学界有着密切的接触,近来接触更为频繁。"具体细节暂时不便公开。"
据董良杰介绍,目前这样的产品,天源公司已生产了10吨样品,随时可以使用。
而该公司投资亿元建设的一条生产线已具备规模生产能力,近期即将投产。
"这种催化生物陶颗粒的使用是相当简单和方便的,可以通过飞机空中抛撒。"董良杰说。
不只可以应用于核事故,董良杰说,该新材料的推出是一场业界的革命。比如在医院等场所,需要经常处理放射性废水,目前一般采用蒸发的方式,不但麻烦,放射性碘-131也容易挥发到空气中,"催化生物陶颗粒能保证方便、快捷和安全"。
解惑
在河南发布因为企业在河南
"这么说吧,这个产品可以广泛应用于核事故应急、核废水处理、核设施防护、医疗放射性废水处理等多个方面。"董良杰说。
这或许就是经福谦院士所说的"会大有作为"的原因。
发布会期间,杨松鹤在发布席还讲了一个插曲--决定发布"催化生物陶项目"时,相当多的人建议他们选择在北京发布。理论上,鉴于外国传媒机构的云集,这样的发布能取得更大的轰动性。不过漯河方面最终决定在河南发布。
"有3个理由:1.我们是河南的企业;2.专利申请在河南,产品诞生在河南;3.方便人们到企业参观。"杨松鹤说。
就此,董良杰补充说,在这个问题上,北京的科研权威也发表了意见,他们的意思是:"没有必要跑到北京来,这就是你们河南的嘛!是你们好几个单位一起做成的嘛!这也是河南的骄傲,对不对?"
昨天,漯河市常务副市长曹存正在发布会上说,漯河市委、市政府高度重视这一项目,将努力促使这一项目做大做强。
"中国人有办法进行核污染的控制,这是我们想传递的信息。"董良杰说。
人物名片
董良杰催化生物陶技术、微鼻重金属过滤技术发明人,原美国夏威夷大学环境专家,河南天源环保高科股份有限公司技术总监。2006年3月,他的发明专利技术:微鼻(MicroNose)饮用水脱砷及重金属技术。该技术被认为是脱重金属技术的重大突破,获得夏威夷大学技术奖和商业发展奖第一名,并被美国工程院评为15个最佳脱砷技术之一。2006年5月,他主持设计和建设的Waialee废水处理和面源污染控制工程,被美国环保总署评为成功样板工程。