查询词典 bromine water

The results showed that the different mass concentration of HPAM's absorbance decreases slightly when the PH value of the buffer solution is 5.0, but its reproducibility is better;In order to make the absorbance become more stable, the reaction time was identified adding proper quantities of bromine water, sodium formate and starch-cadmium iodide reagent to the solution separately; the mass concentration curve of the HPAM was draw, by means of the straight degree of the curves, the coincidence degree of the straight line about the concentration of every sampling point and so on , it shows that the mixer has good mixed effect compared with the standard curve.

如下是一些主要问题：1）文章的行文格式。文章没有按照一般科技论文的表述方式，如1是引言，2是常用方法，其实这都应该是第一部分引言里应该介绍的，引言中应扼要介绍文章的研究背景、目的，意义，采用的主要方法等。还有3是实验装置，4是实验步骤，应该这些都是第二部分，试验材料与方法。2）文章的内容。文章应主要介绍本研究的具体内容，但是本文没有，如3 实验装置部分，这个721分光光度计的原理与论文内容联系不大，根本没必要介绍，标准曲线的研究应该放在最前面等。3）文章的表述不清。如HPAM是何物，文章一直没有介绍，什么曲线的直线度、浓度与直线的重合度、什么加入溴水后的时间，应该是反应时间，总之表述不清！ 4）文章的图表。图标绘制的很难看。如图2，应该纵坐标起始点从0.25开始，这样图形就会美观很多，图3又没有纵坐标标注，还多了一个纵坐标等。5）文章的结论。文章的结论中有些严格来说不是结论，而是实验中的现象与操作注意事项。

When having teacher and student, with the phenomenon with bromine water vitriolic and ferrous oxidation very bright

在进行教学时，用溴水氧化硫酸亚铁的现象很明

The process includes the following steps: dissolving bromine in halogenated hydrocarbon, dropping the bromine solution into reactant system comprising pentabromo toluene, halogenated hydrocarbon, free radical initiator and hydrogen peroxide at 50-65 deg.c, and heating to 60-78 deg.c for reflux reaction until the reactant system becomes transparent; filtering the resultant to obtain solid product, washing with carbon tetrachloride and water separately and vacuum drying to obtain pentabromo benzyl bromide.

具体步骤为：将五溴甲苯、卤代烃、自由基引发剂和过氧化氢组成的反应体系加入到三颈瓶中，将0.07～0.1mol的溴溶于50ml卤代烃配成溶液，在50-65℃温度下滴加到反应体系中，滴加时间为50-70分钟，然后升温至60-78℃温度下回流反应，至反应体系逐渐变透明，且不再产生气泡时，将所得产物过滤，得到固体产物，分别用CCl 4 和水洗涤，真空干燥，即得到五溴苄基溴；其中，五溴甲苯与溴的摩尔比为1∶0.7-1∶1.0，溴与过氧化氢的摩尔比为1∶1.0-1∶1.4，自由基引发剂加入量为五溴甲苯重量的1-10％，卤代烃的加入量为反应体系体积的40％-100％，所用溶剂可以直接进行下一批反应，不需要更换溶剂或蒸馏提纯。

In raising test tube, amid adds person bromine water, oscillation, what phenomenon does observation have to happen?

在其中一支试管中加人溴水，振荡，观察有什么现象发生？

Urine sample was digested with an acid mixture of H2SO4 and HNO3,and thallium ion in sample solution was oxidized to Tl with bromine water.

铊是剧毒稀有分散金属之一，尽管其在地壳中的含量低，但时有急慢性中毒的事件发生[1]，已被列入我国优先控制的污染物之一[2]。

The instrument can be used for the determination of total sulfur, total chrorine, trace water, bromine number and bromine index, mercaptan and hydrogen sulfide, chloride ion, salt content and chemical oxygen demand.

仪器可广泛用于各种样品中总硫、总氯、微量水分、溴价和溴指数、硫醇和硫化氢、氯离子和盐含量以及化学需氧量等的测定。

Methods IO(superscript - subscript 3) was prepared by quantitative oxidation of bromine water, with the excessive bromine removed with formic acid. In the presence of excessive iodide, I(superscript -) would be oxidized by I(superscript - subscript 3) to form 3 times of I(superscript - subscript 3) in mol, displaying maximal absorption at 286nm in ultraviolet zone and a slightly low apex at 345nm.ε286=1.3×10^5 Lmol^(-1)cm^(-1),ε345=8.1×10^4 Lmol^(-1)cm^(-1), with both showing high sensitivity.

利用溴水定量氧化I生成IO(上标-下标 3)，再用甲酸除去过量的溴，IO(上标-下标 3)在过量碘化物存在下氧化I产生3倍摩尔量的I(上标-下标 3)，在紫外光区的286nm具有最大吸收，并在345nm处另有一略低的吸收峰，ε286=1.3×10^5 Lmol^(-1)cm^(-1)，ε345=8.1×10^4 Lmol^(-1)cm^(-1)，均具有很高的灵敏度。

Methods Thallium was oxidized to thallium by bromine water and the thallium was complexed to [TlCl4](superscript -) in 20mL/100mL HCl and absorbed by polyurethane foam. The adsorbed thallium was eluted by a boiling Water bath and determined by platform-GFAAS.

以溴水将水样中的Tl氧化为Tl，在20mL/100mL的盐酸中Tl转化成[TlCl4]并为聚氨酯泡沫吸附，吸附的[TlCl4]经沸水浴洗脱后以平台石墨炉原子吸收法测定。

Absorption type hot pump , three-efficiency steam bromine refrigerator, two-stage hot water bromine refrigerator, tube and sheet heat exchanger bromine refrigerator, double heat source bromine refrigerator and coal fired bromine refrigerator.

介绍几种新型溴化锂吸收式制冷机，诸如吸收式热泵、三效蒸汽型溴冷机、双段热水型溴冷机、板式换热器溴冷机、双热源溴冷机和燃煤型溴冷机等。

Melting point 3410 ℃, boiling point 560 ℃, relative density of 1935, F the external electronic structure of 5d46s2, in the chemical reaction time is very easy to lose 1-6 electronic, but also can get 1-2 electronic, so oxidation number of 0,± 1,± 2, 3, 4 , 5 and 6, with 6 price of the most stable compounds, such as WO3 does not dissolve in water, the air will form in the tungsten trioxide thin protective layer of tungsten, tungsten with fluorine at room temperature, chemical combination, red hot when there is no moisture and Bromine iodide together, red hot when you can and water reaction WO3, at room temperature reaction of tungsten with aqua regia, but the hot concentrated hydrochloric acid and sulfuric acid can only be played with its weak response, but molten nitrate, nitrite, too Hydrogen peroxide, sulfur steam, steam and other phosphorus can play intense reaction, high temperature can not be carbon, boron and silicon reaction of binary compounds, widely used in industrial tungsten steel and tungsten carbide, pure tungsten filament is used to the system, and X-ray tube Tube heating components, semiconductor components can be prepared tungsten silicide, tungsten industrial production is white or black tungsten ore tungsten ore refining.

熔点3410℃，沸点560℃，相对密度1935，F外围电子结构为5d46s2，在化学反应时很容易丢掉1—6个电子，也能得到1—2个电子，所以氧化数为0、±1、±2、＋3、＋4、＋5和＋6，以＋6价化合物最稳定，如WO3不溶于水，空气中的钨会形成薄层三氧化钨保护层，钨能与氟在室温下化合，红热并无潮气时能与溴、碘化合，红热时还能和水反应生成WO3，室温下钨可与王水反应，但热的浓盐酸和硫酸只能与其起微弱反应，但对熔融的硝酸盐、亚硝酸盐、过氧化氢、硫蒸汽、磷蒸汽等能起激烈反应，高温下不能与碳、硼和硅反应生成二元化合物，工业上广泛使用钨钢和碳化钨，纯钨用来制灯丝、电子管和X射线管的发热元件，硅化钨可制半导体元件，钨工业生产是将白钨矿石或黑钨矿石精炼。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。