金属镍吸附氢同位素的量子力学计算_二_溶解度的计算方法

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氢和镍产生放热反应的原理

氢和镍产生放热反应的原理水的分解反应是将水分子(H2O)分解为氢气(H2)和氧气(O2)的化学反应。

这个反应是一个放热反应，也就是它会释放出热量。

然而，水在室温下非常稳定，不会自发地分解成氢气和氧气。

因此需要引入镍催化剂来加速反应进程。

催化剂是一种物质，它能够改变反应的速率，而自身并不参与其中，也不会被反应消耗掉。

镍是常见的水分解反应催化剂之一，其表面具有活性位点，能够吸附水分子并将其分解。

当水分子接触到镍催化剂的表面时，它们会被吸附到催化剂的活性位点上。

在活性位点上，一些分子键会被打破，使得水分子分解成氢气和氧气。

这种分解反应是一个高度放热的过程，会释放大量的能量。

分解出来的氢气会从镍催化剂的表面释放出来，成为一个可用的能源。

而释放出的氧气则会与周围的镍反应，形成一层氧化镍(NiO)的薄膜。

这层薄膜会阻止水分子再次接触到活性位点，从而停止反应的进行。

然而，氧化镍层并不稳定，在一定温度下就会被热还原成纯镍。

当氧化镍层被热还原时，活性位点再次暴露，可以重新催化水的分解反应。

这使得镍催化剂可以循环使用，成为一个持久的催化剂。

需要注意的是，水的分解反应不是一个自发性的反应，而是一个非常慢的反应。

催化剂的引入大大增加了反应速率，使得反应能够在合理的时间内进行。

这种催化作用在工业上被广泛应用，可以用于制取氢气以及其他相关的反应。

总结起来，氢和镍产生放热反应的原理是水的分解反应在镍催化剂的作用下进行。

镍催化剂通过其表面的活性位点吸附水分子，并使其分解成氢气和氧气，释放出大量的能量。

分解出来的氢气可以作为能源使用，而释放出的氧气则会形成氧化镍层，停止反应的进行。

随后，氧化镍层会被热还原成纯的镍，并重新催化水的分解反应。

这样，镍催化剂可以循环使用，实现高效的水分解反应。

镍表面上co和h2的吸附脱附速度

镍表面上co和h2的吸附脱附速度镍表面上CO和H2的吸附脱附速度
镍是一种普遍存在的金属，广泛用于精密装载及制造加工行业。

CO和H2是重要的过程中气体，它们在镍表面上的吸附脱附速度具有重要意义。

因此，研究镍表面上CO和H2的吸附脱附速度相关性也就显得十分必要。

研究表明，CO和H2在镍表面的吸附脱附速率以及气体的分子量都有关系，其中CO分子的大小对其吸附脱附速率的影响比H2分子大得多，温度、压力以及镍表面的活性也有一定的影响。

从实验可以发现，随着温度的提高，镍表面上CO与H2的吸附脱附速度都会比较明显地改变了，而且，温度越高，CO和H2在镍表面的脱附速度也越快。

此外，镍表面活性对CO和H2吸附脱附速度也会有一定的影响，研究发现，当镍表面活性提高时，CO和H2在其上的吸附脱附速度会减慢，反之亦然。

另外，镍表面上CO和H2的光照强度也会影响其吸附脱附速率，研究发现，随着光照强度的提高，CO和H2在镍表面的脱附速度也会随之增加，而吸附速度会相应地减慢。

因此，CO和H2在镍表面上的吸附脱附速度是由多种因素共同决定的，温度、压力、光照强度以及表面活性等参数都会影响其吸附脱附速率。

因此，在精密加工中应该综合考虑这些因素，以确保最优化处理效果。

溶解度计算有新招

溶解度计算有新招
肖光华
【期刊名称】《化学教学》
【年(卷),期】1994(000)004
【摘要】溶解度计算有新招湖南省洞县三中（４２２１３２）肖光华有关溶解度的计算、尤其是既有温度变化，又有溶剂变化，还有结晶水合物析出（或溶解）的计算，不仅初中学生，就是高中学生，一直是一根难啃的骨头，经常出现这样或那样的错误。

如何解决这一问题，笔者在高三复习中...
【总页数】2页(P37-38)
【作者】肖光华
【作者单位】湖南省洞县三中
【正文语种】中文
【中图分类】G633.8
【相关文献】
1.难溶电解质的计算溶解度小于实测溶解度的原因分析 [J], 孟凡盛
2.溶解度参数法计算超临界流体的溶解度 [J], 王伟彬;银建中;张礼鸣
3.金属镍吸附氢同位素的量子力学计算(二)--溶解度的计算方法 [J], 朱正和;孙颖;钟正坤;张莉;王和义
4.计算机在分析化学中的应用：Ⅰ 难溶化合物溶解度的计算 [J], 黄振钟;莫春生
5.338.15 K时四元体系CaCl_(2)-SrCl_(2)-BaCl_(2)-H_(2)O相平衡测定及溶解度计算 [J], 曹大群;金艳;陈杭;于建国
因版权原因，仅展示原文概要，查看原文内容请购买。

NO在稀有金属钇表面的吸附行为

NO在稀有金属钇表面的吸附行为
孙静波;姚建刚;彭智
【期刊名称】《原子与分子物理学报》
【年(卷),期】2024(41)5
【摘要】以往的理论在预测六方结构(HCP)金属的表面能时,计算值与实验值存在较大误差.鉴于此,本文首先用一种较为合理的方法精准地预测了稀有金属钇(Y)(0001)面的表面能,计算值(1.141 J/M^(2))与实验值(1.125 J/M^(2))吻合的很好.随后,系统研究了NO小分子在Y(0001)面不同位置(空位、桥位和端位)的吸附行为.结果表明:空位(H1)表现出了良好的吸附能力,吸附能超过了5eV,同时N-O键长伸长量超过了24%,此时,NO分子几乎平行地吸附于Y(0001)表面.所有的吸附位置的N-O分子伸长量范围为0.2-0.42.这种伸长量明显超过了NO在其它金属表面时的计算结果.
【总页数】6页(P33-38)
【作者】孙静波;姚建刚;彭智
【作者单位】烟台南山学院科技与数据学院;青岛大学材料科学与工程学院
【正文语种】中文
【中图分类】TG146
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1.银岛膜表面胸腺嘧啶吸附行为的表面增强拉曼光谱和表面增强红外光谱研究
2.金属钇表面吸附氢同位素的量子力学计算
3.表面活性剂和四烷基溴化铵的复配Ⅲ.四
烷基溴化铵碳氢链长对离子型表面活性剂在气/液表面吸附行为的影响4.钇在大孔膦酸树脂上的吸附行为及其机理5.表面活性剂和四烷基溴化铵的复配Ⅱ.四乙基溴化铵对离子型表面活性剂在气/液表面吸附行为的影响
因版权原因，仅展示原文概要，查看原文内容请购买。

合金在吸氢过程中,特征时间吸收90%储氢容量的时间

合金在吸氢过程中，特征时间吸收90%储氢容量的时间
合金在吸氢过程中，特征时间是指吸收90%储氢容量所需的时间。

这个时间通常用于评估合金的吸氢性能和速率。

合金的吸氢过程可以分为以下几个阶段：
1. 吸附阶段：在这个阶段，氢气分子被吸附到合金表面的活性位点上。

这个过程通常是快速的，并且与合金的表面积、表面活性位点的数量和类型有关。

2. 扩散阶段：在吸附阶段之后，氢气分子需要通过合金内部的孔隙或晶格扩散到合金内部。

这个过程通常较慢，并且与合金的孔隙结构、晶格缺陷等因素有关。

3. 储存阶段：在扩散阶段之后，氢气分子被储存在合金的内部。

这个过程通常是可逆的，并且与合金的储氢机制有关。

特征时间是衡量合金吸氢性能的重要指标之一。

它反映了合金在吸氢过程中的速率和效率。

一般来说，特征时间越短，合金的吸氢速率越快，储氢容量越大。

为了获得合金的特征时间，可以进行吸氢实验。

实验中，将一定量的合金样品置于含有氢气的气氛中，记录氢气压力随时间的变化。

当氢气压力达到90%储氢容量时，所经历的时间即为特征时间。

需要注意的是，不同的合金具有不同的特征时间，这取决于其组成、结构和储氢机制等因素。

因此，在选择合金材料进行吸氢应用时，需要考虑其特征时间是否符合实际需求。

化学技术操作中常见的溶解度计算方法

化学技术操作中常见的溶解度计算方法溶解度是指在一定温度和压力条件下，溶质在溶剂中溶解达到平衡时所能达到的最大溶解量。

在化学工程和研发中，溶解度的准确计算是非常重要的，因为它直接影响到反应的效率和产物的纯度。

本文将介绍常用的溶解度计算方法，以及它们的优缺点。

一、理论计算法理论计算法是通过分子间作用力理论或统计力学的方法推导出的溶解度计算方法。

其中最常见的理论计算法是拉乌尔（Raoult）定律和亨利（Henry）定律。

1. 拉乌尔定律拉乌尔定律适用于理想溶液，即溶质分子与溶剂分子之间无相互作用力。

根据拉乌尔定律，溶液的渗透压等于溶质摩尔分数乘以溶剂的蒸汽压。

溶液的溶解度可以通过拉乌尔定律计算出来。

拉乌尔定律的应用范围有限，因为它假设溶质与溶剂之间没有相互作用力，而实际溶液中经常存在着相互作用力。

2. 亨利定律亨利定律适用于气体溶解于液体中的情况。

根据亨利定律，气体在液体中的溶解度与气体的分压成正比。

溶液的溶解度可以通过亨利定律计算出来。

亨利定律也有其局限性，它假设在溶解过程中气体分子与溶液分子之间不存在相互作用。

二、实验测定法实验测定法是通过实际实验来确定溶液的溶解度。

常见的实验测定方法有浓度法、摄谱法和冷冻点法等。

1. 浓度法浓度法是根据溶液的浓度与溶质的数量之间的关系来计算溶解度。

首先制备一系列浓度不同的溶液，然后通过测定溶液的浓度，可以计算出溶质的溶解度。

浓度法的优点是简单易操作，但其结果受到测定精度的限制。

2. 摄谱法摄谱法利用溶质和溶剂在特定波长处的吸收特性来确定溶解度。

通过测量溶液在不同浓度下的吸光度，可以计算出溶质的溶解度。

摄谱法需要使用光谱仪等专业设备，且对样品的处理和测量条件要求较高。

3. 冷冻点法冷冻点法是利用溶液的冷冻点降低来计算溶解度。

根据溶液的冷冻点降低与溶质摩尔浓度之间的关系，可以计算出溶质的溶解度。

冷冻点法需要一定的仪器设备和实验条件，并且在高浓度下精度较低。

三、分子模拟法分子模拟法是利用计算机模拟分子的运动和相互作用来预测溶解度。

化学平衡中的溶解度计算方法

化学平衡中的溶解度计算方法在化学平衡中，溶解度是指溶液中固体物质达到平衡时所能溶解的最大量，通常用溶解度常数表示。

溶解度的计算是化学研究和实验中的重要内容，对于了解溶解物质在溶剂中的溶解程度和溶解平衡的性质非常关键。

本文将介绍一些常见的化学平衡中的溶解度计算方法。

一、溶解度计算方法1. 离子化合物的溶解度离子化合物溶于溶液中时，会发生电离产生正负离子。

离子化合物的溶解度可以通过溶解度积与离子浓度关系来计算。

溶解度积（Ksp）是指离子化合物在饱和溶液中离解产生正负离子的乘积，用于表示离解程度。

根据离子浓度的量度，可以使用浓度法或平衡常数法来计算溶解度。

- 浓度法：根据已知溶解度积的实验数据推导出浓度，进而计算溶解度。

- 平衡常数法：根据平衡常数表达式推导出溶解度。

2. 非离子化合物的溶解度非离子化合物在溶液中溶解时，不发生电离产生离子，因此其溶解度计算方法与离子化合物有所不同。

常见的非离子化合物包括分子化合物和共价化合物。

- 分子化合物的溶解度：通常使用溶解度规律来计算，如相似性规律、溶剂势能规律等。

- 共价化合物的溶解度：考虑了分子间力和极性等因素，可使用热力学方法、分子间作用力的数学模拟或实验测定等途径进行计算。

二、溶解度计算实例下面将通过两个实例来具体说明溶解度的计算方法。

1. 例一：氢氧化钠的溶解度计算氢氧化钠（NaOH）是一个离子化合物，其溶解度计算可以采用浓度法。

已知NaOH的溶解度积（Ksp）为1.0×10^-6 mol/L，现在我们需要计算其溶解度。

设NaOH溶解度为x mol/L，根据NaOH的离解方程可得Na+和OH-的浓度为x mol/L。

根据离子浓度与溶度积的关系：[Na+] × [OH-] = Ksp代入浓度，可得：x × x = 1.0×10^-6解得：x = 1.0×10^-3 mol/L因此，氢氧化钠的溶解度为1.0×10^-3 mol/L。

吸附容量的曲线n

Available online at Colloids and Surfaces A:Physicochem.Eng.Aspects320(2008)11–18Kinetics of adsorption of Saccharomyces cerevisiae mandelated dehydrogenase on magnetic Fe3O4–chitosan nanoparticlesGui-Yin Li a,b,Yu-Ren Jiang a,∗,Ke-Long Huang a,∗,Ping Ding a,Li-Li Yao aa College of Chemistry and Chemical Engineering,Central South University,Hunan410083,Chinab Hunan Vocational College of Science and Technology,Changsha,Hunan410118,ChinaReceived4August2007;received in revised form17December2007;accepted1January2008Available online19January2008AbstractThe adsorption of Saccharomyces cerevisiae mandelated dehydrogenase(SCMD)protein on the surface-modiﬁed magnetic nanoparticles coated with chitosan was studied in a batch adsorption system.Functionalization of surface-modiﬁed magnetic particles was performed by the covalent binding of chitosan onto the surface of magnetic Fe3O4nanoparticles.Characterization of these particles was carried out using FTIR spectra, transmission electron micrography(TEM),X-ray diffraction(XRD)and vibrating sample magnetometry(VSM).Magnetic measurement revealed that the magnetic Fe3O4–chitosan nanoparticles were superparamagnetic and the saturation magnetization was about37.3emu g−1.The adsorption capacities and rates of SCMD protein onto the magnetic Fe3O4–chitosan nanoparticles were evaluated.The adsorption capacity was inﬂuenced by pH,and it reached a maximum value around pH8.0.The adsorption capacity increased with the increase in temperature.The adsorption isothermal data could be well interpreted by the Freundlich isotherm model.The kinetic experimental data properly correlated with theﬁrst-order kinetic model,which indicated that the reaction is the adsorption control step.The apparent adsorption activation energy was27.62kJ mol−1and the ﬁrst-order constant for SCMD protein was0.01254min−1at293K.©2008Published by Elsevier B.V.Keywords:Adsorption kinetics;SCMD;Magnetic Fe3O4–chitosan nanoparticles1.1ntroductionAdsorption is a conventional but important separation pro-cess.It has been used widely in the chemical,analytical, environmental and biologicalﬁelds,especially in the separation of proteins.In most cases,the adsorbents have diameters in the range of submicron to micron and have large internal porosities to ensure adequate surface area for adsorption[1].However, the diffusion limitation within the particles leads to decreases in the adsorption rate and available capacity.Therefore,it is important and interesting to develop a novel adsorbent with a large surface area for adsorption,a small diffusion resistance and a high capacity for large solutes.Nanotechnology has been quickly developed in variousﬁelds in the past pared to the traditional micron-sized supports used in separation pro-∗Corresponding authors.Tel.:+867318836834;fax:+867318859988.E-mail addresses:jiangyr@(Y.-R.Jiang),klhuang@(K.-L.Huang).cess,nano-sized carriers possess quite good performance due to high speciﬁc surface area and the absence of internal diffusion resistance[2].Magnetic particles ranging from nanometer to micrometer scale are being used in an increasing number of bioapplica-tions[3]such as the immobilization of proteins,peptides and enzymes[4,5],bioafﬁnity adsorbents[6],drug delivery[7,8], biosensor[9]and so on.Particles in the nanosize range possess distinctively different physiochemical,magnetic,and optical properties compared to their bulk phase.The ideal magnetic nanoparticles for bioapplications would have these desirable properties,i.e.,uniform size,high surface area,fast adsorption kinetics,biocompatibility,as well as superparamagnetism with high magnetic strength[10,12].Thus,there are many reports on using nanosize magnetic bodies to adsorb proteins[11,12], enzymes which include lipase,ribonuclease,lysozyme,peni-cillin G acylase,glucose oxidase and so on[13–16].Often,an additional inorganic or polymeric coating layer is necessary to avoid magnetically induced self-aggregation of magnetic cores and to improve the functionality or biocompatibility of these0927-7757/$–see front matter©2008Published by Elsevier B.V. doi:10.1016/j.colsurfa.2008.01.01712G.-Y.Li et al./Colloids and Surfaces A:Physicochem.Eng.Aspects320(2008)11–18nanostructures.Shamim et al.[17,18]prepared an organic–inorganic nanoadsorbent with a mean diameter of12nm using surface modiﬁed Fe3O4as the core and N-isopropylacrylamide as the polymer shell.These thermosensitive nanoparticles were used as a bioseparation tool for the separation of BSA.The adsorption and desorption was done quickly due to high adsorp-tion capacity.Bucak et al.[19]synthesized phospholipid-coated colloidal magnetic nanoparticles with mean magnetite core size of8nm for the adsorptive separation of model hydrophilic pro-teins.These particles were of high adsorptive capacities(up to1200mg protein/ml adsorbent),and used as effective ion exchange media for the recovery and separation of proteins from protein mixtures and exhibited none of the diffusion resistances offered by conventional porous ion exchange media.Alcohol dehydrogenase which catalyzes the oxidation of alcohols and the reduction of carbonyl compounds such as alde-hydes and ketones has attracted attention because of its potential applications in the production of various starting materials and intermediates in chemical industry.It is well known that Saccha-romyces cerevisiae possesses several alcohol dehydrogenases and shows good capacity as a redox biocatalyst in a variety of stereoselective reductions and in the regeneration of coenzymes NAD(P)H in vivo continuously[20].S.cerevisiae mandelated dehydrogenase(SCMD),a kind of alcohol dehydrogenases,can catalyze the reduction of phenylglyoxylic acid to(R)-mandelic acid[21],which is widely used as a precursor for the manufac-ture of semi-synthetic penicillin and cephalosporin and also for the synthesis of various other pharmaceuticals[22].The characteristic of protein adsorption on surfaces of mag-netic particles is of particular importance as it reﬂects the interaction between synthetic materials and the biomolecule of interest.Besides mimicking some of the in vivo processes like drug delivery,the adsorption of protein is also a key reaction step in many bioprocesses found in the food and pharmaceutical industries[11].The goal of this paper is to report on the syn-thesis of single-domain magnetic nanoparticles with chitosan coatings and on their use in the adsorptive immobilization of the SCMD.The equilibrium of adsorption SCMD onto the magnetic Fe3O4–chitosan nanoparticles was investigated in detail and the kinetic of adsorption was also suggested.2.Materials and methods2.1.MaterialsStrains(S.cerevisiae,strain No.3)used in this work were obtained from our culture collection and alcohol dehydroge-nase(EC1.1.1.1)from S.cerevisiae was prepared as described in Section 2.5.Phenylglyoxylic acid was purchased from Sigma Chemical Company.Nicotinamide adenine dinucleotide, reduced form(NADH)was procured from Roche Ltd.Chitosan (CTS,MW4.9×105,degree of deacetylation95%)was pro-cured from Dalian Xindie Chitin Company(Dalian,China). 25%Glutaraldehyde solution was purchased from Hunan Nor-mal University Chemical Company(Hunan,China).Ferrous sulphates heptahydrate and aqueous ammonia solution were purchased from Tianjin No.3Chemical Plant(Tianjin,China).Other chemicals were the analytic grade reagents commercially available and used without further puriﬁcation.All solutions were prepared with distilled,and deionized water.2.2.Synthesis of Fe3O4magnetic nanoparticles by hydrothermal methodFe3O4nanoparticles were prepared by hydrothermal method with a ferrous complex using H2O2as an oxidizer.Ferrous sul-phates heptahydrate(2.50g)were dissolved in30ml water,then 10ml50g L−1PEG-20000and30ml NH4OH solution were added to the solution at30◦C under vigorous stirring.During the reaction process,the pH was maintained at about10.After-wards,0.27ml of30%H2O2solution was added to the stirred mixture for20min.The mixture was put into the autoclaves and heated at160◦C for5h in a furnace.The Fe3O4nanopar-ticles were gained by centrifugation at8025×g for15min and washed several times with water and ethanol,andﬁnally dried in a vacuum oven at70◦C.2.3.Preparation of magnetic Fe3O4nanoparticles coated with chitosanFe3O4nanoparticles(0.2g)were washed with99.5%ethanol twice and dispersed in a solution with30ml parafﬁn and0.5ml span-80,then15.0ml of chitosan(0.2g)dissolved in acetic acid with concentration of5%were added.The suspension was mixed by ultrasonic irradiation for30min.The suspension was then transferred into a three-neckedﬂask with a mechanical stir-rer after adding3ml25%glutaraldehyde solution.After4h,the Fe3O4–chitosan nanocomposite particles were recovered from the reaction mixture by placing the bottle on a permanent magnet with a surface magnetization of6000G.The magnetic particles settled within1–2min.The supernatant was removed and the precipitant were washed several times with water and ethanol and dried at50◦C in a vacuum oven.2.4.Particles characterizationThe average particle size and morphology of the samples were observed by TEM using a H-600transmission electron microscope.XRD measurement was performed on a Philips D/Max-2500diffractometer,using a monochromatized X-ray beam with nickel-ﬁltered Cu K␣radiation with4◦min−1scan rate.A continuous scan mode was used to collect2θdata from 10◦to90◦.The magnetization curves of the dried microspheres were recorded with a JDM-13D magnetometer.The hysteresis of the magnetization was obtained by changing H between+4000 and−4000Oe at25◦C.FTIR spectra of CTS,Fe3O4nanoparti-cles and Fe3O4–chitosan nanoparticles were recorded with KBr discs in the range of4000–400cm−1on Nicolet A V ATAR360 Fourier-transfer infrared.2.5.Production and puriﬁcation of SCMDS.cerevisiae was cultivated in Rough bottles in the follow-ing culture medium(g/L):glucose50,peptone3.0,yeast extractG.-Y.Li et al./Colloids and Surfaces A:Physicochem.Eng.Aspects320(2008)11–18132.5,K2HPO41.0,MgSO4·7H2O0.5,NaCl0.5,Fe2(SO4)30.01,ZnSO40.01,pH6.5.The cells were incubated at30◦C and har-vested after24h.Then the cells were collected from culture bycentrifugation at6687.5×g at4◦C for15min.Cell pellets weresuspended with10ml0.9%sterile physiological saline per gramof cell pellet and disrupted by using Ultrasonic vibra cell crusherKS-250F(power400W,120times,work8s,stop8s).The dis-rupted cell mixture was centrifuged at6687.5×g for10minat4◦C and the supernatant was collected and precipitated withammonium sulphate atﬁnal concentration of3M.The precipi-tant was collected by centrifugation at6687.5×g for15min at4◦C and then resuspended in5ml of phosphate buffer(0.2M,pH6.8)per100mg of precipitant.The resuspended solution wasdialyzed overnight against500ml of phosphate buffer(0.2M,pH6.2).The dialyzed sample was clariﬁed by centrifugation at12,000×g for20min and the crude SCMD protein solution wasobtained in the supernatant.2.6.Protein adsorption on magnetic Fe3O4–chitosannanoparticlesMagnetic Fe3O4–chitosan nanoparticles(50mg)were redis-persed in30ml of5%glutaraldehyde phosphate buffer solutionat pH6.8and kept at room temperature for10h.The nanoparti-cles were separated by magnetic decantation placing the bottleon a permanent magnet with a surface magnetization of6000G,and washed several times with deionized water.Then differ-ent concentrations of SCMD solution(30ml0.2mM phosphatebinding buffer,pH8.0)were added to the particles.The resultingsuspensions were subsequently incubated at room temperaturewith shaking for3h,which proved to be a sufﬁcient period toreach equilibrium.At the end of incubation,the immobilizedSCMD were separated by magnetic decantation,washed with aphosphate buffer solution at pH7.0(5×2ml),and were used tomeasure the activity of the immobilized SCMD.The supernatantSCMD concentration was determined by Lab Tech UV2100spectrophotometer(absorption at280nm)with bovine serumalbumin as the standard.The protein adsorption capacity wascalculated by mass balance.The adsorbed amount of SCMD perunit weight of magnetic Fe3O4–chitosan nanoparticles at time t,Q(t)(mg g−l)was calculated from the mass balance equation asQ(t)=(C0−C t)Vm(1)where C0and C t(mg ml−1)are the initial SCMD concentration and the SCMD concentrations at any time t,respectively;V is the volume of the SCMD solution;and m is the weight of the magnetic Fe3O4–chitosan nanoparticles.2.7.Activity measurementThe activity of SCMD immobilization onto the magnetic Fe3O4–chitosan nanoparticles was determined according the references[23,24]with some modiﬁcations.The activity of immobilized SCMD was determined by measuring the initial reduction rate of phenylglyoxylic acid by SCMD at the desired temperature following the decrease in absorbance of NADH at 340nm on a Lab Tech UV2100spectrophotometer.Generally, 4ml phosphate buffer solution(0.02M,pH7.0),1ml1mM NADH solution and1ml0.1M phenylglyoxylic acid solution were mixed to the test tube,then10mg SCMD-immobilized magnetic nanoparticles(1ml0.14mg/ml SCMD solution immo-bilized on the10mg magnetic nanoparticles)was added.After mixing for several minutes by vortex,the liquid solution sepa-rated from the magnetic nanoparticles via a permanent magnet was used for the analysis of NADH concentration.To compare the activity of SCMD with and without immo-bilized the magnetic Fe3O4–chitosan nanoparticles,the initial reduction rate of phenylglyoxylic acid by free SCMD follow-ing the decrease of NADH concentration was measured at the same condition as that of SCMD immobilized on the magnetic Fe3O4–chitosan nanoparticles.One unit of SCMD activity(U)was deﬁned as the amount of SCMD which used up1nm NADH per minute at25◦C and pH 7.0.3.Results and discussion3.1.Characterization of the magnetic nanoparticlesFig.1showed the FTIR spectra of the naked Fe3O4(a), CTS(b)and Fe3O4–chitosan nanoparticles(c).The peak around 3440cm−1observed in curve b and c relates to the–OH group. For the naked Fe3O4(Fig.1(a)),the peak at569cm−1relates to Fe–O group.For the IR spectrum of CTS(Fig.1(b)),the charac-teristic absorption bands appeared at1589cm−1which can be assigned to N–H bending vibration,peaks1399cm−1appeared to–C–O stretching of primary alcoholic group in chitosan.In the spectrum of Fe3O4–chitosan nanoparticles(Fig.1(c)),compared with the spectrum of CTS,the1589cm−1peak of N–H bending vibration shifted to1562cm−1,and a new sharp peak1627cm−1 appeared,it indicated that chitosan react with glutaraldehyde to form Schiff base,and a new sharp peak560cm−1relates toFe–O Fig.1.FTIR spectra of the naked Fe3O4(a),CTS(b)and Fe3O4–chitosan nanoparticles(c).14G.-Y.Li et al./Colloids and Surfaces A:Physicochem.Eng.Aspects 320(2008)11–18Fig.2.TEM micrographs for magnetic nanoparticles without (a)and with (b)chitosan,the bar is 100nm.group appeared.The results indicated that CTS was coated to the magnetic Fe 3O 4nanoparticles successfully.Because the sur-face of iron oxide with negative charges has an afﬁnity toward CTS,protonated CTS could coat the magnetite nanoparticles by the electrostatic interaction and chemical reaction through glutaraldehyde cross-linking.The typical TEM micrographs for magnetic nanoparticles with and without chitosan coating were shown in Fig.2.From Fig.2(a),it was clear that the naked Fe 3O 4nanoparticles were essentially monodisperse and had a mean diameter of 20nm.After coating with chitosan (Fig.2(b))the particles remained dis-crete with a mean diameter of about 25nm.This revealed that the coating process did not signiﬁcantly result in the agglomeration and the change in size of the particles.This could be attributed to the reaction occurring only on the particle surface.But there is little aggregative phenomenon in the Fe 3O 4nanoparticles coated with chitosan.Fig.3showed the XRD patterns for the naked and Fe 3O 4nanoparticles coated with chitosan.It indicated that Fe 3O 4isFig.3.XRD patterns for magnetic nanoparticles without (a)and with (b)chi-tosan.the dominant phase in both the samples,but the entire peak is broadened.Six characteristic peaks for Fe 3O 4marked by their indices ((220),(311),(400),(422),(511)and (440))were observed for both samples.These peaks are consistent with the database in JCPDS ﬁle (PDF No.65-3107)and reveal that the resultant nanoparticles were pure Fe 3O 4with a spinel structure.It is also explained that the coating process did not result in the phase change of Fe 3O 4.Fig.4showed the magnetization curves of (a)magnetic Fe 3O 4particles (b)magnetic Fe 3O 4–chitosan nanoparticles obtained by VSM at 25◦C.The saturation magnetization (σs )of the chitosan-magnetite nanocomposites was about 37.3emu g −1,while for the pure magnetite nanoparticles the σs was 83.2emu g −1.As could be seen in Fig.4,no remainance and coercivity is observed,which indicated that the magnetic nanoparticles are superparamagnetic.Superparamagnetism (i.e.responsiveness to an applied magnetic ﬁeld withoutretainingFig.4.Magnetization curves of (a)magnetic Fe 3O 4particles and (b)magnetic Fe 3O 4–chitosan nanoparticles obtained by VSM at 25◦C.G.-Y.Li et al./Colloids and Surfaces A:Physicochem.Eng.Aspects320(2008)11–1815Fig.5.Adsorption kinetic of SCMD protein on the magnetic Fe3O4–chitosan nanoparticles with different pH(temperature25◦C).any magnetism after removal of the magneticﬁeld.)is an espe-cially important property needed for magnetic targeting carriers. These results also indicated that the single domain magnetic nanoparticles remained in these polymer nanoparticles.The decrease of the saturation magnetization is most likely attributed to the existence of span-80on the surface of Fe3O4nanoparti-cles which may create a magnetically dead layer.In addition,the magnetic molecules on the surface lack complete coordination and thus increase the surface spin disorientation.This disordered structure in the amorphous materials and at the interface might have caused a decrease in the effective magnetic moment[17].3.2.Effect of pH on SCMD protein adsorptionFig.5showed the effect of pH on the adsorption of SCMD onto the magnetic Fe3O4–chitosan nanoparticles.The adsorp-tion capacity increases with increasing pH of the solution(pH 5.8–8.0).The maximum adsorption capacity of SCMD on mag-netic Fe3O4–chitosan nanoparticles is found at pH8.0.This could be explained by the fact that at low pH,more protons will be available to protonate amine groups to form groups NH3+,reducing the number of binding sites for the adsorption of SCMD.The adsorption behavior showed that adsorption of protein onto magnetic nanoparticles is governed by hydropho-bic interaction and by electrostatic interactions[18,25].The inﬂuence of pH on the adsorption capacity showed decreasing afﬁnity with increasing electrostatic repulsion between protein and adsorbent and a maximum plateau value at pH8.0.3.3.Adsorption isotherm of SCMD proteinFig.6displayed the equilibrium adsorption data con-cerning the adsorption of SCMD protein on the magnetic Fe3O4–chitosan nanoparticles at4,20,30and45◦C,respec-tively.There was a gradual increase of adsorption for SCMD protein until equilibrium was attained.The adsorption capacities at different temperatures are very different.Adsorption isotherm is important to describe how solutes interact with adsorbent.The Fig.6.Adsorption isotherms of SCMD protein on the magnetic Fe3O4–chitosan nanoparticles at4,20,30and45◦C,respectively.Langmuir and Freundlich models are frequently employed to describe the adsorption process.The Langmuir adsorption model is given asQ=K L Q m C1+K L C(2)where Q is the amount of SCMD protein adsorbed per unit weight of the magnetic Fe3O4–chitosan nanoparticles at equilib-rium concentration(mg g−1),C is the equilibrium concentration in the solution(mg ml−1),Q m is the maximum adsorption at monolayer coverage(mg g−1),and K L is the Langmuir constant related to the afﬁnity of binding sites(ml mg−1).Eq.(2)can also be expressed as follows:CQ=CQ m+1Q m K L(3) Freundlich adsorption isotherm model,which is an empirical equation used to describe heterogeneous adsorption systems, can be represented as follows:Q=K F C1/n(4)where Q and C are deﬁned as above,K F is Freundlich con-stant representing the adsorption capacity(mg g−1),and n is the heterogeneity factor depicting the adsorption intensity.In most reference,Freundlich adsorption Eq.(4)may also expressed as Eq.(5)log Q=log K F+1n log C(5) Weﬁt the adsorption isotherms in Fig.6to Langmuir and Freundlich adsorption equations.The regression equations, parameters K L,K F and n,as well as the correlation coefﬁ-cients R are summarized in Table1.It is shown that Freundlich isotherm is suitable for characterizing the experimental adsorp-tion isotherms since all of the correlation coefﬁcients are larger than0.99.As known to us all,Langmuir isotherm is on the supposition that the surface of the adsorbent is a homogeneous16G.-Y.Li et al./Colloids and Surfaces A:Physicochem.Eng.Aspects 320(2008)11–18Table 1The regression results for adsorption of SCMD protein on the magnetic Fe 3O 4–chitosan nanoparticles Temperature (◦C)The regression equation K L Q m R Langmuir isotherm equation 4C /Q =0.00855+0.00715C 139.8600.8360.94920C /Q =0.00416+0.00846C 118.203 2.0340.98930C /Q =0.00417+0.00713C 140.252 1.7090.99145C /Q =0.00398+0.00655C 152.671 1.6540.988Temperature (◦C)The regression equation K F n R Freundlich isotherm equation 4log Q =1.82972+0.75842log C 67.656 1.3190.99720log Q =1.94116+0.60433log C 87.329 1.6550.99630log Q =1.99194+0.64765log C 98.161 1.5440.99845log Q =2.02201+0.65600log C105.1971.5240.998surface,whereas Freundlich isotherm is applied to the adsorp-tion process on a heterogeneous ngmuir adsorption model is classically used for protein adsorption at an interface,surface,or membranes [26,27].The Langmuir model assumes that the adsorption can take place only at speciﬁc localized sites on the surface and that the saturation coverage corresponds to complete occupancy of these sites.At 20,and 30◦C,the experi-mental adsorption isotherm data can ﬁt the Langmuir adsorption model well.3.4.Kinetics of adsorptionThe adsorption kinetic experiments were carried out to eval-uate the rate and the activation energy of the SCMD protein adsorption process on the magnetic Fe 3O 4–chitosan nanoparti-cles.The kinetics of the adsorption process was followed by determining the amounts of adsorbed SCMD protein at var-ious time intervals in the following temperatures:4,20,30and 45◦C,as shown in Fig.7.The results indicated thattheFig.7.Adsorption kinetic of SCMD on the magnetic Fe 3O 4–chitosan nanopar-ticles with different temperature (initial protein concentrations:0.14mg/ml,pH 8.0).amount of SCMD adsorbed was not affected signiﬁcantly over the examined temperature range.The time necessary to reach equilibrium for the different studied temperatures is practically about 180min and signiﬁcant increases in the adsorbed amounts are not observed after the equilibrium stage.It is also a well-recognized fact that the process of adsorp-tion is a two-regime process [28].At the initial stage,the solid surface is bare,and the kinetics of adsorption is governed by the diffusion of the molecules from the bulk solution to the surface.All of the molecules that arrive at the surfaces are assumed to be immediately adsorbed.The mass transport can be interpreted as a Fickian diffusion equation:Q t =k i t 0.5(6)where k i is the diffusion rate (mg g −1min −0.5).The experimen-tal data (shown in Fig.7)were plotted as Q t versus t 0.5and the results were shown in Fig.8.From the slope of the curve Q t as a function of t 0.5,the diffusion constant k i can becalculated.Fig.8.Plot of the Fickian diffusion equation at different temperatures.G.-Y.Li et al./Colloids and Surfaces A:Physicochem.Eng.Aspects 320(2008)11–1817Table 2Adsorption kinetic parameters at different temperature Fickian diffusion model Pseudo ﬁrst-order model Temperature (◦C)k i (mg g −1min −0.5)R k 1(min −1)Q e ,cal R4 1.06540.98150.0141614.69740.9948200.81390.99310.0125410.39740.9976300.83510.94490.0208412.52030.9927450.49320.90530.030169.65950.9878In the later stage,a barrier of adsorbed molecules exists,and the molecules arriving from solution have to diffuse across this barrier.This penetration is slow,and the speciﬁc rate constants of the SCMD protein adsorption can be determined from the pseudo ﬁrst-order kinetic model—Lagergren Equation ln(Q e −Q t )=ln Q e −k 1t(7)where Q e and Q t are the amounts of SCMD protein adsorbed on adsorbent (mg g −1)at equilibrium and at time t ,respectively,and k 1is the rate constant of ﬁrst-order adsorption (min −1).Straight-line plots of log(Q e −Q t )against t were used to determine the rate constant,k 1and correlation coefﬁcient.With the help of Figs.8and 9,drawn in accordance with Eqs.(6)and (7),respectively,the diffusion constant k i and the ﬁrst-order rate constants k 1have been calculated.These were summarized in Table 2.Based on the correlation coefﬁcients,the adsorptions of SCMD protein were best described by the ﬁrst-order equation,similarly to other report of the protein adsorption on solid phases [28,29].The ﬁrst-order kinetic process has been used for reversible reaction with an equilibrium being estab-lished between liquid and solid phases.Generally,a rise in temperature of a chemical reaction increases the rate of the reaction,and the temperature depen-dence results in a change in the rate constant.Activation energy of the sorption can be estimated by Arrhenius equation provid-ing the relationship between the rate constant andtemperatureFig.9.Plot of the pseudo ﬁrst-order equation at different temperatures.as shown in the following equation:ln k =ln A −E a RT(8)where k is the rate constant of adsorption,A the Arrhenius con-stant which is a temperature independent factor,E a the activation energy,R the gas Constant and T is the solution temperature in Kelvin.In this work,activation energy of sorption process has been calculated using the values of rate constant from a ﬁrst-order kinetic equation and using the appropriate solution temperatures.The plots of ln k versus 1/T were found to be lin-ear in the temperatures range of 20–45◦C.The value of E a from the slope of the plot was 27.62kJ mol −1.The relatively low acti-vation energy indicates the adsorption of SCMD is easily taken place by the magnetic Fe 3O 4–chitosan nanoparticles.3.5.Activity of immobilized SCMDThe effect of adsorption on the activity of SCMD was exam-ined to demonstrate the practicability for biocatalysing the reduction of phenylglyoxylic acid to (R )-mandelic acid.Fol-lowing the determination activity of SCMD with and without immobilized Fe 3O 4–chitosan method,we measured the activity of free SCMD and immobilized SCMD at 25◦C and pH 7.0.For free SCAD,the activity is 360.655U,while for the immobilized SCMD,the activity is 176.014U,48.8%activity was retained.The duration of a catalyst is an important feature for its potential application in industry.To investigate the reusability of immobilized SCAD,several repetitive use of immobilized SCAD were operated.After each cycle,the immobilized SCAD was recovered by magnetic separation and recycled for the reduction of phenylglyoxylic acid.The activity of the ﬁrst batch was taken as 100%.The assay condition remained the same for all batches.Within seven cycles of usage,the remaining activity was about 100%,89.15%,79.42%,69.50%,62.80%,56.48%,and 48.26%of the ﬁrst use.The activity of the immobilized SCAD in the repeated use did not decrease signiﬁcantly.Although the immobilized SCMD activity decreased signiﬁ-cantly,the immobilized SCMD had a good durability and could be readily recovered by magnetic separation.This revealed the magnetic Fe 3O 4–chitosan nanoparticles indeed could be practi-cally used for the immobilized of enzymes.4.ConclusionsMagnetic Fe 3O 4–chitosan nanoparticles were fabricated by the covalent binding of chitosan onto the surface of the mag-。

初中化学计算方法总结

初中化学计算方法总结1. 化学计算的基本概念化学计算是化学中非常重要的一部分，它涉及到化学方程式的平衡、摩尔计算、溶液浓度计算等内容，为学习和掌握化学知识提供了基础。

在初中阶段，我们需要掌握一些常见的化学计算方法。

2. 化学方程式的平衡计算化学方程式的平衡是化学反应中非常关键的一环，平衡的化学方程式可以通过化学计算方法得到。

一般来说，平衡的化学方程式应该满足质量守恒和电荷守恒两个原则。

通过平衡方程中物质的摩尔系数，可以得到化学方程式的平衡计算式。

例如，下面是氢气与氧气生成水的化学方程式：2H₂ + O₂ → 2H₂O经过平衡计算，可以得到氢气和氧气的摩尔系数分别为2和1，从而满足质量守恒和电荷守恒的原则。

3. 摩尔计算摩尔是化学中的重要概念，摩尔质量指的是物质的相对分子质量或原子量，单位是g/mol。

摩尔计算是通过已知物质的质量或物质的数量，计算其他物质的质量或物质的数量。

例如，如果已知硫酸钠(Na₂SO₄)的摩尔质量为142 g/mol，我们可以通过知道的质量计算出物质的摩尔数，公式如下：摩尔数 = 质量(g) / 摩尔质量(g/mol)4. 溶液浓度计算溶液浓度是描述溶液中溶质与溶剂的相对含量的参数，常用的浓度单位有摩尔浓度、质量浓度和体积浓度等。

在化学计算中，我们常常需要计算溶液的浓度。

例如，已知某个溶液中NaCl的质量为10 g，溶液的体积为100 mL，我们可以通过下面的公式计算出溶液的质量浓度：质量浓度(g/mL) = 质量(g) / 体积(mL)5. 其他常用的化学计算方法除了上述的基本计算方法外，还有一些常用的化学计算方法需要了解：•摩尔比计算：通过已知物质的摩尔数，计算其他物质的摩尔数的比例•溶质的溶解度计算：通过溶质的溶解度常数，计算溶液中溶质的量•配平氧化还原反应方程式：通过电子转移数目和电荷守恒原则，完成反应方程式的配平6. 总结初中化学计算方法是化学学习中非常重要的一部分，通过掌握这些基本的计算方法，可以更好地理解和应用化学知识。

氢在金属镍台阶表面上吸附的理论研究

氢在金属镍台阶表面上吸附的理论研究近年来，氢在金属表面上的吸附机理受到学界的广泛关注。

氢是一种轻质助剂，在许多金属的表面上能够形成均匀的、强紧凑的受控薄膜，从而影响材料的电子结构，物理和化学性质。

此外，在金属表面上形成的氢膜还可以有效地阻止金属表面受到氧化和污染，从而改善材料的力学和/或化学性能。

金属镍是一种重要的工程材料，具有抗腐蚀，耐高温和低温性能优越的金属材料，广泛应用于汽车、航空、工业、公共设施等行业。

因此，研究金属镍表面上氢的吸附机理及其影响其导电性、耐腐蚀性和力学特性的因素对于改善金属镍材料的性能非常重要。

首先，本文将研究金属镍表面上氢的吸附机理。

金属镍表面的氢吸附可以使金属的电子构型发生变化，影响金属材料的导电性能。

由于氢原子小，它们与金属原子之间的作用力较弱，形成的受控薄膜体系中更易于存在空位。

在氢原子吸附过程中，氢原子可以与金属镍表面上的金属原子结合，形成氢原子缺失的排列结构。

其次，本文将研究受氢态影响的金属镍表面腐蚀行为和耐腐蚀性问题。

氢在金属表面上的吸附可以延长材料的寿命，因为在金属表面形成的氢膜可以有效地抑制金属的氧化和腐蚀，从而改善材料的耐腐蚀性。

通过研究受氢态影响的金属表面的腐蚀行为，可以更好地探索氢在金属表面上的吸附及其影响材料性能的机理，有助于优化金属材料的结构设计，减少金属表面的腐蚀，提高材料的耐腐蚀性能。

最后，本文将研究金属镍表面氢原子的吸附对其力学性能的影响。

氢在金属表面上的吸附剂可以改变金属材料的电子和结构，使金属材料更有利于形成紧凑的晶格。

氢的吸附可以缩短金属的力学性能，改善金属的抗拉强度和抗压强度，因此氢原子的吸附可以改善材料的力学性能。

综上所述，研究金属镍表面上氢的吸附机理和其影响材料性能的因素具有重要意义，不仅可以改善材料的电子结构，而且可以改善材料的耐腐蚀性和力学性能。

研究的结果为金属镍材料的表面处理提供了重要的理论指导，对于开发出更具耐腐蚀性和力学性能的高性能金属镍材料具有重要的实际意义。

镀镍槽中阳极镍块溶解的计算方法

镀镍槽中阳极镍块溶解的计算方法
现代电镀网讯：
在电镀镍的过程中，阳极镍块的溶解全部用于补充平衡被还原为金属镍的量。

由W=V×ρ
式中：W ---- 质量(g)
V ---- 体积(cm3)
ρ---- 密度(g/cm3)
则有：
W镍=V镍×ρ镍
式中：W镍---- 镍块溶解质量(g)
V镍---- 镀镍层的体积(cm3)
ρ镍---- 金属镍的密度(g/cm3)
因：V镍=S镍×H镍，代入上式，可得：
W镍=S镍×H镍×ρ镍
式中：W镍---- 镍块溶解质量(g)
S镍---- 镀镍面积(cm2)
H镍---- 镀镍厚度(cm)
ρ镍---- 金属镍的密度(8.902g/cm3)
【单位换算：1平方英尺(FT2)=929.0304平方厘米(cm2)； 1微英寸(uinch)=2.54厘米(cm)】
依上述式，可知镍块溶解质量的算法为：
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镀镍槽中阳极镍块溶解的计算方法
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以上公式仅做理论性参考，实际生产过程中，还涉及带出消耗和其他一些不可预知因素的影响，可能实际的溶解量与计算结果有出入。

氢气在镍钯溶解度-概述说明以及解释

氢气在镍钯溶解度-概述说明以及解释1.引言1.1 概述概述部分的内容应该涵盖对于氢气在镍钯溶解度的简要介绍以及研究背景。

可以按照以下方式进行撰写：概述氢气在镍和钯金属中的溶解度是氢材料学领域中一个重要的研究领域。

镍和钯是两个常用的催化剂和吸氢材料，对于氢能源存储、氢化反应和氢传递等领域具有广泛的应用。

了解氢气在镍和钯中的溶解度对于揭示氢在金属中的吸附、扩散和吸附行为，以及材料的氢化性能具有重要意义。

随着氢能源技术的发展和应用领域的拓展，对于氢气在金属中的溶解度进行深入研究成为研究的热点之一。

目前的研究表明，氢气在镍和钯中的溶解度受到多种因素的影响，如温度、压力、合金成分等。

其中，镍钯合金作为一种重要的氢吸附材料，其表面形貌、晶体结构和杂质掺杂等因素也会对氢气的吸附和扩散行为产生显著影响。

本文将重点探讨氢气在镍和钯金属中的溶解度，通过综合分析已有的研究成果，总结氢气在镍和钯中的溶解度规律，并展望未来研究的方向和发展趋势。

通过对氢在镍、钯金属中的溶解度的深入研究，有望为氢能源技术的进一步发展和应用提供有力的理论和实验支持。

同时，本文还将探讨氢气在镍钯合金中的溶解度与材料性能之间的关联，为材料设计和合金优化提供一定的参考和借鉴。

文章结构部分应该介绍文章的整体结构和内容安排，以便读者能够更好地理解文章的组织和主要内容。

在这个部分，可以简要描述每个章节的主题和目标，以及它们在整体文章中的位置和作用。

可以按照以下方式写作文章结构部分：1.2 文章结构本文按照如下结构展开，以便系统地探讨氢气在镍和钯中的溶解度。

第一部分是引言。

在引言中，我们将概述本文的研究背景和意义，并阐述本文的目的和重要性。

第二部分是正文。

正文分为两个章节，分别讨论氢气在镍和钯中的溶解度。

2.1 氢气在镍中的溶解度。

这一章节将详细介绍氢气在镍中的物理和化学特性，以及氢气在镍中的溶解行为和影响因素。

我们将探讨镍与氢气的相互作用机制，并讨论涉及到氢气溶解度的实验方法和测定结果。

化学中金属的相关计算公式

化学中金属的相关计算公式金属的相关计算公式。

金属是化学中非常重要的一类物质，它们具有良好的导电性、导热性和延展性，因此在工业生产和科学研究中有着广泛的应用。

在化学中，我们经常需要进行金属的相关计算，比如计算金属的密度、摩尔质量、电子结构等。

本文将介绍一些常见的金属相关计算公式，并且通过实例进行说明。

1. 金属的密度计算公式。

金属的密度是指单位体积内金属的质量，通常用公式ρ = m/V 来表示，其中ρ表示密度，m表示质量，V表示体积。

在实际计算中，我们通常会用到金属的摩尔质量和晶胞体积来计算密度。

金属的摩尔质量可以通过化学式和元素的相对原子质量来计算，晶胞体积可以通过晶格常数来计算。

下面我们通过一个实例来说明金属密度的计算方法。

例如，我们要计算铁的密度。

铁的化学式为Fe，相对原子质量为55.85g/mol，晶格常数为0.286nm。

首先我们可以计算出铁的摩尔质量：M(Fe) = 55.85g/mol。

然后我们可以计算出铁的晶胞体积：V = a^3 = (0.286nm)^3 = 0.0234nm^3。

最后我们可以通过摩尔质量和晶胞体积来计算铁的密度：ρ = m/V = 55.85g/mol / 0.0234nm^3 = 2.38g/cm^3。

因此，铁的密度为2.38g/cm^3。

2. 金属的摩尔质量计算公式。

金属的摩尔质量是指1mol金属的质量，通常用公式M = nM来表示，其中M 表示摩尔质量，n表示摩尔数，M表示相对原子质量。

金属的摩尔质量可以通过化学式和元素的相对原子质量来计算。

下面我们通过一个实例来说明金属摩尔质量的计算方法。

例如，我们要计算铜的摩尔质量。

铜的化学式为Cu，相对原子质量为63.55g/mol。

我们可以直接通过元素的相对原子质量来计算铜的摩尔质量：M(Cu) = 63.55g/mol。

因此，铜的摩尔质量为63.55g/mol。

3. 金属的电子结构计算公式。

金属的电子结构是指金属中电子的排布情况，通常用壳层结构来表示。

化学计算公式总结

面连小草也长不出来的。

化学计算公式一、计算相对原子质量某原子的质量（kg）原子的相对原子质量＝——————————————如：碳原子质量(kg)×1∕12氢原子的质量（Kg） 1.674×10-27 KgAr（H）= —————————— = ———————————≈ 1 碳12原子质量的×1∕12（Kg） 1.9927×10-26kg×1∕12原子的相对原子质量=原子核内质子数 + 核内中子数如：氢原子的相对原子质量 = 1（质子数）+ 0（中子数）＝1氧原子的相对原子质量= 8（质子数）+ 8（中子数）＝16二、根据化学式的计算1、根据化学式计算物质的相对分子质量氢气的相对分子质量：Mr（H2）＝1×2＝2水的相对分子质量： Mr（H2O）= 1×2 + 16×1=182、计算化合物中元素的质量比化合物H2O2中，H、O两种元素的质量比= 1×2︰16×2 = 1︰163、计算化合物中某一元素的质量分数12×1例：化合物CH4中，碳元素的质量分数：C ％ = ————×100 = 75％12+1×41×4氢元素的质量分数：H ％ = ————×100 = 25％12+1×4或H ％＝ 100%－75% ＝ 25%三、关于溶液的计算公式1、溶液质量= 溶质质量+ 溶剂质量= 溶液质量×溶液密度溶质质量2、溶质质量分数= ——————×100％ .溶液质量溶质质量= 溶液质量×溶质质量分数= 溶液质量×溶液密度×溶质质量分数四、溶解度的计算公式溶质质量1、溶解度（S） = —————×100g（仅适用于饱和溶液）溶剂质量在饱和溶液中，溶质质量分数与溶解度的换算公式：面连小草也长不出来的。

高中化学溶解度积计算技巧

高中化学溶解度积计算技巧化学是一门需要深入理解和掌握的学科，其中溶解度积是一个重要的概念。

在化学实验和计算中，准确计算溶解度积对于解决问题和预测反应结果至关重要。

本文将介绍一些高中化学中常见的溶解度积计算技巧，并通过具体的题目来说明。

溶解度积是指在一定温度下，溶液中溶质溶解所达到的平衡状态下，溶质在溶液中的浓度乘积。

它的计算可以通过已知溶质的溶解度和溶液浓度来实现。

下面我们通过几个例子来具体说明。

例1：已知溶解度为0.02mol/L的AgCl溶解在浓度为0.1mol/L的HCl溶液中，求AgCl的溶解度积。

解析：溶解度积的计算公式为Ksp=[Ag+][Cl-]，其中[Ag+]和[Cl-]分别表示Ag+和Cl-的浓度。

根据题目中的信息，我们可以得到[Ag+]=0.02mol/L，[Cl-]=0.1mol/L。

将这些值代入计算公式，得到Ksp=0.02*0.1=0.002mol/L。

例2：已知溶解度为0.01mol/L的BaSO4溶解在浓度为0.02mol/L的Na2SO4溶液中，求BaSO4的溶解度积。

解析：在这个例子中，我们需要注意到BaSO4的溶解度积计算公式为Ksp=[Ba2+][SO42-]，其中[Ba2+]和[SO42-]分别表示Ba2+和SO42-的浓度。

根据题目中的信息，我们可以得到[Ba2+]=0.01mol/L，[SO42-]=0.02mol/L。

将这些值代入计算公式，得到Ksp=0.01*0.02=0.0002mol/L。

通过以上两个例子，我们可以看出溶解度积的计算方法是基于已知溶质溶解度和溶液浓度，并根据计算公式进行代入计算。

在实际计算中，我们需要注意单位的一致性，确保所有浓度的单位相同。

除了计算溶解度积，我们还可以利用溶解度积来预测反应结果。

当溶解度积大于等于某一特定值时，会发生沉淀反应。

以AgCl为例，其溶解度积为1.8*10^-10。

如果我们在实验中发现溶液中的[Ag+][Cl-]的乘积大于等于1.8*10^-10，那么就可以预测会发生沉淀反应，生成固体的AgCl。

h2在某些金属表面解离吸附热的近似计算

h2在某些金属表面解离吸附热的近似计算近年来，由于海水处理、冷冻分离、气体液化、储存及空调系统等应用的开发和进步，对氢气作用的理解和控制越来越重要。

一般来说，氢气在金属表面上能够解离自由吸附，并受到金属表面的吸引力而被吸附。

氢气吸附过程中伴随热量的放出，这种热量消耗是氢气吸附过程中必不可少的一环。

因此，精确地计算氢气解离吸附热对于正确预测氢气吸附过程中反应势及吸附速率等方面来说是十分必要的。

虽然在金属表面，目前已经有多种实验测量和理论模型来研究氢气的吸附反应和热量消耗，但是精确的计算氢气解离吸附热仍然是一项挑战。

直至最近，根据金属表面上的氢原子的化学结构特征，已经开发出一种近似的计算方法供氢气解离吸附热的计算。

这种新的计算方法通过构建表面上氢原子之间的类金属层来实现解离吸附热的计算。

构建类金属层的方法比传统的势能模型具有更高的精度，因此可以更准确地计算氢气解离吸附热。

首先，通过分子动力学模拟，可以准确地模拟出金属表面上氢原子间的环境。

获得的金属表面中的氢原子数据可以用来构建表面上的类金属层，这些类金属层可以实现准确的氢原子间的相互作用。

接着，此时可以计算出氢气在金属表面上的吸附能力，并计算氢气解离吸附热。

同时，此种近似计算方法还可以应用于其他金属表面对氢原子作用的情况，如锌表面、铝表面等。

参照金属表面氢原子的特征，可以准确构建表面类金属层，以获得精确的氢气解离吸附热计算结果。

此外，根据此种计算方法，可以计算出氢气解离吸附热时的氢原子的变化规律。

在金属表面上，当氢气被吸附时，表面上氢原子间的结构会发生变化，从而释放出一定量的热量消耗。

此种近似计算方法可以帮助研究人员更全面地了解氢气解离吸附过程中的物理机制及氢原子间的相互作用变化规律。

综上所述，基于金属表面的氢原子的化学结构特征，已经开发出一种近似的计算方法来实现氢气解离吸附热的准确计算。

此种计算方法利用金属表面中氢原子的数据构建表面类金属层，从而实现氢气解离吸附热的准确计算。

气体在金属中的溶解度

放热反应
能形成稳定氢化物
氮、氢在铁中的溶解度
在铁的气化温度附近，气体溶解度陡降。氮、氢在液态铁中的溶解度随温度升高而增大。氮、氢在金属凝固时溶解度陡降。氮、氢在奥氏体中的溶解度大于铁素体。
（ PN2 ＝PH2 = 0.1MPa ）
第II类金属吸氢过程是放热反应，因此随 a）着温度的升高，氢的溶解度减小，
1
溶解度
2
焊件中气孔的形成产应，溶解度随温度的固相更有利于气体的
上升而降低。溶解。生直接的影响。
温度气体溶解度与热效应和温度的关系 1－吸热溶解 2－放热溶解
2、氮、氢、氧在金属中的溶解度
氮和氢在金属或合金中的溶解反应类型及形成化合物倾向
气体金属与合金铁和铁基合金氮 Al、Ti、V、Zr等金属及合金 Fe、Ni、Al、Cu、Mg、Cr、Co 等金属及合金氢 Ti、Zr、V、Nb、Ta、Th 等金属及合金放热反应吸热反应不能形成稳定氢化物溶解反应类型吸热反应能形成稳定氮化物形成化合物倾向

双原子气体溶入金属液的两种方式：吸附 — 分解 — 溶入
分解 — 吸附 — 溶入
双原子气体溶入金属液的两种方式
温度不够高或气体难以分解时
焊接温度下氢、氧等气体的溶解
二、气体的溶解度
溶解度 —— 在一定温度和压力影响因素
气体种类合金成分
氢溶解度 SH/ ml. (10 0g)
-1
3、合金成分对溶解度的影响
氮溶解度 SN/ ％
合金元素含量wMe /% 氢在二元系铁合金中的溶解度（1600℃）
合金元素含量wMe /% 氮在二元系铁合金中的溶解度（1600℃）