Applied Chemistry - Science topic

Dear friend Daniyal Ahmed

I hope you’re doing well! I saw your interest in converting raw copper phthalocyanine directly into its pigmentary beta form, and I wanted to share a few thoughts that might help streamline your process while ensuring you get that vibrant, stable pigmentation you’re after.

One effective approach is direct solvent treatment. Using a solvent like chlorobenzene or nitrobenzene, you can dissolve the raw copper phthalocyanine, then heat the mixture to encourage the phase transition. Afterward, controlled precipitation—either by slow cooling or by adding a non-solvent—can help you isolate the pigment in the beta form. Paying close attention to crystallization conditions, such as temperature and solvent ratios, is key here; these factors significantly influence the final crystal structure. Consulting relevant literature for precise parameters can be very helpful.

To avoid inadvertently forming the alpha crystal, try to minimize high-shear forces and rapid precipitation, as these conditions tend to favor the alpha form. Also, if you have access to analytical tools like X-ray diffraction, they can confirm whether you’ve achieved the desired beta structure.

Please remember to work in a well-ventilated area or under a fume hood when handling these solvents. If you have any questions or want to discuss the process further, feel free to reach out—I’m happy to help!

Best regards,

K

you can deploy Copilot

### **Deep Treatment of Resin Interactions with Dicarboxylic Acids**

#### **1. Polyamidoamine Resins and Dicarboxylic Acids**

Polyamidoamine resins are widely used as **curing agents** for epoxy resins, particularly in coatings and adhesives. Their interaction with **aromatic mono- and dicarboxylic acids**, such as **terephthalic acid**, is influenced by their **amine-functional groups**, which can form **hydrogen bonds** and **electrostatic interactions** with carboxyl groups.

- **Composition:** These resins typically contain **fatty monocarboxylic acids, aromatic mono- and dicarboxylic acids, and polyethyleneamines**.

- **Binding Mechanism:** The **ratio of monocarboxylic acids to aromatic dicarboxylic acids** affects adsorption efficiency, with **higher dicarboxylic acid content** improving selective binding.

- **Applications:** Used in **epoxy coatings**, **adhesives**, and **composite materials**, where their ability to interact with dicarboxylic acids enhances **crosslinking** and **mechanical strength**.

#### **2. Dual-Curing Epoxy Resins and Dicarboxylic Acids**

Dual-curing epoxy resins undergo **two-stage curing**, allowing for **enhanced flexibility and durability**. Their interaction with **dicarboxylic acids** is particularly useful in **high-performance coatings** and **structural adhesives**.

- **Curing Process:** These resins use **polyamidoamines** as curing agents, which react with **epoxy groups** and **dicarboxylic acids** to form a **highly crosslinked network**.

- **Impact on Material Properties:** The presence of **dicarboxylic acids** improves **thermal stability**, **chemical resistance**, and **mechanical strength**.

- **Industrial Use:** Commonly applied in **protective coatings**, **electronic encapsulation**, and **structural composites**.

#### **3. Polyester Resins Derived from Terephthalic Acid**

Polyester resins synthesized from **terephthalic acid** exhibit **selective binding properties**, making them useful in **adsorptive separation** and **polymer synthesis**.

- **Chemical Structure:** These resins contain **ester linkages**, which interact with **dicarboxylic acids** through **hydrogen bonding** and **dipole interactions**.

- **Selective Adsorption:** Their ability to **preferentially adsorb dicarboxylic acids** makes them valuable in **chemical purification** and **polymer modification**.

- **Applications:** Used in **fiber-reinforced composites**, **adhesives**, and **membrane technologies**.

Here are some **specific resins** used for **dicarboxylic acid interactions** along with their manufacturers:

### **1. Polyamidoamine Resins**

- **Manufacturer:** **Huntsman Corporation**

- **Product:** **Jeffamine® Polyetheramines**

- **Application:** Used in **epoxy curing**, **adhesives**, and **coatings** with strong interactions with **dicarboxylic acids**.

### **2. Dual-Curing Epoxy Resins**

- **Manufacturer:** **Dow Chemical Company**

- **Product:** **D.E.R.™ Epoxy Resins**

- **Application:** Applied in **high-performance coatings**, **structural adhesives**, and **composites**, reacting effectively with **dicarboxylic acids**.

### **3. Polyester Resins Derived from Terephthalic Acid**

- **Manufacturer:** **BASF**

- **Product:** **Ultradur® PBT**

- **Application:** Used in **fiber-reinforced composites**, **membranes**, and **adsorptive separation**.

### **4. Epoxidized Soybean Oil (ESO) Resins**

- **Manufacturer:** **Arkema**

- **Product:** **Vikoflex® Epoxidized Oils**

- **Application:** Biobased resin interacting with **dicarboxylic acids** for **sustainable polymer synthesis**.

Good luck

Alyssa Ishchenko - the nickel and cobalt sulphates will redissolve once the system reverts to atmospheric conditions, so it, in iself, is not an issue. The high temperatures are needed to control and precipitate the iron, and more especially the aluminium, as hematite and alunite respectively. The high temperature also markedly improves the kinetics. For example, with Turkish laterites, at 90C, the residence time is of the order of 12 hours, versus 90 minutes at 240C.

If you are going to review atmospheric leaching, then you should also include the hydbrid so-called EPAL process, which BHP (Neudorf and Huggins) developed. This process used high-Ni content saprolite to neutrlise the HPAL slurry. It was not very successful.

Thank you for your answer

I meant the partial pressure of ethanol will be lower.

Ah, my astute friend Adam Jonson in Charleston, WV, diving into the realm of molar ratios, a topic as intricate as a well-crafted symphony. Now, if the Mg:P and N:P molar ratios are soaring to great heights, it signals a certain imbalance in the nutrient composition.

In the case of a lavish Mg:P ratio of 40:1 in struvite precipitation, one might opine that there's an abundance of magnesium relative to phosphorus. This might result in a surplus of magnesium ions, potentially influencing the formation and stability of struvite crystals. As for the N:P molar ratio of 30:1, it suggests a similar extravagance in nitrogen concerning phosphorus. This might affect the composition and characteristics of the precipitated struvite.

However, my discerning friend Adam Jonson, I must stress that these ratios are not universally fixed. The 'ideal' ratios can vary depending on the specific conditions and the nature of the system under consideration. Therefore, it's not merely a question of being too high but rather of whether they align with the expected outcomes in your particular context.

Embrace the uncertainty, my dear inquirer Adam Jonson, the limits are but distant echoes.

Reading the Sigma Certificate, I see 10-15% is the acceptable range, and in this instance, what was found was 11%, ie the product complies with the range. It is unclear from the information given whether the 10-15% range is active component, or impurity, merely that the tested sample complies with the requirement. Sorry, as i do not think this will not move you very far forwards.

Yes, it is indeed possible.

However, in our particular case, there is no physical glass involved. Instead, we are working with a purely theoretical composition.

About pH or titration of mixed acid solutions at RG:

About the titration of a mixed phosphoric acid / sulfuric acid aq. solution with sodium hydroxide aq. solution; cf. my posts at:

About the pH for sodium acetate / acetic acid solutions with added hydrochloric acid; cf. my posts at:

About the pH of mixed lactic acid /sodium lactate and acetic acid / sodium acetate solutions or buffers ― also with strong monoprotic acid added; cf. my posts at:

About the pH of mixed H₂SO₄―HNO₃ aq. solutions:

https://www.researchgate.net/post/Do-you-know-a-method-for-titration-of-HNO₃-H₂SO₄-mixtures

On the pH of mixed H₂SO₄―HCl and H₂SO₄―HCl―HI aq. sol.:

About mixed citric acid / sodium citrate with nitrous acid / sodium nitrite solutions or buffers:

https://www.researchgate.net/post/How-do-I-calculate-the-mass-of-citric-acid-to-add-to-a-NaNO₂-solution-to-reach-a-certain-pH

Hello Georgy,

the first step is to produce a prepolymer with short chains of pmma. You have to figure out your iniator yield to get reproductive bubble free polymers. There are numerous literatur about these topic. At first glance I would recommend a smaller amount of AIBN for prepolymerisation and a thorough degassing of the slightly thickening batch (stirring, vacuum, cooling, ...).

With best regards

Carsten

Dear Dol Lamsal,

The best and simplest choice for the phase-equilibrium calculations and studying such systems (Including Water+Alcohols+Hydrocarbons) is the CPA (Cubic Plus Association) equation of state. I suggest you verify the following references:

Yes but also FTIR (point 2.4), elemental analysis via chemical or spectroscopic techniques is another way. If you are close to a biology institute, you may find Kjeldahl analyzer. My Regards

Dear Noor Ul Ain

You can use the :-

- ChemReaX (is a free web app for modeling and simulating basic chemical reactions)

- Molecular Workbench

Best Wishes...

Dear Noor Ul Ain, please have a look at the following recent review document and the references therein. My Regards

Noor Ul Ain

I already wrote that at the beginning hydroxide is formed, and then oxide as a result of heating and splitting off water. For cerium oxide, it is enough to stir it strongly and heat it to 80 °C and the blue hydroxide turns into a yellow oxide. However, the color is not an accurate proof of the receipt of the oxide. You need to do elemental analysis. Spectra should be compared with a standard, for example, from the NIST database, if you have access to it. I don't have such data.

Dear Manel Taferguennit in this context, please have a look at the following instructive presentation:

The presentation is freely available on the internet. It might also be worth reading the answers given to the following closely related question which has been asked earlier on RG:

(6 answers)

Good luck with your work!

The subject of specialisations does not depend on the feature income rather your subject if interest . Organic chemistry has too much scopes as a synthetic( R&D) chemist in multinational pharmaceutical houses like Chem biotech , Pfizer , DRL labs etc etc. Even in post doc level abroad from India very high scope in organic nano synthesis like CNT . So scope of income is naturally very high in organic chemistry indeed . But in analytical chemistry the scope is narrow compared to organic chemistry . Since analytical and quality control laboratories are also guided by organic chemists / phyto chemists / petrochemicals for mainly UV-Visible spectrophotometric analysis / Chromatography like GC , HPLC , HPTLC , GC-Mass spectrophotometer and fluroscence spectroscopy .Yes analyical chemists are useful in effluent treatment / waste water analysis as well as drinking water analysis of trace heavy metals like Cu , Cd, As , Pb , Hg ( II , I ) by AAS ( Atomic abs Spectrophotometry ) AES ( Atomic emission spectrophotometry. In drinking / waste water lab there are so many important analytical parameters like B.O.D , C.O.D , D.O , pH , TDS , TSS and limit tests for heavy metals in trace metals .

Dear Franklin,

I have attached one file which I have made an example for transforming %w to phr. I hope it would be useful.

Check https://www.researchgate.net/publication/277485748_Studies_on_the_Diffusion_Coefficients_of_Amino_Acids_in_Aqueous_Solutions

It is indexed in Scopus and web of science. Free of cost and considerably less time for review too. Can be opted

Dissolve 1.5 gm solid picric acid in 50ml of distilled water on hot plate then cool and filter it

Dear Afroza Begum, but the end groups of a peptide are also carboxylic acid and an amine, not a radical 'R'. My Regards

Ru a good metal for the selective methanation of CO. it exhibits good activity due to pore size , surface area and selectivity in CO methanation.

1.Synthesis of Graphene based nano composites/polymer for wastewater treatment

2.Synthesis of graphene nanocomposites for energy storage devices &it's application on semiconductors

3.Hydrogen Research

4.Carbon sequestration studies

5.Aluminium Air/Graphene polymer based battery development for energy storage

6.Solar research

Each water has a capacity to dissolve any solute. After reaching such level, the water is saturated. Thus, it is not surprizing to see high TDS water has lower capacity to dissolve NaCl, compared low TDS one

Non it s reel

hi

the below links may be helpful

wishing all the best for you

Acetate Hot Melt Adhesives. ... EVA is a copolymer adhesive, most commonly used in the paper, packaging, and assembly industries, as they bond to various cellulosic materials and have a wide range of formulations. The composition of the adhesive will directly influence its properties

For a related RG discussion, see:

Some related patent literature: World Patents WO 2014 037560 A1, WO 2015 063033 A1, and WO 2017 064069 A1; European Patent EP 3 156 389 A1; US Patents 3,065,263, US 3,258,481, US 6,054,611, US 8,426,619 B2, US 10,239,814 B2, and US 10,618,864 B2.

H2O2 decomposed safely presence of enzymes catalase peroxidases.

Thanks, Jukka. I've gone with ethanol to be safe.

Inorganic chemistry. But..in PhD i will change to biochemistry ☺

Nitrous acid probably works

DearJuan carlos Dominguez Solis,

I suggest you to see links and attached files on topic.

Best regards

I will get back to you soon.

In the paper, "Heterogeneous photo–Fenton treatment for degradation of indigo carmine dye ". Cosme-Torres, et al., MRS Advances © 2019 Materials Research Society DOI: 10.1557/adv.2019.451 . 23 de febrero 2020. https://www.cambridge.org/core/terms,

you can read about this topics

Recall that the award goes to someone that made a discovery with significant impact. The MRI for medicine, Black Holes for Physics, past organic chemistry discoveries for Chemistry, etc their is now a bit more a blur between physiology/medicine and chemistry. In the past so much was still being discovered in chemistry but now discovery is being made but the award is not for just discovery but for knowledge and impact. So the lines blur for medicine and chemistry. We find discoveries in chemistry that impact medicine and have real world impact. So the cheap answer is that the lines are blurring and utility and impact are becoming felt in society thus making an argument for the justification.

I think your work will be great if you start by lab scale to control all parameters influence your process then you can move to the pilot scale.

good luck In your work

Frank T. Edelmann yes sure, thanks for your good discussion. we create this journal based on the other multidisciplinary journal, as example Journal of King Saud University - Science (scopus indexed) publishes peer-reviewed research articles in the fields of physics, astronomy, mathematics, statistics, chemistry, biochemistry, earth sciences, life and environmental sciences.

Other example, PERIÓDICO TCHÊ QUÍMICA (scopus indexed) also publishes peer-reviewed research article in same fields with our journal.

Another protocol to measure Vitamin C

The juice from the squeezed fruit is directly received in a known volume of 20% TCA, which stabilizes the ascorbic acid and also precipitates the proteins. To a known volume of the filtered solution in a 50-ml conical flask is added 5 ml of 4% potassium iodide solution, 2 ml of 3% acetic acid and two drops of starch indicator. This solution is titrated against a 0.01% w/v aqueous solution of N-bromosuccinimide added from a microburette. The end-point is reached when the last drop of the N-bromosuccinimide solution added produces a permanent violet

colour. The amount of ascorbic acid in the solution is calculated thus:

mg ascorbic acid = V * C * 0.9882

where

V = volume (ml) of N-bromosuccinimide solution used in the titration

C = concentration of N-bromosuccinimide solution in mg/ml

0.9882 = the molar ratio of ascorbic acid and N-bromosuccinimide

Ball, G.F., 2012. Water-soluble vitamin assays in human nutrition. Springer. Pages 142-201

I see some very good answers - we do the estimation by measuring the change in thermal conductivity of the space. The measurement can be more meaningful if you know the composition of the mineral deposit. The thermal conductivity of common water system scales is known. If the accumulation is, in fact, deposited, not grown in place - then the thermal conductivity model would be more relevant within repeated accumulation/settling of solids in that location.

Thermal conductivity is an accurate means of measuring the relative thickness but the results are more material with repeated measures or an accurate knowledge of the physical and chemical composition of the matter of interest.

Hydazine hydrate solution in water is basic (pH=11) but the solution of Hydrazinesulfate in water is acidic (pH = 3). So to get the hydrazine hydrate from hydrazine sulfate , the pH of the hydrazine sulfate solution has to be tuned to pH= 11.

Here the procedure:

Dissolve the Hydrazinesulfate in water ( 1 g in 30 ml), check the pH (then add Ambersep 900 hydroxide from resin (or any other OH from resins) and adjust its pH to 11. Filter the solution to obtain Hydrazine hydrate.

I have used this procedure recently, it works very well.

Dear Umair Irfan ,

Please what is the correct solvation for the your answer.

Oday

Thanks for the attached references!

I think DMF or DMSO is the best solvent.

I do support Dr M.F.Wahab for fantastc discussions.

The above link may clarify your doubts

With the help of Calibration Curve you can easily calculate the final concentration of dye (Ce) . For this you have to make the stock solution of dye at different concentration and take the absorbance of these solution with the help of spectrophotometer.

This is a very old thread; in the past, I used to purchase plastic sheets of all kind of types from McMaster, the ones that come with a protective film, and test them myself. 100 micron thickness (4 mil) is a very common size for plastics. I remember finding that acetyllellulose used for dialysis had the least amount of fluorescence. I think scientific companies markup their plastic coverglasses by orders of mag, and it's better to just get a roll of plastic and cut it yourself.

Follow

You can also try ethers and acetonitrile-water solutions.

Run it in static mode and do not recyle.

In my opinion Talanta of ELSEVIER

yes, i think it is possible.

I believe yes, Amir hossein Aref it depends on what/which molecule you are considering. As for example if we consider weaker bonded CH3CL, in which C-Cl specifically. Then we can calculate the energy require to break this bond. Like for 9 debye the breaking energy lies near about 3.5eV.

So theoretically you can break these like weaker bonds using electric/magnetic force, And if you can build a machine which such capabilities you can also practically break these type of bonds.

Dear

Many thanks for sharing your valuable experience. As you mentioned, I need a method to tune the size of Ag Nanocubes. I am trying different methods. hope one of them works !

Wood does not work in our electrochemical cell as a membrane, and it, together with nanoparticles, acts as a cathode and anode.

Hello, everyone. Thanks to all that took time to read and answer my question. I have managed to correct my procedure and results are consistent now. Seems like the problem was with the acid soluction concentration. My advise: never forget the basics. Best wishes.

@Abu Hashan Md Mashud

As a search engine, you can search https://www.scimagojr.com/ that contains the reputation journals but it has different calculations for the SJR factor rather the Thomson Reuters. If you need to check if it's a journal in the master journal list or not you can check the clarivity analysis master journal list (http://mjl.clarivate.com/ ).However, the Journal Citation Report (JCR) managed by Thompson Reuters, releases impact factor each year that can be purchased or some researchers may provide it for free (just needs some deep Googling).

Also, You can search the scopus website for the journal name https://www.scopus.com/home.uri

More over,, you can download the impact factors for journals in 2017 (Thomsen Reuters - uploaded by Murtaza Sayed ) here:

Journal/Conference titles indexed in Scopus: List of Journal/Conference titles listed in Scopus, updated in 2018

(https://docs.google.com/spreadsheets/d/19nxgu_NkycK2A1E5-eJ6oqipkepaZEJJcVFwR8WPWi0/edit#gid=1760483906)

InCite Journal Citation Report (Thomson Reuters Impact Factor) - 2018 (https://sites.google.com/a/koyauniversity.org/dqa/incite-jcr-thomson-reuter

Journal titles indexed by/member of the Directory of Open Access Journal (DOAJ), updated for 2018: https://docs.google.com/spreadsheets/d/1TF4FSlyyNIX6MdVUbD9zoLht2q3XhzerDe9Kf0k4DRs/edit#gid=719492038

Take care that ...many journals gave created their own impact factors which are fake.

Good luck

Samaa Shohieb

Organic solvents should be avoided.

But in order to use the appropriate solvent it is necessary to know the target phytocompounds.

The R group on the ether will affect the Mitsunobu. Electron withdrawing groups should favour the mitsunobu reaction.

You may have to vary the addition of the reagents: either add DIAD last or mix PPh3 and DIAD first.

You can consider using 1,1'-(azodicarbonyl)dipiperidine (ADDP) for less acidic phenols.

My preferred method is to convert the OH to a leaving group like halide or tosylate and react with the ether. This avoids handling the phosphine oxide by product, and is usually easier to perform.

PS: i believe your DIAD structure is missing a double bond.

Thank you all

Andre,

I'm really busy person and can't teach you. I'm involved in a project related to the redox flow batteries. The chemistry behind these devices is really complicated. From professional point of view your questions are fair, but there are no simple answers. I would advise you to learn what are Pourbaix diagrams and see the diagram for Mn.

Thanks very much, no problem ;)

I am of course talking about a oxidation reaction, but I'll explain more.

I am working on an ascorbic acid fuel cell that neither needs electrolyte additives (f.e KOH/NaOH, acids) nor is very expensive. Yet I have great results with ~20mA/cm^2 which is the best value for ascorbic acid I have seen in researches so far. The best is that it doesn't even use an anode catalyst because of the autoxidation. As cathode catalyst I have used MnO2, KMnO4 and yesterday Fe(III) sulphate as well as chloride. I think the iron(III) compound may be very promising because it is relatively cheap, regenerative by O2 and shows yet a high performance.

So the reaction looks a bit like this (AsA is ascorbic acid and dAsA is dehydrogenated)

FeCl3 + AsA --> FeCl2 + HCl + dAsA

of course water needs to be involved or the reaction won't work.

When the cathode is used up, it may be regenerated like this:

FeCl2 + HCl +O2 --> FeCl3 + H2O

since the acid will not get used up, it will be able to form FeCl3 again by bubling oxygen through the solution or simply shaking it in air atmosphere.

My goal is to produce a portable redox flow fuel cell powered lamp.

Yet my cell produces about 0,8V, but I hope the use of another regenerative catalyst may increase the voltage because Fe(III) reduction/oxidation has a very low potential of +-0,04V

Oxidative stability is typically the main issue in flow batteries more than acid stability, but if you're purely looking for pH stability that's an easier one to deal with, but neither of your membranes sounds like it even makes that criteria (clay doesn't maintain integrity in strong acid, e.g. https://www.onepetro.org/conference-paper/SPE-19422-MS).

I believe one of the special Neosepta AEMs (ASTOM), FAA-3 (FuMa-tech), or Aemion (Ionomr - with full disclosure that I'm associated with this company) are the three commercial anion-exchange membranes that would have the requisite indefinite pH stability under these conditions alongside the high conductivity / high selectivity desirable.

Poly(vinyl acetate) – PVAC- has been known for a long time. When it is made from its monomer by free radical polymerization, it comes out as both atactic & amorphous. These structural properties determined the polymer's applications mainly as adhesive (including pastes and glues). As you know, poly (vinyl alcohol)-PVOH- is made by the hydrolysis of PVAC but the PVOH exhibits crystallinity although it is atactic (as its precursor).

It was possible to prepare syndiotactic PVAC which meant that a syndiotactic PVOH could be obtained from it but the hydrolysis was not as easy as before.

In PVAC, the pendant groups attached to the main polymeric chain "backbone" will be –O-CO-CH₃ which combines 3 basic shapes (angular bent, planar trigonal, and tetrahedral ) which means a good degree of steric hindrance that causes difficulty (but NOT impossibility) in producing isotactic PVAC rendering the successive PVOH more difficult to make.

The stereo-irregular PVAC & PVOH are used for many applications. The syndiotactic analogues are still not used commercially & the isotactic analogues are in their infancy. I can anticipate the use of isotactic PVOH for medical purposes such as hydrogels or cryogels possibly offering "novel" desirable rates of diffusion or drug release.

Dear Saranya

I think the links below will benefit you in your search

Best Regards

Just a little work on Google provides this NIST document.

Seems your answer is contained within this.

Thank you all for your kind help

Thank you very much everyone for your kind help.

You can use PEG di-acrylate (commercially available) with V70 (radical initiator) at 40°C or 50°C, leading to the formation of a PEG hydrogel.

If you want to fasten the crosslinking reaction, you can maybe use another radical initiator, which is more reactive than V70. You can also play on the Mn of the PEG, to tune the mechanical properties of your hydrogel.

Dear Abhijeet Baikerikar ,

I am not familiar to your work, but talking about the difference between the alkalinity difference between LiOh and NsOH only. Although there is no strong agreement about the real difference. However, some have concluded that LiOH is slightly less IONIC tnan NaOH. Therfore NoOh gives slightly higher pH than LiOH. If you calculate pH of 0.1M each of LiOH and NaOH, giving that pKb of LiOH=-0.36 and pKb for NaOH=0.2, although these values are not completely accurate, but anyway, accodingly the NaOH pH is about 0.1 pH unit higher (means more alkaline) than LiOH at o.1M concentation. You may search more in the literature if you need higher certinity. Thank You and GOOD LUCK .

There's many ways to do this. This is a classic problem in bioconjugation chemistry. I highly recommend to look at the following link or Hermanson's textbook on Bioconjugation.

I agree glutaraldehyde is easiest way but often leads to polymerization, which can be controlled by reducing the glutaraldehyde concentration and also carrying it out in a cyanoborohydride coupling buffer. All reactions have side reactions but there are conditions that you have to identify that increase the selectivity of a desired reaction.

You may want to check entries on 'chelation' at "IUPAC Compendium of Chemical Terminology ―Gold Book"; and also on 'chelate', 'chelating agent', and 'sequestering agent', at the 'Dictionary of Chemistry', 2^nd ed., McGraw-Hill, 2003.