Will Vanadium take the pressure off Lithium (prices)?

Read more in references below:

Fraunhofer-Gesellschaft_Dipl.-Ing. FH Jens Noack of Fraunhofer-Institut für Chemische Technologie
summarises their work on improved redox flow batteries for electric cars (Research News October

A new type of redox flow battery presents a huge advantage for electric cars. If the rechargeable batteries are low, the discharged electrolyte fluid can simply be exchanged at the gas station for recharged fluid – as easy as refilling the petrol tank.

The principle of redox  and redox flow batteries is not new – two fluid electrolytes containing metal ions flow through porous graphite felt electrodes, separated by a membrane which allows protons to pass through it. During this exchange of charge a current flows over the electrodes, which can be used by a battery powered device.

Until now, however, redox flow batteries have had the disadvantage of storing significantly less energy than lithium-ion batteries. The vehicles would only be able to cover about a quarter of the normal distance – around 25 kilometers

 – which means the driver would have to recharge the batteries four times as often. “We can now increase the mileage four or fivefold, to approximately that of lithium-ion batteries,” Noack enthuses. The researchers have already produced the prototype of a cell. Now they must assemble several cells into a battery and optimize them. This further development is being carried out with colleagues from the University of Applied Sciences, Ostphalia, in Wolfenbüttel and Braunschweig. They are testing electric drives and energy storage units on model vehicles that are only a tenth of the size of normal vehicles.



Thanking also
New Energy and Fuel_online website
NB.
"Keep in mind the redox electrolyte research is just now getting under way and the claim is to meet the lithium ion standards very soon. There is even room for opportunities in research at the anode and cathode. What remains of great interest is the energy per weight and volume numbers that can really enthuse or befuddle the future."

& Comment

"Vanadium liquid electrolyte batteries are well-developed, maybe don’t quite have the energy density for automotive use. Here is a good review article on vanadium batteries: http://www.scribd.com/doc/20283743/Status-of-the-Vanadium-Redox-Battery-Development-Program"


en référence à : Improved redox flow batteries for electric cars - Research News 10-2009-Topic 7 – Fraunhofer-Gesellschaft (afficher sur Google Sidewiki)

Zeolite Sebagai Pelapis Biokompatibel dan Antikorosi

Jutaan orang di seluruh dunia telah merasakan keuntungan dari kemajuan teknologi di bidang ilmu pengetahuan dan obat-obatan. Ilmu pengetahuan telah melahirkan teknologi komunikasi yang lebih baik dan transportasi untuk globalisasi. Sementara itu peningkatan pemahaman tubuh manusia telah meningkatkan harapan hidup dan perbaikan kualitas hidup. Tidak diragukan lagi bahwa pemahaman yang baik mengenai nanoteknologi, ilmu material, dan biologi molekular akan membantu dalam memecahkan masalah ilmiah saat ini.

Salah satu masalah yang memerlukan kolaborasi ahli teknik, ilmuwan material, dan dokter adalah bahwa untuk menciptakan bahan bio-kompatibel yang dibutuhkan untuk implan bagi pasien gigi dan ortopedi. Bioimplants sering digunakan untuk pengobatan berbagai luka dan penyakit. Penggunaan implan ortopedi logam secara luas telah meningkatkan kualitas hidup bagi jutaan orang. Namun implan ortopedi rata-rata hanya bertahan selama 10-15 tahun. Kebutuhan akan operasi penggantian implan menurunkan keberhasilan dalam proses implantasi karena adanya peningkatan luka jaringan dan infeksi. Hal ini berkorelasi dengan umur pasien dan penurunan kapasitas mineralisasi pada kerangka manusia.

Alasan utama pendeknya ketahanan implan adalah kurangnya osteointegration dalam implan. Sifat korosif cairan biologis bersama dengan beban siklis akibat gerakan mempercepat kegagalan implan. Untuk mengatasi masalah-masalah dalam implan medis memerlukan material dan tahapan produksi yang mahal.

Pengembangan material komposit baru yang memiliki kombinasi yang tepat kimia, biologi mekanik dan sifat dapat menghasilkan biomaterial yang sangat baik untuk digunakan sebagai implan. Cairan tubuh manusia mengandung ion-ion Na+ dan CI- dalam jumlah besar bersama dengan ion karbonat yang dapat menyebabkan pelarutan elektrokimia. Produk Korosi dapat menyebabkan reaksi peradangan setempat dan dapat masuk ke aliran darah dan menyebabkan reaksi alergi dari sistem kekebalan tubuh. Dengan demikian, stabilitas kimia adalah sangat penting untuk biomaterial selain sifat nontoksisitasnya. Bioimplants juga harus menunjukkan kekuatan mekanik yang tinggi untuk mencegah kegagalan oleh gaya muskuloskeletal. Meskipun banyak logam memiliki sifat mekanik yang baik, kebanyakan sangat rentan terhadap korosi dalam tubuh manusia. Di antara pilihan terbatas untuk biomaterial, titanium dan paduannya bersama dengan paduan cobalt-chromium telah digunakan sebagai implan ortopedi karena bersifat inert. Namun karena biaya tinggi, kebutuhan akan perawatan fabrikasi khusus, ketahanan aus yang rendah, dan kerapuhan mendorong ditemukannya biomaterial baru.

Beberapa bahan telah dikembangkan untuk meningkatkan pertumbuhan jaringan pada implan logam yang akan menutupi logam. Dalam kasus implan ortopedi, bio-keramik, bio-kaca, coating organik, hidroksiapatit, dan coating karbon nanotube telah digunakan untuk menumbuhkan sel-sel tulang pada implan logam. Sebagian besar penelitian lapisan biokompatibel saat ini terfokus pada modifikasi permukaan logam untuk mencapai ketahan korosi, sifat mekanik, dan bio-kompatibilitas yang diinginkan.

Zeolit merupakan polimer kristal anorganik yang tersusun atas atom Si, Al dan O. Pada tingkat atom, zeolit dibangun dari TO4 tetrahedral (T = Si dan Al) dimana setiap atom oksigen apikal dibagi di antara dua tetrahedra yang berdekatan. Zeolit memiliki struktur mikroporous berukuran seragam, dan telah secara tradisional digunakan sebagai katalis dan media pemisahan. Zeolit mempunyai sifat tidak beracun dan telah digunakan sebagai agen pembawa dan pengontrol pelepasan beberapa obat. Zeolit dengan kadar silika 100% (tanpa alumina) telah terbukti sangat tahan korosi di asam kuat, basa kuat dan media agresif korosi sumuran (misalnya, larutan NaCl). Zeolit menunjukkan adhesi yang sangat baik untuk substrat berbagai logam (Al, baja, Cu, Ni), dan dikenal memiliki stabilitas termal, kimia dan mekanik yang baik. Zeolit juga kedap untuk semua gas, dan tidak bereaksi dengan asam mineral kecuali asam HF. Sifat permukaan (misalnya, hidrofilik atau hidrofobik) dari lapisan zeolit dapat mudah dikendalikan. Coating zeolit hibrid juga telah dibuat dengan bahan anorganik lain dan menunjukkan potensi besar untuk membuat lapisan komposit biokompatibel. Sebuah lapisan komposit dengan ketahanan korosi, stabilitas mekanik, dan biokompatibilitas yang tinggi dapat menghilangkan kebutuhan akan paduan titanium yang mahal dan menggantinya dengan baja stainless yang lebih murah.

Back to square one..; sorry recalibration of ZERO TIME_Time Metrology

An alternative title must be that cry of relief from the publican or barman "TIME's UP, Gentlemen please..."

Nothing like a bit of fundamental physics to keep our wits sharp.

TIME MEASUREMENT-UP DATE from Science

Perspectives
Physics:
When Does Photoemission Begin?
H. W. van der Hart

The process of photoemission was one of the effects that led to the formulation of quantum mechanics. If an atom or surface absorbs sufficient energy from incoming light, it can transfer that energy to an electron, which is then emitted. Theories of photoemission mainly focus on energetics—the temporal or dynamic aspects are ignored—but complex electron interactions occur that will create a slight delay between light absorption and electron emission. This time delay has been poorly understood for a fundamental reason: We cannot "see" an atom absorbing a photon. At best, we can follow subsequent emission events and use them to establish a "time zero" when the light was absorbed. A practical challenge has been that the time delay is extremely short, and only recently have direct experiments been feasible with the advent of lasers that emit pulses on the attosecond (as, 10–18 s) time scale. On page 1658 of this issue (1), Schultze and co-workers present measurements of time delays between different photoemission processes generated by the same ultrashort light pulse. This finding not only allows further studies of the timing of photoemission but also provides a new way to investigate electron interactions in atoms.

Centre for Theoretical Atomic, Molecular, and Optical Physics, School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, UK.



Delay in Photoemission
M. Schultze,1,2,* M. Fieß,2 N. Karpowicz,2 J. Gagnon,1,2 M. Korbman,2 M. Hofstetter,1 S. Neppl,3 A. L. Cavalieri,2 Y. Komninos,4 Th. Mercouris,4 C. A. Nicolaides,4 R. Pazourek,5 S. Nagele,5 J. Feist,5,6 J. Burgdörfer,5 A. M. Azzeer,7 R. Ernstorfer,3 R. Kienberger,2,3 U. Kleineberg,2 E. Goulielmakis,2 F. Krausz,1,2 V. S. Yakovlev1,2,*

Photoemission from atoms is assumed to occur instantly in response to incident radiation and provides the basis for setting the zero of time in clocking atomic-scale electron motion. We used attosecond metrology to reveal a delay of Formula attoseconds in the emission of electrons liberated from the 2p orbitals of neon atoms with respect to those released from the 2s orbital by the same 100–electron volt light pulse. Small differences in the timing of photoemission from different quantum states provide a probe for modeling many-electron dynamics. Theoretical models refined with the help of attosecond timing metrology may provide insight into electron correlations and allow the setting of the zero of time in atomic-scale chronoscopy with a precision of a few attoseconds.

1 Department für Physik, Ludwig-Maximilians-Universität, Am Coulombwall 1, D-85748 Garching, Germany.
2 Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Straße 1, D-85748 Garching, Germany.
3 Physik Department, Technische Universität München, James-Franck-Straße, D-85748 Garching, Germany.
4 Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, Athens 11635, Greece.
5 Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria.
6 Institute for Theoretical Atomic, Molecular and Optical Physics (ITAMP), Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA.
7 Physics and Astronomy Department, King Saud University, Riyadh 11451, Saudi Arabia.

More time...
More time...

Fire Retardant pada Polimer

Sekarang ini bahan polimer telah digunakan secara luas menggantikan bahan logam di kehidupan kita sehari-hari karena bahan polimer lebih murah dan ringan. Namun bahan polimer mempunyai satu kelemahan besar yaitu sangat mudah terbakar. Untuk mengurangi sifat dapat terbakar (flammable), pemahaman yang baik tentang mekanisme pembakaran polimer diperlukan.

Ada empat tahap utama yang terlibat dalam pirolisis dan pembakaran polimer. Proses pembakaran bahan polimer biasanya dimulai dengan pemanasan pada suhu di mana mulai terjadi degradasi termal; tahap pertama ini disebut sebagai tahapan pengapian (ignition step). Pada tahap kedua, atau tahap pirolisis, polimer yang terdegradasi melepaskan molekul-molekul kecil yang mudah terbakar. Pada tahap ketiga, disebut sebagai langkah pembakaran, molekul-molekul kecil yang dihasilkan pada langkah sebelumnya bergabung dengan oksigen dan terbakar, menghasilkan asap dan panas. Panas yang dihasilkan pada langkah ketiga sebagian kembali ke polimer (feedback step) dan siklus terus terjadi hingga seluruh polimer terbakar. Dengan memperlambat salah satu dari tahapan-tahapan tersebut akan menurunkan sifat flamabilitasnya.

Penurunan sifat flamabilitas dari polimer dapat melalui penambahan senyawa tahan api (fire retardant). Fire retardant bekerja dengan cara mendinginkan, membentuk lapisan protektif atau melalui pelepasan air dan atau CO2. Fire retardant yang biasa digunakan adalah hidroksida logam, senyawa posporus, senyawa yang mengandung halogen dan clay.

Metal hydroxides
Filler anorganik menghambat pembakaran polimer dengan membuang panas dari polimer dan mengurangi suhu api. Contohnya adalah aluminium oksida hidrat, Al2O3.3H2O dan magnesium hidroksida, Mg(OH)2. Senyawa ini di dalam nyala api akan mengalami dekomposisi secara endotermik (menyerap panas), dan melepaskan sejumlah besar uap air ke permukaan polimer. Air akan melarutkan gas yang mudah terbakar. Salah satu kelemahan dari bahan-bahan tersebut adalah bahwa kadar yang tinggi diperlukan untuk mendapatkan sistem tahan api yang baik. Akibatnya sifat mekanik polimer akan menurun.

Phosphorus-containing fire retardants
Banyak retardants api tipe ini yang dikonversi menjadi asam fosfat, yang akan mengeringkan polimer yang berada dalam kondisi terbakar dan membentuk char. Sebagai contoh fosfor oxynitride dan phospham pada 10-20% wt yang ditambahkan ke poli (butylene terephthalate) memberikan peningkatan indeks oksigen dari 22 menjadi 29. Oxynitride fosfor juga ditemukan sebagai pembentuk char. Pembentukan char mempengaruhi sifat tahan api bahan polimer karena bertindak sebagai penghalang yang akan memperlambat transfer panas, mencegah masuknya oksigen ke dalam polimer dan juga mencegah degradasi polimer. Senyawa yang meningkatkan pembentukan char, seperti oxynitride fosfor dan phospham, atau alkohol polifungsional, tepung dan turunan glukosa, telah menunjukkan sifat tahan api pada komposit polimer. Dalam beberapa kasus, fire retardant yang mengandung fosfor dapat berfungsi pada fase uap dengan menghasilkan radikal yang dapat memadamkan api.

Halogenated fire retardants
Untuk memahami mekanisme pemadaman api oleh senyawa terhalogenasi, maka harus diketahui dua reaksi berikut yang terjadi ketika polimer dengan fire retardant dibakar:
(1) RX --> R' + X" dimana X adalah CI atau Br
(2) X' + RH --> R' + HX
Pada dua reaksi di atas, RX adalah halogenated fire retardant dan RH adalah polymer. Dalam kondisi kebakaran, halogenated fire retardant akan menghasilkan radikal halogen dan halogen akan bereaksi dengan polimer untuk membentuk radikal baru dan HX. HX akan memadamkan api dengan bereaksi dengan hidroksil atau hidrogen yang dihasilkan selama dekomposisi polimer. Walaupun material ini dapat memberikan fire retardant yang baik pada loading rendah

The Cost of Cartilage Health: maintenance better than surgical repair?

Glucosamine and chondroitin are widely taken to help relieve knee pain from osteoarthritis but do they work?

The GAIT Study:

     Double blind
The study, like most good medical studies, was done ‘double blind’, that is neither the patients nor the people administering to them knew which treatment the patient was on.

     MORE cf link below
But when results of the group of patients with moderate to severe pain was analysed the investigators found that the combination of glucosamine and chondroitin sulphate WAS significantly effective for pain relief!
ie. a healthy dynamic life style may be pursued?
(This is true in my case - Add my experience to the study -Chondrosulf alone 400mg x 3 per day.)
The GUIDE finding Both glucosamine sulphate and acetaminophen were more effective in reducing pain than placebo. Patients taking glucosamine sulphate exhibited more relief than patients on acetaminophen.

It was concluded that once-daily 1500 mg oral doses of glucosamine sulphate may be the preferred treatment for knee osteoarthritis.

Note
It must be noted that unlike the GAIT study that was publicly funded the GUIDE study was sponsored by the manufacturers of the glucosamine compound that was used in the trial.


In both the GAIT and GUIDE studies 1500mg of glucosamine daily was used and in the GAIT study 1200mg of chondroitin daily was used. However, some manufacturers suggest that glucosamine and chondroitin sulphate supplements should be taken in two phases, for example -

* A loading phase of a month of increased levels of glucosamine (up to 2250mg) and 1200mg of chondroitin sulphate.

* A maintenance phase of 1500mg of glucosamine and 800mg of chondroitin sulphate.

Other suggestions are that glucosamine and chondroitin sulphate doses should be calculated based on a person’s body weight. One recommendation is 20mg of glucosamine for every 1kg of body weight, whilst another suggestion is as follows:

* If body weight is less than 54.5kg take 1,000mg glucosamine and 800mg chondroitin sulphate.
*
* If body weight is between 54.5 and 91kg take 1,500mg glucosamine and 1,200 mg chondroitin sulphate.
*
* If body weight is more than 91kg take 2,000mg glucosamine and 1,600mg chondroitin sulphate.
(sounds reasonably logical start point from a materials engineering stand point) Are these ploys by supplement companies to sell more of their product or is there a scientific basis for these recommendations? Well, at present the evidence for doses and schedules is fairly sparse and that is one of the reasons why daily doses of 1500mg of glucosamine and 1200mg of chondroitin sulphate are common recommendations.

What about the source of these products-QC-AC-TQM?

Chondroitin sulphate is usually produced from cow (bovine) cartilage but can be produced from pig (porcine), chicken and even shark cartilage. Glucosamine on the other hand is derived from shellfish, usually shrimp, lobster or crab shells.


An important and informative discussion followed cf link
en référence à :

"Other factors   Chondroitin sulphate production in the body can be hindered if there is a deficiency of some key vitamins and minerals, in particular manganese, vitamin C and vitamin A. As participants in the GAIT study didn’t appear to undergo a dietary analysis prior to the start of the trial it is possible that some individuals may have had deficiencies in these key substances."
- Cartilage Health - Glucosamine and Chondroitin Supplement (afficher sur Google Sidewiki)

COMMENT:

Although I have no information on the cost of "wide-spread full life-cycle cost of surgery, It would appear obvious to an industrial R&D person such as I that the low risk relatively easy to extend chemical route is the road to take and ought to be introduced before serious pain results. In my case knee pain was reaching the handicapping stage whereby X-Rat readily detected near absence of cartilage on one side of th knee joint. The chemical supplement has been working well for several years and I am sorry not to have discovered in a simple X-Ray check-up! Not only has knee pain practically totally disappeared improvement in back-pain and disc slip has also greatly improved by my Chondroitin suppliment intake

Materials Views_2010-05-28 reports superior hyper-duplex corrosion resistant stainless steel

Materials Views_2010-05-28 reports superior hyper-duplex corrosion resistance. "The Influence of microstructure on the corrosion resistance of a newly developed hyperduplex stainless steel has been studied by a team of Brazilian  Metallurgists; S. S. M. Tavares, J. M. Pardal, A. Loureiro , E. Ponzio,  J. A. de Souza from the Universidade Federal Fluminense -  (Brazil)"

"Hyperduplex UNS S32707 is a newly developed austenitic-ferritic (dual phase or duplex) stainless steel. The steel contains about 27%Cr, 7%Ni, 4.5%Mo, and 0.4%N, which results in a pitting resistance equivalent factor (PRE) equal to 49. In this study, the pitting corrosion resistance of this new grade of stainless steel was investigated by varying the microstructure using different thermal processes. The critical pitting temperature measurement and cyclic polarization tests confirm the high corrosion resistance of the hyperduplex steel in the solution treated condition. However, deleterious phases form easily during thermal processing and cause a drastic decrease in the corrosion resistance.

Jounal, Authors and ABSTRACT

Materials Views Summary

Materials Views' Martin Grolms gives the reader some some of the essentials:eg.
For ranking the pitting resistance equivalent (PRE) number is used. PRE is based on the chemical composition of the steel and can be calculated as following:

PRE=%Cr+3.3(%Mo+%W)+16(%N)).

Increasing some of the parameters, like in this case, the amounts of Cr and N, leads to the development of stainless steel with ultrahigh corrosion resistance - hyperduplex steel. It contains about 27%Cr, 7%Ni, 4.5%Mo, and 0.4%N, so that PRE is equal to 49.

Pitting potential at a fixed temperature and critical pitting temperature (CPT) both increase with the PRE value. For hyperduplex steel CPT values above 90 have been reported. However, precipitation of tertiary phases such as sigma (δ), chi (χ), and Cr2N often decreases the CPT.

At the Brazilian Fluminense Federal University (UFF) investigations were conducted to get a deeper insight into the microstructure and corrosion properties of the new hyperduplex stainless steel.

Experimental:

A tube of steel, with a diameter of 12.5 mm and thickness of 2 mm, was purchased under the solution treated condition. Small pieces of this tube were cut for the study.

One of the specimens represented the original hyperduplex tube, while the other ones were produced by six different thermal procedures.

Results-Microstructure:

Afterwards some specimens had unequal austenite/ferrite proportions, and other were δ-phase precipitated.

The experimental procedure and results are further summarised in Materials views

Findings:

The corrosion resistance of hyperduplex stainless steel is higher than the other austenitic–ferritic steels, since a CPT higher than 92°C was obtained. The Critical PRE values are approx. 45–55ºC for solution treated duplex steels and 80–90ºC for superduplex steels.

Applications:

“The first application of hyperduplex stainless steels seems to be as heat exchange tubes used in the petroleum platforms in Brazil”, says Sérgio S.M. Tavares from UFF. “The material has mechanical and corrosion resistance superior to superduplex steels, which makes it very attractive in the off-shore equipments. High Cr and Mo content makes it more susceptible to embrittlement phenomena associated to intermetallic precipitation. The challenge lies in the development of reliable welding procedures for the hyperduplex steel”.

“The first application of hyperduplex stainless steels seems to be as heat exchange tubes used in the petroleum platforms in Brazil”, says Sérgio S.M. Tavares from UFF. “The material has mechanical and corrosion resistance superior to superduplex steels, which makes it very attractive in the off-shore equipments. High Cr and Mo content makes it more susceptible to embrittlement phenomena associated to intermetallic precipitation. The challenge lies in the development of reliable welding procedures for the hyperduplex steel”.

References:

MaterialsViews with enlarged size micro-image.
Wiley Interscience

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It's not HSLA-Bainite"Nanostructured Steels"-Green Light by Irvine-based Materials Science Co-MMFX Tech Corp - Corrosion and Toughness Themes

Other References

Duplex Stainless Steels (Conference proceedings / American Society for Metals)Duplex Stainless Steels (Conference proceedings / American Society for Metals)

Advanced Material Coatings for High Strength, High Conductivity Substrates from Innocentive

Advanced Material Coatings for High Strength, High Conductivity Substrate



presented by INNOCENTIVE

The Seeker is looking for advanced materials (alloys, metal composites, advanced coatings, surface treatments, etc.) to be used as the contact surface of a high speed rail system. The conductive material must withstand thermal, mechanical and electrical cycling while still retaining surface hardness and strength properties.


This Challenge is an Ideation Challenge, which varies from traditional InnoCentive challenges in the following ways:

• There is a guaranteed award. The awards will be paid to the best submission(s), which are solely determined by the Seeker. The total payout will be $10,000. The Seeker can payout as one award or split it among the best submissions. One award will be at least $5,000 and no award will be less than $1,000.
• Your submission will identify and describe a material/process that meets the requirements of the Challenge. You are required to give the Seeker a free, perpetual, and non-exclusive license to use any information submitted for this Challenge.

The Seeker will complete the review process and make a decision after the Challenge deadline. All Solvers that provide a submission will be notified as to the status of their submission; however, there will not be any detailed evaluation of your submission given. 

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