In presented work, raw, expanded and acid treated vermiculites were used as low-cost and active adsorbents for reducing of environmental pollution with heavy metals. Acid treatment was performed at elevated temperature (95°C) for 2 and 24 h in solution of HNO3. Adsorption capacity towards Fe3+ was studied in column, semi-batch and batch mode. It was shown that all samples are effective in removal of heavy metals; however adsorption mechanism is based not only on ion exchange of interlayer cations but also precipitation/deposition processes. Starting material and modified samples as well as spent adsorbents were characterized with respect to the vermiculite structure using X-ray diffraction method., Agnieszka Węgrzyn, Lucjan Chmielarz, Paweł Zjeżdżalka, Andrzej Kowalczyk, Magdalena Jabłońska, Xavier Baldrich Tolosa and Marek Michalik., and Obsahuje bibliografii
Adsorption of phenol and aniline onto original and with quaternary ammonium salts (QASs)-modified montmorillonite was described by sorption isotherms of type III and II, respectively. For the montmorillonite (MMT) modification - hydrophobisation, cetyltrimethyl- ammonium (CTMA) and tetramethylammonium (TMA ) cations were used. In comparison with phenol, aniline was adsorbed largely on original MMT but less on modified one. XRD pa tterns indicated that both aromatic compounds were intercalated in the MMT interlayer be ing perpendicularly oriented to silicate sheets. Alkyl chains of CTMA and TMA probably act as organic "pillars" stabilising the MMT tabular structure against exfoliation due to the intercalation with phenol and aniline of high concentrations., Hana Kostelníková, Petr Praus and Martina Turicová., and Obsahuje bibliografické odkazy
LDL-aferéza je extrakorporální eliminační metodika, která usiluje o pokud možno specifické odstranění LDL-cholesterolu z cirkulující krve. V současnosti je používáno 6 účinných metod k selektivnímu odstranění LDL-cholesterolu. Mezi hlavní indikace k léčbě LDL-aferézou patří diagnózy homozygotní familiární hypercholesterolemie, heterozygotní familiární hypercholesterolemie refrakterní nebo při intoleranci k standardní léčbě, a dále pacienti se zvýšením lipoproteinu(a) refrakterní nebo intolerantní k farmakoterapii. Dosud však není jednoty o tom, jaká hladina LDL-cholesterolu je rozhodující pro zahájení LDL-aferézy, názory se liší i v jednotlivých státech. I když neexistují klasické velké randomizované studie, existuje dostatečný počet dobře řízených studií k tomu, aby v celém světě bylo uznáváno, že je efekt LDL-aferézy na kardiovaskulární prognózu u závažné hypercholesterolemie významný., LDL-apheresis is an extracorporeal elimination technique, which specifically removes LDL-cholesterol from the circulation. There are six methods for the selective LDL-cholesterol removal these days. The main indications for LDL-apheresis are the diagnosis of homozygous familial hypercholesterolemia, heterozygous familial hypercholesterolemia which is refractory the standard care and intolerance of routine care, and also patients with lipoprotein(a) increase resistant to the farmacotherapy. There is still debate which LDL-cholesterolemia is indication for LDL-apheresis therapy, and the recommendation differs among various countries. Despite large randomized trials are missing, there are several good quality studies to conclude, that the beneficial cardiovascular effects of LDL-apheresis in severe hypercholesterolemia are important and beneficial, and Vladimír Bláha, Milan Bláha, Miriam Lánská, Eduard Havel, Pavel Vyroubal, Zdeněk Zadák, Pavel Žák, Luboš Sobotka
Arsenic, antimony and selenium belong to toxic contaminants with high environmental risk. In contrast to metal cationic contaminants (Be, Zn, Cd, Hg Pb, etc.) the metalloids and nonmetals of groups 5 and 6 of periodic system generally form the oxyanions in two oxidizing states (i.e. arsenates and arsenites, antimonates and antimonites, as well as selenates and selenites) in dependence on redox potential and pH value. It is well known that above mentioned oxyanions have a strong adsorption affinity to hydrated oxides and/or oxides hydroxides of Fe, Al and Mn, preferably Fe forming stable surface complexes. In fact, commercially produced Fe oxides-based sorbents are too expensive for strongly contaminated aqueous systems. Aluminosilicates have opened new possibilities in sorption technology due to favourable surface properties, availability, environmental and economical reasons, but they are not selective sorbents of anionic contaminants thanks to a low pHZPC. A simple Fe/Al/Mn pre-treatment of raw aluminosilicates can significantly improve their sorption affinity to oxyanionic contaminants, including arsenites and arsenates, selenites and selenates and antimonites and antimonates, respectively. Different types of natural and/or second-rate clays (metakaolines with the large content of Fe, raw bentonites and natural clinoptilolite-rich tuff, ) from Central European localities were used for FeII, FeIII, AlIII and MnII pre-treatment., Barbora Doušová, Lucie Fuitová, Lenka Herzogová, Tomáš Grygar, David Koloušek and Vladimír Machovič., and Obsahuje bibliografii
Na titanovém povrchu tvoří fibrinogen silněji adsorbovanou vrstvu s vyšší hustotou uspořádání v porovnání s porézní a slabě adsorbovanou vrstvou albuminu. Fibrinogen se lépe adsorbuje na povrch titanu upravený leštěním a leptáním nežli na povrch pouze leštěný. K silné adsorpci fibrinogenu dochází na povrchu titanu obohaceném v určitém poměru uhlíkem. Nejlépe se fibrinogen adsorboval na povrchu titanu pokrytém uhlovodíkovou vrstvou se složením Ti0,36 - C0,57 : H0,07 a Ti0,08 - C0,68 : H0,24. Takto upravený povrch titanu by tedy splňoval podmínky pro nejlepší oseointegraci. Adsorpce fibrinogenu na titanovou slitinu Ti6Al4V byla slabá, naopak silná byla na slitině TiNbTa, která má také dobré mechanické vlastnosti, pokud jde o výrobu implantátů. homopyrimidinové oligodeoxynukleotidy (ODN) tvoří na povrchu titanu robustnější vrstvy s vyšší hustotou v porovnání se stejně dlouhými homopurinovými ODN a velice porézními vrstvami dvoušroubovicových fragmentů DNA., Fibrinogen is absorded at the titanium surface more firmly and with higher density contrary to a weakly adsorbed and porous albumin layer. Fibrinogen is better absorbed at the titanium surface treated by polishing and etching than at the surface treated only by polishing. Fibrinogen is strongly adsorbed at the titanium layer enriched by carbon to a certain ratio. The best adsorption of fibrinogen was observed at the titanium surface enriched with carbon at the ratio Ti0,36 - C0,57 : H0,07 a Ti0,08 - C0,68 : H0,24. The titanium surface treated in this way should fulfill the conditions for the best oseointegration. Adsorption of fibrinogen at the titanium alloy T6Al4V was weak contrary to the good adsorption at the TiNbTa alloy, which also has good mechanical properties concerning implant production. Homopyrimidine oligodeosynucleotides (ODN) form at the titanium surface more robust layers with higher density contrary to the homopurine ODN molecules of the same length and very porous layers of double stranded DNA fragments., Vladimír Vetterl, Stanislav Hasoň, Raimo Silvennoinen, Ladislav Cvrček, Luděk Strašák, Lukáš Fojt., and Obsahuje bibliografii
Adsorption procedure of two cationic surfactants hexadecyltrimethylammonium bromide (HDTMABr) and benzyldimethylhexadecylammonium chloride (BDHDACl) onto two samples of montmorillonite was studied. Infrared spectroscopy and X-ray diffraction proved intercalation of both quaternary cations into the interlayer space of montmorillonite. An aspect of time showed not to be important for the cations adsorption., Zuzana Navrátilová, Petr Wojtowicz, Lenka Vaculíková and Věra Šugárková., and Obsahuje bibliografické odkazy
Theoretical basics of thermal desorption spectroscopy and its realization in the Surfaces and Thin Films Laboratory is presented. As an example of application of this method a study of contamination of Si wafer is reported. and V článku jsou prezentovány teoretické základy termální desorpční spektroskopie a její aplikace ve výzkumu povrchů a tenkých vrstev. Jako příklad použití metody je uvedena studie kontaminace Si desek.