Filtry
wszystkich: 2779
wybranych: 2478
-
Katalog
- Publikacje 2478 wyników po odfiltrowaniu
- Czasopisma 44 wyników po odfiltrowaniu
- Konferencje 1 wyników po odfiltrowaniu
- Osoby 51 wyników po odfiltrowaniu
- Wynalazki 5 wyników po odfiltrowaniu
- Projekty 2 wyników po odfiltrowaniu
- Zespoły Badawcze 1 wyników po odfiltrowaniu
- Kursy Online 48 wyników po odfiltrowaniu
- Wydarzenia 25 wyników po odfiltrowaniu
- Dane Badawcze 124 wyników po odfiltrowaniu
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: TAQ POLYMERASE
-
The Effect of Citric Acid on Physicochemical Properties of Hydrophilic Carboxymethyl Starch-Based Films
Publikacja -
An overview of developments in poly(urethane-isocyanurates) elastomers
PublikacjaNauka i technologia jest przede wszystkim ukierunkowana na rozwój nowych materiałów polimerowych z pożądanych właściwościach. Takimi materiałami są bez wątpienia poliuretany zawierające w swojej strukturze pierścienie izocyjanurowe, charakteryzują się wysoką odpornością termiczną. Wiele z nich jest wykorzystywana jako sztywne pianki w budownictwie. Coraz większym zainteresowaniem cieszą się elastomery uretanowo-izocyjanurowe.
-
Effect of starch fillers on the dynamic mechanical properties of rubber biocomposite materials
PublikacjaIn the paper the results of dynamic mechanical study of the biocomposites containing one of two types of (potato or corn) strach used as fillers in different amount were discussed. The composites were obtained from rubbery mixture containing natural rubber (NR) as a main component. Thermomechanical analyses (by DMA) showed that the used quantity of strach fillers only slightly influence on the glass transition temperature of vulcanizates.
-
Evaluation of the glycerolysis process and valorisation of recovered polyol in polyurethane synthesis
PublikacjaIn this study, the glycerolysis of polyurethane (PU) foam and the applicability of obtained glycerolysate (GLY) for cast PUs were investigated. It was found that crude glycerine with purity grade of 84% might be successfully used for the glycerolysis. The optimal conditions were determined as follows: reaction time of 60 min at 220 °C using dibutyltin dilaurate catalyst (0.5%). Moreover, the purification of GLY by means of liquid-liquid...
-
The Effect of Polyurethane Glycolysate on the Structure and Properties of Natural Rubber/Carbon Black Composites
PublikacjaIn this work the use of polyurethane chemical recycling product (i.e. glycolysis of polyurethane waste realized with the mass excess of polymer) as a plasticizer for natural rubber-based composites was proposed. The effect of plasticizer type (napthenic oil and polyurethane foam glycolysate) and amount (2, 4, 6 or 8 parts per 100 parts of natural rubber) on the processing properties of rubber mixtures and chemical structure, swelling,...
-
Studies on the Combined Impact of Starch Source and Multiple Processing on Selected Properties of Thermoplastic Starch/Ethylene-Vinyl Acetate Blends
PublikacjaThermoplastic starch (TPS)/ethylene vinyl acetate (EVA) blends compatibilized with polyethylene-graft-maleic anhydride (PE-g-MA) were prepared from various native starches (potato, maize and waxy maize) and subjected to multiple extrusion cycles. Source of starch has significant impact on its composition, hence properties of obtained TPS and their blends with EVA. Higher content of amylopectin in waxy maize starch, comparing to...
-
Investigation of Thermoplastic Polyurethanes Synthesized via Two Different Prepolymers
PublikacjaThe man aim of this work was to investigate the effect of the molecular weight of polyols, mixture of prepolymers, and [NCO]/[OH] molar ratio used during the prepolymer chain extending step on the chemical structure, thermomechanical and mechanical properties, and thermal stability of thermoplastic poly(ether-urethane)s In this work thermoplastic poly(ether-urethane)s were synthesized by using polyols with a various molecular weight,...
-
Structure-property relationships in peroxide-assisted blends of poly(ε-caprolactone) and poly(3-hydroxybutyrate)
PublikacjaPoly(ε-caprolactone) and poly(3-hydroxybutyrate) (PCL/PHB) blends in two weight ratios (75/25 and 50/50) were reactively compatibilized in the presence of di-(2-tert-butyl-peroxyisopropyl)-benzene and dicumyl peroxide as free radical initiators. Rheological, mechanical, thermal properties and morphological features, as well as the chemical structure of PCL/PHB blends were investigated. It was found that regardless of PCL/PHB blend...
-
Two-step Conversion of Crude Glycerol Generated by Biodiesel Production into Biopolyols: Synthesis, Structural and Physical Chemical Characterization
PublikacjaIn this work biopolyols were synthesized via two-step process from crude glycerol and castor oil. For better evaluation of analyzed process, the impact of its time and temperature on the structure and properties of biopolyols was determined. Obtained results fully justified conducting of synthesis in two steps. Prepared materials were characterized by hydroxyl value and water content comparable to polyols industrially applied in...
-
Injectable poloxamer/graphene oxide hydrogels with well‐controlled mechanical and rheological properties
PublikacjaAlthough significant progress has been made in the design and application of injectable hydrogels for biomedical applications, concurrent control of rheological and mechanical properties of injectable hydrogels has remained as an open challenge to the researchers. In this work, we introduce and put into practice a photo‐curable poloxamer (also known as Pluronic)/graphene oxide (Plu/GO) injectable hydrogel with well‐controlled rheological...
-
The Influence of Substitution of a Phosphorus-Containing Polyol with the Bio-polyol on the Properties of Bio-based PUR/PIR Foams
PublikacjaIn this work, effects of incorporating of a phosphorus-containing polyol into rigid polyurethane/polyisocyanurate foams’ formulations developed with use of two different bio-based polyols, derived from crude glycerol or liquefied cellulose were examined. The bio-polyol derived from crude glycerol was synthesized via two-step process from crude glycerol and castor oil, whereas the bio-polyol derived from liquefied cellulose was...
-
Structure, Mechanical, Thermal and Fire Behavior Assessments of Environmentally Friendly Crude Glycerol-Based Rigid Polyisocyanurate Foams
PublikacjaIn this work, rigid polyisocyanurate foams were prepared at partial substitution (0–70 wt%) of commercially available petrochemical polyol, with previously synthesized biopolyol based on crude glycerol and castor oil. Influence of the biopolyol content on morphology, chemical structure, static and dynamic mechanical properties, thermal insulation properties, thermal stability and flammability was investigated. Incorporation of...
-
Cast polyurethanes obtained from reactive recovered polyol intermediates via crude glycerine decomposition process
PublikacjaIn this work, the possibility of applying intermediates from polyurethane waste recycling in polyurethane synthesis was presented. Polyurethanes were synthesised in a two-step method using a mixture of petrochemical polyol and glycerolysate, used as a reactive component, 4,4-diphenylmethane diisocyanate (MDI) and 1,4-buthanediol (BD). Glycerolysates were produced during decomposition of polyurethane elastomer by crude glycerine...
-
A New Approach to Chemical Recycling of Polyamide 6.6 and Synthesis of Polyurethanes with Recovered Intermediates
PublikacjaA new efficient method for the chemical decomposition of polyamide 6.6 by the glycolysis and amino-glycolysis processes was proposed. The glycolysis was conducted using the mass excess of ethylene glycol (EG) as a decomposing agent in the presence of a catalyst. Also, a mixture of EG and triethylenetetramine was used as another decomposing agent in the amino- glycolysis process. The described process of decomposition did not...
-
Thermo-Chemical Decomposition Study of Polyurethane Elastomer Through Glycerolysis Route with Using Crude and Refined Glycerine as a Transesterification Agent
PublikacjaDue to the increasing amount of polyurethane waste, chemical recycling of these materials is a topic of growing interest for many researchers. The primary pur- pose of polyurethane feedstock recycling is to recover the starting polyol. In this study glycerolysis using glycerine from two sources and two purity grades is proposed as a method of chemical recycling. The main effort of this paper focuses on the employment of commercial...
-
Controlled grafting of vinylic monomers on polyolefins: a robust mathematical modeling approach
PublikacjaExperimental and mathematical modeling analyses were used for controlling melt free-radical grafting of vinylic monomers on polyolefins and, thereby, reducing the disturbance of undesired cross-linking of polyolefins. Response surface, desirability function, and artificial intelligence methodologies were blended to modeling/optimization of grafting reaction in terms of vinylic monomer content, peroxide initiator concentration,...
-
Degradation of polycaprolactone modified with TPS or CaCO3 in biotic/abiotic seawater
PublikacjaThis paper is an investigation of the polymer degradation process in two types of seawater (with and without microorganisms) sourced from the Baltic Sea. The chosen polymeric materials were polycaprolactone modified with either thermoplastic starch (PCL/TPS>85%) or calcium carbonate (60% PCL/40% CaCO3) compared directly against unmodified polycaprolactone. All samples were incubated for 28 weeks in seawater with and without microorganisms...
-
Degradation of Polycaptolactone Modified with TPS or CaCO3 in Biotic/Abiotic Sewater
PublikacjaThe polymer degradation process in two types of water sourced from the Baltic Sea was investigated. Polycaprolactone modified with thermoplastic starch(PCL/TPS>85%) or calcium carbonate (60% PCL/40% CaCO3)and PCL alone were incubated for 28 weeks in sea water with and without microrganisms. The experimental results indicated that in each of the experiments degradation occured. The process was more effective in sea water with microorganisms.Modification...
-
Proposal of New Starch-Blends Composition Quickly Degradable in Marine Environment
PublikacjaThe aim of this paper was to obtain a quickly degradable in seawater polymer blend as an alternative proposal for classical polymer packaging. For preliminary studies: poly(lactic acid) (PLA), starch, calcium carbonate (CaCO3), gelatin and glycerol were chosen. PLA was pointed out due to its biodegradability and comparable properties to polyethylene or polypropylene. Whereas starch was chosen as abundant, renewable and cheap polymer...
-
l-ascorbic acid modified poly(ester urethane)s as a suitable candidates for soft tissue engineering applications
PublikacjaIn this paper we created novel poly(ester urethane)s (PESUs) designed specifically for tissue engineering. The PESUs were derived from oligomeric α,ω-dihydroxy(ethylene-butylene adipate) (dHEBA), 1,4-butanediol (BDO) and aliphatic 1,6-hexamethylene diisocyanate (HDI) and modified with l-ascorbic acid to improve their biocompatibility. In addition, we determined their mechanical properties (such as tensile strength, elongation at...
-
A novel method for drop in drop edible oils encapsulation with chitosan using a coaxial technique
PublikacjaThe presented work concerns a novel one step method for oil encapsulation. In this coaxial system the oil constitutes the core of the capsule, while the chitosan solution is the polymer shell surrounding the core to provide separation of the core from the external environment. The paper contains a diagram of the encapsulation equipment and explains the principle of its operation. The experimental results showed the impact of the...
-
Eco-friendly Route for Thermoplastic Polyurethane Elastomers with Bio-based Hard Segments Composed of Bio-glycol and Mixtures of Aromatic–Aliphatic and Aliphatic–Aliphatic Diisocyanate
PublikacjaApplication of bio-based diisocyanates with low volatility instead petrochemical diisocyanates has positive impact on environment by reduction of hazardous effects on living organisms and lead to bio-based polyurethanes (bio-PUs) with good usage properties. This work was focused on the synthesis and chosen properties examination of partially bio-based thermoplastic polyurethane elastomers (bio-PUs) obtained using diisocyanate mixtures,...
-
Preparation and Characterization of Films Based on Disintegrated Bacterial Cellulose and Montmorillonite
PublikacjaThe food packaging materials from natural polymers including polysaccharides offer an ecologically important alternative to commonly used synthetic, non-biodegradable counterparts. The purpose of this work was to modify of bacterial cellulose (BC) leading to the improvement of its functional properties in terms of use as a food packaging material. Effects of disintegration of BC and addition of montmorillonite (MMT) on its water...
-
Submicron inorganic particles as an additional filler in hybrid epoxy matrix composites reinforced with glass fibres
PublikacjaIn this study, the effect of selected submicron metal oxide (zinc oxide, titanium oxide) or non-metal oxide (silicon dioxide) particles on mechanical and thermo-mechanical properties of epoxy/glass composites was investigated. The applied epoxy resin was a diglycidyl ether of bisphenol-A cured with triethylenetetramine. As a reinforcement twill weave E-glass fabric was used. Hybrid composites (contained particulate and fibrous...
-
Layer-by-layer polymer deposited fabrics with superior flame retardancy and electrical conductivity
PublikacjaSmart and multifunctional textiles and fabrics are progressively developing, such that multifunctional fabrics are becoming more widespread. We elaborated herein multi-layered flax fabrics with superior flame retardancy and conductivity, which revealed fireproof feature while keeping conductivity during burning. The flax fabric was reinforced by layer-by-layer (LbL) deposition of sodium polyacrylate (SPA), polyethylenimine (PEI),...
-
Structural evaluation of percolating, self-healing polyurethane–polycaprolactone blends doped with metallic, ferromagnetic, and modified graphene fillers
PublikacjaComposites with differently shaped micro- and nanofillers show various, unique thermal, and physicochemical properties when mixed with carefully chosen polymer matrix. Selected composition holds strategic value in achieving desired properties that is biodegradability, thermoelectric conductivity, and shape memory for organic coating. The main aim of this work is to briefly examine structural changes after reaching percolation threshold...
-
The Taste of Waste: The Edge of Eggshell Over Calcium Carbonate in Acrylonitrile Butadiene Rubber
PublikacjaRubber technology experiences a new age by the use of biowaste or natural fillers. In this regard, taking properties of reinforcing agents from biowaste fillers remains as the challenging matter. Chicken eggshell (ES) biowaste has recently been introduced to substitute calcium carbonate (CaCO3) duo to its superior properties and low price. In this work, composites based on acrylonitrile butadiene rubber (NBR) reinforced with ES...
-
The study on application of biopolyols obtained by cellulose biomass liquefaction performed with crude glycerol for the synthesis of rigid polyurethane foams
PublikacjaIn this work rigid polyurethane foams (PUR) were obtained by replacement of 0–70 wt% of petrochemical polyol with bio-polyol obtained via cellulose liquefaction in presence of crude glycerol. The foams with different content of a bio-polyol were prepared by single step method for NCO/OH ratio equals 1.5. The prepared materials were analyzed in terms of their morphology, chemical structure, thermal stability and basic physical and...
-
The effect of high molecular weight bio-based diamine derivative of dimerized fatty acids obtained from vegetable oils on the structure, morphology and selected properties of poly(ether-urethane-urea)s
PublikacjaIn this work, the effect of the high molecular weight bio-based diamine on the chemical structure and selected properties of poly(ether-urethane-urea)s has been investigated. The ether-urethane prepolymer was cured using 1,4-butanediol and/or bio-based diamine. Mentioned chain extenders were used separately or in the mixture, and their different molecular weight and chemical structure resulted in obtaining materials with diversified...
-
Bioactive and bioavailability of minerals in rats loaded with cholesterol and kiwi fruit
PublikacjaThe aim of this study was to compare the content of polyphenols (TP), minerals, ascorbic acid (AA) and total antioxidant capacities (TAC) of conventional and organic kiwifruit ‘Hayward’ treated with ethylene after harvest and to determine their influence on plasma TAC, mineral content in the liver and bioavailability (RBV — relative bioavailability value) in rats fed diet containing cholesterol. Organic and conventionally grown...
-
It is not OK but it works – unproductive entrepreneurship, the case of Poland
PublikacjaThe concept of unproductive entrepreneurs was introduced to science by Baumol, who pointed out the differences in business output between countries. Unproductive behaviour of entrepreneurs is often a consequence of ineffective institutions used by entrepreneurs for rent seeking. The aim of this article is to examine subjective norms (S.N.) and attitudes regarding specified types of unproductive entrepreneurship, which in many cases...
-
Uwarunkowania polityczne rozwoju regionalnego w Polsce na przykładzie województwa pomorskiego
PublikacjaTreść opracowania dotyczy decyzji i zachowań politycznych w kwestiach rozwoju regionalnego w Polsce, tak na poziomie władzy centralnej, jak i wojewódzkiej.
-
Założenia i cele projektu ZEUS
PublikacjaWstępnym celem projektu jest integracja działań na rzecz budowy systemu bezpieczeństwa w transporcie tak, aby jego funkcjonowanie nie było efektem doraźnych realcji społeczeństwa na pojedyncze katastrofy, lecz metodycznym działaniem, zapewnionym prawem ustanowionym na baziw solidnych i dobrze udokumentowanych działań naukowych. Głownym celem projektu jest opracowanie modelu zintegrowanego systemu bezpieczeństwa transportu, tak...
-
Entropy Production Associated with Aggregation into Granules in a Subdiffusive Environment
PublikacjaWe study the entropy production that is associated with the growing or shrinking of a small granule in, for instance, a colloidal suspension or in an aggregating polymer chain. A granule will fluctuate in size when the energy of binding is comparable to k_{B}T, which is the “quantum” of Brownian energy. Especially for polymers, the conformational energy landscape is often rough and has been commonly modeled as being self-similar...
-
Superconducting SrSnP with Strong Sn–P Antibonding Interaction: Is the Sn Atom Single or Mixed Valent?
PublikacjaThe large single crystals of SrSnP were prepared using Sn self-flux method. The superconductivity in the tetragonal SrSnP is observed with the critical temperature of ∼2.3 K. The results of a crystallographic analysis, superconducting characterization, and theoretical assessment of tetragonal SrSnP are presented. The SrSnP crystallizes in the CaGaN structure type with space group P4/nmm (S.G. 129, Pearson symbol tP6) according...
-
Properties of Windows Extracted from Fractional Delay Filters Optimal in Chebyshev Sense
PublikacjaJedną z najefektywniejszych numerycznie metod projektowania filtrów cyfrowych jest metoda okien. Jednak prostota tego podejścia wiąże się z reguły z niską jakością tak projektowanych filtrów, przede wszystkim ze względu na problemy z doborem odpowiedniego okna. Z tego powodu w zastosowaniach wymagających ciągłej aktualizacji współczynników filtrów, tak jak ma to miejsce w przypadku filtrów ułamkowo-opóźniających o zmiennym opóźnieniu,...
-
Pomiary w procesie budowy kadłuba statku
PublikacjaStatki i obiekty oceanotechniczne to największe ruchome ruchome dzieła sztuki inżynierskiej. Budowie takich kolosów towarzyszą procesy pomiarowe – nierzadko na odległości przekraczające kilkaset metrów i dokładnościach milimetrowych. Tak było kilkaset lat temu i tak jest dzisiaj. Pomimo niezmienności praw fizyki i zasad geometrii przestrzennej, w metrologii okrętowej – tak jak w innych dziedzinach życia – zachodzą zmiany. Pojawienie...
-
O imionach bogów
PublikacjaArtykuł omawia i analizuje Cassirerowską koncepcję imion bogów. Koncepcja ta pochodzi z najważniejszego bodaj okresu jego twórczości – okresu współpracy z Biblioteką Warburga – i mimo niewielkich rozmiarów jest w dużej mierze reprezentatywna, tak gdy idzie o wykorzystywaną przez niego metodę, jak i o główny obszar jego zainteresowań badawczych. Stanowi bezpośrednie nawiązanie do rozprawy Hermanna Usenera Götternamen. Versuch einer...
-
Real-time isothermal DNA amplification monitoring in picoliter volumes using an optical fiber sensor
PublikacjaRolling circle amplification (RCA) of DNA can be considered as a great alternative to the gold standard polymerase chain reaction (PCR), especially during this pandemic period, where rapid, sensitive, and reliable test results for hundreds of thousands of samples are required daily. This work presents the first research to date on direct, real-time and label-free isothermal DNA amplification monitoring using a microcavity in-line...
-
Czy chemia wszechświata różni się od chemii na planecie Ziemia?
PublikacjaAstronomowie, fizycy i chemicy od lat zadają sobie pytanie na ile nasza planeta jest wyjątkowa. Żyjemy na jednym z nielicznych ciał niebieskich, na którym występuje woda w stanie ciekłym. Na naszej planecie pojawiła się niezwykle szeroka gama prostych i wyjątkowo skomplikowanych związków organicznych. Warto jednak zadać pytanie czy faktycznie ziemia jest tak wyjątkowa pod kątem chemicznym, a jeśli tak to co na to wpływa. Współcześnie...
-
Elastic electron scattering by argon in the vicinity of the high-energy critical minimum.
PublikacjaZostały obliczone różniczkowe przekroje czynne na sprężyste rozpraszanie elektronów na argonie. Przedział energetyczny rozpraszanych elektronów został tak dobrany, aby zbadać położenie tzw. minimum krytycznego.
-
Structural Variety of Cobalt(II), Nickel(II), Zinc(II), and Cadmium(II) Complexes with 4,4′-Azopyridine: Synthesis, Structure and Luminescence Properties
PublikacjaSelf-assembled bi- and polymetallic complexes of CoII, NiII, ZnII, and CdII were obtained by the reaction of 4,4′-azopyridine (azpy) with metal tri-tert-butoxysilanethiolates (Co, 1; Cd, 2), acetylacetonates (Ni, 3; Zn, 4), and acetates (Cd, 5). All compounds were characterized by single-crystal X-ray structure analysis, elemental analysis, FTIR spectroscopy, and thermogravimetry. Complexes 1, 2 and 4, 5 exhibit diverse structural...
-
Synchronizacja pomiarów z drezyny EM-120 w planowaniu napraw
PublikacjaW artykule zaprezentowano metodykę synchronizacji pomierzonych nierówności geometrycznych w różnych przedziałach czasowych. Tak opracowane pomiary umożliwiły dokonanie analizy trendu deformacji toru na kilku liniach kolejowych.
-
Pierwiastek, nie całkiem z piekła rodem - cz. I
PublikacjaW ramach doniesienia zaprezentowano ciekawe, intrygujące choć niekiedy zupełnie nieznane dane dotyczące siarki. Pierwiastek o tak olbrzymim znaczeniu ekonomicznym jest bowiem także nadzwyczajinteresującym problemem chemicznym.
-
Synthesis and biological activity of novel mycophenolic acid conjugates containing nitro-acridine/acridone derivatives
PublikacjaOpracowano warunki reakcji kwasu mykofenolowego z aminowymi pochodnymi akrydyn i akrydonów. Tak otrzymane koniugaty zostały scharakteryzowane, a następnie przebadane in vitro pod względem aktywności przeciwbiałaczkowej oraz immunosupresyjnej.
-
Quantitative interpretation of energy-based systems and index of their reliability
PublikacjaW artykule zaproponowano interpretację wartościującą działania, które rozumiane jest jako wielkość fizyczna o jednostce miary zwanej dżulosekundą. Przedstawiono oryginalną metodę analizy i oceny tak rozumianego działania dowolnego systemu energetycznego z uwzględnieniem jego niezawodności i bezpieczeństwa. Do uzasadnienia przydatności tak interpretowanego działania zastosowano jednorodny proces Poissona. Proces ten umożliwił skonstruowanie...
-
Kładka łukowa przez Wartę we Wronkach : Projekt i realizacja.
PublikacjaW referacie przedstawiono historię projektowania i realizacji nietypowej kładki z przęsłem łukowym o rozpiętości 90 m. Pierwotny zamysł architektoniczny został zrealizowany dzięki opracowaniu nowego projektu konstrukcyjnego. W fazie projektowania skoncentrowano się na ukształtowaniu konstrukcji tak, aby zoptymalizować zużycie stali i nakłady na fundamenty. Istotnym elementem projektu było dobranie charakterystyk dynamicznych tak,...
-
Enhancing Security of Advanced Metering Infrastructure by Introducing Threshold Attendance Protocol
PublikacjaThe industry pushes towards smart grid systems in order to resolve current limitations of the unidirectional legacy power grid infrastructure. By introducing Advanced Metering Infrastructure (AMI) as an integral part of the smart grid solution, the utility company obtains an invaluable tool to optimize its network, lower the operational costs, and improve quality of service. Unfortunately, introducing two-way communication poses...
-
The Impact of Lightning Flashes and Sprites on the Earth’s Global Electric Circuit: An Overview of Recent Modeling Results
Publikacja -
The σ-phase superconductors Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9
PublikacjaWe show that the previously unreported ternary σ phases Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are both superconductors with Tc values of approximately 1.9 K. The superconducting transitions were characterized through temperature-dependent magnetic susceptibility, electrical resistance, and specific heat measurements. The Sommerfeld constants, γ, for Nb20.4Rh5.7Ge3.9 and Nb20.4Rh5.7Si3.9 are 89(1) mJ mol-f.u.−1K−2 and 86(1) mJ mol-f.u.−1K−2...