Silane surface treatment of polymers

Silani su silicijevi spojevi koji se koriste za obradu raznih površina jer zbog svoje specifiĉne strukture mogu reagirati s anorganskim supstratima ili sami sa sobom. Silani se pomoću reakcija hidrolize i kondenzacije veţu na tretirane površine. Silanska sredstva za vezivanje omogućuju modifikaciju hidrofobnih ili hidrofilnih svojstava površina. Hidrofobnost i hidrofilnost se određuje mjerenjem kontaktnog kuta kapljice vode s površinom, ako je kontaktni kut (θ) veći od 90° površina je hidrofobna, a ako je manji od 90° površina je hidrofilna. Silanska sredstva za vezivanje koriste za u mnogim primjenama, a njihova osnova uloga je poboljšanje svojstava krajnjeg proizvoda. Cilj ovoga rada bio je ispitati utjecaj pojedinih silana na površinska svojstva stakla i polimera. Uzorcima stakla, PE-HD, PE-LD, PLA, ABS umakanjem u Evonikove silane Dynasylan SIVO 121, Dynasylan SIVO 160, Dynasylan SIVO 214, Dynasylan SIVO CLEAR K2, Dynasylan DAMO, Dynasylan 40, Dynasylan 6598, Dynasylan 6490, Dynasylan 6498 promijenjena su površinska svojstva. Na pripremljenim uzorcima mjereni su kontaktni kutovi te je određeno je li površina hidrofobna ili hidrofilna. Na temelju provednog ispitivanja zaključeno je da se pomoću navedenih silana mogu modificirati površinska svojstva stakla i polimera.Silanes are silicon based compounds used for the treatment of various surfaces. Because of their specific structure they can react with inorganic substrates or between themselves. By the reactions of hydrolysis and condensation silanes bind to the treated surface. Silane coupling agents allow the modification of hydrophobic or hydrophilic properties of surfaces. Hydrophilicity is determined by measuring the contact angle of water droplets on the substrate surface, if the contact angle (θ) is greater than 90° the surface is hydrophobic, but if it is smaller than 90° the surface is hydrophilic. Silane coupling agents are used for many applications, but their base role is to improve the properties of the end product. The aim of this study was to investigate the influence of certain silanes on the surface properties of glass and polymers. Samples of glass, PE-HD, PE-LD, PLA, ABS were dipped in Evonik silanes Dynasylan SIVO 121, Dynasylan SIVO 160, Dynasylan SIVO 214, Dynasylan SIVO CLEAR K2, Dynasylan DAMO, Dynasylan 40, Dynasylan 6598, Dynasylan 6490, Dynasylan 6498 and their surface properties were modified. Contact angles were measured on the prepared samples. After completing the experiment, it was concluded that by using this silanes surface properties of glass and polymers can be modified

Forests of the Slavonian Military Frontier in the 18th Century

U radu se iz ekohistorijske perspektive prikazuju šume Slavonske vojne krajine u 18. stoljeću. Šume se proučavaju kao zasebni ekosistem te kroz njihovu interakciju s čovjekom. Rad se temelji na pregledu izvora – karti Slavonske vojne krajine iz 1780. godine, Šumskih uredbi iz 1787. godine i putopisu austrijskog državnog službenika Friedricha Wilhelma von Taubea. Naglasak je na prikazu izgleda šuma i njihovih karakteristika te na utjecaju čovjeka kroz ekonomsku eksploataciju i deforestaciju. Predstavljaju se oprečni pogledi vojne vlasti i krajišnika po pitanju korištenja i zaštite šuma.The paper portrays the forests of the Slavonian Military Border in the 18th century from the perspective of ecohistory. The forests are studied as a separate ecosystem and through their interaction with humans. The paper is based on an overview of sources – a map of the Slavonian Military Border from the year 1780, the Forest Decree from the year 1787 and the travelogue of the Austrian civil servant Friedrich Wilhelm von Taube. The paper emphasizes the appearance of forests and their characteristics, as well as man’s influence on forests through economic exploitation and deforestation. The conflicting views of the military authorities and the frontier soldiers on the use and protection of forests are presented

Silane surface treatment of polymers

Silani su silicijevi spojevi koji se koriste za obradu raznih površina jer zbog svoje specifiĉne strukture mogu reagirati s anorganskim supstratima ili sami sa sobom. Silani se pomoću reakcija hidrolize i kondenzacije veţu na tretirane površine. Silanska sredstva za vezivanje omogućuju modifikaciju hidrofobnih ili hidrofilnih svojstava površina. Hidrofobnost i hidrofilnost se određuje mjerenjem kontaktnog kuta kapljice vode s površinom, ako je kontaktni kut (θ) veći od 90° površina je hidrofobna, a ako je manji od 90° površina je hidrofilna. Silanska sredstva za vezivanje koriste za u mnogim primjenama, a njihova osnova uloga je poboljšanje svojstava krajnjeg proizvoda. Cilj ovoga rada bio je ispitati utjecaj pojedinih silana na površinska svojstva stakla i polimera. Uzorcima stakla, PE-HD, PE-LD, PLA, ABS umakanjem u Evonikove silane Dynasylan SIVO 121, Dynasylan SIVO 160, Dynasylan SIVO 214, Dynasylan SIVO CLEAR K2, Dynasylan DAMO, Dynasylan 40, Dynasylan 6598, Dynasylan 6490, Dynasylan 6498 promijenjena su površinska svojstva. Na pripremljenim uzorcima mjereni su kontaktni kutovi te je određeno je li površina hidrofobna ili hidrofilna. Na temelju provednog ispitivanja zaključeno je da se pomoću navedenih silana mogu modificirati površinska svojstva stakla i polimera.Silanes are silicon based compounds used for the treatment of various surfaces. Because of their specific structure they can react with inorganic substrates or between themselves. By the reactions of hydrolysis and condensation silanes bind to the treated surface. Silane coupling agents allow the modification of hydrophobic or hydrophilic properties of surfaces. Hydrophilicity is determined by measuring the contact angle of water droplets on the substrate surface, if the contact angle (θ) is greater than 90° the surface is hydrophobic, but if it is smaller than 90° the surface is hydrophilic. Silane coupling agents are used for many applications, but their base role is to improve the properties of the end product. The aim of this study was to investigate the influence of certain silanes on the surface properties of glass and polymers. Samples of glass, PE-HD, PE-LD, PLA, ABS were dipped in Evonik silanes Dynasylan SIVO 121, Dynasylan SIVO 160, Dynasylan SIVO 214, Dynasylan SIVO CLEAR K2, Dynasylan DAMO, Dynasylan 40, Dynasylan 6598, Dynasylan 6490, Dynasylan 6498 and their surface properties were modified. Contact angles were measured on the prepared samples. After completing the experiment, it was concluded that by using this silanes surface properties of glass and polymers can be modified

Varaždin’s Trade at the End of the 17th Century According to Gradski računi

U članku se obrađuje varaždinska trgovina krajem 17. stoljeća. Istraživanje se temelji na analizi dvaju dokumenta iz Državnog arhiva u Varaždinu. Radi se o računima gradskih primitaka i izdataka za 1688. i 1691. godinu. Kvantitativnom metodom nastoji se preispitati održivost teze o značajnosti varaždinske trgovine u regionalnom kontekstu na kraju 17. stoljeća. S obzirom na robu koja cirkulira na gradskim sajmovima i tržnici, naglasak je na prikazu više vrsta trgovina koje se prema njoj određuju. Donose se podaci o količini, pravcima uvoza i izvoza robe te o njezinoj vrijednosti prema iznosu poreza. Prikazuju se i kategoriziraju trgovci prema vrsti trgovine u kojoj sudjeluju.The paper deals with Varaždin’s trade at the end of the 17th century. The research is based on the analysis of two documents from the State Archives in Varaždin: the accounts of the town’s income and expenditures for 1688 and 1691. Using the quantitative method, the author seeks to re-examine the viability of the thesis of the importance of Varaždin’s trade in the regional context at the end of the 17th century. Several types of commerce are emphasized and these are selected with regard to the goods circulating at the town fairs and market. Data on the quantity, directions of import and export of goods and their value according to the amount of tax, are provided. Merchants are portrayed and categorized according to the type of trade in which they participate

The strophomenide brachiopod Ahtiella Öpik in the Ordovician of Gondwana and the early history of the plectambonitoids

The Precordilleran species Ahtiella Argentina Benedetto and Herrera, 1986 is redescribed and illustrated and Monorthis coloradoensis Benedetto, 1998b from northwestern Argentina is reassigned to the genus Ahtiella Öpik, 1932. Ahtiella famatiniana new species from volcaniclastic rocks of the Famatina range (western Argentina) and Ahtiella tunaensis new species from the Precordillera basin (Cuyania terrane) are proposed. Paleogeographic and stratigraphic evidence strongly suggests that Ahtiella originated in the Andean region of Gondwana to further migrate to Avalonia, Baltica, and Cuyania. Contrary to previous assumptions, the fossil record from the Famatina volcaniclastic succession suggests that the plectambonitoid Ahtiella famatiniana n. sp. evolved from the hesperonomiid orthoid Monorthis transversa Benedetto, 2003 that always occurs in the underlying strata. Phylogenetic analysis of Ahtiella species shows that A. famatiniana n. sp. and the Peruvian A. zarelae Villas in Gutiérrez-Marco and Villas, 2007 are not only the earliest species of the genus but also are morphologically intermediate between Monorthis Bates, 1968 and the later and more derived species of Ahtiella from Baltica and Cuyania. If, as empirical evidence presented here shows, Ahtiella originated from Monorthis through a series of minor transformations, then the impressive morphological gap between orthides and strophomenides was bridged through short-time cladogenesis events, suggesting that it might not have a definite discontinuity between the species level evolution and the origin of higher taxa (macroevolution).Fil: Benedetto, Juan Luis Arnaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; Argentin

Architecture of 5G networks and their applicability

Suvremena komunikacija i tehnologija nezamislive su bez mobilnih mreža. S porastom pametnih uređaja, potreba za bržim i pouzdanijim mrežama postala je ključna. U tom kontekstu, 5G mreža, kao nova generacija mobilnih mreža, donosi izvanredne performanse, uključujući visoke brzine prijenosa podataka, ultra nisku latenciju i sposobnost povezivanja velikog broja uređaja. U radu se istražuju karakteristike mobilnih mreža, definiraju se tehnički aspekti i prati se razvoj mobilnih mreža od prve do pete generacije. Također detaljno se analiziraju elementi arhitekture 5G mreže i istražuju tehničke karakteristike njezina rada. Opisane su tehnologije i usluge koje se primjenjuju u 5G mreži, uključujući virtualnu stvarnost, proširenu stvarnost, masivan prijenos sadržaja, Internet stvari i umjetnu inteligenciju. U rad se također istražuju primjene 5G mreže u industriji i prometu kroz primjere pametnih industrijskih pogona i modernih prometnih sustava povezanih na 5G mrežu.Contemporary communication and technology are inconceivable without mobile networks. With the proliferation of smart devices, the need for faster and more reliable networks has become paramount. In this context, the 5G network, as the new generation of mobile networks, delivers outstanding performance, including high data transfer speeds, ultra-low latency, and the capability to connect a large number of devices. The paper explores the characteristics of mobile networks, defines technical aspects, and traces the development of mobile networks from the first to the fifth generation. Furthermore, it thoroughly analyzes the elements of the 5G network architecture and investigates the technical features of its operation. Technologies and services applied in the 5G network are described, encompassing virtual reality, augmented reality, massive content transmission, the Internet of Things, and artificial intelligence. The paper also explores the applications of the 5G network in industry and transportation through examples of smart industrial operations and modern transportation systems connected to the 5G network

Forests of the Slavonian Military Frontier in the 18th Century

U radu se iz ekohistorijske perspektive prikazuju šume Slavonske vojne krajine u 18. stoljeću. Šume se proučavaju kao zasebni ekosistem te kroz njihovu interakciju s čovjekom. Rad se temelji na pregledu izvora – karti Slavonske vojne krajine iz 1780. godine, Šumskih uredbi iz 1787. godine i putopisu austrijskog državnog službenika Friedricha Wilhelma von Taubea. Naglasak je na prikazu izgleda šuma i njihovih karakteristika te na utjecaju čovjeka kroz ekonomsku eksploataciju i deforestaciju. Predstavljaju se oprečni pogledi vojne vlasti i krajišnika po pitanju korištenja i zaštite šuma.The paper portrays the forests of the Slavonian Military Border in the 18th century from the perspective of ecohistory. The forests are studied as a separate ecosystem and through their interaction with humans. The paper is based on an overview of sources – a map of the Slavonian Military Border from the year 1780, the Forest Decree from the year 1787 and the travelogue of the Austrian civil servant Friedrich Wilhelm von Taube. The paper emphasizes the appearance of forests and their characteristics, as well as man’s influence on forests through economic exploitation and deforestation. The conflicting views of the military authorities and the frontier soldiers on the use and protection of forests are presented

Properties of particleboards produced from bleached wood chips

Današnji razvoj ekološke svijesti o nužnosti smanjenja ekološkog otiska i recikliranja materijala primorao je proizvođače ploča iverica na traženje alternativnih izvora za izradu drvnog iverja. Tako se danas sve više koristi drvni reciklat kojeg mahom čine staro otpadno drvo u svim oblicima, povučeno iz uporabe, odnosno jedno i višegodišnji izbojci plantažnih voćkarica. U odnosu na namjenski iverano drvo iz metrica i višemetrica, priprema drvnog iverja iz reciklata rezultira s velikim udjelom drvne prašine i općenito čestica drva manjih dimenzija, koje uz to imaju i neatraktivnu i nepoželjnu tamnu boju. Upravo s ciljem da se proba doskočiti potonje navedenom problemu, u sklopu ovog završnog rada provedeno je izbjeljivanje industrijski proizvedenih smjesa iverja za vanjske i središnji sloj troslojnih ploča iverica, te izrada i ispitivanje svojstava eksperimentalnih ploča iverica izrađenih primjenom takvog iverja