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research Sanayileşme ve teknolojik gelişmeler arttıkça; geniş uygulanabilirliğe sahip, çevre dostu, toksik olmayan, yüksek sıcaklığa ve aleve dayanıklı, fonksiyonel malzeme arayışı da artmaktadır. Bor tüm bu ihtiyaçlara cevap verebilecek stratejik öneme sahip, gelişen sanayi ve teknolojik ilerlemelerin temel girdi maddelerinin başında gelen vazgeçilmez mineral kaynaklarından biridir. Ham ve rafine ürünler dışında genellikle yüksek teknoloji gerektiren metotlar ile rafine bor ürünleri kullanılarak dünyada ticari amaçla üretilen özel bor bileşikleri mevcuttur. Bu özel bor bileşiklerinin her biri farklı sektörlerde belirli amaçlar için kullanılmaktadır. Özel bor bileşiklerinin kullanım amaçlarından biri de alev geciktirici olarak kullanılabilirliğidir. Alev geciktirici katkı maddeleri, yanmanın başlamasını ve ilerlemesini engelleyerek, bazı durumlarda can ve mal güvenliğini, bazı durumlarda da çevreyi korumaya yardımcı olurlar. Yanıcı malzemelerin, daha geç tutuşmalarını sağlayabilmek ve yanmanın ilerlemesini önemli derecede azaltabilmek, alev geciktirici katkı maddelerinin ilavesi ile gerçekleşebilir. Borlu bileşikler alev geciktirici olarak yaygın kullanım alanı bulmuştur. Borlu bileşikler ahşap, selülozik yalıtım, PVC ve tekstil malzemelerine katılarak bu malzemelere güç tutuşurluk özelliği kazandırırlar. Bu çalışmada alev geciktiriciler üzerinde genel bir inceleme yapılmış, borlu bileşiklerin alev geciktirici etkisi yapılan çalışmalar üzerinden gösterilmiştir The search for functional materials which have specialities such as broad applicability, eco- friendly, being non-toxic, durable at high temperature and flame resistance is increasing with industrialization and technological development. Boron is the one of the indispensable mineral resources which can respond the all of these needs, having strategic importance and one of the main input materials of the growing industrial and technological progress. Except of crude and refined products, special boron compounds which are commercially produced by using especially refined boron products with methods which require high technology are available in the world. Each of these special boron compounds is used for specific purposes in different sectors. One of the purpose of use of special boron compounds is that they can use as flame retardant. Flame retardant additives inhibit the initiation and progress of the combustion so that they help to protect in some cases, environment, in some cases, life and property safety. To provide ignition of flammable materials later and to reduce significantly the progress of combustion can be realized by addition of flame retardant additives. Boron compounds have wide usage area as flame retardant. Boron compounds participate in wood, cellulose insulation, PVC and textile materials and they bring flame retarding property to these materials. An overall review have been conducted on the flame retardants in this study and flame retardant effect of boron compounds have been shown through other studies.

Early Access Received: 20 February 2022, Accepted: 27 May 2022, Published online: 05 July 2022. Duygu Yılmaz Aydın, Department of Bioengineering, Faculty of Engineering and Natural Sciences, Malatya Turgut Ozal University, 70 Alacakapı St, 44210 Malatya, Turkey. Metin Gürü2, Department of Chemical Engineering, Faculty of Engineering, Gazi University, 5 Yükselis St, 06570 Ankara, Turkey. Adnan Sözen, Department of Energy Systems Engineering, Faculty of Technology, Gazi University, 6/22 Bandırma St, 06560 Ankara, Turkey. In this paper, the effect of using CaMg(CO3)2/Ethylene Glycol-water (50:50%) as a working fluid on the thermal performance of thermosyphon heat pipe was experimentally studied. Nanofluid was prepared by two-step method using 2% concentration of CaMg(CO3)2 nanoparticle and 0.05% surfactant (Sodium dodecylbenzene sulfonate). For the experimental set-up, a straight copper pipe of one-meter length was used. The inner diameter of the pipe is 13 mm, and the outer diameter is 15 mm. Experiments were conducted at three different cooling water mass flow rates (5, 7.5, and 10 g/s) and different heating powers (200, 300, 400 W) to test heat pipe performance. It was observed that the CaMg(CO3)2 nanofluid reduced the average wall temperature of the heat pipe according to the base fluid. Furthermore, the efficiency and thermal resistance of the heat pipe were investigated separately for EG/water and CaMg(CO3)2 nanofluid. The maximum heat transfer enhancement was obtained as 9.55% under 400 W heating power and 10 g/s cooling water mass flow rate conditions and the maximum improvement in thermal resistance was observed as 21% at 200 W and 10 g/s cooling mass flow rate. Viscosity and specific heat of base fluid and CaMg(CO3)2 nanofluid were also determined and compared to each other.

Bu çalışmada özel bor bileşiklerinden olan kalsiyum floroboratın sentez parametreleri belirlenmiş ve pamuklu kumaştaki alev geciktirici özelliği incelenmiştir. Ayrıca kinetik çalışmalar yapılarak reaksiyon mertebesi ve aktivasyon enerjisi hesaplanmıştır. Kalsiyum floroborat, reaktant olarak kalsiyum oksit ve floroborik asit kullanılarak yaş yöntemle sentezlenmiştir. İncelenen parametreler; reaktant mol oranı (nCaO/nHBF4), sıcaklık ve reaksiyon süresidir. Karakterizasyon çalışmaları için FT-IR, XRD ve BF4- iyon seçici elektrot kullanılmıştır. Termal davranışın karakterize edilmesinde termogravimetrik-diferansiyel termal analiz (TG-DTA) kullanılmıştır. Kalsiyum floroborat, 1:4 reaktant mol oranı, 90˚C sıcaklık ve 100 dakika reaksiyon süresinde %97 verimle sentezlenmiştir. Ayrıca yapılan kinetik çalışmada reaksiyonun birinci mertebeden olduğu belirlenmiş ve reaksiyonun aktivasyon enerjisi 19,14 kJ/mol olarak bulunmuştur. Sentezlenen kalsiyum floroboratın alev geciktirici özelliğini tespit etmek için LOI testinden yararlanılmıştır. Testler sonucunda kalsiyum floroboratın çok iyi alev geciktirici özellik gösterdiği gözlemlenmiştir. In this study, the synthesis parameters of calcium fluoroborate, one of the special boron compounds, were determined and its flame retardant properties in cotton fabric were investigated. In addition, kinetic studies were carried out to calculate the reaction order and activation energy. Calcium fluoroborate was synthesized by wet method using calcium oxide and fluoroboric acid as reactants. The parameters examined were reactant mole ratio (nCaO/nHBF4 ), temperature and reaction time. FT-IR, XRD and BF4 - ion selective electrode were used for characterization studies. Thermogravimetric-differential thermal analysis (TG-DTA) was used to characterize the thermal behavior. Calcium fluoroborate was synthesized with 97% yield when molar ratio of reactants, temperature and reaction time are set as 1:4, 90°C and 100 minutes, respectively. In addition, kinetic experiments reveal that the reaction order obeys to first order kinetics and the activation energy was found as 19.14 kJ/mol. LOI tests were used to determine the flame retardant properties of synthesized calcium fluoroborate. Tests proved that the calcium fluoroborate has very good flame retardant properties.

Türkiye, etrafı denizlerle çevrili bir ülke olması sebebiyle deniz araçlarında kullanılan boyalar oldukça önemli hale gelmektedir. Cu2O2 içeren antifouling boyaların salınım sınırlamalarında kontrol gerekmektedir ve bakır içermeyen çevre dostu antifouling boyaların kullanımının zorunlu olacağı öngörülmektedir. Deniz araçlarında kullanılan antifouling boya pigmenti ilk olarak milli kaynaklardan sentezlenecek olup antifouling boya piyasasındaki ihtiyaç karşılanmış olacaktır. Bu çalışmada ilk olarak özel bor bileşiklerinden biri olan fenil floroborat sentez parametreleri belirlenerek daha sonra elde edilen pigmentin boyada kullanılabilirliği ve disk yöntemi ile antibakteriyel özelliği test edilmiştir. Yaş yöntem ile fenil floroborat sentezinde reaktant olarak fenol ve floroborik asit kullanılmış olup H2SO4 katalizör olarak tercih edilmiştir. Reaktant mol oranı ((nC6H5OH / nHBF4) = 1:1; 1,5:1; 2:1 ve 2,5: 1), sıcaklık (30 °C, 35 °C, 40 °C, 50 °C ve 60 °C) ve reaksiyon veriminde etkili reaksiyon süresi sentez parametreleri olarak incelenmiştir. Karakterizasyon çalışmaları için FT-IR ve BF4- iyon seçici elektrot kullanılmıştır. Fenil floroborat, reaktant mol oranı, sıcaklık ve reaksiyon süresi sırasıyla 2:1, 35 °C ve 90 dakika olduğunda % 62 verimle sentezlenmiştir. Pigment epoksi tür bağlayıcı ile solvent bazlı antifouling boya haline dönüştürülmüş olup deniz suyunda bekletildiğinde boya formunu korumuştur. Antibakteriyel aktivite, agar disk difüzyon yöntemi kullanılarak incelenmiş olup boya halindeki numunede difüzyondan kaynaklı antibakteriyel özellik görünmezken fenil floroborat pigmenti antibakteriyel özellik göstermiştir., Due to the fact that Turkey is a country surrounded by seas, the paints used in marine vehicles become very important. It is necessary to control the emission limitations of antifouling paints containing Cu2O2 and it is foreseen that the use of eco-friendly antifouling paints that do not contain copper will be mandatory. The antifouling paint pigment used in marine vehicles will first be synthesized from national sources and thus the need in the antifouling paint market will be met. In this study, firstly, the synthesis parameters of phenyl fluoroborate, one of the special boron compounds were determined and then the usability of the obtained pigment in paint and its antibacterial properties were tested with the disc method. Phenol and fluoroboric acid were used as reactants in the synthesis of phenyl fluoroborate by wet method and H2SO4 was preferred as catalyst. Mole ratio of reactant ((nC6H5OH / nHBF4) = 1:1; 1,5:1; 2:1 and 2,5:1), temperature (30 °C, 35 °C, 40 °C, 50 °C and 60 °C) and reaction time that affect the reaction yield as synthesis parameters were investigated. FT-IR and BF4- ion selective electrodes were used for characterization studies. Phenyl fluoroborate was synthesized with 62% yield at a mole ratio of reactants of 2:1, 35 °C and 90 minutes. The pigment was converted into a solvent-based antifouling paint with an epoxy type binder and kept its paint form when immersed in sea water. Antibacterial activity was investigated using the agar disc diffusion method, and while the antibacterial property due to diffusion was not observed in the paint sample, the phenyl fluoroborate pigment showed antibacterial property.

The use of herbs in treatment has started with the history of humanity and a significant number of effective drugs are being developed from herbal sources. Primary and secondary metabolites, which are natural products produced by plants, are the most basic products of the industry directly or indirectly. One of these groups is alkaloids. Alkaloids show antiviral effects in viral diseases. COVID-19, which started in China and spread to many countries, has become an epidemic that threatens all humanity worldwide as "Coronavirus Pandemic". No reliable and certified drug has yet been developed for this virus. Recent important research shows that plant-based substances can be potential candidates for developing effective and safe drugs against this virus. Referring to such recent studies, this study primarily shows that the antiviral potentials of some alkaloids especially quinine and artemisinin and its derivatives. In addition, the importance of antiviral plant substances in the development of a broad-spectrum drug for SARS-CoV-2 is emphasized.