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Article Synthesis of Silver Nanoparticle-Immobilized Antibacterial Anion Exchange Membranes for Salinity Gradient Energy Production by Reverse Electrodialysis(ACS Sustainable Chemistry & Engineering, 2024-03-01) Eti, Mine; Cihanoğlu, Aydın; Hamaloğlu, Kadriye Özlem; Altıok, Esra; Güler, Enver; Tuncel, Ali; Kabay, NalanBiofouling, stemming from the attachment of living microorganisms, such as bacteria, which form resilient biofilms on membrane surfaces, presents a significant challenge that hampers the efficiency of anion exchange membranes (AEMs) in reverse electrodialysis (RED) applications. This limitation curtails the generation of electrical power from salinity gradients, which, notably, is a sustainable form of energy known as osmotic energy. Reverse electrodialysis (RED) stands as a clean and promising process to harness this sustainable energy source. This study aimed to impart antibacterial activity to the synthesized AEMs using silver nanoparticles (AgNPs). For that purpose, AgNPs were synthesized at 30oC using two different pH (6.0 and pH 9.0) and immobilized into synthesized AEMs using the dip-coating technique. In nanoparticle synthesis, ascorbic acid (AA) and trisodium citrate (TSC) were used as a reductant and a stabilizer, respectively, to take under control of particle size and agglomeration behavior. The results indicated that AgNPs synthesized at pH 6.0 were dispersed on the AEMs surface without agglomeration. The stability of AgNPs immobilized on the membrane surface was tested under low and high-saline solutions. The antibacterial activities of AEMs were determined with the colony-counting method using Gram-negative (Escherichia coli) bacteria suspension. The viability of bacteria dramatically decreased after the immobilization of AgNPs to the AEMs. In the short and long-term RED tests, it has been observed that the AEMs having AgNPs have high energy-generating potentials, and power density up to 0.372 W/m2 can be obtained.Article D-A-D type conjugated polymers in dual electrochromic devices tuning from green to blue colors(Synthetic Metals, 2023-07) İçli Özkurt, Merve; Önal, Ahmet M.; Cihaner, AtillaIn this study, the electrochemical and electro-optical properties of four different dual electrochromic devices were unraveled. In all devices, soluble donor-acceptor-donor (D-A-D) type conjugated electrochromic polymers based on didecyl substituted 3,4-propylenedioxythiophene and heterodiazole analogues were used, and they were coated on ITO electrochemically for the construction of the electrochromic devices. Because all D-A-D polymers and PEDOT are colorful in their neutral states and colorless in their oxidized states, it is possible to observe one-to-one colors of pure two polymers in their electrochromic devices rather than a mixture of colors. It was observed that devices changed their colors from the tunes of green to blue under applied external voltage. Switching times, coloration efficiencies and stabilities of the electrochromic devices were calculated as ranging from 1.0 to 6.0 s, 133 to 544 cm2/C and 54% to 91%, respectively, after 5000 cycles. The P(PSeP-C10)-P(PNP-C10) device showed the highest coloration efficiency (544 cm2/C) as well as the best optical and electrochemical stabilities among the electrochromic devices after 5000 cycles (91% and 92%, respectively).Article Side Chain effect on the electrochemical and optical properties of TPD based donor acceptor donor type monomers and polymers(Molecular Systems Design and Engineering, 2023) Çakal, Deniz; Demir Arabacı, Elif; Yıldırım, Erol; Cihaner, Atilla; Önal, Ahmet M.In organic π-conjugated materials, side chains play great roles that are far beyond solubility. In this work, we mainly focused on the synthesis of new donor-acceptor-donor (D-A-D) type conjugated monomers and their corresponding polymers appending TPD acceptor with a new side chain, fluorene, to investigate the side chain effect. In this context, to reveal the precise effect of the side chains on the optical and electrochemical properties of the monomers and polymers synthesized in this work, four series of D-A-D monomers, each containing a TPD core unit with a different side chain, have been discussed in comparison to each other. Notably, it was discovered that TPD acceptor unit can be modified by any functional group other than common alkyl chains to impart new functionalities by keeping their superior optoelectronic properties. New kind of side chains can be used to tune the physical characteristics such as solubility, absorption, emission and molecular packing. In this paper, fluorene-appended monomers as a new class of D-A-D type π-conjugated molecules were studied and it was found that E(Fl) and P(Fl) exhibited resonable quantum yields and their corresponding polymers revealed ambipolar character with slightly lower band gap as compared to the previous analougs containing other side chains. Observed experimental results were elucidated by first principle calculations. In this paper, we discussed that using side chain engineering is an effective strategy to improve next-generation organic π-conjugated materials with the desired properties.Article Synthesis and Characterization of A Luminol Based Chemiluminescent Trimeric System(Journal of Fluorescence, 2023-07) Kesimal, Büşra; Balcı, Burcu; Çakal, Deniz; Önal, Ahmet M.; Cihaner, AtillaA luminol based chemiluminescent trimeric system, namely 2,3-dihydro-5,8-di(thiophen-2-yl)phthalazine-1,4-dione (T2B-Lum), bearing thiophene rings as donor units and 2,3-dihydrophthalazine-1,4-dione as an acceptor unit was synthesized in two steps via donor-acceptor-donor approach using two different methods. It was found that T2B-Lum emits chemiluminescent light when exposed to H2O2 in a basic medium, and the presence of substituents and the type of aromatic ring bearing chemiluminescent active group have a direct effect on the compound's sensitivity. Among the members of a large family of metal ions, fluorescent and chemiluminescent T2B-Lum exhibited high sensitivity to Cu2+ and Fe3+ ions. Except for other metal cations (silver(I), cadmium(II), cobalt(II), iron(III), lithium(I), magnesium(II), manganese(II), nickel(II), zinc(II)), it has been observed that T2B-Lum is mostly sensitive to copper(II) ions with a detection limit value of 2.2×10-3 M. On the other hand, T2B-Lum was also found to exhibit a high sensitivity to extremely dilute aqueous solutions (e.g., 1:50.000 dilution) of blood samples, making it a promising candidate for use in forensic applications.Article Synthesis, Characterization and Application of High Sulfur Content Polymeric Materials from Fatty Acids(Reactive and Functional Polymers, 2023-06) Berk, Hasan; Kaya, Murat; Topçuoğlu, Mert; Türkten, Nazlı; Karataş, Yunus; Cihaner, AtillaA new series of high sulfur content polymers containing various amounts of fatty acids (oleic acid (OA), linoleic acid (LA) and linolenic acid (LnA)) was synthesized via inverse vulcanization method and characterized successfully. In particular, the effect of double bonds and free alkyl chains on polysulfur copolymers has been investigated systematically by using OA with one double bond, LA with two double bonds and LnA with three double bonds. The copolymers with functional carboxylic acid groups are soluble in common organic solvents, processable and electroactive. Also, the usage of the copolymers was tested in the removal of methylene blue and as a cathode material in Li-S battery. Results showed that the polymers can be a potential material for use in dye removal.Article Effect of phthalimide and thieno[3,4-c]pyrrole-4,6,dione acceptors on π-conjugated donor-acceptor-donor monomers: Experimental and theoretical investigations of photophysical and electrochemical properties(Tetrahedron, 2023-06-29) Çakal, Deniz; Demir Arabacı, Elif; Yıldırım, Erol; Cihaner, Atilla; Önal, Ahmet M.In this study, two novel donor-acceptor-donor monomers were synthesized by coupling a phthalimide (PI) acceptor unit with thiophene (T) and ethylenedioxythiophene (EDOT (E)) donor units. These two novel PI-based monomers, namely 2-(2-ethylhexyl)-4,7-di(thiophen-2-yl)isoindoline-1,3-dione (T-PI) and 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-(2-ethylhexyl)isoindoline-1,3-dione (E-PI), were fully characterized via UV-vis and fluorescence spectroscopy as well as electrochemical methods, and the results were directly compared with those of previously synthesized thieno[3,4-c]pyrrole-4,6-dione (TPD)-based analogues to report the results for four classes of monomers. In this regard, the effects of different donor groups and structural modifications in the acceptor unit as changed from PI to TPD have been investigated to reveal the precise effect of the donor and acceptor on the optical and electrochemical properties of the monomers. All monomers exhibits an intramolecular charge transfer band in the low energy region due to strong donor and acceptor interactions. The oxidation and reduction potentials of the monomers are found to vary depending on the strengths of both donor and acceptor units. PI-based monomers show more positive oxidation and less negative reduction potentials than TPD-based analogues. Similarly, thiophene-based analogues reveal the same trend in their oxidation and reduction potentials as compared to EDOT-based analogues. Lastly, PI-based monomers could not undergo polymerization via electrochemical method, unlike TPD-based monomers, since the dihedral angle arising between donor and PI acceptor disturbs molecular planarity significantly, as demonstrated by first principle calculations.Article New Generation Radiation-Grafted PVDF-g-VBC based Dual-Fiber Electrospun Anion Exchange Membranes(International Journal of Hydrogen Energy, 2024-01-02) Kırlıoğlu, Ahmet Can; Mojarrad, Naeimeh Rajabalizadeh; Alkan Gürsel, Selmiye; Güler, Enver; Yarar Kaplan, BegümAnion Exchange Membranes (AEM) have the potential to solve the cost issues of fuel cell technologies due to their basic environment that can allow the use of cheaper components. However, there is still a need to develop an ideal inexpensive, mechanically robust AEM with high ionic conductivity and ion exchange capacity (IEC). In this work, we present various dual-fiber electrospun membranes based on a novel radiation-grafted copolymer. First, the synthesis route of radiation-induced grafting of vinyl benzyl chloride (VBC) onto poly(vinylidene fluoride) (PVDF) to prepare PVDF-g-VBC was optimized. Then, PVDF-g-VBC powders were used to fabricate dual-fiber electrospun mats with inert PVDF and commercial Fumion-FAA-3 ionomer. Dual-fiber electrospun mats were hot-pressed and then quaternized with trimethylamine. Finally, mechanical properties, ion exchange capacity, ionic conductivity, and morphology of these prepared dual-fiber electrospun membranes were investigated. The dual-fiber membrane prepared with PVDF-g-VBC (88% of the total weight of the membrane) and PVDF: Fumion-FAA-3 (1:2) mix (12 wt%) realized ionic conductivity of 4.67 mS/cm at 25 oC, high ion exchange capacity of 1.35 mmol/g with Young’s Modulus of 761 MPa. The membrane based on the combination of radiation grafting and dual-fiber electrospinning was prepared for the first time in literature and offers the prospect of tuning and fine-control of mechanical and physicochemical properties of AEMs.Article Salinity gradient energy conversion by custom-made interpolymer ion exchange membranes utilized in reverse electrodialysis system(Journal of Environmental Chemical Engineering, 2023-04-15) Altıok, Esra; Kaya, Tuğçe Zeynep; Smolinska-Kempisty, Katarzyna; Güler, Enver; Kabay, Nalan; Tomaszewska, Barbara; Bryjak, MarekReverse electrodialysis (RED) is one of methods to extract salinity gradient energy between two aqueous solutions with different salt concentrations. In this work, custom-made interpolymer ion exchange membranes were employed in the RED stack. The effects of divalent (Mg2+, Ca2+ and SO42-) and monovalent (Li+, K+ and Cl-) ions in the feed solutions prepared from NaCl salt as a function of such process parameters as number of membrane pairs, flow rate, and salinity ratio on power generation by the RED method were studied. It was shown that the maximum power density of 0.561 W/m2 was reached by using three membrane pairs using 1:45 of salt ratio with a feed flow rate of 120 mL/min using only NaCl salt in the feed solutions. The maximum power density was 0.398 W/m2 at 120 mL/min of the flow rate of the feed solutions composed of 90 wt% NaCl and 10 wt% KCl by using a salt ratio of 1:30 while the lowest power density of 0.246 W/m2 was obtained with a feed flow rate of 30 mL/min in the presence of SO42- ions with a similar salt ratio. Consequently, it was seen that while the presence of divalent ions in NaCl solutions had negative impact on power generation by RED system, the addition of monovalent ions having smaller hydrated radius than that of the Na+ ions contributed positively to the power generation.Item Natural bond orbital, nuclear magnetic resonance analysis and hybrid-density functional theory study of σ-aromaticity in Al2F6, Al2Cl6, Al2Br6 and Al2I6(Journal of Molecular Modeling, 2013-02-11) NORI-SHARGH, Davood; YAHYAEI, Hooriye; MOUSEVI, Seiedeh Negar; MAASOOMI, Akram; KAYI, HakanNatural bond orbital (NBO), nuclear magnetic res onance (NMR) analysis and hybrid-density functional theory based method (B3LYP/Def2-TZVPP) were used to investigate the correlation between the nucleus-independent chemical shifts [NICS, as an aromaticity criterion], σAl(1)-X2(b) → σ*Al(3)-X4(b) electron delocalizations and the dissociation ener gies of Al2F6, Al2Cl6, Al2Br6 and Al2I6 to 2AlX3 (X=F, Cl, Br, I). The results obtained showed that the dissociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6 decrease from Al2F6 to Al2I6. Like aromatic molecules, these compounds have relatively significant negative NICSiso(0) values. Clearly, based on mag netic criteria, they exhibit aromatic character and make it possible to consider them as σ-delocalized aromatic species, such as Möbius σ-aromatic species. The σ-aromatic character which is demonstrated by their NICSiso(0) values decreases from Al2F6 to Al2I6. The NICSiso values are dominated by the in-plane σ22 (i.e., σyy, the plane containing halogen atoms bridged) chemical shift components. The increase of the NICSiso values explains significantly the decrease of the corre sponding dissociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6. Importantly, the NBO results suggest that in these compounds the dissociation energies are controlled by the stabilization energies associated with σAl(1)-X2(b) →σ*Al(3)- X4(b) electron delocalizations. The decrease of the stabilization energies associated with σAl(1)-X2(b) →σ*Al(3)-X4(b) electron delocalizations is in accordance with the variation of the calculated NICSiso values. The correlations between the dis sociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6, σAl(1)- X2(b) →σ*Al(3)-X4(b) electron delocalizations, natural atomic orbitals (NAOs) and NICSiso values have been investigated.Item Conformational behaviors of trans-2,3- and trans-2,5-dihalo 1,4-diselenanes. A complete basis set, hybrid-density functional theory study and natural bond orbital interpretations(Journal of Molecular Modeling, 2014-05-14) NORİ-SHARGH, Davood; MOUSAVI, Seiedeh Negar; KAYI, HakanComplete basis set CBS-4, hybrid-density func tional theory (hybrid-DFT: B3LYP/6-311+G**) based methods and natural bond orbital (NBO) interpretations have been used to examine the contributions of the hyperconjugative, electrostatic, and steric effects on the con formational behaviors of trans-2,3-dihalo-1,4-diselenane [halo=F (1), Cl (2), Br (3)] and trans-2,5-dihalo-1,4- diselenane [halo = F (4), Cl (5), Br (6)]. Both levels of theory showed that the axial conformation stability, compared to its corresponding equatorial conformation, decreases from com pounds 1→3 and 4→6. Based on the results obtained from the NBO analysis, there are significant anomeric effects for compounds 1-6. The anomeric effect associated with the electron delocalization is in favor of the axial conformation and increases from compounds 1→3 and 4→6. On the other hand, dipole moment differences between the axial and equa torial conformations [Δ(μeq - μax)] decrease from compounds 1→3. Although Δ(μeq-μax) parameter decreases from com pound 1 to compound 3, the dipole moment values of the axial conformations are smaller than those of their corresponding equatorial conformations. Therefore, the anomeric effect as sociated with the electron delocalizations (for halogen-C-Se segments) and the electrostatic model associated with the dipole-dipole interactions fail to account for the increase of the equatorial conformations stability on going from com pound 1 to compound 3. Since there is no dipole moment for the axial and equatorial conformations of compounds 4-6, consequently, the conformational preferences in compounds 1-6 is in general dictated by the steric hindrance factor asso ciated with the 1,3-syn-axial repulsions. Importantly, the CBS-4 results show that the entropy difference (ΔS) between the equatorial axial conformations increases from compounds 1→3 and 4→6. This fact can be explained by the anomeric effect associated with the electron delocalization which affects the C2-Se bond orders and increase the rigidity of the corre sponding rings. The Gibbs free energy difference values be tween the axial and equatorial conformations (i.e. ΔGax-ax and ΔGeq-eq) of compounds 1 and 4, 2 and 5 and also 3 and 6 have been calculated. The correlations between the anomeric effect, electrostatic model, ΔGeq-ax, ΔGax-ax, ΔGeq-eq, bond orders, dipole-dipole interactions, structural parameters and confor mational behaviors of compounds 1-6 have been investigated.Item Correlations between hardness, electrostatic interactions, and thermodynamic parameters in the decomposition reactions of 3-buten-1-ol, 3-methoxy-1-propene, and ethoxyethene(Structural Chemistry, 2014-08-11) HASANZADEH, Neda; NORİ-SHARGH, Davood; KAYI, Hakan; JAVID, Nargess RezaiDecomposition of the three isomeric com pounds, 3-buten-1-ol (1), 3-methoxy-1-propene (2), and ethoxyethene (3), at two different (300 and 550 K) tem peratures has been investigated by means of ab initio molecular orbital theory (MP2/6-311?G**//B3LYP/6- 311?G**), hybrid-density functional theory (B3LYP/6- 311?G**), the complete basis set, nuclear magnetic reso nance analysis, and the electrostatic model associated with the dipole–dipole interactions. All three levels of theory showed that the calculated Gibbs free energy differences between the transition and ground state structures (DG=) increase from compound 1 to compound 3. The variations of the calculated DG= values can not be justified by the decrease of the calculated global hardness (g) differences between the ground and transition states structures (i.e., D[g(GS)-g(TS)]). Based on the synchronicity indices, the transition state structures of compounds 1–3 involve syn chronous aromatic transition structures, but there is no significant difference between their calculated synchronicity indices. The optimized geometries for the transition state structures of the decomposition reactions of compounds 1–3 consist in chair-like six-membered rings. The variation of the calculated activation entropy (DS=) values can not be justified by the decrease of D[g(GS)- g(TS)] parameter from compound 1 to compound 3. On the other hand, dipole moment differences between the ground and transition state structures [D(lTS-lGS)] decrease from compound 1 to compound 3. Therefore, the electrostatic model associated with the dipole–dipole interactions jus tifies the increase of the calculated DG= values from compound 1 to compound 3. The correlations between DG=, D[g(GS)-g(TS)], (DS=), k(T), electrostatic model, and structural parameters have been investigated.Item A computational study on 4,7-di(furan-2-yl)benzo[c][1,2,5] thiadiazole monomer and its oligomers(Journal of Molecular Modeling, 2014-04-23) KAYI, HakanThe energy gap, Eg, between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molec ular orbital (LUMO) energy levels that determines the elec tronic and optical properties of 4,7-di(furan-2- yl)benzo[c][1,2,5]thiadiazole (FSF) polymer is calculated by performing quantum chemical calculations. First, we theoret ically investigated the most stable conformers of FSF mono mer and its corresponding oligomers at the B3LYP/6-31G(d) and B3LYP/LANL2DZ levels of theory. We reveal the theoret ical molecular structure of this very recently synthesized novel monomer and its oligomers for the first time in the literature. Our results from the B3LYP/6-31G(d) calculations indicated that FSF polymer has a low HOMO-LUMO gap of 1.55 eV to be in good agreement with the experiments. Experimental design and synthesis of novel conjugated polymers require time-consuming and expensive procedures. The findings from this study are promising for the use of computational methods in the design of the novel conjugated polymers, and help to narrow the materials to be used in design and synthesis of conjugated polymers with desired properties.Item Spectroelectrochemical Investigation of Nuclease Active Pt(II) Complexes Containing Pyrrole Oxime(Electrochimica Acta, 2015-01-28) ALTUNÖZ ERDOĞAN, Deniz; KAYI, Hakan; ÖZALP YAMAN, ŞenizIn this paper, the electrochemical oxidation of three Pt(II) complexes containing pyrrole oxime (HL) having a general formula of [Pt(NH3)Cl(L)] (1), [Pt(L)2] (2), and K[PtCl2(L)] (3) has been investigated by in-situ spectroelectrochemistry in dimethylformamide (DMF). An irreversible metal-based oxidation process occurs during the anodic scan for each of the three complexes. The electronic absorption spectral changes indicate that all the three complexes generate similar Pt(IV) compounds and free ligand. Our experimental data is supported by quantum chemistry calculations utilizing density functional theory. In addition, the frontier orbital energy distributions indicate that electron densities are localized on mainly platinum atom.Item A theoretical investigation of 4,7-di(furan-2-yl)benzo[c][1,2,5]selenadiazole-based donor–acceptor type conjugated polymer(Computational and Theoretical Chemistry, 2014-12-19) KAYİ, Hakan; ELKAMEL, AliQuantum chemical calculations are performed using density functional theory (DFT) to investigate the HOMO–LUMO energy gap of the 4,7-di(furan-2-yl)benzo[c][1,2,5]selenadiazole-based (FSeF) donor– acceptor type conjugated polymer which ascertains the optoelectronic properties and plays a crucial role, especially in polymeric solar cell applications. In this paper, the most stable conformers of the FSeF monomer and its corresponding oligomers are investigated at the B3LYP/Def2TZV and B3LYP/LANL2DZ levels of theory, and their molecular structures are revealed. The band gap of the polymer is determined by linear-fitting and extrapolation of the DFT data. This gap is found to be 1.44 eV and 1.45 eV by the B3LYP/Def2TZV, and B3LYP/LANL2DZ with PCM calculations, respectively. Our theoretical findings related to the band gap of the FSeF polymer (PFSeF) are in good agreement with other experimental stud ies in the literature and, hence, the theoretical methods used in this study are promising for the design of similar donor–acceptor type novel conjugated polymers.Item İlaç Araştırmalarında Yeni Nesil Uygulamalar: Kontrollü İlaç Salımı(Bilim ve Teknoloji, 2012-09-21) İŞGÖR, Belgin S.; KORKMAZ ÖZKAN, Filiz16.yüzyılda yaşamış olan ve bugünkü Modern tıbbın kurucularından sayılan Paracelsus’un “Her şey zehirdir. Zehirle ilacı ayıran dozudur” sözü, bugünkü modern toksikolojinin temeli olan doz-cevap ilişkisine dikkat çekmesi açısından son derece önemlidir. Günümüzde ilaç olarak sunulan sentetik ve doğal kaynaklı kimyasal bileşiklerin vücuda alımı genel olarak ağızdan (oral) katı veya sıvı formlarda, damar ve kas içerisine sıvı enjeksiyonuyla, nazal yol aracılığıyla sprey veya toz formunda inhalatör yardımıyla, veya deriden lokal uygulamalarla gerçekleşmektedir. Vücuda verilen ilaç ilk olarak dolaşım sistemine alınır ve tedavi için hedeflenen dokuya kan damarları ile taşınır. Hedef dokulara ise bu dokulara nüfuz etmiş kılcal damarlar yoluyla ulaşır. İlacın vücuda alımından hedef dokuya taşınması sürecinde, damar yolu üzerinde bulunan tüm dokularca alınıp hücresel mekanizmalarca işlenmesi mümkündür.Item TÜRKİYE'DE TEMEL BİLİMLERİN ÇÖKÜŞÜ(Bilim ve Teknoloji, 2015-11-09) CİHANER, AtillaÖncelikle Türkiye'nin bugünkü bilim ve teknolojideki konumunu görmek ve kat ettiği mesafeyi anlayabilmek için, Türkiye'nin geçmişten bugüne olan bilim ve teknolojinin üç ayağı olarak nitelendirebileceğimiz, bilim politikalarını, bilim üretimini ve bilim anlayışını kısaca göz atmakta fayda var. Osmanlı'daki Batılılaşma, modernleşme ve yenileşme hareketleri 17. yy'ın sonlarına doğru başlayıp (1683 Viyana bozgunu sonrası) 18. yy'ın ilk yarısına kadar sürer. Lale Devri, ilk matbaa'nın kullanımı, II. Mahmut Devri, III. Selim Devri, Tanzimat, vb. olaylar Osmanlı'ını Batılılaşma ve modernleşme serüvenindeki önemli olaylardan birkaçıdır.Item TÜRKİYE’DE TEMEL BİLİMLERİN ÇÖKÜŞÜ(Bilim ve Teknoloji, 2015-11-09) CİHANER, AtillaÜniversitelerdeki ilk çöküşün habercisi, temel bilimler kontenjanında yaşanan sıkıntılar ve kapanan bölümler olmuştur. Yürütülen bilim politikalarının yanlışlığından kaynaklı olarak son yıllarda boş kontenjanlarla gündemde olan temel bilimler programlarıyla ilgili çalışma başlatan YÖK, 2014 yılında 11’den az öğrenci kaydolan devlet üniversitelerindeki programlara artık kontenjan verilmeyeceğini duyurmuştur. Uygulanan bilim politikasının yanlışlığını 2010 yılında üniversitelerin temel bilimler bölümlerine ayrılan kontenjan sayılarından net olarak anlamak mümkündür. Bir yıl öncesinde mevcut kontenjanlar doldurulmamış olmasına rağmen kontenjan sayıları arttırılırken bu bölümlere yerleşen öğrenci sayılarında dramatik bir düşüş görülmüştür. YÖK’ün kontenjan verilmeyeceğine dair yaptığı açıklama bir domino etkisi yaratmış ve sonraki yıllarda temel bilimler bölümleri bir bir kapanmaya başlamıştır.Item Az bilinen fakat potansiyeli yüksek sürdürülebilir bir enerji türü: Mavi Enerji(Herkese Bilim Teknoloji, 2017-08-08) Güler, Enver21. yüzyılda insanoğlunun karşılaştığı ve ileride ziyadesiyle sözkonusu olacak en temel durum enerji, su ve gıdaya olan taleptir. Bu talebin karşılanmasında ise sürdürülebilirlik şimdiki ve gelecek kuşakların temel sorunu olmaya devam edecektir. Su, enerji ve gıda arasındaki sıkı bağ açıkça gösteriyor ki; su ve enerji gıda üretiminde, su enerji üretiminde ve enerji su temini ve üretiminde en temel faktörlerdir [1]. Bunun neticesinde bu üçlü bağlam, 2035 yılında enerjiye olan talebin en fazla değer olarak % 50 olacağını öngörmektedir (Şekil 1). Enerjiye olan bu yüksek talebin yakın gelecekte fosil yakıtlar ile sürdürülebilir şekilde karşılanamayacağı aşikardır. Bu durum, enerjinin sürdürülebilir olarak üretimini sağlayacak alternatif teknikler geliştirilmesini bir öncelik haline getirmiştir.