Two new monomers, 2-benzyl-5,12-dihydro-2H-pyrrolo[3 0 ,4 0 :2,3][1,4]dioxocino [6,7-b]quinoxaline (DPOQ) and 5,12-dihydrothieno[3 0 ,4 0 :2,3][1,4]dithiocino[6,7-b]quinoxaline (DTTQ), were synthesized. The chemical structures of the monomers were characterized by nuclear magnetic resonance ( 1 H NMR), Fourier transform infrared (FTIR) and mass spectra. Copolymer of DPOQ with bithiophene (BT) was synthesized via potentiostatic electrochemical polymerization in acetonitrile-tetrabutylammonium tetrafluoroborate solventelectrolyte couple. For DTTQ, copolymerization with bithiophene was achieved via potentiodynamic method in dichloromethane-tetrabutylammonium hexafluorophosphate solvent-electrolyte couple. Characterizations of the resulting copolymers were performed by cyclic voltammetry (CV), FTIR, scanning electron microscopy (SEM) and UV-Vis spectroscopy. Four-probe technique was used to measure the conductivities of the samples. Moreover, the spectroelectrochemical and electrochromic properties of the copolymer films were investigated. In addition, dual type polymer electrochromic devices based on P(DPOQ-co-BT) and P(DTTQ-co-BT) with poly(3,4-ethylenedioxythiophene) were constructed. Spectroelectrochemistry, electrochromic switching and open circuit stability of the devices were studied. They were found to have good switching times, reasonable contrasts and optical memories.

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In this study, the electropolymerization of ethyl and methyl substituted asymmetrical nitrogen analogs of 3,4-ethylenedioxythiophene (OEt and OMe) were synthesized, characterized and their electrochemical properties were investigated. Both polymers (POEt and POMe) were synthesized electrochemically and characterized using spectroelectrochemical technique to determine optical changes of the resulting polymer films. Electrochemical studies demonstrated that these polymers exhibited a significantly low oxidation potential compared to their analogs reported in the literature. These polymers also provided a low optical bandgap with good optical contrasts. Furthermore, multi-electrochromic properties upon different applied potentials revealed that these polymers have potential applications in electrochromic devices. As a further characterization, their dual type electrochromic devices were constructed with poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) which is transmissive in its both redox states. Devices were characterized via electrochemical and spectroelectrochemical techniques.

In this study, ananatomical and histological study was conducted on the alimentary canal of Tanymecusdilaticollis (Coleoptera: Curculionidae), which is an economic polyphagous pest species, to study the relationship between the structure of the alimentary canal and the feeding habit. Therefore, the structure of the alimentary canal of T. dilaticollis was examined using light and electron microscopies. Results have shown that the alimentary canal in T. dilaticollis is consisted of three separate regions as foregut, midgut, and hindgut structurally between the mouth and the anus, which pass from head, thorax, and abdomen. The foregut consists of pharynx, esophagus, crop and proventriculus and in the crop part, expansion is seen compared to other foregut parts. Midgut of T. dilaticollis is the largest part of digestion system. The anterior region of midgut is twofolds wider than the posterior region. The posterior midgut extends tubularly and it is connected to eightgastric caeca. The hindgut of T. dilaticollis consists of fourparts as pylorus, ileum, colon, and rectum. Well‐developed muscle layers are found near the rectum and genital chamber. These results contribute to further studies on the ecology and biological control agents of Coleoptera and to provide a broad comparison of alimentary canal of Coleoptera species.

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In this study, Chrysolina herbacea female reproductive system, differentiating stages of vitellogenesis, the egg chorion are examined with light and scanning electron microscopies. C. herbacea is chosen for this study because it is considered to be one of the most harmful insects that destroy mint plants, and it is an agricultural pest. Female reproductive system consists of a pair of ovaries, a pair of lateral oviducts, a common oviduct, spermathecae and a genital chamber. The ovary has 18 meroistic telotrophic ovariole. Each ovariole is divided into four regions: terminal filament, germarium, vitellarium and pedicel. Terminal filament is a long tubular structure. Germarium contains trophocytes (nurse cells), young oocytes and prefollicular cells. Vitellarium consists differentiating oogenic stages including developmental periods of previtellogenesis, vitellogenesis and choriogenesis. The ovarioles open into lateral oviduct by pedicel. The single spermatheca is located near the base of the common oviduct. Spermathecae consist of spermathecae reservoir for sperm storage and a short spermathecae duct. C. herbacea eggs are yellow and elongated. The structure of female reproductive system, the egg chorion and larva of C. herbacea are important to understand the outbreak of this insect pest and to biological control this harmful species.