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We have here an insight into the features of molecular structures of bio-polymers with α-helix structure using infrared spectrum and elucidated theoretically, its relationship with bio-functions. In this case, we analyzed first the features of molecular structure of collagen and collected further the infrared spectrum of absorption of collagen and bovine serum albumin containing α-helix conformation in 400–4000 cm^-1 as well as their changes of strength of infrared absorption with varying temperatures using Fourier Transform–Infrared (FT-IR) spectrometers in the region of 15–95°C. The results show that there is a new band of 1650 cm^-1 close to the amide-I band of 1666 cm^-1 or 1670 cm^-1 in these bio-polymers, its strength decreases exponentially with increasing temperature of the systems, which can be expressed by exp[-(0.437 + 8.987 × 10^-6 T²)], but 1666 cm^-1 band increases linearly with increasing temperature. We calculated the energy spectrum of the protein molecules with α-helix conformation using the Soliton Theory of bio-energy transport, which are basically same with the experimental results measured by us. From these results and soliton theory we can conclude that the nonlinear soliton excitation, corresponding to 1650 cm^-1 band and the exciton excitation, is related to 1666 cm^-1 band, exists in the collagen and bovine serum albumin. In the meanwhile, these results also verified that the soliton theory of bio-energy transport along α-helix bio-polymers is appropriate to the protein molecules with α-helix conformation. Therefore, the studied results are helpful to elucidate the relationship between the molecular structure and bio-function of these bio-polymers.

Single crystals of 2-Naphthalenol (2N), new organic nonlinear optical (NLO) material, have been grown by slow evaporation solution growth technique at room temperature. The crystal system has been confirmed from the single crystal X-ray diffraction analysis. The functional groups were identified using FTIR spectroscopy. UV-vis-NIR spectrum showed absence of absorption in the wavelength region 400–1400 nm. The second harmonic generation efficiency is two times higher than that of standard potassium dihydrogen phosphate (KDP).

Zn (1, 3, 5, 7 mol.%): Dy: LiNbO₃ crystals were prepared by the traditional vertical pull-up method. The effective segregation coefficients of ${\text{Zn}}^{2+}$ and ${\text{Dy}}^{3+}$ were found to decrease with increasing ${\text{Zn}}^{2+}$ concentration using ICP-AES analysis test. The lattice size was found to increase first and then decrease using XRD analysis test. The absorption spectrum was found blue shifted and produced two peaks using IR. Research shows that when the Zn content reaches or exceeds the threshold value, ${\mathrm{\text{Nb}}}_{\mathrm{\text{Li}}}^{4+}$ is replaced completely, and Zn occupies the Li and Nb positions of lithium niobate, thus introducing the non-intrinsic defect ${\mathrm{\text{Zn}}}_{\mathrm{\text{Li}}}^{+}$ and ${\mathrm{\text{Zn}}}_{\mathrm{\text{Nb}}}^{3-}$. Both defects are able to form ${\mathrm{\text{3Zn}}}_{\mathrm{\text{Li}}}^{+}-{\mathrm{\text{Zn}}}_{\mathrm{\text{Nb}}}^{3-}$ charge self-compensating defect groups and inhibit the charge transport process and thus will greatly increase the photodamage resistance.

Single crystals of the metal-organic nonlinear optical material bis thiourea lead chloride were grown from solution growth technique for the first time. The grown crystals were characterized by single crystal X-ray diffraction analysis to confirm the crystal structure. The presence of various functional groups and the coordination of metal ions to thiourea were confirmed by Fourier transform infrared analysis. UV-Vis. spectrum was recorded to study the optical transparency of the grown crystals. The second order nonlinear optical property of the grown crystal was examined by Kurtz powder technique and mechanical behavior was studied by Vickers micro hardness test.

Using density functional theory, we predicted the solution structure of the hydrolyzed 3–aminopropyltriethoxysilane (h–APS), which is a silane coupling agent commonly used in many industrial applications. We have located five stable minima on the potential energy surface of h–APS in which four of them are "neutral", and the remaining one is zwitterionic (dipolar) in nature. Our calculations suggested that the stability of the most stable form of h–APS in water (denoted as II_N) arose from strong intramolecular OH⋯N hydrogen bond. The least stable form is the zwitterionic form (I_ZW), which is estimated to be over 90kJ mol^-1 less stable than II_N. The factors governing the relative stabilities of different forms are discussed.

An organic compound Bis DL-Valine picrate (BDLVP) was synthesized successfully and single crystal was grown by slow evaporation solution growth method. The presence of functional groups in the compound was identified by FTIR spectral analysis. Single crystal X-ray diffraction study revealed that the grown crystal belongs to P2₁/n space group of monoclinic crystal system. Powder X-ray diffraction pattern was recorded to know the crystalline perfection of the grown crystal. The reaction mechanism, thermal decomposition stages and thermal stability of the grown crystal were studied by using TG/DTA analysis. From the UV-visible spectral study, the electronic band gap energy (E_g) of the grown crystal was found to be 2.43 eV. The second harmonic generation (SHG) efficiency of grown crystal was found to be 1.3 times higher than KDP crystal by using Kurtz powder SHG technique. The microhardness property of the grown crystal was examined by Vicker's microhardness test.

9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), 4-Aminoacetophen-one and 2-Toluidine were used as raw materials and p-toluene sulfonic acid as catalyst, we synthesized a new nitrogenous phosphorous asymmetrical diamine flame retardant. The melting point of flame retardant was 247.8°C by differential scanning calorimetry (DSC); the characteristic peaks of the resultant was tested by Fourier transform infrared spectroscopy(FT-IR), and the proton peak of the resultant was characterized by nuclear magnetic resonance hydrogen spectrum instrument. Experimental results showed that: when the reaction temperature was 150°C, reaction time was 24h, catalyst p-toluene sulfonic acid's dosage was 4% of DOPO, 2-toluidine dosage was 5 times of DOPO, the target's product yield could achieve 65%.