Time filter

Source Type

Li Y.,Xian Modern Chemistry Research Institute | Tang T.,Xian Ruilian Modern Electronic Chemicals Co. | Lian P.,Xian Modern Chemistry Research Institute | Luo Y.,Xian Modern Chemistry Research Institute | And 5 more authors.
Chinese Journal of Organic Chemistry

Using 3,5-dimethyl-4-aminopyrazole as primary substance, l,4-diamino-3,6-dinitropyrazolo[4,3-c]pyrazole (LLM-119) was synthesized by six steps of diazotisation, intramolecular cyclic condensation, nitration, oxidation, decarboxylation nitration and N-amination. The structures of intermediates and target compound were confirmed by means of IR, 1 H NMR, 13 C NMR and elemental analysis. The post-treatment method of 4-diazonium-3,5-dimethylpyrazole salt was improved, the yield was increased from 77.0% to 86.1% because of using the freezing crystallization method instead of extractive method, which could avoid the use of organic reagent and shorten operation process. The mechanism of N-amination reaction was discussed in order to analyze the reason of low-yield theoretically. Using differential scanning calorimetry (DSC) and thermogravimetric (TG) as thermal analysis methods, the thermal performance of LLM-119 was studied with thermal decomposition peak temperature of 232.05 °C and the results showed that LLM-119 had preferable thermal stability. The structure of LLM-119 was also estimated by a B3LYP method on 6-31G(d,p) basis set in order that its steady geometric configuration and bond order were obtained. The vibrational frequencies, IR spectra and thermodynamics properties in different temperatures of the system were obtained on the basis of vibrational analysis, the relations of the effects of temperatures on thermodynamics properties were also obtained. The density of LLM-119 calculated through the Monte-Carlo method was 1.85 g/cm 3, which approached with the experiment value, and the predicted detonation velocity was 8733.94 m/s by the formula of Kamlet. © 2012 Chinese Chemical Society & SIOC, CAS. Source

Zhu S.,Shaanxi Normal University | An Z.,Shaanxi Normal University | An Z.,Xian Modern Chemistry Research Institute | Chen X.,Shaanxi Normal University | And 2 more authors.
RSC Advances

The modification of π-linkers represents a viable strategy to improve the performance of organic dye in dye-sensitized solar cells (DSSCs). On the basis of the π-linker modification, four cyclic thiourea functionalized dyes (AZ260, AZ261, AZ262, and AZ263) were synthesized and their effects on the short-circuit current density (Jsc) and open-circuit voltage (Voc) were investigated. The results showed that AZ261 bearing an n-hexyl chain on the π-linker generated higher Jsc (16.02 mA cm-2) and Voc (739.4 mV) than AZ6 without a substituent on the bithiophene (Jsc = 15.89 mA cm-2, Voc = 729.2 mV, PCE = 7.20%), and a higher PCE of 7.42% was obtained from AZ261. Furthermore, insertion of a double-bond into the π-linker (AZ263) yielded the highest Jsc (17.83 mA cm-2) with a somewhat lower Voc (719.2 mV), and delivered the highest PCE up to 8.24%. In addition, the function of mesoporous spherical TiO2 on the photoanodes were also systematically examined and proven to be beneficial in increasing the Jsc. This journal is © the Partner Organisations 2014. Source

Zhu S.,Shaanxi Normal University | An Z.,Shaanxi Normal University | An Z.,Xian Modern Chemistry Research Institute | Chen X.,Shaanxi Normal University | And 2 more authors.
Dyes and Pigments

A series of cyclic thiourea functionalized dyes containing binary π-linkers were synthesized and applied in the dye-sensitized solar cells. The only difference of these dyes is that one segment of the binary π-linkers is thiophene, n-hexylthiophene, thienothiophene, 3,4-ethylenedioxythiophene, and benzene, respectively. Among them, the dyes incorporating electron-rich thienothiophene or 3,4-ethylenedioxythiophene exhibit the broader absorption bands and higher molar extinction coefficients in the visible region, which can not only enhance the light-harvesting ability but also improve the short-circuit current density; on the other hand, the dyes bearing bulky n-hexylthiophene or 3,4-ethylenedioxythiophene can effectively suppress the intermolecular π-π aggregation and electron recombination owing to larger steric hindrance, which is beneficial to increase the open-circuit voltage. © 2015 Elsevier Ltd. All rights reserved. Source

Xie M.-Z.,Xian Modern Chemistry Research Institute | Feng X.-Q.,Xian Ruilian Modern Electronic Chemicals Co. | Heng S.-Y.,Xian Modern Chemistry Research Institute | Wang X.-H.,Xian Modern Chemistry Research Institute | And 4 more authors.
Hanneng Cailiao/Chinese Journal of Energetic Materials

The effects of two nano burning rate catalysts (nano lead 2,4-dihydroxybenzoate and nano lead phthalate) on thermal decomposition of double-based propellants were studied using TG-DSC-IR simultaneous techniques and combined solid reaction cell in-situ and RSFT-IR. The characteristic values for TG-DTG and DSC of the condensed phase and the gas products were measured in real time. Results show that the nano lead salt catalysts change on the characteristic values of the thermal decomposition, and shorten the decomposition course and accelerate the exothermic rating. The split of O-NO2 bond and framework in NC/NG component are facilitated. The relative quantities of CH2O, CO and CO2 (with negative forming heat ΔHf o) produced from the decomposition of NC/NG components increase. Compared with the blank control propellant, the exothermic rating of the propellants with n-β-Pb and n-PhtP increase from 29.5 J · g-1 · ° C-1 to 31.1 J · g-1 · °C-1 and 31.4 J · g-1 · °C-1 respectively; the ratios of CH2O/NO2 increase from 1.77 to 2.45 and 2.60 respectively; the ratios of CO/NO2 increase from 0.071 to 0.079 and 0.090 respectively. The propellant with nano lead phthalate has the rapidest exothermic rating, and the largest relative quantity of CH2O and CO, and the highest burning rate too. Source

Wei Y.,Shaanxi Normal University | Wu Z.,Shaanxi Normal University | An Z.,Shaanxi Normal University | An Z.,Xian Modern Chemistry Research Institute | And 3 more authors.
Chinese Journal of Chemistry

Approach to highly efficient dye-sensitized solar cells (DSSCs) by co-sensitization of organic dyes, AZ6+AZ5 with co-adsorbent chenodeoxycholic acid (CDCA) is presented. The power conversion efficiencies (PCEs) of 8.55% and 8.31% are obtained from DSSCs co-sensitized by AZ6 (0.3 mmol/L)+AZ5 (0.1 mmol/L) with CDCA concentration of 5 and 20 mmol/L in one step cocktail, respectively. The latter shows high stability in a period of 653 h under ambient conditions. Copyright © 2014 SIOC, CAS, Shanghai & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Discover hidden collaborations