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In this work, a fused-ring [1,2,5]oxadiazolo[3,4- b ]pyridine 1-oxide framework with multiple modifiable sites was utilized to develop novel energetic materials with multiple hydrogen bonds. The prepared materials were characterized, and their energetic properties were extensively investigated. Among those studied, compound 3 exhibited high densities of 1.925 g cm -3 at 295 K and 1.964 g cm -3 at 170 K, with high detonation performances ( D v : 8793 m s -1 and P : 32.8 GPa), low sensitivities ( IS : 20 J, FS : 288 N), and good thermal stability ( T d : 223 °C). N -Oxide compound 4 had higher-energy explosive ( D v : 8854 m s -1 and P : 34.4 GPa) and low sensitivities ( IS : 15 J and FS : 240 N). Compound 7 with a high enthalpy group (tetrazole) was determined as a high-energy explosive ( D v : 8851 m s -1 , P : 32.4 GPa). Notably, the detonation properties of compounds 3 , 4 , and 7 were similar to high-energy explosive RDX ( D v : 8801 m s -1 and P : 33.6 GPa). The results indicated that compounds 3 and 4 were potential low-sensitivity high-energy materials.

A new design strategy for zwitterionic energetic materials was developed, and two gem-dinitromethyl functionalized 5-amino-1,3,4-oxadiazolate inner salts were synthesized and characterized. Compared with common energetic salt analogues, both zwitterionic energetic compounds exhibited higher densities, better detonation performances, and comparable mechanical sensitivities. This design strategy may stimulate the development of additional zwitterionic energetic materials.

A series of fused-ring energetic materials, i.e., 3,6-dinitro-1,4-di(1 H -tetrazol-5-yl)-pyrazolo[4,3- c ]pyrazole ( DNTPP , compound 2 ) and its ionic derivatives (compounds 3 - 8 ), were designed and synthesized in this study. The molecular structures of compounds 2 , 3 , 6 , 7·2H 2 O , and 8 were confirmed using single-crystal X-ray diffraction. Their physicochemical and energetic properties, such as density, thermal stability, heat of formation, sensitivity, and detonation properties (e.g., detonation velocity and detonation pressure), were also evaluated. The results indicate that DNTPP and most of its ionic derivatives are extremely thermally stable and insensitive toward mechanical stimuli. In particular, the thermal decomposition temperature of compound 3 is up to 329 °C, while compounds 7 and 8 are very insensitive (impact sensitivity: >20 J; friction sensitivity: >360 N). Compounds 2 , 3 , and 6 possess good comprehensive properties, including excellent thermal stability, remarkable low sensitivities, and favorable detonation performance. These features show that DNTPP and its ionic derivatives have considerable promise as thermally stable and insensitive energetic materials.

Protonated g-C3N4 nanosheets were prepared by refluxing a mixture containing g-C3N4 and 95% H2SO4 at 80 °C for 1 hour. The obtained g-C3N4 nanosheets showed a similar layer structure to that of g-C3N4 and high water adsorption capacities. They also depicted superior conductivities reaching up to 1.44 × 10-2 S cm-1 at 80 °C and 98% RH, with promising features for proton conductivity materials.

A novel family of hydrophobic triaminocyclopropenium cation based ionic liquids have been synthesized, and their structures and physicochemical properties characterized by NMR and IR spectroscopy, elemental analysis, differential scanning calorimetry, and hypergolic tests. The experimental results showed that all of these ionic liquids exhibited the expected hypergolic reactivity with the oxidizer white fuming nitric acid. Among them, the hypergolic ionic liquid based on the cyanoimidazolylborohydride anion showed excellent integrated properties, including high decomposition temperature (194 °C), high density (0.95 g cm -3 ), moderate viscosity (44 MPa s), ultrafast ignition delay time (6 ms), and high specific impulse (301.9 s); this demonstrates its potential as an environmentally friendly alternative to toxic hydrazine derivatives., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The experimental detection and synthesis of pentazole (HN 5 ) and its anion (cyclo-N 5 - ) have been actively pursued for the past hundred years. The synthesis of an aesthetic three-dimensional metal-pentazolate framework (denoted as MPF-1) is presented. It consists of sodium ions and cyclo-N 5 - anions in which the isolated cyclo-N 5 - anions are preternaturally stabilized in this inorganic open framework featuring two types of nanocages (Na 20 N 60 and Na 24 N 60 ) through strong metal coordination bonds. The compound MPF-1 is indefinitely stable at room temperature and exhibits high thermal stability relative to the reported cyclo-N 5 - salts. This finding offers a new approach to create metal-pentazolate frameworks (MPFs) and enables the future exploration of interesting pentazole chemistry and also related functional materials., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

gem-Dinitromethylated and fluorodinitromethylated 5,5'-dinitro-3,3'-bis-1,2,4-triazole (DNBT) (2 and 3) along with seven ionic derivatives 4-9, were synthesized and characterized by NMR and IR spectroscopies, elemental analysis, single-crystal X-ray diffraction (XRD), and differential scanning calorimetry (DSC). XRD revealed that compounds 2 and 3 crystallized in the monoclinic P2 1 /n space group and compound 5 crystallized in the monoclinic P2 1 /c space group. The physicochemical properties of the as-synthesized compounds 2-9 were investigated and the results indicated that compounds 3, 6, and 7 exhibited a good balance between high energy and low sensitivity, demonstrating their potential as new high-energy-density materials (HEDMs). The proposed synthetic strategy for introducing gem-dinitromethyl and fluorodinitromethyl groups into the DNBT framework to prepare materials with high energy and low sensitivity suitable for HEDMs looks promising., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Over the past few decades, toxic and highly volatile hydrazine derivatives have been the main fuel choices for liquid bipropellants, especially in traditional hypergolic rocket engines. The search for new hypergolic fuels as replacements for hydrazine derivatives is of great interest to researchers. In this study, a series of N-alkylimidazole borane compounds has been synthesized and characterized. Interestingly, these compounds display promising applications as potential hypergolic fuels owing to their excellent physiochemical properties including low melting points, high thermal stability, low viscosities, and unique hypergolic reactivity. Compared with popular hypergolic ionic liquids, the cost-effective and scaling-up advantages of these materials highlight their promising potential as high-performance fuels in liquid bipropellant formulations., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Bis(4-nitraminofurazanyl-3-azoxy)azofurazan (1) and ten of its energetic salts were prepared and fully characterized. Computational analysis based on isochemical shielding surface and trigger bond dissociation enthalpy provide a better understanding of the thermal stabilities for nitramine-furazans. These energetic compounds exhibit good densities, high heats of formation, and excellent detonation velocity and pressure. Some representative compounds, for example, 1 (vD : 9541 m s(-1) ; P: 40.5 GPa), and 4 (vD : 9256 m s(-1) ; P: 38.0 GPa) exhibit excellent detonation performances, which are comparable with current high explosives such as RDX (vD : 8724 m s(-1) ; P: 35.2 GPa) and HMX (vD : 9059 m s(-1) ; P: 39.2 GPa)., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Currently, toxic and volatile hydrazine derivatives are still the main fuel choices for liquid bipropellants, especially in some traditional rocket propulsion systems. Therefore, the search for safer hypergolic fuels as replacements for hydrazine derivatives has been one of the most challenging tasks. In this study, six imidazolylidene-borane compounds with zwitterionic structure have been synthesized and characterized, and their hypergolic reactivity has been studied. As expected, these compounds exhibited fast spontaneous combustion upon contact with white fuming nitric acid (WFNA). Among them, compound 5 showed excellent integrated properties including wide liquid operating range (-70-160 °C), superior loading density (0.99 g cm(-3) ), ultrafast ignition delay times with WFNA (15 ms), and high specific impulse (303.5 s), suggesting promising application potential as safer hypergolic fuels in liquid bipropellant formulations., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To lay a foundation for the study on good variety selection of Isatis indigotica, comparison of plant traits and quality evaluation of Isatis germplasm resources from different production area was conducted., Method: Field cultivation and randomized block experiment were adopted to compare those plant traits of leaf, root, silique and seed of Isatis from different production area and the content of R,S-goitrin and polysaccharide in the root was determined., Result: Different cultivation forms of Isatis had significant difference from each other in leaf, root, silique and seed, content of R,S-goitrin and polysaccharide in the root were also different. R,S-goitrin content in Isatis of Chinese cabbage leaf type ( production area: Yunnan ) was comparative higher, 0.59% , while polysaccharide content in autotetraploid Isatis was comparative higher, 8.68%., Conclusion: According to the plant traits, Isatis were classified into three types: Chinese cabbage leaf type, cabbage leaf type and mustard leaf type, of which R,S-goitrin content in Chinese cabbage leaf type (production area: Yunnan) was comparative higher, while polysaccharide content in autotetraploid Isatis was comparative higher.

Objective: To study the dynamic accumulation of dry matter and index components and provide reference to the manual cultural technique of Pinellia ternata., Method: Seedlings of Taizhou P. ternata were used as the pot experiment material, and the contents of free total organic acid and guanosine of each organ were determined at different stages of spring and autumn period., Result: P. ternata had two growth climax in spring and autumn. Under the same condition of cultivation and management, dry matter largely accumulated in spring. The contents of free total organic acid and guanosine was ascending during the growth period, but dropped during sprout tumble bolting and sprout tumble stage., Conclusion: High temperature and bolting affect the accumulation of organic acids significantly, it is reasonable to prevent the temperature stress in production.

Objective: To study the salt stress tolerance of Hongxinju, Huangju and F1 seedlings from orthogonal and reciprocal cross under different salt treatments. Grope for transmissibility of salt tolerance between parents and F1 seedlings, and relativity between flavone, chlorogenic acid contents and salt tolerance., Method: The materials were put in 5 different concentrations of Hoagland nutrient solution (0, 40, 80, 120, 160 mmol x L(-1)) containing NaCl, keeping grads while raising the consistency of NaCl day by day. The injured leaf area per plant, proline, betaine, MDA, flavones and chlorogenic acid contents were measured and analyzed after treatment., Result: As NaCl concentration was below 120 mmol x L(-1), the salt tolerance of Hongxinju was higher than that of Huangju, the salt tolerance of Hongxinju x Huangju higher than that of parents, the salt tolerance of Huangju x Hongxinju was at the level of parents. As NaCl concentration between 120 to 160 mmol x L(-1), the salt tolerance of Huangju was higher than that of Hongxinju, the salt tolerance of Huangju x Hongxinju higher than that of parents and the salt tolerance of Hongxinju x Huangju was at the level of parents., Conclusion: Salt tolerance of F1 is more influenced by female parent, relativity showed between flavonoids, chlorogenic acid contents and salt tolerance.

Objective: To study the different and the variety of four organic acids in leaves of Isatis indigotica among different cultivated populations in water stress condition and healthy plant., Method: Four kinds of organic acids, such as oxalic acid, malic acid, ascorbic acid and citric acid from the leaves, were detected by HPLC., Result: Significant differences of four organic acids in the leaves of Beijing, Mongolia, Hebei and Shanxi cultivated populations. Compared with the healthy plant, the content of oxalic acid, malic acid and citric acid in water stress were increased, while the content of ascorbic acid was decreased., Conclusion: Contents of four organic acids can act as the guideline factor in I. indigotica because they were related with the water stress condition.

Objective: To study the effect of NH4(+)-N/NO3(-)-N ratios in the applied supplementary fertilizer on the growth, nitrogen metabolis related enzymes activity and photosynthetic characteristics of Isatis indigotica., Method: The sand culture experiment was conducted, and seedling of I. indigotica was fertilized with the mixed nutrition that containing the Hoagland's macro elements and the Aron's micro elements, the additional 63 mmol N was supplementary with the NH4(+)-N/NO3(-)-N ratio of 100:0, 75:25, 50:50, 25:75 and 0:100., Result: The biomass of I. indigotica increased at first when the supplementary N of NH4(+)-N/NO3(-)-N ratio changed from 100:0 to 50:50 and decreased afterwards. The maximum value was at 50:50 and the minimum at 100: 0. With increasing the ratio of NO3(-)-N, the activity of nitrate reductase and glutamine synthetase increased and then decreased and the relationship between the activity and the ratio could be described with an approximate parabola curve. The net photosynthetic rate of I. indigotica was the highest at the NH4(+)-N/NO3(-)-N ratio of 75:25 and the lowest at 100:0., Conclusion: Increasing the NO3(-)-N ratio properly was beneficial to promote the growth and improve the activity of nitrate reductase and glutamine synthetase and net photosynthetic rate of I. indigotica.

Objective: To study the photosynthetic characteristics and chlorophyll fluorescence parameters of Pinellia ternate from different sources, in order to provide basis for cultivation and breeding., Method: Pigment contents were compared among different sources by the Lichtenthaler method. The light-response and diurnal photosynthesis course of P. ternata from different sources were analyzed by LI-6400 system, and chlorophll fluorescence parameters were analyzed by PAM-2100 system., Result: The difference of photosynthetic characteristics among the sources were remarkable. The light compensation point (LCP) of P. ternate from different sources were 11.57-17.88 micromol x m(-2) x s(-1), the light saturation point (LSP) were 1 000-1 300 micromol x m(-2) x (s-1). All the sources have obvious "midday depression". P. ternate cultivated in Xinjiang showed a higher light saturation point (LSP) and better chlorophyll fluorescence parameters., Conclusion: P. ternata cultivated in Xinjiang showed better photosynthetic characteristics and chlorophyll fluorescence parameters than the others.

Objective: To study the effects of four trace elements Mn, Fe, Zn and Cu on growth of the 2nd- and the 3rd-years Paeonia lactiflora., Method: The experiment was designed as randomized blocks. The data of physiological parameters such as fresh weight of root, numbers of bud and root division, length and diameter of the root and the contents of paeoniflorin in root were measured after fertilized with the four trace elements. Also the contents of the four trace elements in soil and roots, stem and leaves of P. lactiflora were detected by atomic absorption spectrometry., Result and Conclusion: The growth of the P. lactiflora was improved and the content of paeoniflorin was increased by proper level of Mn, Fe, Zn and Cu, but depressed by the higher level. Only Zn can be accumulated in the roots of P. lactiflora.