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Photonic glasses with infrared gaps can be used as surface coating materials to effectively change the infrared radiation characteristics of substrate. In this research, a photonic glass with an infrared broad gap could be prepared easily in thermostatic water bath by a simple and fast baking protocol. The photonic glass prepared had a broad gap from 4.25 to 4.57 μm, centering at 4.45 μm, which was slightly different from the result of numerical simulation due to the existence of the internal disordered structure. The infrared transmission diagram showed that the infrared transmittance of a substrate covered by the photonic glass can be reduced from 80 % to 25 % at infrared atmosphere window of 3∼5 μm, which proved the ability of the material to regulate and control the infrared electromagnetic wave. In addition, the material can significantly restrain the infrared radiation of the substrate at 60 °C, which was expected to achieve stealth under the infrared detection. [ABSTRACT FROM AUTHOR]

Istradefylline is a selective adenosine antagonist for A2a receptor, and it is used to treat Parkinson's syndrome and improve dyskinesia in the early stage of Parkinson's disease. Istradefylline aqueous solution were preserved in darkness and light respectively, and it was found that Istradefylline aqueous solution were extremely unstable in light. An impurity of Istradefylline was identified by HPLC and further collected by preparative HPLC. The impurity was characterized by NMR and MS and identified as Z‐Istradefylline, a photo degradation product of Istradefylline. The founding of degradation phenomenon makes the research on the stability of Istradefylline aqueous solution absolutely necessary for the quality control of the drug. [ABSTRACT FROM AUTHOR]

The application of fluorescent method to metal ions detection features high sensitivity, simple operation and real‐time monitoring. A 2,7‐dihydroxynaphthalene‐functionalized dimethyl glycoluril (called clip 1) was synthesized, using a relatively simple method. And it is fully characterized by 1H NMR, 13C NMR, HR‐MS and single crystal X‐ray diffraction. The recognition properties of molecular clip 1 were analyzed systematically toward several metal ions using fluorescence spectroscopy, and it was found that molecular clip 1 is selective and sensitive to Fe3+. At the same time, the clip 1 shows good anti‐interference ability when other metal ions existed. The limit detection of Fe3+ is 3×10−7M. The fluorescence of clip 1 was quenched apparently by Fe3+, which was speculated to be caused by ligand–metal charge transfer mechanism (LMCT). As a new fluorescence probe for Fe3+ ion, it may expanded the application of glycoluril molecular clips. [ABSTRACT FROM AUTHOR]

Self‐monitoring of blood glucose is not only an effective method to treat diabetes, but also a painful invasive process to patients. To develop a noninvasive technique, we evaluated the clinical performance of a polymerized crystalline colloidal array (PCCA) sensor for glucose monitoring in urine. A two‐dimensional crystalline colloidal array (CCA) was assembled using polystyrene particles and further embedded into 3‐acrylamidophenylboronic acid functionalized hydrogel. 101 urine samples were tested, and the glucose concentrations was calculated by the particle spacing of PCCA. All the urine samples were also analyzed by automated urine analyzers. Pearson correlation and linear regression analyses showed a linear relationship between the PCCA results with a range of 0.4‐53.3 mmol L−1 and the Cobas® 8000 references (r=0.914; [PCCA]=0.9281 [HK] + 2.0585 mmol L−1). Cohen's kappa (κ) statistic with 0.65 (sig < 0.05) showed the PCCA results had moderate agreement with references. Also, Bland‐Altman plot showed that AX‐4030 sensor's systematic error was higher than PCCA sensor (mean=7.4813 > 0.5271 mmol L−1). The PCCA urine glucose biosensor has the advantages of fast fabrication, low cost, easy operation and high sensitivity, which provides a promising technique for noninvasive point‐of‐care glucose monitoring. [ABSTRACT FROM AUTHOR]

A novel synthetic method of the 1, 3, 5‐trinitro‐2, 2‐bis(trifluoromethyl)‐1,3,5‐triazinane (2) has been successfully developed. In addition to IR, 1H 13C NMR and elemental analysis, compound 2 was characterized by 15N NMR and X‐ray single crystal diffraction. Due to the introduction of trifluoromethyl, the density of compound 2 is up to 2.04 g⋅cm−3 at 298 K, which is consistent with its crystal density (2.059 g⋅cm−3, 296(2) K). Compound 2 exhibits excellent detonation pressures and velocities (P, 45.6 GPa; vD, 9564 m⋅s−1), as good as exceptional impact and friction sensitivities(IS, 22.5 J; FS, >360 J). Some of these values are better than the current benchmark explosives, such as 1, 3, 5‐trinitrodihydro‐1, 3, 5‐triazine (RDX) and cyclo‐1, 3, 5, 7‐tetramethylenene‐2, 4, 6, 8‐tetranitramine (HMX).It is a potential high energy density material. [ABSTRACT FROM AUTHOR]

A new glycoluril derivative‐1H, 4H, 5H, 8H‐2, 3a, 4a, 6, 7a, 8a‐hexaazacyclopenta[def]fluorene‐4, 8‐dione, hexahydro‐2, 6‐bis(phenylmethyl) (3) is strategically designed and synthesized through the reaction between glycoluril, formaldehyde and benzylamine with the optimized molar ratio of 1:6:2. Compound 3 is fully characterized by 1H NMR, 13C NMR, IR, MS and X‐ray single crystal diffraction. Reduction of compound 3 delivers a potential precursor‐imidazo[4, 5‐d]imidazole, octahydro‐hexahydro‐2, 6‐bis(phenylmethyl) (4) for the synthesis of novel nitramine explosives (i.e. bicyclo‐HMX and bi‐RDX). The nitration and hydrolysis of compound 4 are investigated in detail and three ring‐opened molecules N, 2, 4‐trinitro‐benzenemethanamine (8a), N, 2‐dinitro‐benzenemethanamine (8b) and N‐methylene‐benzenemethanamine (9) are obtained. The synthesis, X‐ray crystal structure, hydrolysis, nitrolysis of two potential precursors for the preparation of nitramine explosives (bicycle‐HMX and bi‐RDX) are reported. [ABSTRACT FROM AUTHOR]

Based on the advantages of the furazan and tetrazole ring, the nitro and N‐oxide groups were introduced into furazan‐tetrazole backbone to four kinds of novel nitrofurazan‐functionalized hydroxytetrazole energetic salts. Various method have been employed to confirm their structures, such as multinuclear NMR, FTIR spectroscopy and elemental analysis. Salt guanidinium 5‐(4‐nitro‐furazan‐3‐yl)‐tetrazole‐1‐olate (5) and salt potassium 5‐(4‐hydroxyamino‐furazan‐3‐yl)‐tetrazole‐1‐olate (6) has been further elucidated by single‐crystal X‐ray diffraction. The non‐isothermal decomposition kinetics and thermodynamics for different salts were investigated by using TG‐DSC with different heating rate. The physico‐chemical properties and detonation performance were also studied and calculated by EXPLO5 program, in which salt hydroxylammonium 5‐(4‐nitro‐furazan‐3‐yl)‐tetrazole‐1‐olate (3) have a relatively high density of 1.839 g⋅cm−3 at 296 K and good detonation properties (vD = 9228 m⋅s‐1, P = 38.0 GPa), which is superior to that of RDX. The sensitivities towards impact and friction were also determined by BAM method (BAM Fallhammer Test for IS; BAM Friction Test for FS), in which the salt 5 showed very insensitive property (IS>60 J, FS>360 N) and can be comparable to that of TATB. Furthermore, the specific impulse of salt 3 (281 s) was even better than that of ammonium perchlorate (AP) (157 s) as neat compounds. The nitro group and N‐oxide groups were introduced into furazan‐tetrazole backbone to synthesize a series of novel nitrofurazan‐functionalized hydroxytetrazole energetic salts, where salt 3 exhibited a good detonation performance and moderate sensitivity. [ABSTRACT FROM AUTHOR]

Energetic salts readily exhibited desirable properties through appropriate combination of different cations and anions. Due to its acidity of nitramine group, 1,1,2,2‐tetranitroaminoethane (TNAE) is a good anion in energetic salts. In this paper, diaminoguanidine and hydroxylamine salts of TNAE have been synthesized and their performances were studied. Both salts of TNAE exhibit excellent detonation pressure and velocity based on theoretical performance calculation. Especially, the diaminoguanidine salt of TNAE exhibits excellent thermal stability and insensitive to impaction and friction. It will has a great potential to be applied in the field of energetic materials. TNAE is a typical energy material, which can be used as a good anion in energetic salts. Two new energetic salts of TNAE have been synthesized and fully characterized. Both salts of TNAE showed excellent explosive performance, thermal stability and insensitive to impaction. Especially, the diaminoguanidine salt of TNAE exhibits excellent insensitive to impact and friction, which has a great potential in applications. [ABSTRACT FROM AUTHOR]