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1.
Inorg Chem ; 62(51): 21371-21378, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38047563

RESUMO

Revamping the structure of energy storage is an efficient strategy for striking a balance between the performance and sensitivity of energetic materials to achieve high energy and reduced sensitivity. In continuation of prior research, this study utilized the ligand 3,5-dimethyl-1H-pyrazole-4-carbonhydrazide (DMPZCA) and innovatively designed and synthesized the compound ECCs [Cu(HDMPZCA)2(ClO4)2](ClO4)2·2H2O (ECCs-1·2H2O). Compared with the former research, solvent-free compound ECCs-1 refers to an innovative material characterized by a dual structure involving ionic salts and coordination compounds. Due to these unique structures, ECCs-1 exhibits an increased [ClO4-] content, a higher oxygen balance constant (OB = -7.9%), and improved mechanical sensitivity (IS = 8 J, FS = 32 N). Theoretical calculations support the superior detonation performance of ECCs-1. Additionally, experimental results confirm its ignition capability through lower-threshold lasers and highlight the outstanding initiation potential and explosive power, making it a suitable candidate for primary explosives.

2.
Dalton Trans ; 52(38): 13716-13723, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37706537

RESUMO

For energetic compounds, their structure determines their performance, and even minor variations in their structure can have a significant impact on their performance. The application scenarios for energetic materials are diverse, and their performance requirements vary as well. To investigate the influence of different substituent positions on the performance of primary explosives, we prepared two Ag(I)-based complexes, [Ag(2-IZCA)ClO4]n (ECPs-1) and [Ag(4-IZCA)ClO4]n (ECPs-2), using structurally isomeric ligands, 1H-imidazole-2-carbohydrazide (2-IZCA) and 1H-imidazole-4-carbohydrazide (4-IZCA). The structures were confirmed using infrared, elemental analysis, and single-crystal X-ray diffraction. Experimental results demonstrate that both ECPs exhibit good thermal stability. However, compared to ECPs-1, ECPs-2 exhibits a lower thermal initial decomposition temperature (Td = 210 °C), lower mechanical sensitivity (IS = 27 J, FS = 84 N), and more concentrated energy output. Although theoretical predictions suggest similar detonation velocities and pressures for both compounds, actual detonation performance tests indicate that ECPs-2 has stronger explosive power and initiating capability, with potential for use as a laser initiator (E = 126 mJ). The simple preparation method and inexpensive starting materials enrich the research on primary explosives.

3.
J Mol Model ; 29(8): 257, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468798

RESUMO

CONTEXT AND RESULTS: 2,4,6-triazide-1,3,5-triazine (TAT) has received widespread attention for its great potential to synthesize or convert to nitrogen-rich high energy density materials (HEDMs). The TAT structure alteration in the compression process up to 30 GPa has characteristics as follows: (a) [N3] groups straighten; (b) [N3] groups gather toward the six-membered C-N heterocycles. At about 5 GPa, Raman peak split at 700 cm-1 was observed both in calculation and in-situ Raman experiment, which is caused by pressure-induced intramolecular stress. Besides, the broad band of the amorphous two-dimensional C=N network (centered at 1630 cm-1) occurred at about 12 GPa. Meantime, the study on electronic features suggests the pressure-induced deformation in TAT molecular structure cause the discontinuous change of band gap at about 4.5 GPa and 8.0 GPa, respectively. COMPUTATIONAL AND THEORETICAL TECHNIQUES: The static compression process of TAT was explored in the range of 0-30 GPa by using dispersion corrected density functional theory (DFT-D) calculations combined with in-situ Raman experiment. The GGA/PBE+G06 method that has less errors than other calculation methods was used to predict the geometry structure, vibrational properties and electronic structure of TAT under pressure.

4.
Inorg Chem ; 62(24): 9695-9701, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37289637

RESUMO

In order to further explore the effect of ligands on the performance of primary explosives and gain a deeper understanding of the coordination mechanism, we designed furan-2-carbohydrazide (FRCA), a ligand, by using oxygen-containing heterocycles and carbohydrazide. Then, FRCA and Cu(ClO4)2 were used to synthesize coordination compounds [Cu(FRCA)2(H2O)(ClO4)2]·CH3OH (ECCs-1·CH3OH) and Cu(FRCA)2(H2O)(ClO4)2 (ECCs-1). The structure of the ECCs-1 was confirmed by single-crystal X-ray diffraction, IR and EA characterization. Further experiments on ECCs-1 show that ECCs-1 has good thermal stability, but is sensitive to mechanical stimuli (impact sensitivity = IS = 8 J, friction sensitivity = FS = 20 N). The predicted value of the detonation parameter is DEXPLO 5 = 6.6 km s-1, PEXPLO 5 = 18.8 GPa, but the ignition test, laser test, and lead plate detonation experiment show that ECCs-1 has excellent detonation performance, which is very worthy of attention.

5.
Langmuir ; 39(26): 9239-9245, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37356112

RESUMO

In order to preserve the coordinating ability of the hydrazide group, we used retrosynthetic analysis to design and synthesize ligand furan-2,5-dicarbohydrazide and its complex [Cu(FDCA)(H2O)ClO4]n(ClO4)n·nH2O (ECPs-1·H2O). The structure of the product was confirmed by single-crystal X-ray diffraction, infrared spectroscopy, and elemental analysis. The solvent-free target material ECPs-1 exhibited good thermal stability, sensitivity to mechanical stimuli, and excellent explosive properties. Furthermore, it had good potential for laser ignition and comparable detonation power to LA. The simple preparation method and inexpensive starting materials enriched the research on primary explosives.

6.
FEBS Lett ; 589(3): 285-94, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25535697

RESUMO

We reconstructed the first genome-scale metabolic network of the plant pathogen Pectobacterium carotovorum subsp. carotovorum PC1 based on its genomic sequence, annotation, and physiological data. Metabolic characteristics were analyzed using flux balance analysis (FBA), and the results were afterwards validated by phenotype microarray (PM) experiments. The reconstructed genome-scale metabolic model, iPC1209, contains 2235 reactions, 1113 metabolites and 1209 genes. We identified 19 potential bactericide targets through a comprehensive in silico gene-deletion study. Next, we performed virtual screening to identify candidate inhibitors for an important potential drug target, alkaline phosphatase, and experimentally verified that three lead compounds were able to inhibit both bacterial cell viability and the activity of alkaline phosphatase in vitro. This study illustrates a new strategy for the discovery of agricultural bactericides.


Assuntos
Genoma Bacteriano , Redes e Vias Metabólicas , Pectobacterium carotovorum/isolamento & purificação , Pectobacterium carotovorum/metabolismo , Simulação por Computador , Anotação de Sequência Molecular , Pectobacterium carotovorum/genética , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Plantas/microbiologia
7.
Cytotherapy ; 14(4): 483-93, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22277010

RESUMO

BACKGROUND AIMS: The aim of this study was to evaluate the efficacy and safety of cytokine-induced killer (CIK) cell therapy for solid carcinomas. METHODS: We performed a computerized search of phase II/III clinical trial databases of CIK cell-based therapy using a combination of the terms 'cytokine-induced killer cells', 'tumor' and 'cancer'. RESULTS: Treatment with CIK cells was associated with a significantly improved half-year survival (P = 0.003), 1-year survival (P = 0.0005), 2-year survival (P < 0.01) and mean survival time (MST) (P < 0.001). Patients in the CIK group showed a prolonged half-year progression-free survival (PFS) (P < 0.01), 1-year PFS (P < 0.01) and median time to progression (MTTP) (P < 0.001). A favored disease control rate (DCR) was observed in patients receiving CIK cell therapy, while the objective response rate (ORR) was not altered (P = 0.05) compared with the non-CIK group (P = 0.007). CIK cell therapy could also reduce the adverse effects of grade III and IV leukopenia caused by chemotherapy (P = 0.002) and diminish hepatitis B virus (HBV)-DNA content (P < 0.01). However, the incidence of fever in the CIK therapy group was significantly higher than in the non-CIK group (P = 0.02). The percentage of CD3(+), CD4(+), CD4(+)CD8(+), CD3(-) CD56(+) and CD3(+) CD56(+) T-lymphocyte subsets in the peripheral blood of cancer patients was significantly increased, whereas the percentage of CD8(+) T-lymphocyte cells was significantly decreased in the CIK group compared with the non-CIK group (P < 0.01). CONCLUSIONS: CIK cell therapy has demonstrated a significant superiority in prolonging the MST, PFS, DCR and quality of life (QoL) of patients.


Assuntos
Carcinoma/terapia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Matadoras Induzidas por Citocinas/citologia , Células Matadoras Induzidas por Citocinas/transplante , Humanos
8.
Zhonghua Nan Ke Xue ; 17(10): 905-8, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22049794

RESUMO

OBJECTIVE: To evaluate the feasibility and safety of the modified urethral pull-through procedure for the treatment of posterior urethral stricture or atresia. METHODS: We retrospectively analyzed 212 cases of posterior urethral stricture or atresia treated by the modified urethral pull-through procedure. The length of the stricture or atresia was 1.5 - 12 cm, and 66 cases had experienced 1 - 4 previous unsuccessful urethral repairs. Simple transperineal approach was adopted in 208 cases and transperineal-inferiorpubic approach in the other 4. And 15 of the patients underwent urethral construction with grafts. RESULTS: Satisfactory voiding was achieved in 198 (93.4%) of the patients, of whom 16 received 3 - 15 urethral dilations. Of the 14 cases that failed, 10 succeeded after a second and 2 after a third operation. Of the 15 cases that underwent substitution urethroplasty, 14 achieved satisfactory voiding, and only 1 needed repeat dilation. No serious complications were observed in any of the patients. CONCLUSION: Modified urethral pull-through procedure, with its advantages of safety, mini-invasiveness, simple operation and high success rate, is feasible for the treatment of posterior urethral stricture or atresia, while for that with the length >5 cm, substitution urethroplasty should be considered.


Assuntos
Uretra/cirurgia , Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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