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Controlling the selectivity of a detonation initiation reaction of explosive is essential to reduce sensitivity, and it seems impossible to reduce it by strengthening the external electric field. To verify this, the effects of external electric fields on the initiation reactions in NH2NO2∙∙∙NH3, a model system of the nitroamine explosive with alkaline additive, were investigated at the MP2/6-311++G(2d,p) and CCSD(T)/6-311++G(2d,p) levels. The concerted effect in the intermolecular hydrogen exchange is characterized by an index of the imaginary vibrations. Due to the weakened concerted effects by the electric field along the −x-direction opposite to the "reaction axis", the dominant reaction changes from the intermolecular hydrogen exchange to 1,3-intramolecular hydrogen transference with the increase in the field strengths. Furthermore, the stronger the field strengths, the higher the barrier heights become, indicating the lower sensitivities. Therefore, by increasing the field strength and adjusting the orientation between the field and "reaction axis", not only can the reaction selectivity be controlled, but the sensitivity can also be reduced, in particular under a super-strong field. Thus, a traditional concept, in which the explosive is dangerous under the super-strong external electric field, is theoretically broken. Compared to the neutral medium, a low sensitivity of the explosive with alkaline can be achieved under the stronger field. Employing atoms in molecules, reduced density gradient, and surface electrostatic potentials, the origin of the reaction selectivity and sensitivity change is revealed. This work provides a new idea for the technical improvement regarding adding the external electric field into the explosive system. [ABSTRACT FROM AUTHOR]

A novel method for synthesizing carfentanil is researched in this work. N-Boc-protected piperidinone was used as the starting material. The carfentanil was achieved via synthetic rout involving five steps: Bargellini reaction, N-acylation, methylation, deprotection and N-alkylation. The overall yield of target compound was 31. 6%. The structures of intermediates and final product were determined by infrared spectroscopy, nuclear magnetic resonance spectroscopy and mass spectrograph. [ABSTRACT FROM AUTHOR]

This paper studies two-step synthetic process of TEX (4,10-dinitro-2,6, 8,12-tetraoxa-4, 10-diazatetracyclo-[5. 5. 0. 05,9 03,11]-dodecane) and the effects of key factors on the yield of DFTHP (intermediate) and TEX. The results show that the yield of DFTHP could reach to 68. 3% when the adjusted pH value of reaction solution reaches to 9 by saturated NaOH solution. When the volume ratio of fuming HNO3 to concentrated H2SO4 is 3 : 2, and the ratio of nitrating agent (mL) to DFTHP(g) is 3 : 1, the yield of TEX raises to 59. 7% . The optimized overall yield of TEX obtained from two-step synthetic process could be 40. 8%. [ABSTRACT FROM AUTHOR]

Dinitro pentamethylene tetramine (DPT) is an important precursor of octogen (cyclotetramethylene tetramine, HMX). This article explores the process of synthesizing DPT by one-pot method to provide a practical basis for improving HMX production through DPT. The urea was used as the original material. Without isolation from intermediates, DPT was obtained by the chemical reaction of nitration, hydrolysis and Mannich condensation. Some factors to affect yield of DPT were investigated, such as dosage of nitric acid, nitration time, hydrolyzation time, dosage of formaldehyde, pH of solution and so on. The optimum conditions of process were determined. With this process, the yield of DPT was advanced up to 65.2%. [ABSTRACT FROM AUTHOR]

The simple protocol allows the direct amination of acetophenone and benzophenone bearing a p-chloro substituent with cyclic secondary amines. [ABSTRACT FROM AUTHOR]

Objective: To study the clinical application value of middle segment pancreatectomy in the treatment of benign tumors of the amphi-neck of the pancreas., Methods: Fifteen cases were retrospectively analyzed treated from November 2005 to June 2009. There were 3 male and 12 female aging from 30 to 50 years. They all received middle segment pancreatectomy for benign tumors of the amphi-neck of the pancreas., Results: There was no death during perioperative period. All the 15 patients received middle segment pancreatectomy. Fourteen of them received the closure of broken ends of pancreatic head, pancreaticojejunostomy (mono-anastomosis) and the rest one received dipl-anastomosis. Postoperative pathology showed that in the 15 patients, 1 got solid-pseudopapillary tumor of the pancreas, 3 got non-functional islet cell tumor, 11 got cystadenoma of pancreas. Three of them got pancreatic fistula and were self cured in 3 months. Follow-up visits to all the patients kept in the following 2 to 45 months. There was no death. No patients got new-onset diabetes and pancreatic pseudocyst. And their tumors were not relapsed., Conclusions: There is an exact therapeutic effect of middle segment pancreatectomy for benign tumors of the amphi-neck of the pancreas. The treatment has little function damage to patients' endocrine and external secretion. The incidence rate of pancreatic fistula in middle segment pancreatectomy is higher than that in pancreaticoduodenectomy. As long as the drainage is kept unobstructed, most of the pancreatic fistula can be self cured.

Objective: To study the selective effect to tumor cells mediated by a recombinant adenoviral vector carrying E2F-1 promoter., Methods: The AdEasy-1 adenoviral vector system was used in this experiment. Several recombinant adenovirus with tumor-targeting E2F-1 promoter were constructed and then the E2F-1 promoter gene was checked by PCR and sequencing. The two adenovirus expressing GFP gene which is regulated by E2F-1 promoter or CMV promoter were used to respectively transfect tumor cells and non-proliferating normal cells, then observed and analyzed the different results caused by different promoters. Vpr gene was cloned into the targeting recombinant adenovirus. The new adenovirus named rvAdE2F-1/vpr was used to transfect tumor cells SMMC-7721, LS174T and non-proliferating normal cells H292, L-02. The surviving rate of each group was registered; the level of E2F-1 protein expressed in normal and tumor cell lines were checked by Western Blot., Result: E2F-1 promoter can regulate the downstream gene GFP selectively expressed in LS174T and its activity in LS174T was similar with CMV promoter's; Vpr gene regulated by E2F-1 promoter can suppress the proliferation of tumor cells and no toxicity to normal cells; In all of the tumor cells, a much higher level of E2F-1 was expressed compared with normal cell lines. E2F-1 promoter's activity correlated well with E2F-1 protein levels., Conclusions: E2F-1 promoter can control a selective cell killing to cancer cells, with no effect to normal cells. The system of E2F-1 promoter is a useful method for tumor-targeting gene therapy.