膨化硝酸铵自敏化理论研究

膨化硝酸铵自敏化理论是膨化技术发明的核心,它是基于热点理论把微气泡植入硝酸铵炸药中。微气泡临界热点温度热力学计算为自敏化提供理论依据。与普通硝酸铵及珍珠岩相比较,微气泡在膨化硝酸铵内适当的分布为自敏化成功提供了有力的保证。     

硝酸铵膨化技术及应用

硝酸铵膨化技术是一创新技术,创新设计的指导思想是硝酸铵自敏化,硝酸铵自敏化的提出是对国内外传统方法的突破。实施自敏化的技术途径是硝酸铵的膨化,其实质是表面活性技术在粉状炸药中的应用,是一个强制析晶的物理化学过程。文章重点讨论了硝酸铵膨化机理及膨化硝酸铵的技术特征,显示其独特的优点。硝酸铵膨化技术主要应用是岩石膨化硝铵炸药,给出了岩石膨化硝铵炸药的爆炸与物理特征数据,并与其它工业炸药做了比较。同时也推广应用在煤矿许用型炸药中。     

硝酸铵自敏化的基本原理和技术途径

低成本和优性能的无梯粉状硝铵炸药是工业炸药发展的趋势之一，其中硝酸铵自敏化是关键的技术途径。文中基于爆炸理论和化学原理，对硝酸铵自敏化的可能途径进行了分析和论述，主要有微气泡自敏化、晶格缺陷自敏化、晶变自敏化、晶体活化敏化和表面自敏化等。     

膨化硝酸铵自敏化理论基础与实验研究

膨化硝酸铵自敏化理论是基于热点学说,在广泛研究敏化手段情况下,它是对国内外传统方法的突破,它把微气泡通过膨化技术植入膨化硝铵炸药中,达到自敏化创新设计。实验研究了膨化硝酸铵晶体、结构、微气泡分布等,对自敏化理论设计成功给予进一步证实。     

膨化硝酸铵的微观结构研究

文章对膨化硝酸铵、普通硝酸铵进行晶形电镜扫描,研究了其孔径与孔容分布、粒径分布、比表面积测定及DSC实验,揭示了膨化硝酸铵的微观结构,说明了膨化硝酸铵具备自敏化的结构特征.     

气流工艺生产岩石型硝酸铵炸药可行性探讨

文章采用控制硝酸铵水分使硝酸铵微粉化,加添加剂使硝酸铵改性活化,喷油雾化使组化混合幸均匀,本粉吸收硝酸铵微粉和油后变成炸药单体颗粒起敏化作用等一系列技术,可用气流工艺直接生产硝酸铵炸药.     

全自动粉状硝铵炸药生产技术的分析和设计

通过对硝酸铵敏化机理的研究,探求无梯硝铵炸药影响敏化的主要因素,以及无梯硝铵炸药选择硝铵改性进行敏化的可行路线,介绍了全自动粉状硝铵炸药自动化连续化工业生产的工艺过程。     

测试密度对膨化硝酸铵微观结构表征的影响

文章利用NOVA1000比表面积测试仪,测试了膨化硝酸铵在堆积密度和晶体密度下的孔径分布、累积孔面积和累积孔体积、比表面积以及孔容等微观结构参数,并比较了两种密度下表征膨化硝酸铵的微观结构参数的差异.结合理论分析和测试数据可知,利用硝酸铵的晶体密度进行测试可以更精确地表征膨化硝酸铵的微观结构,避免了因测试堆积密度而导致的测试误差,能够更好地理解硝酸铵的自敏化理论.     

几种高分子乳化剂在乳化炸药中的性能研究

选取几种不同性能指标的聚异丁烯丁二酰亚胺类高分子乳化剂,通过低剪切乳化、低浓度乳化(乳化剂质量占基质比:0.1%)测试了乳化剂的乳化能力;按照现场散装乳化炸药配方制备了乳化基质,通过动力黏度、自然储存、高低温循环、超声波法等评价了基质的基本性能,测定了乳化炸药的敏化速率和初始爆速。结果表明:EMU-3高分子乳化剂制备的乳化基质储存稳定性和抗颠簸性能好,基质黏度适中,敏化速率适宜,炸药爆速达4 436 m/s,适宜于现场散装乳化炸药的生产。     

几种高分子乳化剂在乳化炸药中的性能研究

选取几种不同性能指标的聚异丁烯丁二酰亚胺类高分子乳化剂,通过低剪切乳化、低浓度乳化(乳化剂质量占基质比:0.1%)测试了乳化剂的乳化能力;按照现场散装乳化炸药配方制备了乳化基质,通过动力黏度、自然储存、高低温循环、超声波法等评价了基质的基本性能,测定了乳化炸药的敏化速率和初始爆速。结果表明:EMU-3高分子乳化剂制备的乳化基质储存稳定性和抗颠簸性能好,基质黏度适中,敏化速率适宜,炸药爆速达4 436 m/s,适宜于现场散装乳化炸药的生产。     

超声制备微乳化柴油的实验研究

微乳柴油是一种较佳的节能环保材料。采用聚氧乙烯失水山梨醇单油酸酯(Tween80)、失水山梨醇单油酸酯(Span80)和十二烷基苯磺酸钠复配成复配乳化剂,利用超声乳化机理,将超声波用于微乳化,研究了超声参数(声强,作用时间)、乳化剂及乙醇用量对乳液稳定性的影响,并通过正交实验找出了超声制备微乳化柴油的最佳工艺条件。该W/O乳液稳定时间随超声声强的增大而增加,且超声作用时间对乳液稳定时间有个最佳值。超声作用下乳化剂用量为2.5%(wt)时乳液最稳定。乙醇用量跟水油比有关,实验中水油比为0.1(V)时乙醇用量为5%(V),掺水量为10%(V)时的超声柴油微乳化最佳工艺条件为乳化剂用量为2.5%(wt),指示电流为3A(相当于声强为0.15 W/cm2),稳定剂用量为0.158%(wt),超声作用时间为15min,乙醇用量为5%(V)。     

一级乳化工艺制备长储存期乳化炸药的试验研究

研究了一级乳化工艺条件下,乳化剂种类、油相配方及不同乳化器对乳化炸药爆炸性能和储存稳定性的影响,采用高低温循环试验考察制备乳化炸药的储存稳定性。试验研究表明:一级乳化(CYJ型乳化器)时,LZ27011乳化剂制备的乳化炸药储存稳定性、爆炸性能和微观结构均优于S/T乳化剂制备的乳化炸药;乳化剂为LZ27011时,CYJ型乳化器较JWL-YR乳化器的乳化效果更好;乳化剂(Span80和LZ27011的质量比为0.51.5)和乳化器确定时,油相配比对乳化炸药的储存稳定性有显著的影响,当油相组成复合蜡和150SN的质量比为3.21.0时,所制得的乳化炸药经34个高低温循环后,爆炸性能仍符合标准要求。     

In vitro release properties of caffeine. I. effect of concentration and type of ointment base

Caffeine has recently been found to cure atopic dermatitis, presumably by increasing skin levels of cAMP.In the light of these findings, its release from different ointment bases at varying concentrations was investigated in vitro. The ointment bases used were a petrolatum (named as petrolatum A), a PEG ointment (USP XVIII), a hydrophilic ointment (USP XVIII), and a w/o type emulsifying ointment. It was incorporated into ointment bases at 1,5,10,20 and 30% (w/w) concentrations, by simple trituration technique.

Release experiments were carried out at 37°C, with diffusion cells which were placed in distilled water filled beakers.

For all caffeine concentrations used, the release was highest from the PEG ointment. It decreased with the hydrophilic ointment, the emulsifying ointment, and petrolatum A, in that order. From both petrolatum base and the PEG ointment, release of caffeine increased significantly with increasing concentrations. As for the hydrophilic and emulsifying ointments, release patterns were found to be independent of concentration for some percentages of caffeine.     

Preparation of MoS2‐Coated Three‐Dimensional Graphene Networks for High‐Performance Anode Material in Lithium‐Ion Batteries

A novel composite, MoS₂‐coated three‐dimensional graphene network (3DGN), referred to as MoS₂/3DGN, is synthesized by a facile CVD method. The 3DGN, composed of interconnected graphene sheets, not only serves as template for the deposition of MoS₂, but also provides good electrical contact between the current collector and deposited MoS₂. As a proof of concept, the MoS₂/3DGN composite, used as an anode material for lithium‐ion batteries, shows excellent electrochemical performance, which exhibits reversible capacities of 877 and 665 mAh g^?1 during the 50^th cycle at current densities of 100 and 500 mA g^?1, respectively, indicating its good cycling performance. Furthermore, the MoS₂/3DGN composite also shows excellent high‐current‐density performance, e.g., depicts a 10^th‐cycle capacity of 466 mAh g^?1 at a high current density of 4 A g^?1.     

丁二酰亚胺乳化机理的探讨

文中讨论了用于制备乳化炸药的丁二酰亚胺的乳化机理，根据丁二酰亚胺的分子结构，认为油溶性丁二酰亚胺作为油相和水相的媒介，与水之间除存生物在物理吸附之外，还存在以氢键为主的化学吸附，从而能显著地降低油水两相界面张力，构成稳定的乳胶颗粒。     

In vitro release properties of caffeine. I. effect of concentration and type of ointment base

Abstract

Caffeine has recently been found to cure atopic dermatitis, presumably by increasing skin levels of cAMP.In the light of these findings, its release from different ointment bases at varying concentrations was investigated in vitro. The ointment bases used were a petrolatum (named as petrolatum A), a PEG ointment (USP XVIII), a hydrophilic ointment (USP XVIII), and a w/o type emulsifying ointment. It was incorporated into ointment bases at 1,5,10,20 and 30% (w/w) concentrations, by simple trituration technique.

Release experiments were carried out at 37°C, with diffusion cells which were placed in distilled water filled beakers.

For all caffeine concentrations used, the release was highest from the PEG ointment. It decreased with the hydrophilic ointment, the emulsifying ointment, and petrolatum A, in that order. From both petrolatum base and the PEG ointment, release of caffeine increased significantly with increasing concentrations. As for the hydrophilic and emulsifying ointments, release patterns were found to be independent of concentration for some percentages of caffeine.     

Formulation and efficacy studies of new topical anesthetic creams

Local anesthetics (lidocaine or tetracaine) spontaneously melted at 25°C when mixed with thymol and aqueous isopropyl alcohol solution (IPA) at proper ratios and formed novel two-phase melt systems (TMS). The TMS consisted of a homogeneous oil phase containing primarily a local anesthetic agent (lidocaine or tetracaine) and thymol, and a homogeneous aqueous phase containing primarily IPA and pH 9.2 buffer. The relationship between melting of the solid components and system composition was determined from the phase diagram obtained by a titration method. A select TMS of a local anesthetic agent (lidocaine or tetracaine) was directly emulsified to prepare an O/W cream and tested for the anesthetic efficacy on intact human skin. While both lidocaine (6%) and tetracaine (4%) creams were highly effective for dermal anesthesia with a similar onset time, the tetracaine cream exhibited a significantly longer duration of action than the lidocaine cream. An accelerated stability study indicated that lidocaine was significantly more stable than tetracaine in the creams.     

Oral bioavailability enhancement of acyclovir by self-microemulsifying drug delivery systems (SMEDDS)

Acyclovir is a potent anti-viral agent useful in the treatment of Herpes Simplex Virus (HSV) infections. Acyclovir exerts its antiviral activity by competitive inhibition of viral DNA through selective binding of acyclovir to HSV-thymidine kinase. The main purpose of this work was to develop self-microemulsifying drug delivery system (SMEDDS) for oral bioavailability enhancement of acyclovir. Solubility of acyclovir was determined in various vehicles. SMEDDS is mixture of oils, surfactants, and co-surfactants, which are emulsified in aqueous media under conditions of gentle agitation and digestive motility that would be encountered in the gastro-intestinal (GI) tract. Pseudoternary phase diagrams were constructed to identify the efficient self-emulsifying region dilution study was also performed for optimization of formulation. SMEDDS was evaluated for its percentage transmittance, Assay of SMEDDS, phase separation study, droplet size analysis, zeta potential, electrophoretic mobility, and viscosity. The developed SMEDDS formulation contained acyclovir (50 mg), Tween 60 (60%), glycerol (30%) and sunflower oil (9%) was compared with the pure drug solution by oral administrating to male albino rats. The absorption of acyclovir from SMEDDS form resulted about 3.5 fold increase in bioavailability compared with the pure drug solution. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds such as acyclovir by oral route.     

Oral Bioavailability Enhancement of Acyclovir by Self-Microemulsifying Drug Delivery Systems (SMEDDS)

Acyclovir is a potent anti-viral agent useful in the treatment of Herpes Simplex Virus (HSV) infections. Acyclovir exerts its antiviral activity by competitive inhibition of viral DNA through selective binding of acyclovir to HSV-thymidine kinase. The main purpose of this work was to develop self-microemulsifying drug delivery system (SMEDDS) for oral bioavailability enhancement of acyclovir. Solubility of acyclovir was determined in various vehicles. SMEDDS is mixture of oils, surfactants, and co-surfactants, which are emulsified in aqueous media under conditions of gentle agitation and digestive motility that would be encountered in the gastro-intestinal (GI) tract. Pseudoternary phase diagrams were constructed to identify the efficient self-emulsifying region dilution study was also performed for optimization of formulation. SMEDDS was evaluated for its percentage transmittance, Assay of SMEDDS, phase separation study, droplet size analysis, zeta potential, electrophoretic mobility, and viscosity. The developed SMEDDS formulation contained acyclovir (50 mg), Tween 60 (60%), glycerol (30%) and sunflower oil (9%) was compared with the pure drug solution by oral administrating to male albino rats. The absorption of acyclovir from SMEDDS form resulted about 3.5 fold increase in bioavailability compared with the pure drug solution. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds such as acyclovir by oral route.     

乳化剂理论及其选择研究

文章阐述了乳化炸药中乳化工艺及乳化剂作用的物理化学原理。基于对乳化剂的实验研究，为有效乳化和长贮安定，对乳化剂的选择提出几点看法，特别讨论了混合乳化剂的重要意义。