Construction of a novel ZnO/rGO hybrid composite for efficient degradation of CV,Cr (VI) and 2, 4-D under visible light irradiation

The pristine ZnO and ZnO-Graphene hybrid composites at various graphene ratios were synthesized via facile ultrasonic assisted solution approach. The crystal structure is identified by powder XRD technique and disclosed the hexagonal wurtzite structure. The synthesized ZnO exhibited uniform spherical like morphology with low degree of aggregation. The formation of hybrid composite of graphene and ZnO could improve the light absorption ability and separation of photo generated carriers of ZnO, which is confirmed through photoluminescence and UV–Vis DRS analysis. The photo catalytic degradation of Crystal violet, Cr (VI) and 2, 4 D were evaluated under visible light irradiation. The Zn-Graphene hybrid composite exhibited higher photo catalytic activity towards CV dye, Cr (VI) and 2, 4-D, such as high photo degradation efficiency and good stability than bare ZnO. This could be due to the high surface area and synergic effect between the graphene and ZnO p–n junctions. The mechanism of enhanced photo catalytic activity of Zn-Graphene composite discussed in detail.     

Vacuum-UV-photolysis of aqueous solutions of citric and gallic acids

The vacuum-UV- (VUV-) photolysis of water is one of the advanced oxidation processes (AOP) based on the production of hydroxyl radicals (HO) that can be applied to the degradation of organic pollutants in aqueous systems. The kinetics of the VUV-photolyses of aqueous solutions of citric acid (1) or gallic acid (2) were investigated in the presence or absence of dissolved molecular oxygen (O₂) and under different pH conditions. In the case of 1, the rate of consumption of the substrate was faster at pH 3.4 than in alkaline solution (pH 11), whereas, in the case of 2, the variation of pH (2.5–7.5) did not affect the course of the reaction. Unexpectedly, the rates of depletion of both 1 and 2 decreased in the absence of O₂, this effect being much more pronounced in the case of 2. In order to explain these results, possible reaction pathways for the degradation of 1 and 2 are proposed, and the roles of the oxidizing (HO) and reducing (H and e_aq⁻) species produced by the VUV-photolysis of water are discussed.     

Design and implementation of DBC based on dynamic AOP

Traditional approach of design by contract, due to mixing the contract code with application code, is difficult for the extensibility and reusability of software system. This paper presents a framework named JADBC for design by contract based on Aspect-Oriented Programming (AOP) to resolve these problems. By providing a new modularized element, aspect, the framework successfully separates the contracts in design by contract, from functional codes. The implementation of this framework is based on dynamic AOP which can have the contract changed at runtime, consequently, enhancing program flexibility. JADBC framework modularizes the contracts in a clear-cut fashion that is easier to design, implement, and maintain. Biography: WEN Jing (1982–), female, Ph.D. candidate, research directions: software engineer, aspect-oriented software development.     

细粒度角色访问控制模型及其应用

针对传统的角色访问控制模型权限控制粒度较大、权限控制代码横切业务功能模块、难以有效支持软件复用等问题．提出了一种细粒度角色访问控制模型。该模型通过引入外权限和内权限细化了权限控制粒度．并通过AOP技术实现了内权限的动态配置,提高了组件复用度和模块独立性。该模型已在实际项目中得到应用,验证了模型的正确性和有效性。     

废水深度氧化过程(AOP)中的自由基

对废水的深度氧化,包括光化学氧化,超声波氧化过程中自由基的种类、捕获技术与氧化方式进行了简述。     

事件驱动编程在面向方面软件开发中的应用

基于事件驱动编程原理,提出方面事件处理器(Aspect Event Handler,AEH)方法,用以有效地处理面向方面软件系统中出现的各类横切功能的调用与维护.结合其在 Java EE 银行业务系统 CrossDebit 相关模块开发中的应用,详细介绍 AEH 方法的实际应用流程和技巧.     

AOP及其在状态机工作流中的应用

面向切面编程(Aspect-Oriented Programming,简称AOP)作为一种新的编程技术正日益引起人们的关注.文章介绍了AOP产生背景和理论价值,并结合作者所设计的状态机工作流框架,详细讨论了如何通过在该框架中引入AOP机制来克服纯面向对象编程的不足,从中分析了AOP的优势和应用价值,最后对AOP和OOP的关系进行了讨论.     

AOP event manager in open service gateway〖WT5\"HZ〗Abstract:〖WT5\"BZ〗〖WT5”HZ〗Key words:〖WT5”BZ〗

The Open Service Gateway Initiative (OSGi) has played an important role in ubiquitous environments that support interoperability among embedded devices, such as home appliances and network devices. However, the OSGi does not have a common event mechanism yet, and it is difficult to communicate among services asynchronously. In the present work, a common event manager, AspectOriented Event Manager (AOEM), was designed on an OSGi framework. AOEM supports services to generate and provide notification of events. This paper presents the implementation of AOEM as an OSGi bundle with AspectJ. The experiment on transferring between device service and application service demonstrate that AOEM provides good abstraction of the services and convenience.