Novel self-assembled mesalamine–sucralfate complexes: preparation,characterization, and formulation aspects

Two well-known active agents, mesalamine (MES) and sucralfate (SUC), were investigated for possible utilization as fixed-dose combination product. The anti-inflammatory action of MES in association with bioadhesiveness and mucosal healing properties of SUC were considered promising for the development of a new compound containing both molecules, aimed as an improved treatment of ulcerative colitis. The present study investigates the capacity of the two active agents to interact and generate a new and stable entity via self-assembling. Spray-drying was used to co-process the two active principles from an aqueous mixture where the ratio MES:SUC was in the range 25:75, 50:50, and 75:25. The structural data (X-Ray, FTIR, SEM, DSC, and ¹H NMR) have shown that MES and SUC are interacting leading to complexes with properties differing from those of each separate active agent and from their physical blends. ¹H NMR results indicated that complexation occurred when the aqueous suspensions of drugs were mixed, prior to spray-drying. Drug–drug self-assembling was the driving mechanism in the formation of the new entity. Based on the structural data, a hypothetical structure of the complex was proposed. Co-processing of MES and SUC represents a simple and useful procedure to prepare new self-assembled compounds by valorizing the ionic interactions between the two entities. Preliminary studies with oral solid dosage forms based on MES–SUC complexes tested in vitro have shown a controlled MES release, opening the perspective of a new colon-targeted delivery system and a novel class of compounds with therapeutic application in inflammatory bowel diseases.     

Catalytic cracking of mixtures of model bio-oil compounds and gasoil

Key model bio-oil O-compounds representing some of the major oxygenate groups, such as acetic acid, hydroxyacetone and phenol, were mixed with a standard gasoil and tested under fluid catalytic cracking (FCC) conditions in a laboratory-scale unit using an industrial FCC equilibrium catalyst (E-CAT) and a mixture of E-CAT and ZSM-5 additive. As a general trend, acetic acid, phenol or hydroxyacetone when mixed with a conventional gasoil increased the overall conversion, defined as fraction of the feed converted into gases, gasoline and coke, reduced the coke yield and increased fuel gas, LPG and gasoline. The conversion of the gasoil itself over pure E-CAT was not altered significantly by the presence of these compounds. This result could be interpreted by a preferential adsorption of the feed on the catalytic surface instead of the oxygen containing compounds. On the other hand, the ZSM-5 additive effect was attenuated in the presence of the O-compounds, suggesting a preferential interaction of such compounds with the ZSM-5. Up to 10 wt.% of these O-compounds studied can be processed without major problems in a FCC unit except for phenol.     

Liquefaction of municipal waste plastics in VGO over acidic and non-acidic catalysts

Co-processing of municipal waste plastics (MWP) with vacuum gas oil (VGO) over HZSM-5, DHC-8 (commercial silica-alumina catalyst) and cobalt loaded active carbon catalyst has been comparatively studied. Co-processing experiments were carried out under hydrogen atmosphere at temperatures between 425 and 450 °C. The composition, sulphur and chlorine amount of liquid products were determined. The product distribution and the composition of liquids were changed depending upon the temperature and the catalyst type. As expected temperature led to increase in cracking activity of catalysts. DHC-8 and HZSM-5 showed substantially different activities in co-processing due to the difference in their acidity. HZSM-5 gave highest gas yield at all temperatures and highest liquid yield (38.3) at low temperature. Although Co-AC was a neutral catalyst, it showed the cracking activity as well as HZSM-5 and more than DHC-8. No chlorine compound was observed in liquid products. The sulphur amount in liquid products varied with the catalyst type. Although HZSM-5 showed good cracking activity at low temperatures, it gave the liquid product containing highest sulphur amount. By considering both the quantity and quality of liquid fuel obtained from co-processing, it may be concluded that Co-AC gave the best result in the co-processing of the MWP/VGO blend. To observe the effect of metal type loaded on active carbon on catalyst activity, a series of co-processing experiments was also carried out.     

基于iOS的自组网协同处理模型设计与实现

针对移动智能设备在没有网络基础设施的偏远区域,或是自然灾害破坏了网络基础设施,或是网络信号差的区域,无法进行即时通信和资源文件的共享等问题,本文提出了一种基于iOS的自组网协同处理模型。该模型利用iOS的多点连接框架,实现移动终端在中等距离下即时通信、数据文件共享以及信息协同处理。实验结果表明,该协同处理模型使得自组网内的节点能够充分利用其他节点的资源,协同计算、协同存储、共享数据文件,使得自组网整体性能得到较大增强。     

水混工业自动化及循环经济

本文分析了水泥工业的发展，水泥工业自动化、节能及循环经济。     

Products and coke from the conversion of bio-oil acids,esters, aldehydes and ketones over equilibrium FCC catalysts

Reactivity and product distributions in the conversion of five different compounds representing typical species in bio-oils were studied over an equilibrium FCC catalyst at 500 °C during 60 s in a fixed bed reactor. Acetic acid, methyl acetate, furfural, 3-methyl-2-pentanone and 2-hidroxy-3-methylcyclopentenone were dissolved at 5% wt. in water. Thermal conversions were performed under the same conditions with inert SiC in the bed. The test compounds converted very differently, deoxygenation being produced by decarboxylation and dehydration. Furfural and 3-methyl-2-pentanone gave the highest yields of hydrocarbons, with high selectivity to light olefins and, when liquid (case of ketones), to aromatics. Methyl acetate gave the highest yield of oxygenated compounds. Coke yields were important (maximum 12.8% wt., 2-hidroxy-3-methylcyclopentenone). Thermal conversions were similar to the catalytic ones with acetic acid and methyl acetate, and much lower for the other reactants. Compared catalytic experiments, the thermal yields of hydrocarbons were much higher with acetic acid, and the yields of oxygenated higher with methyl acetate ester. Much less hydrocarbons were produced thermally with the other reactants. This information may be useful for predicting contributions if these compounds are to be co-processed in existing FCC units or upgraded over acidic catalysts.     

基于Xilinx SoPC的可重构嵌入式计算系统的研究与设计

由于应用种类、实时性以及处理效率等要求,高性能嵌入式计算硬件平台需要具备相当的计算能力以及一定的适应性。为此提出了一种基于Xilinx FPGA的动态可重构的片上系统设计方案。系统采用专用硬件来执行计算密集型任务,运用动态可重构技术来支持硬件处理模块功能的动态配置。研究了Xilinx可编程片上系统上的3种硬件加速方案:CPU协处理器、PLB扩展加速器和MPMC扩展加速器。实验数据表明MPMC加速器性能最优。在Vir-tex5 FPGA器件上实现了可动态重构的MPMC加速器,以128位AES加密、解密两个功能模块为例,从硬件资源占用率、重构延时等角度考察了可重构系统的特点。     

Co-processing of sulfidic mining wastes and metal-rich post-consumer wastes by biohydrometallurgy

The consequence of a strong economic growth in emerging countries combined with the rise of the world population is an increase in the demand for raw materials, leading to growing concern regarding their availability and the global efficiency of the supply chain. These tensions reinforce the need to associate the development of the recycling industry to the identification of new resources which could be used for the recovery of valuable materials. The purpose of this study is to develop a novel biological co-processing approach for the recovery of strategic metals in both sulfidic mining wastes and post-consumer wastes (WEEE). The principle of this treatment is based on two steps: mine wastes are biologically oxidized, resulting in the production of a ferric iron-sulfuric acid lixiviant solution which is used to leach base and other soluble metals contained in e-scraps. Batch tests were carried out using flotation tailings wastes containing 60% of pyrite and grinded Printed Circuit Boards (PCB < 750 μm) with a solid load of 2.5%. Two series of tests were conducted in order to study the influence of the ferric iron concentration and of the bacterial activity on metals dissolution. Results showed that a higher ferric iron concentration led to an increase in the dissolution rate of copper which is the main metal contained in the PCBs. Moreover, a dissolution yield of 98.3% was reached for copper after 2 days when bacterial activity was observed, corresponding to an increase of about 20% compared to the tests without bacterial activity. Finally, this study highlights the importance of the availability of ferric iron and of the bacterial oxidation of ferrous iron for the feasibility of this bioleaching process dealing with the recycling of PCBs.     

Modification of α-lactose monohydrate as a direct compression excipient using roller compaction

Abstract

Roller compaction was used to prepare a direct-compressed lactose excipient using crystalline α-lactose monohydrate. The effect of various roller compaction process parameters (compaction pressure, compaction repetition, and speed ratio) on the characteristics of compacted α-lactose monohydrate was investigated. Results were compared with data obtained using industrial spray-dried lactose and lactose samples with different degrees of crystallinity. XRPD analysis revealed that roller compaction reduced the crystallinity of α-lactose monohydrate, and the resulting material is similar to spray-dried lactose in behavior as a direct compression excipient. Roller compaction introduced desirable characteristics to the raw α-lactose monohydrate by inducing changes in crystallinity and particle morphology. Scanning electron microscopy results indicated that the compaction process converted some of the original torpedo-shaped crystals of α-lactose monohydrate into a more cylindrical shape with rounded edges. Compaction pressure and repetition of compaction have a significant effect on the modification of the crystallinity of the processed, raw α-lactose monohydrate.     

Acid leaching of coal and coal-ashes

Twelve Turkish lignites and the corresponding ashes were leached in sulfuric acid (pH 1.0, 25 °C) for 14 days. Asphaltite from Silopi amended the coals. The conditions mimic treatment in the effluent from bioleaching of sulfidic mineral concentrates, but the results are equally valid for an isolated leaching process. The extended time meant that we approached equilibrium and maximum extraction.The coals have limited neutralizing capacity. H₂SO₄ (1.0-2.0 l, 1 M) was needed to stabilize 1 kg coal at pH 1.0 (liquid:solid ratio 10:1), but the coal-ashes required 18.0-24.0 l/kg dry solid, which is the neutralizing equivalent to CaO.Leaching of dominant inorganic phases consume acid, but our interest is merely to remove trace elements present as dopants. We removed large fractions of Mg and Mn, but Al, K and Na extractions were limited by the presence of stable minerals and bimetallic oxides. The formation of the latter is driven by combustion at high temperatures. Alumina, normally not stable at pH 1.0, was protected from the effluent by the organic phase in coal. Fe leaching varied and appeared to be a marker for different chemical occurrences in the solids.Cd, V, Zn, U and Th were leached to near 80% from the ashes, but considerably less from the coals. Co and Ni extractions were near 60%, but not always higher from the ashes compared with the coals. Cu yields increase following ashing and reached ca. 60%. Ti, Ba, and Cs were not leached.We suggest that direct acid leaching is of interest to limit the deleterious impact of ash deposits and to recirculate metals from the ash. Ash may partly replace limestone in hydrometallurgical processing, but, more importantly, metal ions extracted from ash may be fed into the metal recovery stages of such processes. It is particularly interesting to leach Co, Cu, Ni and Zn, besides Mn, V and the environmentally hazardous Cd, U and Th. Leaching of whole coals is well motivated for domestic use-lump sizes around 18-50 mm, or slightly smaller, 10 mm, if mandated by practical residence times—where generally no other measures are taken to protect the local environment.